diff options
Diffstat (limited to 'Documentation')
67 files changed, 3094 insertions, 307 deletions
diff --git a/Documentation/ABI/testing/sysfs-fs-ext4 b/Documentation/ABI/testing/sysfs-fs-ext4 index 4e79074de282..5fb709997d96 100644 --- a/Documentation/ABI/testing/sysfs-fs-ext4 +++ b/Documentation/ABI/testing/sysfs-fs-ext4 @@ -79,3 +79,13 @@ Description: This file is read-only and shows the number of kilobytes of data that have been written to this filesystem since it was mounted. + +What: /sys/fs/ext4/<disk>/inode_goal +Date: June 2008 +Contact: "Theodore Ts'o" <tytso@mit.edu> +Description: + Tuning parameter which (if non-zero) controls the goal + inode used by the inode allocator in p0reference to + all other allocation hueristics. This is intended for + debugging use only, and should be 0 on production + systems. diff --git a/Documentation/ABI/testing/sysfs-pps b/Documentation/ABI/testing/sysfs-pps new file mode 100644 index 000000000000..25028c7bc37d --- /dev/null +++ b/Documentation/ABI/testing/sysfs-pps @@ -0,0 +1,73 @@ +What: /sys/class/pps/ +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ directory will contain files and + directories that will provide a unified interface to + the PPS sources. + +What: /sys/class/pps/ppsX/ +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/ directory is related to X-th + PPS source into the system. Each directory will + contain files to manage and control its PPS source. + +What: /sys/class/pps/ppsX/assert +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/assert file reports the assert events + and the assert sequence number of the X-th source in the form: + + <secs>.<nsec>#<sequence> + + If the source has no assert events the content of this file + is empty. + +What: /sys/class/pps/ppsX/clear +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/clear file reports the clear events + and the clear sequence number of the X-th source in the form: + + <secs>.<nsec>#<sequence> + + If the source has no clear events the content of this file + is empty. + +What: /sys/class/pps/ppsX/mode +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/mode file reports the functioning + mode of the X-th source in hexadecimal encoding. + + Please, refer to linux/include/linux/pps.h for further + info. + +What: /sys/class/pps/ppsX/echo +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/echo file reports if the X-th does + or does not support an "echo" function. + +What: /sys/class/pps/ppsX/name +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/name file reports the name of the + X-th source. + +What: /sys/class/pps/ppsX/path +Date: February 2008 +Contact: Rodolfo Giometti <giometti@linux.it> +Description: + The /sys/class/pps/ppsX/path file reports the path name of + the device connected with the X-th source. + + If the source is not connected with any device the content + of this file is empty. diff --git a/Documentation/Changes b/Documentation/Changes index 664392481c84..6d0f1efc5bf6 100644 --- a/Documentation/Changes +++ b/Documentation/Changes @@ -72,6 +72,13 @@ assembling the 16-bit boot code, removing the need for as86 to compile your kernel. This change does, however, mean that you need a recent release of binutils. +Perl +---- + +You will need perl 5 and the following modules: Getopt::Long, Getopt::Std, +File::Basename, and File::Find to build the kernel. + + System utilities ================ diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl index 7f5f218015fe..08ff908aa7a2 100644 --- a/Documentation/DocBook/debugobjects.tmpl +++ b/Documentation/DocBook/debugobjects.tmpl @@ -106,7 +106,7 @@ number of errors are printk'ed including a full stack trace. </para> <para> - The statistics are available via debugfs/debug_objects/stats. + The statistics are available via /sys/kernel/debug/debug_objects/stats. They provide information about the number of warnings and the number of successful fixups along with information about the usage of the internal tracking objects and the state of the diff --git a/Documentation/SubmitChecklist b/Documentation/SubmitChecklist index ac5e0b2f1097..78a9168ff377 100644 --- a/Documentation/SubmitChecklist +++ b/Documentation/SubmitChecklist @@ -54,7 +54,7 @@ kernel patches. CONFIG_PREEMPT. 14: If the patch affects IO/Disk, etc: has been tested with and without - CONFIG_LBD. + CONFIG_LBDAF. 15: All codepaths have been exercised with all lockdep features enabled. diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c index 7ea231172c85..aa73e72fd793 100644 --- a/Documentation/accounting/getdelays.c +++ b/Documentation/accounting/getdelays.c @@ -246,7 +246,8 @@ void print_ioacct(struct taskstats *t) int main(int argc, char *argv[]) { - int c, rc, rep_len, aggr_len, len2, cmd_type; + int c, rc, rep_len, aggr_len, len2; + int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC; __u16 id; __u32 mypid; diff --git a/Documentation/atomic_ops.txt b/Documentation/atomic_ops.txt index 4ef245010457..396bec3b74ed 100644 --- a/Documentation/atomic_ops.txt +++ b/Documentation/atomic_ops.txt @@ -229,10 +229,10 @@ kernel. It is the use of atomic counters to implement reference counting, and it works such that once the counter falls to zero it can be guaranteed that no other entity can be accessing the object: -static void obj_list_add(struct obj *obj) +static void obj_list_add(struct obj *obj, struct list_head *head) { obj->active = 1; - list_add(&obj->list); + list_add(&obj->list, head); } static void obj_list_del(struct obj *obj) diff --git a/Documentation/cdrom/packet-writing.txt b/Documentation/cdrom/packet-writing.txt index cf1f8126991c..1c407778c8b2 100644 --- a/Documentation/cdrom/packet-writing.txt +++ b/Documentation/cdrom/packet-writing.txt @@ -117,7 +117,7 @@ Using the pktcdvd debugfs interface To read pktcdvd device infos in human readable form, do: - # cat /debug/pktcdvd/pktcdvd[0-7]/info + # cat /sys/kernel/debug/pktcdvd/pktcdvd[0-7]/info For a description of the debugfs interface look into the file: diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt index 1a608877b14e..23d1262c0775 100644 --- a/Documentation/cgroups/memory.txt +++ b/Documentation/cgroups/memory.txt @@ -152,14 +152,19 @@ When swap is accounted, following files are added. usage of mem+swap is limited by memsw.limit_in_bytes. -Note: why 'mem+swap' rather than swap. +* why 'mem+swap' rather than swap. The global LRU(kswapd) can swap out arbitrary pages. Swap-out means to move account from memory to swap...there is no change in usage of -mem+swap. +mem+swap. In other words, when we want to limit the usage of swap without +affecting global LRU, mem+swap limit is better than just limiting swap from +OS point of view. -In other words, when we want to limit the usage of swap without affecting -global LRU, mem+swap limit is better than just limiting swap from OS point -of view. +* What happens when a cgroup hits memory.memsw.limit_in_bytes +When a cgroup his memory.memsw.limit_in_bytes, it's useless to do swap-out +in this cgroup. Then, swap-out will not be done by cgroup routine and file +caches are dropped. But as mentioned above, global LRU can do swapout memory +from it for sanity of the system's memory management state. You can't forbid +it by cgroup. 2.5 Reclaim @@ -204,6 +209,7 @@ We can alter the memory limit: NOTE: We can use a suffix (k, K, m, M, g or G) to indicate values in kilo, mega or gigabytes. +NOTE: We can write "-1" to reset the *.limit_in_bytes(unlimited). # cat /cgroups/0/memory.limit_in_bytes 4194304 diff --git a/Documentation/connector/cn_test.c b/Documentation/connector/cn_test.c index 6977c178729a..f688eba87704 100644 --- a/Documentation/connector/cn_test.c +++ b/Documentation/connector/cn_test.c @@ -41,6 +41,12 @@ void cn_test_callback(void *data) msg->seq, msg->ack, msg->len, (char *)msg->data); } +/* + * Do not remove this function even if no one is using it as + * this is an example of how to get notifications about new + * connector user registration + */ +#if 0 static int cn_test_want_notify(void) { struct cn_ctl_msg *ctl; @@ -117,6 +123,7 @@ nlmsg_failure: kfree_skb(skb); return -EINVAL; } +#endif static u32 cn_test_timer_counter; static void cn_test_timer_func(unsigned long __data) diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt index 43c743903dd7..75a58d14d3cf 100644 --- a/Documentation/cpu-freq/cpu-drivers.txt +++ b/Documentation/cpu-freq/cpu-drivers.txt @@ -155,7 +155,7 @@ actual frequency must be determined using the following rules: - if relation==CPUFREQ_REL_H, try to select a new_freq lower than or equal target_freq. ("H for highest, but no higher than") -Here again the frequency table helper might assist you - see section 3 +Here again the frequency table helper might assist you - see section 2 for details. diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index ce73f3eb5ddb..aed082f49d09 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -119,10 +119,6 @@ want the kernel to look at the CPU usage and to make decisions on what to do about the frequency. Typically this is set to values of around '10000' or more. It's default value is (cmp. with users-guide.txt): transition_latency * 1000 -The lowest value you can set is: -transition_latency * 100 or it may get restricted to a value where it -makes not sense for the kernel anymore to poll that often which depends -on your HZ config variable (HZ=1000: max=20000us, HZ=250: max=5000). Be aware that transition latency is in ns and sampling_rate is in us, so you get the same sysfs value by default. Sampling rate should always get adjusted considering the transition latency @@ -131,14 +127,20 @@ in the bash (as said, 1000 is default), do: echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) \ >ondemand/sampling_rate -show_sampling_rate_(min|max): THIS INTERFACE IS DEPRECATED, DON'T USE IT. -You can use wider ranges now and the general -cpuinfo_transition_latency variable (cmp. with user-guide.txt) can be -used to obtain exactly the same info: -show_sampling_rate_min = transtition_latency * 500 / 1000 -show_sampling_rate_max = transtition_latency * 500000 / 1000 -(divided by 1000 is to illustrate that sampling rate is in us and -transition latency is exported ns). +show_sampling_rate_min: +The sampling rate is limited by the HW transition latency: +transition_latency * 100 +Or by kernel restrictions: +If CONFIG_NO_HZ is set, the limit is 10ms fixed. +If CONFIG_NO_HZ is not set or no_hz=off boot parameter is used, the +limits depend on the CONFIG_HZ option: +HZ=1000: min=20000us (20ms) +HZ=250: min=80000us (80ms) +HZ=100: min=200000us (200ms) +The highest value of kernel and HW latency restrictions is shown and +used as the minimum sampling rate. + +show_sampling_rate_max: THIS INTERFACE IS DEPRECATED, DON'T USE IT. up_threshold: defines what the average CPU usage between the samplings of 'sampling_rate' needs to be for the kernel to make a decision on diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt index 75f41193f3e1..5d5f5fadd1c2 100644 --- a/Documentation/cpu-freq/user-guide.txt +++ b/Documentation/cpu-freq/user-guide.txt @@ -31,7 +31,6 @@ Contents: 3. How to change the CPU cpufreq policy and/or speed 3.1 Preferred interface: sysfs -3.2 Deprecated interfaces diff --git a/Documentation/driver-model/device.txt b/Documentation/driver-model/device.txt index a7cbfff40d07..a124f3126b0d 100644 --- a/Documentation/driver-model/device.txt +++ b/Documentation/driver-model/device.txt @@ -162,3 +162,35 @@ device_remove_file(dev,&dev_attr_power); The file name will be 'power' with a mode of 0644 (-rw-r--r--). +Word of warning: While the kernel allows device_create_file() and +device_remove_file() to be called on a device at any time, userspace has +strict expectations on when attributes get created. When a new device is +registered in the kernel, a uevent is generated to notify userspace (like +udev) that a new device is available. If attributes are added after the +device is registered, then userspace won't get notified and userspace will +not know about the new attributes. + +This is important for device driver that need to publish additional +attributes for a device at driver probe time. If the device driver simply +calls device_create_file() on the device structure passed to it, then +userspace will never be notified of the new attributes. Instead, it should +probably use class_create() and class->dev_attrs to set up a list of +desired attributes in the modules_init function, and then in the .probe() +hook, and then use device_create() to create a new device as a child +of the probed device. The new device will generate a new uevent and +properly advertise the new attributes to userspace. + +For example, if a driver wanted to add the following attributes: +struct device_attribute mydriver_attribs[] = { + __ATTR(port_count, 0444, port_count_show), + __ATTR(serial_number, 0444, serial_number_show), + NULL +}; + +Then in the module init function is would do: + mydriver_class = class_create(THIS_MODULE, "my_attrs"); + mydriver_class.dev_attr = mydriver_attribs; + +And assuming 'dev' is the struct device passed into the probe hook, the driver +probe function would do something like: + create_device(&mydriver_class, dev, chrdev, &private_data, "my_name"); diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index 2f21ecd4c205..a52adfc9a57f 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -112,7 +112,7 @@ sub tda10045 { sub tda10046 { my $sourcefile = "TT_PCI_2.19h_28_11_2006.zip"; - my $url = "http://technotrend-online.com/download/software/219/$sourcefile"; + my $url = "http://www.tt-download.com/download/updates/219/$sourcefile"; my $hash = "6a7e1e2f2644b162ff0502367553c72d"; my $outfile = "dvb-fe-tda10046.fw"; my $tmpdir = tempdir(DIR => "/tmp", CLEANUP => 1); @@ -129,8 +129,8 @@ sub tda10046 { } sub tda10046lifeview { - my $sourcefile = "Drv_2.11.02.zip"; - my $url = "http://www.lifeview.com.tw/drivers/pci_card/FlyDVB-T/$sourcefile"; + my $sourcefile = "7%5Cdrv_2.11.02.zip"; + my $url = "http://www.lifeview.hk/dbimages/document/$sourcefile"; my $hash = "1ea24dee4eea8fe971686981f34fd2e0"; my $outfile = "dvb-fe-tda10046.fw"; my $tmpdir = tempdir(DIR => "/tmp", CLEANUP => 1); @@ -317,7 +317,7 @@ sub nxt2002 { sub nxt2004 { my $sourcefile = "AVerTVHD_MCE_A180_Drv_v1.2.2.16.zip"; - my $url = "http://www.aver.com/support/Drivers/$sourcefile"; + my $url = "http://www.avermedia-usa.com/support/Drivers/$sourcefile"; my $hash = "111cb885b1e009188346d72acfed024c"; my $outfile = "dvb-fe-nxt2004.fw"; my $tmpdir = tempdir(DIR => "/tmp", CLEANUP => 1); diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt index 4bc374a14345..079305640790 100644 --- a/Documentation/fault-injection/fault-injection.txt +++ b/Documentation/fault-injection/fault-injection.txt @@ -29,16 +29,16 @@ o debugfs entries fault-inject-debugfs kernel module provides some debugfs entries for runtime configuration of fault-injection capabilities. -- /debug/fail*/probability: +- /sys/kernel/debug/fail*/probability: likelihood of failure injection, in percent. Format: <percent> Note that one-failure-per-hundred is a very high error rate for some testcases. Consider setting probability=100 and configure - /debug/fail*/interval for such testcases. + /sys/kernel/debug/fail*/interval for such testcases. -- /debug/fail*/interval: +- /sys/kernel/debug/fail*/interval: specifies the interval between failures, for calls to should_fail() that pass all the other tests. @@ -46,18 +46,18 @@ configuration of fault-injection capabilities. Note that if you enable this, by setting interval>1, you will probably want to set probability=100. -- /debug/fail*/times: +- /sys/kernel/debug/fail*/times: specifies how many times failures may happen at most. A value of -1 means "no limit". -- /debug/fail*/space: +- /sys/kernel/debug/fail*/space: specifies an initial resource "budget", decremented by "size" on each call to should_fail(,size). Failure injection is suppressed until "space" reaches zero. -- /debug/fail*/verbose +- /sys/kernel/debug/fail*/verbose Format: { 0 | 1 | 2 } specifies the verbosity of the messages when failure is @@ -65,17 +65,17 @@ configuration of fault-injection capabilities. log line per failure; '2' will print a call trace too -- useful to debug the problems revealed by fault injection. -- /debug/fail*/task-filter: +- /sys/kernel/debug/fail*/task-filter: Format: { 'Y' | 'N' } A value of 'N' disables filtering by process (default). Any positive value limits failures to only processes indicated by /proc/<pid>/make-it-fail==1. -- /debug/fail*/require-start: -- /debug/fail*/require-end: -- /debug/fail*/reject-start: -- /debug/fail*/reject-end: +- /sys/kernel/debug/fail*/require-start: +- /sys/kernel/debug/fail*/require-end: +- /sys/kernel/debug/fail*/reject-start: +- /sys/kernel/debug/fail*/reject-end: specifies the range of virtual addresses tested during stacktrace walking. Failure is injected only if some caller @@ -84,26 +84,26 @@ configuration of fault-injection capabilities. Default required range is [0,ULONG_MAX) (whole of virtual address space). Default rejected range is [0,0). -- /debug/fail*/stacktrace-depth: +- /sys/kernel/debug/fail*/stacktrace-depth: specifies the maximum stacktrace depth walked during search for a caller within [require-start,require-end) OR [reject-start,reject-end). -- /debug/fail_page_alloc/ignore-gfp-highmem: +- /sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem: Format: { 'Y' | 'N' } default is 'N', setting it to 'Y' won't inject failures into highmem/user allocations. -- /debug/failslab/ignore-gfp-wait: -- /debug/fail_page_alloc/ignore-gfp-wait: +- /sys/kernel/debug/failslab/ignore-gfp-wait: +- /sys/kernel/debug/fail_page_alloc/ignore-gfp-wait: Format: { 'Y' | 'N' } default is 'N', setting it to 'Y' will inject failures only into non-sleep allocations (GFP_ATOMIC allocations). -- /debug/fail_page_alloc/min-order: +- /sys/kernel/debug/fail_page_alloc/min-order: specifies the minimum page allocation order to be injected failures. @@ -166,13 +166,13 @@ o Inject slab allocation failures into module init/exit code #!/bin/bash FAILTYPE=failslab -echo Y > /debug/$FAILTYPE/task-filter -echo 10 > /debug/$FAILTYPE/probability -echo 100 > /debug/$FAILTYPE/interval -echo -1 > /debug/$FAILTYPE/times -echo 0 > /debug/$FAILTYPE/space -echo 2 > /debug/$FAILTYPE/verbose -echo 1 > /debug/$FAILTYPE/ignore-gfp-wait +echo Y > /sys/kernel/debug/$FAILTYPE/task-filter +echo 10 > /sys/kernel/debug/$FAILTYPE/probability +echo 100 > /sys/kernel/debug/$FAILTYPE/interval +echo -1 > /sys/kernel/debug/$FAILTYPE/times +echo 0 > /sys/kernel/debug/$FAILTYPE/space +echo 2 > /sys/kernel/debug/$FAILTYPE/verbose +echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait faulty_system() { @@ -217,20 +217,20 @@ then exit 1 fi -cat /sys/module/$module/sections/.text > /debug/$FAILTYPE/require-start -cat /sys/module/$module/sections/.data > /debug/$FAILTYPE/require-end +cat /sys/module/$module/sections/.text > /sys/kernel/debug/$FAILTYPE/require-start +cat /sys/module/$module/sections/.data > /sys/kernel/debug/$FAILTYPE/require-end -echo N > /debug/$FAILTYPE/task-filter -echo 10 > /debug/$FAILTYPE/probability -echo 100 > /debug/$FAILTYPE/interval -echo -1 > /debug/$FAILTYPE/times -echo 0 > /debug/$FAILTYPE/space -echo 2 > /debug/$FAILTYPE/verbose -echo 1 > /debug/$FAILTYPE/ignore-gfp-wait -echo 1 > /debug/$FAILTYPE/ignore-gfp-highmem -echo 10 > /debug/$FAILTYPE/stacktrace-depth +echo N > /sys/kernel/debug/$FAILTYPE/task-filter +echo 10 > /sys/kernel/debug/$FAILTYPE/probability +echo 100 > /sys/kernel/debug/$FAILTYPE/interval +echo -1 > /sys/kernel/debug/$FAILTYPE/times +echo 0 > /sys/kernel/debug/$FAILTYPE/space +echo 2 > /sys/kernel/debug/$FAILTYPE/verbose +echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-wait +echo 1 > /sys/kernel/debug/$FAILTYPE/ignore-gfp-highmem +echo 10 > /sys/kernel/debug/$FAILTYPE/stacktrace-depth -trap "echo 0 > /debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT +trap "echo 0 > /sys/kernel/debug/$FAILTYPE/probability" SIGINT SIGTERM EXIT echo "Injecting errors into the module $module... (interrupt to stop)" sleep 1000000 diff --git a/Documentation/fb/vesafb.txt b/Documentation/fb/vesafb.txt index ee277dd204b0..950d5a658cb3 100644 --- a/Documentation/fb/vesafb.txt +++ b/Documentation/fb/vesafb.txt @@ -95,7 +95,7 @@ There is no way to change the vesafb video mode and/or timings after booting linux. If you are not happy with the 60 Hz refresh rate, you have these options: - * configure and load the DOS-Tools for your the graphics board (if + * configure and load the DOS-Tools for the graphics board (if available) and boot linux with loadlin. * use a native driver (matroxfb/atyfb) instead if vesafb. If none is available, write a new one! diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 7129846a2785..f8cd450be9aa 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -6,6 +6,20 @@ be removed from this file. --------------------------- +What: IRQF_SAMPLE_RANDOM +Check: IRQF_SAMPLE_RANDOM +When: July 2009 + +Why: Many of IRQF_SAMPLE_RANDOM users are technically bogus as entropy + sources in the kernel's current entropy model. To resolve this, every + input point to the kernel's entropy pool needs to better document the + type of entropy source it actually is. This will be replaced with + additional add_*_randomness functions in drivers/char/random.c + +Who: Robin Getz <rgetz@blackfin.uclinux.org> & Matt Mackall <mpm@selenic.com> + +--------------------------- + What: The ieee80211_regdom module parameter When: March 2010 / desktop catchup @@ -354,16 +368,6 @@ Who: Krzysztof Piotr Oledzki <ole@ans.pl> --------------------------- -What: i2c_attach_client(), i2c_detach_client(), i2c_driver->detach_client(), - i2c_adapter->client_register(), i2c_adapter->client_unregister -When: 2.6.30 -Check: i2c_attach_client i2c_detach_client -Why: Deprecated by the new (standard) device driver binding model. Use - i2c_driver->probe() and ->remove() instead. -Who: Jean Delvare <khali@linux-fr.org> - ---------------------------- - What: fscher and fscpos drivers When: June 2009 Why: Deprecated by the new fschmd driver. diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 3120f8dd2c31..229d7b7c50a3 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -187,7 +187,7 @@ readpages: no write_begin: no locks the page yes write_end: no yes, unlocks yes perform_write: no n/a yes -bmap: yes +bmap: no invalidatepage: no yes releasepage: no yes direct_IO: no diff --git a/Documentation/filesystems/ext2.txt b/Documentation/filesystems/ext2.txt index e055acb6b2d4..67639f905f10 100644 --- a/Documentation/filesystems/ext2.txt +++ b/Documentation/filesystems/ext2.txt @@ -322,7 +322,7 @@ an upper limit on the block size imposed by the page size of the kernel, so 8kB blocks are only allowed on Alpha systems (and other architectures which support larger pages). -There is an upper limit of 32768 subdirectories in a single directory. +There is an upper limit of 32000 subdirectories in a single directory. There is a "soft" upper limit of about 10-15k files in a single directory with the current linear linked-list directory implementation. This limit diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 608fdba97b72..7be02ac5fa36 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -235,6 +235,10 @@ minixdf Make 'df' act like Minix. debug Extra debugging information is sent to syslog. +abort Simulate the effects of calling ext4_abort() for + debugging purposes. This is normally used while + remounting a filesystem which is already mounted. + errors=remount-ro Remount the filesystem read-only on an error. errors=continue Keep going on a filesystem error. errors=panic Panic and halt the machine if an error occurs. diff --git a/Documentation/filesystems/isofs.txt b/Documentation/filesystems/isofs.txt index 6973b980ca2a..3c367c3b3608 100644 --- a/Documentation/filesystems/isofs.txt +++ b/Documentation/filesystems/isofs.txt @@ -23,8 +23,13 @@ Mount options unique to the isofs filesystem. map=off Do not map non-Rock Ridge filenames to lower case map=normal Map non-Rock Ridge filenames to lower case map=acorn As map=normal but also apply Acorn extensions if present - mode=xxx Sets the permissions on files to xxx - dmode=xxx Sets the permissions on directories to xxx + mode=xxx Sets the permissions on files to xxx unless Rock Ridge + extensions set the permissions otherwise + dmode=xxx Sets the permissions on directories to xxx unless Rock Ridge + extensions set the permissions otherwise + overriderockperm Set permissions on files and directories according to + 'mode' and 'dmode' even though Rock Ridge extensions are + present. nojoliet Ignore Joliet extensions if they are present. norock Ignore Rock Ridge extensions if they are present. hide Completely strip hidden files from the file system. diff --git a/Documentation/filesystems/nilfs2.txt b/Documentation/filesystems/nilfs2.txt index 55c4300abfcb..01539f410676 100644 --- a/Documentation/filesystems/nilfs2.txt +++ b/Documentation/filesystems/nilfs2.txt @@ -39,9 +39,8 @@ Features which NILFS2 does not support yet: - extended attributes - POSIX ACLs - quotas - - writable snapshots - - remote backup (CDP) - - data integrity + - fsck + - resize - defragmentation Mount options diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index cd8717a36271..fad18f9456e4 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -5,11 +5,12 @@ Bodo Bauer <bb@ricochet.net> 2.4.x update Jorge Nerin <comandante@zaralinux.com> November 14 2000 -move /proc/sys Shen Feng <shen@cn.fujitsu.com> April 1 2009 +move /proc/sys Shen Feng <shen@cn.fujitsu.com> April 1 2009 ------------------------------------------------------------------------------ Version 1.3 Kernel version 2.2.12 Kernel version 2.4.0-test11-pre4 ------------------------------------------------------------------------------ +fixes/update part 1.1 Stefani Seibold <stefani@seibold.net> June 9 2009 Table of Contents ----------------- @@ -116,7 +117,7 @@ The link self points to the process reading the file system. Each process subdirectory has the entries listed in Table 1-1. -Table 1-1: Process specific entries in /proc +Table 1-1: Process specific entries in /proc .............................................................................. File Content clear_refs Clears page referenced bits shown in smaps output @@ -134,46 +135,103 @@ Table 1-1: Process specific entries in /proc status Process status in human readable form wchan If CONFIG_KALLSYMS is set, a pre-decoded wchan stack Report full stack trace, enable via CONFIG_STACKTRACE - smaps Extension based on maps, the rss size for each mapped file + smaps a extension based on maps, showing the memory consumption of + each mapping .............................................................................. For example, to get the status information of a process, all you have to do is read the file /proc/PID/status: - >cat /proc/self/status - Name: cat - State: R (running) - Pid: 5452 - PPid: 743 + >cat /proc/self/status + Name: cat + State: R (running) + Tgid: 5452 + Pid: 5452 + PPid: 743 TracerPid: 0 (2.4) - Uid: 501 501 501 501 - Gid: 100 100 100 100 - Groups: 100 14 16 - VmSize: 1112 kB - VmLck: 0 kB - VmRSS: 348 kB - VmData: 24 kB - VmStk: 12 kB - VmExe: 8 kB - VmLib: 1044 kB - SigPnd: 0000000000000000 - SigBlk: 0000000000000000 - SigIgn: 0000000000000000 - SigCgt: 0000000000000000 - CapInh: 00000000fffffeff - CapPrm: 0000000000000000 - CapEff: 0000000000000000 - + Uid: 501 501 501 501 + Gid: 100 100 100 100 + FDSize: 256 + Groups: 100 14 16 + VmPeak: 5004 kB + VmSize: 5004 kB + VmLck: 0 kB + VmHWM: 476 kB + VmRSS: 476 kB + VmData: 156 kB + VmStk: 88 kB + VmExe: 68 kB + VmLib: 1412 kB + VmPTE: 20 kb + Threads: 1 + SigQ: 0/28578 + SigPnd: 0000000000000000 + ShdPnd: 0000000000000000 + SigBlk: 0000000000000000 + SigIgn: 0000000000000000 + SigCgt: 0000000000000000 + CapInh: 00000000fffffeff + CapPrm: 0000000000000000 + CapEff: 0000000000000000 + CapBnd: ffffffffffffffff + voluntary_ctxt_switches: 0 + nonvoluntary_ctxt_switches: 1 This shows you nearly the same information you would get if you viewed it with the ps command. In fact, ps uses the proc file system to obtain its -information. The statm file contains more detailed information about the -process memory usage. Its seven fields are explained in Table 1-2. The stat -file contains details information about the process itself. Its fields are -explained in Table 1-3. +information. But you get a more detailed view of the process by reading the +file /proc/PID/status. It fields are described in table 1-2. + +The statm file contains more detailed information about the process +memory usage. Its seven fields are explained in Table 1-3. The stat file +contains details information about the process itself. Its fields are +explained in Table 1-4. +Table 1-2: Contents of the statm files (as of 2.6.30-rc7) +.............................................................................. + Field Content + Name filename of the executable + State state (R is running, S is sleeping, D is sleeping + in an uninterruptible wait, Z is zombie, + T is traced or stopped) + Tgid thread group ID + Pid process id + PPid process id of the parent process + TracerPid PID of process tracing this process (0 if not) + Uid Real, effective, saved set, and file system UIDs + Gid Real, effective, saved set, and file system GIDs + FDSize number of file descriptor slots currently allocated + Groups supplementary group list + VmPeak peak virtual memory size + VmSize total program size + VmLck locked memory size + VmHWM peak resident set size ("high water mark") + VmRSS size of memory portions + VmData size of data, stack, and text segments + VmStk size of data, stack, and text segments + VmExe size of text segment + VmLib size of shared library code + VmPTE size of page table entries + Threads number of threads + SigQ number of signals queued/max. number for queue + SigPnd bitmap of pending signals for the thread + ShdPnd bitmap of shared pending signals for the process + SigBlk bitmap of blocked signals + SigIgn bitmap of ignored signals + SigCgt bitmap of catched signals + CapInh bitmap of inheritable capabilities + CapPrm bitmap of permitted capabilities + CapEff bitmap of effective capabilities + CapBnd bitmap of capabilities bounding set + Cpus_allowed mask of CPUs on which this process may run + Cpus_allowed_list Same as previous, but in "list format" + Mems_allowed mask of memory nodes allowed to this process + Mems_allowed_list Same as previous, but in "list format" + voluntary_ctxt_switches number of voluntary context switches + nonvoluntary_ctxt_switches number of non voluntary context switches +.............................................................................. -Table 1-2: Contents of the statm files (as of 2.6.8-rc3) +Table 1-3: Contents of the statm files (as of 2.6.8-rc3) .............................................................................. Field Content size total program size (pages) (same as VmSize in status) @@ -188,7 +246,7 @@ Table 1-2: Contents of the statm files (as of 2.6.8-rc3) .............................................................................. -Table 1-3: Contents of the stat files (as of 2.6.22-rc3) +Table 1-4: Contents of the stat files (as of 2.6.30-rc7) .............................................................................. Field Content pid process id @@ -222,10 +280,10 @@ Table 1-3: Contents of the stat files (as of 2.6.22-rc3) start_stack address of the start of the stack esp current value of ESP eip current value of EIP - pending bitmap of pending signals (obsolete) - blocked bitmap of blocked signals (obsolete) - sigign bitmap of ignored signals (obsolete) - sigcatch bitmap of catched signals (obsolete) + pending bitmap of pending signals + blocked bitmap of blocked signals + sigign bitmap of ignored signals + sigcatch bitmap of catched signals wchan address where process went to sleep 0 (place holder) 0 (place holder) @@ -234,19 +292,99 @@ Table 1-3: Contents of the stat files (as of 2.6.22-rc3) rt_priority realtime priority policy scheduling policy (man sched_setscheduler) blkio_ticks time spent waiting for block IO + gtime guest time of the task in jiffies + cgtime guest time of the task children in jiffies .............................................................................. +The /proc/PID/map file containing the currently mapped memory regions and +their access permissions. + +The format is: + +address perms offset dev inode pathname + +08048000-08049000 r-xp 00000000 03:00 8312 /opt/test +08049000-0804a000 rw-p 00001000 03:00 8312 /opt/test +0804a000-0806b000 rw-p 00000000 00:00 0 [heap] +a7cb1000-a7cb2000 ---p 00000000 00:00 0 +a7cb2000-a7eb2000 rw-p 00000000 00:00 0 +a7eb2000-a7eb3000 ---p 00000000 00:00 0 +a7eb3000-a7ed5000 rw-p 00000000 00:00 0 +a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6 +a8008000-a800a000 r--p 00133000 03:00 4222 /lib/libc.so.6 +a800a000-a800b000 rw-p 00135000 03:00 4222 /lib/libc.so.6 +a800b000-a800e000 rw-p 00000000 00:00 0 +a800e000-a8022000 r-xp 00000000 03:00 14462 /lib/libpthread.so.0 +a8022000-a8023000 r--p 00013000 03:00 14462 /lib/libpthread.so.0 +a8023000-a8024000 rw-p 00014000 03:00 14462 /lib/libpthread.so.0 +a8024000-a8027000 rw-p 00000000 00:00 0 +a8027000-a8043000 r-xp 00000000 03:00 8317 /lib/ld-linux.so.2 +a8043000-a8044000 r--p 0001b000 03:00 8317 /lib/ld-linux.so.2 +a8044000-a8045000 rw-p 0001c000 03:00 8317 /lib/ld-linux.so.2 +aff35000-aff4a000 rw-p 00000000 00:00 0 [stack] +ffffe000-fffff000 r-xp 00000000 00:00 0 [vdso] + +where "address" is the address space in the process that it occupies, "perms" +is a set of permissions: + + r = read + w = write + x = execute + s = shared + p = private (copy on write) + +"offset" is the offset into the mapping, "dev" is the device (major:minor), and +"inode" is the inode on that device. 0 indicates that no inode is associated +with the memory region, as the case would be with BSS (uninitialized data). +The "pathname" shows the name associated file for this mapping. If the mapping +is not associated with a file: + + [heap] = the heap of the program + [stack] = the stack of the main process + [vdso] = the "virtual dynamic shared object", + the kernel system call handler + + or if empty, the mapping is anonymous. + + +The /proc/PID/smaps is an extension based on maps, showing the memory +consumption for each of the process's mappings. For each of mappings there +is a series of lines such as the following: + +08048000-080bc000 r-xp 00000000 03:02 13130 /bin/bash +Size: 1084 kB +Rss: 892 kB +Pss: 374 kB +Shared_Clean: 892 kB +Shared_Dirty: 0 kB +Private_Clean: 0 kB +Private_Dirty: 0 kB +Referenced: 892 kB +Swap: 0 kB +KernelPageSize: 4 kB +MMUPageSize: 4 kB + +The first of these lines shows the same information as is displayed for the +mapping in /proc/PID/maps. The remaining lines show the size of the mapping, +the amount of the mapping that is currently resident in RAM, the "proportional +set size” (divide each shared page by the number of processes sharing it), the +number of clean and dirty shared pages in the mapping, and the number of clean +and dirty private pages in the mapping. The "Referenced" indicates the amount +of memory currently marked as referenced or accessed. + +This file is only present if the CONFIG_MMU kernel configuration option is +enabled. 1.2 Kernel data --------------- Similar to the process entries, the kernel data files give information about the running kernel. The files used to obtain this information are contained in -/proc and are listed in Table 1-4. Not all of these will be present in your +/proc and are listed in Table 1-5. Not all of these will be present in your system. It depends on the kernel configuration and the loaded modules, which files are there, and which are missing. -Table 1-4: Kernel info in /proc +Table 1-5: Kernel info in /proc .............................................................................. File Content apm Advanced power management info @@ -283,6 +421,7 @@ Table 1-4: Kernel info in /proc rtc Real time clock scsi SCSI info (see text) slabinfo Slab pool info + softirqs softirq usage stat Overall statistics swaps Swap space utilization sys See chapter 2 @@ -597,6 +736,25 @@ on the kind of area : 0xffffffffa0017000-0xffffffffa0022000 45056 sys_init_module+0xc27/0x1d00 ... pages=10 vmalloc N0=10 +.............................................................................. + +softirqs: + +Provides counts of softirq handlers serviced since boot time, for each cpu. + +> cat /proc/softirqs + CPU0 CPU1 CPU2 CPU3 + HI: 0 0 0 0 + TIMER: 27166 27120 27097 27034 + NET_TX: 0 0 0 17 + NET_RX: 42 0 0 39 + BLOCK: 0 0 107 1121 + TASKLET: 0 0 0 290 + SCHED: 27035 26983 26971 26746 + HRTIMER: 0 0 0 0 + RCU: 1678 1769 2178 2250 + + 1.3 IDE devices in /proc/ide ---------------------------- @@ -614,10 +772,10 @@ IDE devices: More detailed information can be found in the controller specific subdirectories. These are named ide0, ide1 and so on. Each of these -directories contains the files shown in table 1-5. +directories contains the files shown in table 1-6. -Table 1-5: IDE controller info in /proc/ide/ide? +Table 1-6: IDE controller info in /proc/ide/ide? .............................................................................. File Content channel IDE channel (0 or 1) @@ -627,11 +785,11 @@ Table 1-5: IDE controller info in /proc/ide/ide? .............................................................................. Each device connected to a controller has a separate subdirectory in the -controllers directory. The files listed in table 1-6 are contained in these +controllers directory. The files listed in table 1-7 are contained in these directories. -Table 1-6: IDE device information +Table 1-7: IDE device information .............................................................................. File Content cache The cache @@ -673,12 +831,12 @@ the drive parameters: 1.4 Networking info in /proc/net -------------------------------- -The subdirectory /proc/net follows the usual pattern. Table 1-6 shows the +The subdirectory /proc/net follows the usual pattern. Table 1-8 shows the additional values you get for IP version 6 if you configure the kernel to -support this. Table 1-7 lists the files and their meaning. +support this. Table 1-9 lists the files and their meaning. -Table 1-6: IPv6 info in /proc/net +Table 1-8: IPv6 info in /proc/net .............................................................................. File Content udp6 UDP sockets (IPv6) @@ -693,7 +851,7 @@ Table 1-6: IPv6 info in /proc/net .............................................................................. -Table 1-7: Network info in /proc/net +Table 1-9: Network info in /proc/net .............................................................................. File Content arp Kernel ARP table @@ -817,10 +975,10 @@ The directory /proc/parport contains information about the parallel ports of your system. It has one subdirectory for each port, named after the port number (0,1,2,...). -These directories contain the four files shown in Table 1-8. +These directories contain the four files shown in Table 1-10. -Table 1-8: Files in /proc/parport +Table 1-10: Files in /proc/parport .............................................................................. File Content autoprobe Any IEEE-1284 device ID information that has been acquired. @@ -838,10 +996,10 @@ Table 1-8: Files in /proc/parport Information about the available and actually used tty's can be found in the directory /proc/tty.You'll find entries for drivers and line disciplines in -this directory, as shown in Table 1-9. +this directory, as shown in Table 1-11. -Table 1-9: Files in /proc/tty +Table 1-11: Files in /proc/tty .............................................................................. File Content drivers list of drivers and their usage @@ -883,6 +1041,7 @@ since the system first booted. For a quick look, simply cat the file: processes 2915 procs_running 1 procs_blocked 0 + softirq 183433 0 21755 12 39 1137 231 21459 2263 The very first "cpu" line aggregates the numbers in all of the other "cpuN" lines. These numbers identify the amount of time the CPU has spent performing @@ -918,6 +1077,11 @@ CPUs. The "procs_blocked" line gives the number of processes currently blocked, waiting for I/O to complete. +The "softirq" line gives counts of softirqs serviced since boot time, for each +of the possible system softirqs. The first column is the total of all +softirqs serviced; each subsequent column is the total for that particular +softirq. + 1.9 Ext4 file system parameters ------------------------------ @@ -926,9 +1090,9 @@ Information about mounted ext4 file systems can be found in /proc/fs/ext4. Each mounted filesystem will have a directory in /proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or /proc/fs/ext4/dm-0). The files in each per-device directory are shown -in Table 1-10, below. +in Table 1-12, below. -Table 1-10: Files in /proc/fs/ext4/<devname> +Table 1-12: Files in /proc/fs/ext4/<devname> .............................................................................. File Content mb_groups details of multiblock allocator buddy cache of free blocks @@ -1003,11 +1167,13 @@ CHAPTER 3: PER-PROCESS PARAMETERS 3.1 /proc/<pid>/oom_adj - Adjust the oom-killer score ------------------------------------------------------ -This file can be used to adjust the score used to select which processes -should be killed in an out-of-memory situation. Giving it a high score will -increase the likelihood of this process being killed by the oom-killer. Valid -values are in the range -16 to +15, plus the special value -17, which disables -oom-killing altogether for this process. +This file can be used to adjust the score used to select which processes should +be killed in an out-of-memory situation. The oom_adj value is a characteristic +of the task's mm, so all threads that share an mm with pid will have the same +oom_adj value. A high value will increase the likelihood of this process being +killed by the oom-killer. Valid values are in the range -16 to +15 as +explained below and a special value of -17, which disables oom-killing +altogether for threads sharing pid's mm. The process to be killed in an out-of-memory situation is selected among all others based on its badness score. This value equals the original memory size of the process @@ -1021,6 +1187,9 @@ the parent's score if they do not share the same memory. Thus forking servers are the prime candidates to be killed. Having only one 'hungry' child will make parent less preferable than the child. +/proc/<pid>/oom_adj cannot be changed for kthreads since they are immune from +oom-killing already. + /proc/<pid>/oom_score shows process' current badness score. The following heuristics are then applied: diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt index 5147be5e13cd..b58b84b50fa2 100644 --- a/Documentation/filesystems/vfat.txt +++ b/Documentation/filesystems/vfat.txt @@ -132,6 +132,11 @@ rodir -- FAT has the ATTR_RO (read-only) attribute. On Windows, If you want to use ATTR_RO as read-only flag even for the directory, set this option. +errors=panic|continue|remount-ro + -- specify FAT behavior on critical errors: panic, continue + without doing anything or remount the partition in + read-only mode (default behavior). + <bool>: 0,1,yes,no,true,false TODO diff --git a/Documentation/firmware_class/README b/Documentation/firmware_class/README index c3480aa66ba8..7eceaff63f5f 100644 --- a/Documentation/firmware_class/README +++ b/Documentation/firmware_class/README @@ -77,7 +77,8 @@ seconds for the whole load operation. - request_firmware_nowait() is also provided for convenience in - non-user contexts. + user contexts to request firmware asynchronously, but can't be called + in atomic contexts. about in-kernel persistence: diff --git a/Documentation/gcov.txt b/Documentation/gcov.txt new file mode 100644 index 000000000000..e716aadb3a33 --- /dev/null +++ b/Documentation/gcov.txt @@ -0,0 +1,246 @@ +Using gcov with the Linux kernel +================================ + +1. Introduction +2. Preparation +3. Customization +4. Files +5. Modules +6. Separated build and test machines +7. Troubleshooting +Appendix A: sample script: gather_on_build.sh +Appendix B: sample script: gather_on_test.sh + + +1. Introduction +=============== + +gcov profiling kernel support enables the use of GCC's coverage testing +tool gcov [1] with the Linux kernel. Coverage data of a running kernel +is exported in gcov-compatible format via the "gcov" debugfs directory. +To get coverage data for a specific file, change to the kernel build +directory and use gcov with the -o option as follows (requires root): + +# cd /tmp/linux-out +# gcov -o /sys/kernel/debug/gcov/tmp/linux-out/kernel spinlock.c + +This will create source code files annotated with execution counts +in the current directory. In addition, graphical gcov front-ends such +as lcov [2] can be used to automate the process of collecting data +for the entire kernel and provide coverage overviews in HTML format. + +Possible uses: + +* debugging (has this line been reached at all?) +* test improvement (how do I change my test to cover these lines?) +* minimizing kernel configurations (do I need this option if the + associated code is never run?) + +-- + +[1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html +[2] http://ltp.sourceforge.net/coverage/lcov.php + + +2. Preparation +============== + +Configure the kernel with: + + CONFIG_DEBUGFS=y + CONFIG_GCOV_KERNEL=y + +and to get coverage data for the entire kernel: + + CONFIG_GCOV_PROFILE_ALL=y + +Note that kernels compiled with profiling flags will be significantly +larger and run slower. Also CONFIG_GCOV_PROFILE_ALL may not be supported +on all architectures. + +Profiling data will only become accessible once debugfs has been +mounted: + + mount -t debugfs none /sys/kernel/debug + + +3. Customization +================ + +To enable profiling for specific files or directories, add a line +similar to the following to the respective kernel Makefile: + + For a single file (e.g. main.o): + GCOV_PROFILE_main.o := y + + For all files in one directory: + GCOV_PROFILE := y + +To exclude files from being profiled even when CONFIG_GCOV_PROFILE_ALL +is specified, use: + + GCOV_PROFILE_main.o := n + and: + GCOV_PROFILE := n + +Only files which are linked to the main kernel image or are compiled as +kernel modules are supported by this mechanism. + + +4. Files +======== + +The gcov kernel support creates the following files in debugfs: + + /sys/kernel/debug/gcov + Parent directory for all gcov-related files. + + /sys/kernel/debug/gcov/reset + Global reset file: resets all coverage data to zero when + written to. + + /sys/kernel/debug/gcov/path/to/compile/dir/file.gcda + The actual gcov data file as understood by the gcov + tool. Resets file coverage data to zero when written to. + + /sys/kernel/debug/gcov/path/to/compile/dir/file.gcno + Symbolic link to a static data file required by the gcov + tool. This file is generated by gcc when compiling with + option -ftest-coverage. + + +5. Modules +========== + +Kernel modules may contain cleanup code which is only run during +module unload time. The gcov mechanism provides a means to collect +coverage data for such code by keeping a copy of the data associated +with the unloaded module. This data remains available through debugfs. +Once the module is loaded again, the associated coverage counters are +initialized with the data from its previous instantiation. + +This behavior can be deactivated by specifying the gcov_persist kernel +parameter: + + gcov_persist=0 + +At run-time, a user can also choose to discard data for an unloaded +module by writing to its data file or the global reset file. + + +6. Separated build and test machines +==================================== + +The gcov kernel profiling infrastructure is designed to work out-of-the +box for setups where kernels are built and run on the same machine. In +cases where the kernel runs on a separate machine, special preparations +must be made, depending on where the gcov tool is used: + +a) gcov is run on the TEST machine + +The gcov tool version on the test machine must be compatible with the +gcc version used for kernel build. Also the following files need to be +copied from build to test machine: + +from the source tree: + - all C source files + headers + +from the build tree: + - all C source files + headers + - all .gcda and .gcno files + - all links to directories + +It is important to note that these files need to be placed into the +exact same file system location on the test machine as on the build +machine. If any of the path components is symbolic link, the actual +directory needs to be used instead (due to make's CURDIR handling). + +b) gcov is run on the BUILD machine + +The following files need to be copied after each test case from test +to build machine: + +from the gcov directory in sysfs: + - all .gcda files + - all links to .gcno files + +These files can be copied to any location on the build machine. gcov +must then be called with the -o option pointing to that directory. + +Example directory setup on the build machine: + + /tmp/linux: kernel source tree + /tmp/out: kernel build directory as specified by make O= + /tmp/coverage: location of the files copied from the test machine + + [user@build] cd /tmp/out + [user@build] gcov -o /tmp/coverage/tmp/out/init main.c + + +7. Troubleshooting +================== + +Problem: Compilation aborts during linker step. +Cause: Profiling flags are specified for source files which are not + linked to the main kernel or which are linked by a custom + linker procedure. +Solution: Exclude affected source files from profiling by specifying + GCOV_PROFILE := n or GCOV_PROFILE_basename.o := n in the + corresponding Makefile. + + +Appendix A: gather_on_build.sh +============================== + +Sample script to gather coverage meta files on the build machine +(see 6a): + +#!/bin/bash + +KSRC=$1 +KOBJ=$2 +DEST=$3 + +if [ -z "$KSRC" ] || [ -z "$KOBJ" ] || [ -z "$DEST" ]; then + echo "Usage: $0 <ksrc directory> <kobj directory> <output.tar.gz>" >&2 + exit 1 +fi + +KSRC=$(cd $KSRC; printf "all:\n\t@echo \${CURDIR}\n" | make -f -) +KOBJ=$(cd $KOBJ; printf "all:\n\t@echo \${CURDIR}\n" | make -f -) + +find $KSRC $KOBJ \( -name '*.gcno' -o -name '*.[ch]' -o -type l \) -a \ + -perm /u+r,g+r | tar cfz $DEST -P -T - + +if [ $? -eq 0 ] ; then + echo "$DEST successfully created, copy to test system and unpack with:" + echo " tar xfz $DEST -P" +else + echo "Could not create file $DEST" +fi + + +Appendix B: gather_on_test.sh +============================= + +Sample script to gather coverage data files on the test machine +(see 6b): + +#!/bin/bash + +DEST=$1 +GCDA=/sys/kernel/debug/gcov + +if [ -z "$DEST" ] ; then + echo "Usage: $0 <output.tar.gz>" >&2 + exit 1 +fi + +find $GCDA -name '*.gcno' -o -name '*.gcda' | tar cfz $DEST -T - + +if [ $? -eq 0 ] ; then + echo "$DEST successfully created, copy to build system and unpack with:" + echo " tar xfz $DEST" +else + echo "Could not create file $DEST" +fi diff --git a/Documentation/hwmon/f71882fg b/Documentation/hwmon/f71882fg index a8321267b5b6..bee4c30bc1e2 100644 --- a/Documentation/hwmon/f71882fg +++ b/Documentation/hwmon/f71882fg @@ -2,14 +2,18 @@ Kernel driver f71882fg ====================== Supported chips: - * Fintek F71882FG and F71883FG - Prefix: 'f71882fg' + * Fintek F71858FG + Prefix: 'f71858fg' Addresses scanned: none, address read from Super I/O config space Datasheet: Available from the Fintek website * Fintek F71862FG and F71863FG Prefix: 'f71862fg' Addresses scanned: none, address read from Super I/O config space Datasheet: Available from the Fintek website + * Fintek F71882FG and F71883FG + Prefix: 'f71882fg' + Addresses scanned: none, address read from Super I/O config space + Datasheet: Available from the Fintek website * Fintek F8000 Prefix: 'f8000' Addresses scanned: none, address read from Super I/O config space @@ -66,13 +70,13 @@ printed when loading the driver. Three different fan control modes are supported; the mode number is written to the pwm#_enable file. Note that not all modes are supported on all -chips, and some modes may only be available in RPM / PWM mode on the F8000. +chips, and some modes may only be available in RPM / PWM mode. Writing an unsupported mode will result in an invalid parameter error. * 1: Manual mode You ask for a specific PWM duty cycle / DC voltage or a specific % of fan#_full_speed by writing to the pwm# file. This mode is only - available on the F8000 if the fan channel is in RPM mode. + available on the F71858FG / F8000 if the fan channel is in RPM mode. * 2: Normal auto mode You can define a number of temperature/fan speed trip points, which % the diff --git a/Documentation/hwmon/ibmaem b/Documentation/hwmon/ibmaem index e98bdfea3467..1e0d59e000b4 100644 --- a/Documentation/hwmon/ibmaem +++ b/Documentation/hwmon/ibmaem @@ -7,7 +7,7 @@ henceforth as AEM. Supported systems: * Any recent IBM System X server with AEM support. This includes the x3350, x3550, x3650, x3655, x3755, x3850 M2, - x3950 M2, and certain HS2x/LS2x/QS2x blades. The IPMI host interface + x3950 M2, and certain HC10/HS2x/LS2x/QS2x blades. The IPMI host interface driver ("ipmi-si") needs to be loaded for this driver to do anything. Prefix: 'ibmaem' Datasheet: Not available diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index 004ee161721e..dcbd502c8792 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface @@ -70,6 +70,7 @@ are interpreted as 0! For more on how written strings are interpreted see the [0-*] denotes any positive number starting from 0 [1-*] denotes any positive number starting from 1 RO read only value +WO write only value RW read/write value Read/write values may be read-only for some chips, depending on the @@ -295,6 +296,24 @@ temp[1-*]_label Suggested temperature channel label. user-space. RO +temp[1-*]_lowest + Historical minimum temperature + Unit: millidegree Celsius + RO + +temp[1-*]_highest + Historical maximum temperature + Unit: millidegree Celsius + RO + +temp[1-*]_reset_history + Reset temp_lowest and temp_highest + WO + +temp_reset_history + Reset temp_lowest and temp_highest for all sensors + WO + Some chips measure temperature using external thermistors and an ADC, and report the temperature measurement as a voltage. Converting this voltage back to a temperature (or the other way around for limits) requires diff --git a/Documentation/hwmon/tmp401 b/Documentation/hwmon/tmp401 new file mode 100644 index 000000000000..9fc447249212 --- /dev/null +++ b/Documentation/hwmon/tmp401 @@ -0,0 +1,42 @@ +Kernel driver tmp401 +==================== + +Supported chips: + * Texas Instruments TMP401 + Prefix: 'tmp401' + Addresses scanned: I2C 0x4c + Datasheet: http://focus.ti.com/docs/prod/folders/print/tmp401.html + * Texas Instruments TMP411 + Prefix: 'tmp411' + Addresses scanned: I2C 0x4c + Datasheet: http://focus.ti.com/docs/prod/folders/print/tmp411.html + +Authors: + Hans de Goede <hdegoede@redhat.com> + Andre Prendel <andre.prendel@gmx.de> + +Description +----------- + +This driver implements support for Texas Instruments TMP401 and +TMP411 chips. These chips implements one remote and one local +temperature sensor. Temperature is measured in degrees +Celsius. Resolution of the remote sensor is 0.0625 degree. Local +sensor resolution can be set to 0.5, 0.25, 0.125 or 0.0625 degree (not +supported by the driver so far, so using the default resolution of 0.5 +degree). + +The driver provides the common sysfs-interface for temperatures (see +/Documentation/hwmon/sysfs-interface under Temperatures). + +The TMP411 chip is compatible with TMP401. It provides some additional +features. + +* Minimum and Maximum temperature measured since power-on, chip-reset + + Exported via sysfs attributes tempX_lowest and tempX_highest. + +* Reset of historical minimum/maximum temperature measurements + + Exported via sysfs attribute temp_reset_history. Writing 1 to this + file triggers a reset. diff --git a/Documentation/hwmon/w83627ehf b/Documentation/hwmon/w83627ehf index b6eb59384bb3..02b74899edaf 100644 --- a/Documentation/hwmon/w83627ehf +++ b/Documentation/hwmon/w83627ehf @@ -12,6 +12,10 @@ Supported chips: Addresses scanned: ISA address retrieved from Super I/O registers Datasheet: http://www.nuvoton.com.tw/NR/rdonlyres/7885623D-A487-4CF9-A47F-30C5F73D6FE6/0/W83627DHG.pdf + * Winbond W83627DHG-P + Prefix: 'w83627dhg' + Addresses scanned: ISA address retrieved from Super I/O registers + Datasheet: not available * Winbond W83667HG Prefix: 'w83667hg' Addresses scanned: ISA address retrieved from Super I/O registers @@ -28,8 +32,8 @@ Description ----------- This driver implements support for the Winbond W83627EHF, W83627EHG, -W83627DHG and W83667HG super I/O chips. We will refer to them collectively -as Winbond chips. +W83627DHG, W83627DHG-P and W83667HG super I/O chips. We will refer to them +collectively as Winbond chips. The chips implement three temperature sensors, five fan rotation speed sensors, ten analog voltage sensors (only nine for the 627DHG), one @@ -135,3 +139,6 @@ done in the driver for all register addresses. The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and the ICH8 southbridge gets that data via PECI from the DHG, so that the southbridge drives the fans. And the DHG supports SST, a one-wire serial bus. + +The DHG-P has an additional automatic fan speed control mode named Smart Fan +(TM) III+. This mode is not yet supported by the driver. diff --git a/Documentation/i2c/busses/i2c-viapro b/Documentation/i2c/busses/i2c-viapro index 22efedf60c87..2e758b0e9456 100644 --- a/Documentation/i2c/busses/i2c-viapro +++ b/Documentation/i2c/busses/i2c-viapro @@ -19,6 +19,9 @@ Supported adapters: * VIA Technologies, Inc. VX800/VX820 Datasheet: available on http://linux.via.com.tw + * VIA Technologies, Inc. VX855/VX875 + Datasheet: Availability unknown + Authors: Kyösti Mälkki <kmalkki@cc.hut.fi>, Mark D. Studebaker <mdsxyz123@yahoo.com>, @@ -53,6 +56,7 @@ Your lspci -n listing must show one of these : device 1106:3287 (VT8251) device 1106:8324 (CX700) device 1106:8353 (VX800/VX820) + device 1106:8409 (VX855/VX875) If none of these show up, you should look in the BIOS for settings like enable ACPI / SMBus or even USB. diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices index b55ce57a84db..c740b7b41088 100644 --- a/Documentation/i2c/instantiating-devices +++ b/Documentation/i2c/instantiating-devices @@ -165,3 +165,47 @@ was done there. Two significant differences are: Once again, method 3 should be avoided wherever possible. Explicit device instantiation (methods 1 and 2) is much preferred for it is safer and faster. + + +Method 4: Instantiate from user-space +------------------------------------- + +In general, the kernel should know which I2C devices are connected and +what addresses they live at. However, in certain cases, it does not, so a +sysfs interface was added to let the user provide the information. This +interface is made of 2 attribute files which are created in every I2C bus +directory: new_device and delete_device. Both files are write only and you +must write the right parameters to them in order to properly instantiate, +respectively delete, an I2C device. + +File new_device takes 2 parameters: the name of the I2C device (a string) +and the address of the I2C device (a number, typically expressed in +hexadecimal starting with 0x, but can also be expressed in decimal.) + +File delete_device takes a single parameter: the address of the I2C +device. As no two devices can live at the same address on a given I2C +segment, the address is sufficient to uniquely identify the device to be +deleted. + +Example: +# echo eeprom 0x50 > /sys/class/i2c-adapter/i2c-3/new_device + +While this interface should only be used when in-kernel device declaration +can't be done, there is a variety of cases where it can be helpful: +* The I2C driver usually detects devices (method 3 above) but the bus + segment your device lives on doesn't have the proper class bit set and + thus detection doesn't trigger. +* The I2C driver usually detects devices, but your device lives at an + unexpected address. +* The I2C driver usually detects devices, but your device is not detected, + either because the detection routine is too strict, or because your + device is not officially supported yet but you know it is compatible. +* You are developing a driver on a test board, where you soldered the I2C + device yourself. + +This interface is a replacement for the force_* module parameters some I2C +drivers implement. Being implemented in i2c-core rather than in each +device driver individually, it is much more efficient, and also has the +advantage that you do not have to reload the driver to change a setting. +You can also instantiate the device before the driver is loaded or even +available, and you don't need to know what driver the device needs. diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients index c1a06f989cf7..7860aafb483d 100644 --- a/Documentation/i2c/writing-clients +++ b/Documentation/i2c/writing-clients @@ -126,19 +126,9 @@ different) configuration information, as do drivers handling chip variants that can't be distinguished by protocol probing, or which need some board specific information to operate correctly. -Accordingly, the I2C stack now has two models for associating I2C devices -with their drivers: the original "legacy" model, and a newer one that's -fully compatible with the Linux 2.6 driver model. These models do not mix, -since the "legacy" model requires drivers to create "i2c_client" device -objects after SMBus style probing, while the Linux driver model expects -drivers to be given such device objects in their probe() routines. -The legacy model is deprecated now and will soon be removed, so we no -longer document it here. - - -Standard Driver Model Binding ("New Style") -------------------------------------------- +Device/Driver Binding +--------------------- System infrastructure, typically board-specific initialization code or boot firmware, reports what I2C devices exist. For example, there may be @@ -201,7 +191,7 @@ a given I2C bus. This is for example the case of hardware monitoring devices on a PC's SMBus. In that case, you may want to let your driver detect supported devices automatically. This is how the legacy model was working, and is now available as an extension to the standard -driver model (so that we can finally get rid of the legacy model.) +driver model. You simply have to define a detect callback which will attempt to identify supported devices (returning 0 for supported ones and -ENODEV diff --git a/Documentation/input/input.txt b/Documentation/input/input.txt index 686ee9932dff..b93c08442e3c 100644 --- a/Documentation/input/input.txt +++ b/Documentation/input/input.txt @@ -278,7 +278,7 @@ struct input_event { }; 'time' is the timestamp, it returns the time at which the event happened. -Type is for example EV_REL for relative moment, REL_KEY for a keypress or +Type is for example EV_REL for relative moment, EV_KEY for a keypress or release. More types are defined in include/linux/input.h. 'code' is event code, for example REL_X or KEY_BACKSPACE, again a complete diff --git a/Documentation/input/rotary-encoder.txt b/Documentation/input/rotary-encoder.txt index 435102a26d96..3a6aec40c0b0 100644 --- a/Documentation/input/rotary-encoder.txt +++ b/Documentation/input/rotary-encoder.txt @@ -67,7 +67,12 @@ data with it. struct rotary_encoder_platform_data is declared in include/linux/rotary-encoder.h and needs to be filled with the number of steps the encoder has and can carry information about externally inverted -signals (because of used invertig buffer or other reasons). +signals (because of an inverting buffer or other reasons). The encoder +can be set up to deliver input information as either an absolute or relative +axes. For relative axes the input event returns +/-1 for each step. For +absolute axes the position of the encoder can either roll over between zero +and the number of steps or will clamp at the maximum and zero depending on +the configuration. Because GPIO to IRQ mapping is platform specific, this information must be given in seperately to the driver. See the example below. @@ -85,6 +90,8 @@ be given in seperately to the driver. See the example below. static struct rotary_encoder_platform_data my_rotary_encoder_info = { .steps = 24, .axis = ABS_X, + .relative_axis = false, + .rollover = false, .gpio_a = GPIO_ROTARY_A, .gpio_b = GPIO_ROTARY_B, .inverted_a = 0, diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 1f779a25c703..7bb0d934b6d8 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -149,6 +149,8 @@ Code Seq# Include File Comments 'p' 40-7F linux/nvram.h 'p' 80-9F user-space parport <mailto:tim@cyberelk.net> +'p' a1-a4 linux/pps.h LinuxPPS + <mailto:giometti@linux.it> 'q' 00-1F linux/serio.h 'q' 80-FF Internet PhoneJACK, Internet LineJACK <http://www.quicknet.net> diff --git a/Documentation/ja_JP/SubmitChecklist b/Documentation/ja_JP/SubmitChecklist index 6c42e071d723..2df4576f1173 100644 --- a/Documentation/ja_JP/SubmitChecklist +++ b/Documentation/ja_JP/SubmitChecklist @@ -75,7 +75,7 @@ Linux カーネルパッチ投稿者向けチェックリスト ビルドした上、動作確認を行ってください。 14: もしパッチがディスクのI/O性能などに影響を与えるようであれば、 - 'CONFIG_LBD'オプションを有効にした場合と無効にした場合の両方で + 'CONFIG_LBDAF'オプションを有効にした場合と無効にした場合の両方で テストを実施してみてください。 15: lockdepの機能を全て有効にした上で、全てのコードパスを評価してください。 diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 5f66ba295c5d..08def8deb5f5 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -48,6 +48,7 @@ parameter is applicable: EFI EFI Partitioning (GPT) is enabled EIDE EIDE/ATAPI support is enabled. FB The frame buffer device is enabled. + GCOV GCOV profiling is enabled. HW Appropriate hardware is enabled. IA-64 IA-64 architecture is enabled. IMA Integrity measurement architecture is enabled. @@ -491,6 +492,13 @@ and is between 256 and 4096 characters. It is defined in the file Also note the kernel might malfunction if you disable some critical bits. + cmo_free_hint= [PPC] Format: { yes | no } + Specify whether pages are marked as being inactive + when they are freed. This is used in CMO environments + to determine OS memory pressure for page stealing by + a hypervisor. + Default: yes + code_bytes [X86] How many bytes of object code to print in an oops report. Range: 0 - 8192 @@ -539,6 +547,10 @@ and is between 256 and 4096 characters. It is defined in the file console=brl,ttyS0 For now, only VisioBraille is supported. + consoleblank= [KNL] The console blank (screen saver) timeout in + seconds. Defaults to 10*60 = 10mins. A value of 0 + disables the blank timer. + coredump_filter= [KNL] Change the default value for /proc/<pid>/coredump_filter. @@ -785,6 +797,12 @@ and is between 256 and 4096 characters. It is defined in the file Format: off | on default: on + gcov_persist= [GCOV] When non-zero (default), profiling data for + kernel modules is saved and remains accessible via + debugfs, even when the module is unloaded/reloaded. + When zero, profiling data is discarded and associated + debugfs files are removed at module unload time. + gdth= [HW,SCSI] See header of drivers/scsi/gdth.c. diff --git a/Documentation/kmemcheck.txt b/Documentation/kmemcheck.txt new file mode 100644 index 000000000000..363044609dad --- /dev/null +++ b/Documentation/kmemcheck.txt @@ -0,0 +1,773 @@ +GETTING STARTED WITH KMEMCHECK +============================== + +Vegard Nossum <vegardno@ifi.uio.no> + + +Contents +======== +0. Introduction +1. Downloading +2. Configuring and compiling +3. How to use +3.1. Booting +3.2. Run-time enable/disable +3.3. Debugging +3.4. Annotating false positives +4. Reporting errors +5. Technical description + + +0. Introduction +=============== + +kmemcheck is a debugging feature for the Linux Kernel. More specifically, it +is a dynamic checker that detects and warns about some uses of uninitialized +memory. + +Userspace programmers might be familiar with Valgrind's memcheck. The main +difference between memcheck and kmemcheck is that memcheck works for userspace +programs only, and kmemcheck works for the kernel only. The implementations +are of course vastly different. Because of this, kmemcheck is not as accurate +as memcheck, but it turns out to be good enough in practice to discover real +programmer errors that the compiler is not able to find through static +analysis. + +Enabling kmemcheck on a kernel will probably slow it down to the extent that +the machine will not be usable for normal workloads such as e.g. an +interactive desktop. kmemcheck will also cause the kernel to use about twice +as much memory as normal. For this reason, kmemcheck is strictly a debugging +feature. + + +1. Downloading +============== + +kmemcheck can only be downloaded using git. If you want to write patches +against the current code, you should use the kmemcheck development branch of +the tip tree. It is also possible to use the linux-next tree, which also +includes the latest version of kmemcheck. + +Assuming that you've already cloned the linux-2.6.git repository, all you +have to do is add the -tip tree as a remote, like this: + + $ git remote add tip git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git + +To actually download the tree, fetch the remote: + + $ git fetch tip + +And to check out a new local branch with the kmemcheck code: + + $ git checkout -b kmemcheck tip/kmemcheck + +General instructions for the -tip tree can be found here: +http://people.redhat.com/mingo/tip.git/readme.txt + + +2. Configuring and compiling +============================ + +kmemcheck only works for the x86 (both 32- and 64-bit) platform. A number of +configuration variables must have specific settings in order for the kmemcheck +menu to even appear in "menuconfig". These are: + + o CONFIG_CC_OPTIMIZE_FOR_SIZE=n + + This option is located under "General setup" / "Optimize for size". + + Without this, gcc will use certain optimizations that usually lead to + false positive warnings from kmemcheck. An example of this is a 16-bit + field in a struct, where gcc may load 32 bits, then discard the upper + 16 bits. kmemcheck sees only the 32-bit load, and may trigger a + warning for the upper 16 bits (if they're uninitialized). + + o CONFIG_SLAB=y or CONFIG_SLUB=y + + This option is located under "General setup" / "Choose SLAB + allocator". + + o CONFIG_FUNCTION_TRACER=n + + This option is located under "Kernel hacking" / "Tracers" / "Kernel + Function Tracer" + + When function tracing is compiled in, gcc emits a call to another + function at the beginning of every function. This means that when the + page fault handler is called, the ftrace framework will be called + before kmemcheck has had a chance to handle the fault. If ftrace then + modifies memory that was tracked by kmemcheck, the result is an + endless recursive page fault. + + o CONFIG_DEBUG_PAGEALLOC=n + + This option is located under "Kernel hacking" / "Debug page memory + allocations". + +In addition, I highly recommend turning on CONFIG_DEBUG_INFO=y. This is also +located under "Kernel hacking". With this, you will be able to get line number +information from the kmemcheck warnings, which is extremely valuable in +debugging a problem. This option is not mandatory, however, because it slows +down the compilation process and produces a much bigger kernel image. + +Now the kmemcheck menu should be visible (under "Kernel hacking" / "kmemcheck: +trap use of uninitialized memory"). Here follows a description of the +kmemcheck configuration variables: + + o CONFIG_KMEMCHECK + + This must be enabled in order to use kmemcheck at all... + + o CONFIG_KMEMCHECK_[DISABLED | ENABLED | ONESHOT]_BY_DEFAULT + + This option controls the status of kmemcheck at boot-time. "Enabled" + will enable kmemcheck right from the start, "disabled" will boot the + kernel as normal (but with the kmemcheck code compiled in, so it can + be enabled at run-time after the kernel has booted), and "one-shot" is + a special mode which will turn kmemcheck off automatically after + detecting the first use of uninitialized memory. + + If you are using kmemcheck to actively debug a problem, then you + probably want to choose "enabled" here. + + The one-shot mode is mostly useful in automated test setups because it + can prevent floods of warnings and increase the chances of the machine + surviving in case something is really wrong. In other cases, the one- + shot mode could actually be counter-productive because it would turn + itself off at the very first error -- in the case of a false positive + too -- and this would come in the way of debugging the specific + problem you were interested in. + + If you would like to use your kernel as normal, but with a chance to + enable kmemcheck in case of some problem, it might be a good idea to + choose "disabled" here. When kmemcheck is disabled, most of the run- + time overhead is not incurred, and the kernel will be almost as fast + as normal. + + o CONFIG_KMEMCHECK_QUEUE_SIZE + + Select the maximum number of error reports to store in an internal + (fixed-size) buffer. Since errors can occur virtually anywhere and in + any context, we need a temporary storage area which is guaranteed not + to generate any other page faults when accessed. The queue will be + emptied as soon as a tasklet may be scheduled. If the queue is full, + new error reports will be lost. + + The default value of 64 is probably fine. If some code produces more + than 64 errors within an irqs-off section, then the code is likely to + produce many, many more, too, and these additional reports seldom give + any more information (the first report is usually the most valuable + anyway). + + This number might have to be adjusted if you are not using serial + console or similar to capture the kernel log. If you are using the + "dmesg" command to save the log, then getting a lot of kmemcheck + warnings might overflow the kernel log itself, and the earlier reports + will get lost in that way instead. Try setting this to 10 or so on + such a setup. + + o CONFIG_KMEMCHECK_SHADOW_COPY_SHIFT + + Select the number of shadow bytes to save along with each entry of the + error-report queue. These bytes indicate what parts of an allocation + are initialized, uninitialized, etc. and will be displayed when an + error is detected to help the debugging of a particular problem. + + The number entered here is actually the logarithm of the number of + bytes that will be saved. So if you pick for example 5 here, kmemcheck + will save 2^5 = 32 bytes. + + The default value should be fine for debugging most problems. It also + fits nicely within 80 columns. + + o CONFIG_KMEMCHECK_PARTIAL_OK + + This option (when enabled) works around certain GCC optimizations that + produce 32-bit reads from 16-bit variables where the upper 16 bits are + thrown away afterwards. + + The default value (enabled) is recommended. This may of course hide + some real errors, but disabling it would probably produce a lot of + false positives. + + o CONFIG_KMEMCHECK_BITOPS_OK + + This option silences warnings that would be generated for bit-field + accesses where not all the bits are initialized at the same time. This + may also hide some real bugs. + + This option is probably obsolete, or it should be replaced with + the kmemcheck-/bitfield-annotations for the code in question. The + default value is therefore fine. + +Now compile the kernel as usual. + + +3. How to use +============= + +3.1. Booting +============ + +First some information about the command-line options. There is only one +option specific to kmemcheck, and this is called "kmemcheck". It can be used +to override the default mode as chosen by the CONFIG_KMEMCHECK_*_BY_DEFAULT +option. Its possible settings are: + + o kmemcheck=0 (disabled) + o kmemcheck=1 (enabled) + o kmemcheck=2 (one-shot mode) + +If SLUB debugging has been enabled in the kernel, it may take precedence over +kmemcheck in such a way that the slab caches which are under SLUB debugging +will not be tracked by kmemcheck. In order to ensure that this doesn't happen +(even though it shouldn't by default), use SLUB's boot option "slub_debug", +like this: slub_debug=- + +In fact, this option may also be used for fine-grained control over SLUB vs. +kmemcheck. For example, if the command line includes "kmemcheck=1 +slub_debug=,dentry", then SLUB debugging will be used only for the "dentry" +slab cache, and with kmemcheck tracking all the other caches. This is advanced +usage, however, and is not generally recommended. + + +3.2. Run-time enable/disable +============================ + +When the kernel has booted, it is possible to enable or disable kmemcheck at +run-time. WARNING: This feature is still experimental and may cause false +positive warnings to appear. Therefore, try not to use this. If you find that +it doesn't work properly (e.g. you see an unreasonable amount of warnings), I +will be happy to take bug reports. + +Use the file /proc/sys/kernel/kmemcheck for this purpose, e.g.: + + $ echo 0 > /proc/sys/kernel/kmemcheck # disables kmemcheck + +The numbers are the same as for the kmemcheck= command-line option. + + +3.3. Debugging +============== + +A typical report will look something like this: + +WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (ffff88003e4a2024) +80000000000000000000000000000000000000000088ffff0000000000000000 + i i i i u u u u i i i i i i i i u u u u u u u u u u u u u u u u + ^ + +Pid: 1856, comm: ntpdate Not tainted 2.6.29-rc5 #264 945P-A +RIP: 0010:[<ffffffff8104ede8>] [<ffffffff8104ede8>] __dequeue_signal+0xc8/0x190 +RSP: 0018:ffff88003cdf7d98 EFLAGS: 00210002 +RAX: 0000000000000030 RBX: ffff88003d4ea968 RCX: 0000000000000009 +RDX: ffff88003e5d6018 RSI: ffff88003e5d6024 RDI: ffff88003cdf7e84 +RBP: ffff88003cdf7db8 R08: ffff88003e5d6000 R09: 0000000000000000 +R10: 0000000000000080 R11: 0000000000000000 R12: 000000000000000e +R13: ffff88003cdf7e78 R14: ffff88003d530710 R15: ffff88003d5a98c8 +FS: 0000000000000000(0000) GS:ffff880001982000(0063) knlGS:00000 +CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 +CR2: ffff88003f806ea0 CR3: 000000003c036000 CR4: 00000000000006a0 +DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 +DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400 + [<ffffffff8104f04e>] dequeue_signal+0x8e/0x170 + [<ffffffff81050bd8>] get_signal_to_deliver+0x98/0x390 + [<ffffffff8100b87d>] do_notify_resume+0xad/0x7d0 + [<ffffffff8100c7b5>] int_signal+0x12/0x17 + [<ffffffffffffffff>] 0xffffffffffffffff + +The single most valuable information in this report is the RIP (or EIP on 32- +bit) value. This will help us pinpoint exactly which instruction that caused +the warning. + +If your kernel was compiled with CONFIG_DEBUG_INFO=y, then all we have to do +is give this address to the addr2line program, like this: + + $ addr2line -e vmlinux -i ffffffff8104ede8 + arch/x86/include/asm/string_64.h:12 + include/asm-generic/siginfo.h:287 + kernel/signal.c:380 + kernel/signal.c:410 + +The "-e vmlinux" tells addr2line which file to look in. IMPORTANT: This must +be the vmlinux of the kernel that produced the warning in the first place! If +not, the line number information will almost certainly be wrong. + +The "-i" tells addr2line to also print the line numbers of inlined functions. +In this case, the flag was very important, because otherwise, it would only +have printed the first line, which is just a call to memcpy(), which could be +called from a thousand places in the kernel, and is therefore not very useful. +These inlined functions would not show up in the stack trace above, simply +because the kernel doesn't load the extra debugging information. This +technique can of course be used with ordinary kernel oopses as well. + +In this case, it's the caller of memcpy() that is interesting, and it can be +found in include/asm-generic/siginfo.h, line 287: + +281 static inline void copy_siginfo(struct siginfo *to, struct siginfo *from) +282 { +283 if (from->si_code < 0) +284 memcpy(to, from, sizeof(*to)); +285 else +286 /* _sigchld is currently the largest know union member */ +287 memcpy(to, from, __ARCH_SI_PREAMBLE_SIZE + sizeof(from->_sifields._sigchld)); +288 } + +Since this was a read (kmemcheck usually warns about reads only, though it can +warn about writes to unallocated or freed memory as well), it was probably the +"from" argument which contained some uninitialized bytes. Following the chain +of calls, we move upwards to see where "from" was allocated or initialized, +kernel/signal.c, line 380: + +359 static void collect_signal(int sig, struct sigpending *list, siginfo_t *info) +360 { +... +367 list_for_each_entry(q, &list->list, list) { +368 if (q->info.si_signo == sig) { +369 if (first) +370 goto still_pending; +371 first = q; +... +377 if (first) { +378 still_pending: +379 list_del_init(&first->list); +380 copy_siginfo(info, &first->info); +381 __sigqueue_free(first); +... +392 } +393 } + +Here, it is &first->info that is being passed on to copy_siginfo(). The +variable "first" was found on a list -- passed in as the second argument to +collect_signal(). We continue our journey through the stack, to figure out +where the item on "list" was allocated or initialized. We move to line 410: + +395 static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, +396 siginfo_t *info) +397 { +... +410 collect_signal(sig, pending, info); +... +414 } + +Now we need to follow the "pending" pointer, since that is being passed on to +collect_signal() as "list". At this point, we've run out of lines from the +"addr2line" output. Not to worry, we just paste the next addresses from the +kmemcheck stack dump, i.e.: + + [<ffffffff8104f04e>] dequeue_signal+0x8e/0x170 + [<ffffffff81050bd8>] get_signal_to_deliver+0x98/0x390 + [<ffffffff8100b87d>] do_notify_resume+0xad/0x7d0 + [<ffffffff8100c7b5>] int_signal+0x12/0x17 + + $ addr2line -e vmlinux -i ffffffff8104f04e ffffffff81050bd8 \ + ffffffff8100b87d ffffffff8100c7b5 + kernel/signal.c:446 + kernel/signal.c:1806 + arch/x86/kernel/signal.c:805 + arch/x86/kernel/signal.c:871 + arch/x86/kernel/entry_64.S:694 + +Remember that since these addresses were found on the stack and not as the +RIP value, they actually point to the _next_ instruction (they are return +addresses). This becomes obvious when we look at the code for line 446: + +422 int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) +423 { +... +431 signr = __dequeue_signal(&tsk->signal->shared_pending, +432 mask, info); +433 /* +434 * itimer signal ? +435 * +436 * itimers are process shared and we restart periodic +437 * itimers in the signal delivery path to prevent DoS +438 * attacks in the high resolution timer case. This is +439 * compliant with the old way of self restarting +440 * itimers, as the SIGALRM is a legacy signal and only +441 * queued once. Changing the restart behaviour to +442 * restart the timer in the signal dequeue path is +443 * reducing the timer noise on heavy loaded !highres +444 * systems too. +445 */ +446 if (unlikely(signr == SIGALRM)) { +... +489 } + +So instead of looking at 446, we should be looking at 431, which is the line +that executes just before 446. Here we see that what we are looking for is +&tsk->signal->shared_pending. + +Our next task is now to figure out which function that puts items on this +"shared_pending" list. A crude, but efficient tool, is git grep: + + $ git grep -n 'shared_pending' kernel/ + ... + kernel/signal.c:828: pending = group ? &t->signal->shared_pending : &t->pending; + kernel/signal.c:1339: pending = group ? &t->signal->shared_pending : &t->pending; + ... + +There were more results, but none of them were related to list operations, +and these were the only assignments. We inspect the line numbers more closely +and find that this is indeed where items are being added to the list: + +816 static int send_signal(int sig, struct siginfo *info, struct task_struct *t, +817 int group) +818 { +... +828 pending = group ? &t->signal->shared_pending : &t->pending; +... +851 q = __sigqueue_alloc(t, GFP_ATOMIC, (sig < SIGRTMIN && +852 (is_si_special(info) || +853 info->si_code >= 0))); +854 if (q) { +855 list_add_tail(&q->list, &pending->list); +... +890 } + +and: + +1309 int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group) +1310 { +.... +1339 pending = group ? &t->signal->shared_pending : &t->pending; +1340 list_add_tail(&q->list, &pending->list); +.... +1347 } + +In the first case, the list element we are looking for, "q", is being returned +from the function __sigqueue_alloc(), which looks like an allocation function. +Let's take a look at it: + +187 static struct sigqueue *__sigqueue_alloc(struct task_struct *t, gfp_t flags, +188 int override_rlimit) +189 { +190 struct sigqueue *q = NULL; +191 struct user_struct *user; +192 +193 /* +194 * We won't get problems with the target's UID changing under us +195 * because changing it requires RCU be used, and if t != current, the +196 * caller must be holding the RCU readlock (by way of a spinlock) and +197 * we use RCU protection here +198 */ +199 user = get_uid(__task_cred(t)->user); +200 atomic_inc(&user->sigpending); +201 if (override_rlimit || +202 atomic_read(&user->sigpending) <= +203 t->signal->rlim[RLIMIT_SIGPENDING].rlim_cur) +204 q = kmem_cache_alloc(sigqueue_cachep, flags); +205 if (unlikely(q == NULL)) { +206 atomic_dec(&user->sigpending); +207 free_uid(user); +208 } else { +209 INIT_LIST_HEAD(&q->list); +210 q->flags = 0; +211 q->user = user; +212 } +213 +214 return q; +215 } + +We see that this function initializes q->list, q->flags, and q->user. It seems +that now is the time to look at the definition of "struct sigqueue", e.g.: + +14 struct sigqueue { +15 struct list_head list; +16 int flags; +17 siginfo_t info; +18 struct user_struct *user; +19 }; + +And, you might remember, it was a memcpy() on &first->info that caused the +warning, so this makes perfect sense. It also seems reasonable to assume that +it is the caller of __sigqueue_alloc() that has the responsibility of filling +out (initializing) this member. + +But just which fields of the struct were uninitialized? Let's look at +kmemcheck's report again: + +WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (ffff88003e4a2024) +80000000000000000000000000000000000000000088ffff0000000000000000 + i i i i u u u u i i i i i i i i u u u u u u u u u u u u u u u u + ^ + +These first two lines are the memory dump of the memory object itself, and the +shadow bytemap, respectively. The memory object itself is in this case +&first->info. Just beware that the start of this dump is NOT the start of the +object itself! The position of the caret (^) corresponds with the address of +the read (ffff88003e4a2024). + +The shadow bytemap dump legend is as follows: + + i - initialized + u - uninitialized + a - unallocated (memory has been allocated by the slab layer, but has not + yet been handed off to anybody) + f - freed (memory has been allocated by the slab layer, but has been freed + by the previous owner) + +In order to figure out where (relative to the start of the object) the +uninitialized memory was located, we have to look at the disassembly. For +that, we'll need the RIP address again: + +RIP: 0010:[<ffffffff8104ede8>] [<ffffffff8104ede8>] __dequeue_signal+0xc8/0x190 + + $ objdump -d --no-show-raw-insn vmlinux | grep -C 8 ffffffff8104ede8: + ffffffff8104edc8: mov %r8,0x8(%r8) + ffffffff8104edcc: test %r10d,%r10d + ffffffff8104edcf: js ffffffff8104ee88 <__dequeue_signal+0x168> + ffffffff8104edd5: mov %rax,%rdx + ffffffff8104edd8: mov $0xc,%ecx + ffffffff8104eddd: mov %r13,%rdi + ffffffff8104ede0: mov $0x30,%eax + ffffffff8104ede5: mov %rdx,%rsi + ffffffff8104ede8: rep movsl %ds:(%rsi),%es:(%rdi) + ffffffff8104edea: test $0x2,%al + ffffffff8104edec: je ffffffff8104edf0 <__dequeue_signal+0xd0> + ffffffff8104edee: movsw %ds:(%rsi),%es:(%rdi) + ffffffff8104edf0: test $0x1,%al + ffffffff8104edf2: je ffffffff8104edf5 <__dequeue_signal+0xd5> + ffffffff8104edf4: movsb %ds:(%rsi),%es:(%rdi) + ffffffff8104edf5: mov %r8,%rdi + ffffffff8104edf8: callq ffffffff8104de60 <__sigqueue_free> + +As expected, it's the "rep movsl" instruction from the memcpy() that causes +the warning. We know about REP MOVSL that it uses the register RCX to count +the number of remaining iterations. By taking a look at the register dump +again (from the kmemcheck report), we can figure out how many bytes were left +to copy: + +RAX: 0000000000000030 RBX: ffff88003d4ea968 RCX: 0000000000000009 + +By looking at the disassembly, we also see that %ecx is being loaded with the +value $0xc just before (ffffffff8104edd8), so we are very lucky. Keep in mind +that this is the number of iterations, not bytes. And since this is a "long" +operation, we need to multiply by 4 to get the number of bytes. So this means +that the uninitialized value was encountered at 4 * (0xc - 0x9) = 12 bytes +from the start of the object. + +We can now try to figure out which field of the "struct siginfo" that was not +initialized. This is the beginning of the struct: + +40 typedef struct siginfo { +41 int si_signo; +42 int si_errno; +43 int si_code; +44 +45 union { +.. +92 } _sifields; +93 } siginfo_t; + +On 64-bit, the int is 4 bytes long, so it must the the union member that has +not been initialized. We can verify this using gdb: + + $ gdb vmlinux + ... + (gdb) p &((struct siginfo *) 0)->_sifields + $1 = (union {...} *) 0x10 + +Actually, it seems that the union member is located at offset 0x10 -- which +means that gcc has inserted 4 bytes of padding between the members si_code +and _sifields. We can now get a fuller picture of the memory dump: + + _----------------------------=> si_code + / _--------------------=> (padding) + | / _------------=> _sifields(._kill._pid) + | | / _----=> _sifields(._kill._uid) + | | | / +-------|-------|-------|-------| +80000000000000000000000000000000000000000088ffff0000000000000000 + i i i i u u u u i i i i i i i i u u u u u u u u u u u u u u u u + +This allows us to realize another important fact: si_code contains the value +0x80. Remember that x86 is little endian, so the first 4 bytes "80000000" are +really the number 0x00000080. With a bit of research, we find that this is +actually the constant SI_KERNEL defined in include/asm-generic/siginfo.h: + +144 #define SI_KERNEL 0x80 /* sent by the kernel from somewhere */ + +This macro is used in exactly one place in the x86 kernel: In send_signal() +in kernel/signal.c: + +816 static int send_signal(int sig, struct siginfo *info, struct task_struct *t, +817 int group) +818 { +... +828 pending = group ? &t->signal->shared_pending : &t->pending; +... +851 q = __sigqueue_alloc(t, GFP_ATOMIC, (sig < SIGRTMIN && +852 (is_si_special(info) || +853 info->si_code >= 0))); +854 if (q) { +855 list_add_tail(&q->list, &pending->list); +856 switch ((unsigned long) info) { +... +865 case (unsigned long) SEND_SIG_PRIV: +866 q->info.si_signo = sig; +867 q->info.si_errno = 0; +868 q->info.si_code = SI_KERNEL; +869 q->info.si_pid = 0; +870 q->info.si_uid = 0; +871 break; +... +890 } + +Not only does this match with the .si_code member, it also matches the place +we found earlier when looking for where siginfo_t objects are enqueued on the +"shared_pending" list. + +So to sum up: It seems that it is the padding introduced by the compiler +between two struct fields that is uninitialized, and this gets reported when +we do a memcpy() on the struct. This means that we have identified a false +positive warning. + +Normally, kmemcheck will not report uninitialized accesses in memcpy() calls +when both the source and destination addresses are tracked. (Instead, we copy +the shadow bytemap as well). In this case, the destination address clearly +was not tracked. We can dig a little deeper into the stack trace from above: + + arch/x86/kernel/signal.c:805 + arch/x86/kernel/signal.c:871 + arch/x86/kernel/entry_64.S:694 + +And we clearly see that the destination siginfo object is located on the +stack: + +782 static void do_signal(struct pt_regs *regs) +783 { +784 struct k_sigaction ka; +785 siginfo_t info; +... +804 signr = get_signal_to_deliver(&info, &ka, regs, NULL); +... +854 } + +And this &info is what eventually gets passed to copy_siginfo() as the +destination argument. + +Now, even though we didn't find an actual error here, the example is still a +good one, because it shows how one would go about to find out what the report +was all about. + + +3.4. Annotating false positives +=============================== + +There are a few different ways to make annotations in the source code that +will keep kmemcheck from checking and reporting certain allocations. Here +they are: + + o __GFP_NOTRACK_FALSE_POSITIVE + + This flag can be passed to kmalloc() or kmem_cache_alloc() (therefore + also to other functions that end up calling one of these) to indicate + that the allocation should not be tracked because it would lead to + a false positive report. This is a "big hammer" way of silencing + kmemcheck; after all, even if the false positive pertains to + particular field in a struct, for example, we will now lose the + ability to find (real) errors in other parts of the same struct. + + Example: + + /* No warnings will ever trigger on accessing any part of x */ + x = kmalloc(sizeof *x, GFP_KERNEL | __GFP_NOTRACK_FALSE_POSITIVE); + + o kmemcheck_bitfield_begin(name)/kmemcheck_bitfield_end(name) and + kmemcheck_annotate_bitfield(ptr, name) + + The first two of these three macros can be used inside struct + definitions to signal, respectively, the beginning and end of a + bitfield. Additionally, this will assign the bitfield a name, which + is given as an argument to the macros. + + Having used these markers, one can later use + kmemcheck_annotate_bitfield() at the point of allocation, to indicate + which parts of the allocation is part of a bitfield. + + Example: + + struct foo { + int x; + + kmemcheck_bitfield_begin(flags); + int flag_a:1; + int flag_b:1; + kmemcheck_bitfield_end(flags); + + int y; + }; + + struct foo *x = kmalloc(sizeof *x); + + /* No warnings will trigger on accessing the bitfield of x */ + kmemcheck_annotate_bitfield(x, flags); + + Note that kmemcheck_annotate_bitfield() can be used even before the + return value of kmalloc() is checked -- in other words, passing NULL + as the first argument is legal (and will do nothing). + + +4. Reporting errors +=================== + +As we have seen, kmemcheck will produce false positive reports. Therefore, it +is not very wise to blindly post kmemcheck warnings to mailing lists and +maintainers. Instead, I encourage maintainers and developers to find errors +in their own code. If you get a warning, you can try to work around it, try +to figure out if it's a real error or not, or simply ignore it. Most +developers know their own code and will quickly and efficiently determine the +root cause of a kmemcheck report. This is therefore also the most efficient +way to work with kmemcheck. + +That said, we (the kmemcheck maintainers) will always be on the lookout for +false positives that we can annotate and silence. So whatever you find, +please drop us a note privately! Kernel configs and steps to reproduce (if +available) are of course a great help too. + +Happy hacking! + + +5. Technical description +======================== + +kmemcheck works by marking memory pages non-present. This means that whenever +somebody attempts to access the page, a page fault is generated. The page +fault handler notices that the page was in fact only hidden, and so it calls +on the kmemcheck code to make further investigations. + +When the investigations are completed, kmemcheck "shows" the page by marking +it present (as it would be under normal circumstances). This way, the +interrupted code can continue as usual. + +But after the instruction has been executed, we should hide the page again, so +that we can catch the next access too! Now kmemcheck makes use of a debugging +feature of the processor, namely single-stepping. When the processor has +finished the one instruction that generated the memory access, a debug +exception is raised. From here, we simply hide the page again and continue +execution, this time with the single-stepping feature turned off. + +kmemcheck requires some assistance from the memory allocator in order to work. +The memory allocator needs to + + 1. Tell kmemcheck about newly allocated pages and pages that are about to + be freed. This allows kmemcheck to set up and tear down the shadow memory + for the pages in question. The shadow memory stores the status of each + byte in the allocation proper, e.g. whether it is initialized or + uninitialized. + + 2. Tell kmemcheck which parts of memory should be marked uninitialized. + There are actually a few more states, such as "not yet allocated" and + "recently freed". + +If a slab cache is set up using the SLAB_NOTRACK flag, it will never return +memory that can take page faults because of kmemcheck. + +If a slab cache is NOT set up using the SLAB_NOTRACK flag, callers can still +request memory with the __GFP_NOTRACK or __GFP_NOTRACK_FALSE_POSITIVE flags. +This does not prevent the page faults from occurring, however, but marks the +object in question as being initialized so that no warnings will ever be +produced for this object. + +Currently, the SLAB and SLUB allocators are supported by kmemcheck. diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 1e7a769a10f9..053037a1fe6d 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt @@ -507,9 +507,9 @@ http://www.linuxsymposium.org/2006/linuxsymposium_procv2.pdf (pages 101-115) Appendix A: The kprobes debugfs interface With recent kernels (> 2.6.20) the list of registered kprobes is visible -under the /debug/kprobes/ directory (assuming debugfs is mounted at /debug). +under the /sys/kernel/debug/kprobes/ directory (assuming debugfs is mounted at //sys/kernel/debug). -/debug/kprobes/list: Lists all registered probes on the system +/sys/kernel/debug/kprobes/list: Lists all registered probes on the system c015d71a k vfs_read+0x0 c011a316 j do_fork+0x0 @@ -525,7 +525,7 @@ virtual addresses that correspond to modules that've been unloaded), such probes are marked with [GONE]. If the probe is temporarily disabled, such probes are marked with [DISABLED]. -/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly. +/sys/kernel/debug/kprobes/enabled: Turn kprobes ON/OFF forcibly. Provides a knob to globally and forcibly turn registered kprobes ON or OFF. By default, all kprobes are enabled. By echoing "0" to this file, all diff --git a/Documentation/powerpc/dts-bindings/ecm.txt b/Documentation/powerpc/dts-bindings/ecm.txt new file mode 100644 index 000000000000..f514f29c67d6 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/ecm.txt @@ -0,0 +1,64 @@ +===================================================================== +E500 LAW & Coherency Module Device Tree Binding +Copyright (C) 2009 Freescale Semiconductor Inc. +===================================================================== + +Local Access Window (LAW) Node + +The LAW node represents the region of CCSR space where local access +windows are configured. For ECM based devices this is the first 4k +of CCSR space that includes CCSRBAR, ALTCBAR, ALTCAR, BPTR, and some +number of local access windows as specified by fsl,num-laws. + +PROPERTIES + + - compatible + Usage: required + Value type: <string> + Definition: Must include "fsl,ecm-law" + + - reg + Usage: required + Value type: <prop-encoded-array> + Definition: A standard property. The value specifies the + physical address offset and length of the CCSR space + registers. + + - fsl,num-laws + Usage: required + Value type: <u32> + Definition: The value specifies the number of local access + windows for this device. + +===================================================================== + +E500 Coherency Module Node + +The E500 LAW node represents the region of CCSR space where ECM config +and error reporting registers exist, this is the second 4k (0x1000) +of CCSR space. + +PROPERTIES + + - compatible + Usage: required + Value type: <string> + Definition: Must include "fsl,CHIP-ecm", "fsl,ecm" where + CHIP is the processor (mpc8572, mpc8544, etc.) + + - reg + Usage: required + Value type: <prop-encoded-array> + Definition: A standard property. The value specifies the + physical address offset and length of the CCSR space + registers. + + - interrupts + Usage: required + Value type: <prop-encoded-array> + + - interrupt-parent + Usage: required + Value type: <phandle> + +===================================================================== diff --git a/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe.txt b/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe.txt index 78790d58dc2c..6e37be1eeb2d 100644 --- a/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe.txt +++ b/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe.txt @@ -17,6 +17,9 @@ Required properties: - model : precise model of the QE, Can be "QE", "CPM", or "CPM2" - reg : offset and length of the device registers. - bus-frequency : the clock frequency for QUICC Engine. +- fsl,qe-num-riscs: define how many RISC engines the QE has. +- fsl,qe-num-snums: define how many serial number(SNUM) the QE can use for the + threads. Recommended properties - brg-frequency : the internal clock source frequency for baud-rate diff --git a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt index 600846557763..3ed3797b5086 100644 --- a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt +++ b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt @@ -5,17 +5,18 @@ for MMC, SD, and SDIO types of memory cards. Required properties: - compatible : should be - "fsl,<chip>-esdhc", "fsl,mpc8379-esdhc" for MPC83xx processors. - "fsl,<chip>-esdhc", "fsl,mpc8536-esdhc" for MPC85xx processors. + "fsl,<chip>-esdhc", "fsl,esdhc" - reg : should contain eSDHC registers location and length. - interrupts : should contain eSDHC interrupt. - interrupt-parent : interrupt source phandle. - clock-frequency : specifies eSDHC base clock frequency. + - sdhci,1-bit-only : (optional) specifies that a controller can + only handle 1-bit data transfers. Example: sdhci@2e000 { - compatible = "fsl,mpc8378-esdhc", "fsl,mpc8379-esdhc"; + compatible = "fsl,mpc8378-esdhc", "fsl,esdhc"; reg = <0x2e000 0x1000>; interrupts = <42 0x8>; interrupt-parent = <&ipic>; diff --git a/Documentation/powerpc/dts-bindings/fsl/mcm.txt b/Documentation/powerpc/dts-bindings/fsl/mcm.txt new file mode 100644 index 000000000000..4ceda9b3b413 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/fsl/mcm.txt @@ -0,0 +1,64 @@ +===================================================================== +MPX LAW & Coherency Module Device Tree Binding +Copyright (C) 2009 Freescale Semiconductor Inc. +===================================================================== + +Local Access Window (LAW) Node + +The LAW node represents the region of CCSR space where local access +windows are configured. For MCM based devices this is the first 4k +of CCSR space that includes CCSRBAR, ALTCBAR, ALTCAR, BPTR, and some +number of local access windows as specified by fsl,num-laws. + +PROPERTIES + + - compatible + Usage: required + Value type: <string> + Definition: Must include "fsl,mcm-law" + + - reg + Usage: required + Value type: <prop-encoded-array> + Definition: A standard property. The value specifies the + physical address offset and length of the CCSR space + registers. + + - fsl,num-laws + Usage: required + Value type: <u32> + Definition: The value specifies the number of local access + windows for this device. + +===================================================================== + +MPX Coherency Module Node + +The MPX LAW node represents the region of CCSR space where MCM config +and error reporting registers exist, this is the second 4k (0x1000) +of CCSR space. + +PROPERTIES + + - compatible + Usage: required + Value type: <string> + Definition: Must include "fsl,CHIP-mcm", "fsl,mcm" where + CHIP is the processor (mpc8641, mpc8610, etc.) + + - reg + Usage: required + Value type: <prop-encoded-array> + Definition: A standard property. The value specifies the + physical address offset and length of the CCSR space + registers. + + - interrupts + Usage: required + Value type: <prop-encoded-array> + + - interrupt-parent + Usage: required + Value type: <phandle> + +===================================================================== diff --git a/Documentation/pps/pps.txt b/Documentation/pps/pps.txt new file mode 100644 index 000000000000..125f4ab48998 --- /dev/null +++ b/Documentation/pps/pps.txt @@ -0,0 +1,172 @@ + + PPS - Pulse Per Second + ---------------------- + +(C) Copyright 2007 Rodolfo Giometti <giometti@enneenne.com> + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + + + +Overview +-------- + +LinuxPPS provides a programming interface (API) to define in the +system several PPS sources. + +PPS means "pulse per second" and a PPS source is just a device which +provides a high precision signal each second so that an application +can use it to adjust system clock time. + +A PPS source can be connected to a serial port (usually to the Data +Carrier Detect pin) or to a parallel port (ACK-pin) or to a special +CPU's GPIOs (this is the common case in embedded systems) but in each +case when a new pulse arrives the system must apply to it a timestamp +and record it for userland. + +Common use is the combination of the NTPD as userland program, with a +GPS receiver as PPS source, to obtain a wallclock-time with +sub-millisecond synchronisation to UTC. + + +RFC considerations +------------------ + +While implementing a PPS API as RFC 2783 defines and using an embedded +CPU GPIO-Pin as physical link to the signal, I encountered a deeper +problem: + + At startup it needs a file descriptor as argument for the function + time_pps_create(). + +This implies that the source has a /dev/... entry. This assumption is +ok for the serial and parallel port, where you can do something +useful besides(!) the gathering of timestamps as it is the central +task for a PPS-API. But this assumption does not work for a single +purpose GPIO line. In this case even basic file-related functionality +(like read() and write()) makes no sense at all and should not be a +precondition for the use of a PPS-API. + +The problem can be simply solved if you consider that a PPS source is +not always connected with a GPS data source. + +So your programs should check if the GPS data source (the serial port +for instance) is a PPS source too, and if not they should provide the +possibility to open another device as PPS source. + +In LinuxPPS the PPS sources are simply char devices usually mapped +into files /dev/pps0, /dev/pps1, etc.. + + +Coding example +-------------- + +To register a PPS source into the kernel you should define a struct +pps_source_info_s as follows: + + static struct pps_source_info pps_ktimer_info = { + .name = "ktimer", + .path = "", + .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | \ + PPS_ECHOASSERT | \ + PPS_CANWAIT | PPS_TSFMT_TSPEC, + .echo = pps_ktimer_echo, + .owner = THIS_MODULE, + }; + +and then calling the function pps_register_source() in your +intialization routine as follows: + + source = pps_register_source(&pps_ktimer_info, + PPS_CAPTUREASSERT | PPS_OFFSETASSERT); + +The pps_register_source() prototype is: + + int pps_register_source(struct pps_source_info_s *info, int default_params) + +where "info" is a pointer to a structure that describes a particular +PPS source, "default_params" tells the system what the initial default +parameters for the device should be (it is obvious that these parameters +must be a subset of ones defined in the struct +pps_source_info_s which describe the capabilities of the driver). + +Once you have registered a new PPS source into the system you can +signal an assert event (for example in the interrupt handler routine) +just using: + + pps_event(source, &ts, PPS_CAPTUREASSERT, ptr) + +where "ts" is the event's timestamp. + +The same function may also run the defined echo function +(pps_ktimer_echo(), passing to it the "ptr" pointer) if the user +asked for that... etc.. + +Please see the file drivers/pps/clients/ktimer.c for example code. + + +SYSFS support +------------- + +If the SYSFS filesystem is enabled in the kernel it provides a new class: + + $ ls /sys/class/pps/ + pps0/ pps1/ pps2/ + +Every directory is the ID of a PPS sources defined in the system and +inside you find several files: + + $ ls /sys/class/pps/pps0/ + assert clear echo mode name path subsystem@ uevent + +Inside each "assert" and "clear" file you can find the timestamp and a +sequence number: + + $ cat /sys/class/pps/pps0/assert + 1170026870.983207967#8 + +Where before the "#" is the timestamp in seconds; after it is the +sequence number. Other files are: + +* echo: reports if the PPS source has an echo function or not; + +* mode: reports available PPS functioning modes; + +* name: reports the PPS source's name; + +* path: reports the PPS source's device path, that is the device the + PPS source is connected to (if it exists). + + +Testing the PPS support +----------------------- + +In order to test the PPS support even without specific hardware you can use +the ktimer driver (see the client subsection in the PPS configuration menu) +and the userland tools provided into Documentaion/pps/ directory. + +Once you have enabled the compilation of ktimer just modprobe it (if +not statically compiled): + + # modprobe ktimer + +and the run ppstest as follow: + + $ ./ppstest /dev/pps0 + trying PPS source "/dev/pps1" + found PPS source "/dev/pps1" + ok, found 1 source(s), now start fetching data... + source 0 - assert 1186592699.388832443, sequence: 364 - clear 0.000000000, sequence: 0 + source 0 - assert 1186592700.388931295, sequence: 365 - clear 0.000000000, sequence: 0 + source 0 - assert 1186592701.389032765, sequence: 366 - clear 0.000000000, sequence: 0 + +Please, note that to compile userland programs you need the file timepps.h +(see Documentation/pps/). diff --git a/Documentation/robust-futex-ABI.txt b/Documentation/robust-futex-ABI.txt index 535f69fab45f..fd1cd8aae4eb 100644 --- a/Documentation/robust-futex-ABI.txt +++ b/Documentation/robust-futex-ABI.txt @@ -135,7 +135,7 @@ manipulating this list), the user code must observe the following protocol on 'lock entry' insertion and removal: On insertion: - 1) set the 'list_op_pending' word to the address of the 'lock word' + 1) set the 'list_op_pending' word to the address of the 'lock entry' to be inserted, 2) acquire the futex lock, 3) add the lock entry, with its thread id (TID) in the bottom 29 bits @@ -143,7 +143,7 @@ On insertion: 4) clear the 'list_op_pending' word. On removal: - 1) set the 'list_op_pending' word to the address of the 'lock word' + 1) set the 'list_op_pending' word to the address of the 'lock entry' to be removed, 2) remove the lock entry for this lock from the 'head' list, 2) release the futex lock, and diff --git a/Documentation/scsi/scsi_fc_transport.txt b/Documentation/scsi/scsi_fc_transport.txt index e5b071d46619..d7f181701dc2 100644 --- a/Documentation/scsi/scsi_fc_transport.txt +++ b/Documentation/scsi/scsi_fc_transport.txt @@ -1,10 +1,11 @@ SCSI FC Tansport ============================================= -Date: 4/12/2007 +Date: 11/18/2008 Kernel Revisions for features: rports : <<TBS>> - vports : 2.6.22 (? TBD) + vports : 2.6.22 + bsg support : 2.6.30 (?TBD?) Introduction @@ -15,6 +16,7 @@ The FC transport can be found at: drivers/scsi/scsi_transport_fc.c include/scsi/scsi_transport_fc.h include/scsi/scsi_netlink_fc.h + include/scsi/scsi_bsg_fc.h This file is found at Documentation/scsi/scsi_fc_transport.txt @@ -472,6 +474,14 @@ int fc_vport_terminate(struct fc_vport *vport) +FC BSG support (CT & ELS passthru, and more) +======================================================================== +<< To Be Supplied >> + + + + + Credits ======= The following people have contributed to this document: diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt index a6d5354639b2..de67229251d8 100644 --- a/Documentation/scsi/scsi_mid_low_api.txt +++ b/Documentation/scsi/scsi_mid_low_api.txt @@ -1271,6 +1271,11 @@ of interest: hostdata[0] - area reserved for LLD at end of struct Scsi_Host. Size is set by the second argument (named 'xtr_bytes') to scsi_host_alloc() or scsi_register(). + vendor_id - a unique value that identifies the vendor supplying + the LLD for the Scsi_Host. Used most often in validating + vendor-specific message requests. Value consists of an + identifier type and a vendor-specific value. + See scsi_netlink.h for a description of valid formats. The scsi_host structure is defined in include/scsi/scsi_host.h diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index de8e10a94103..0d8d23581c44 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -139,6 +139,7 @@ ALC883/888 acer Acer laptops (Travelmate 3012WTMi, Aspire 5600, etc) acer-aspire Acer Aspire 9810 acer-aspire-4930g Acer Aspire 4930G + acer-aspire-6530g Acer Aspire 6530G acer-aspire-8930g Acer Aspire 8930G medion Medion Laptops medion-md2 Medion MD2 diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 6fab2dcbb4d3..c4de6359d440 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -233,8 +233,8 @@ These protections are added to score to judge whether this zone should be used for page allocation or should be reclaimed. In this example, if normal pages (index=2) are required to this DMA zone and -pages_high is used for watermark, the kernel judges this zone should not be -used because pages_free(1355) is smaller than watermark + protection[2] +watermark[WMARK_HIGH] is used for watermark, the kernel judges this zone should +not be used because pages_free(1355) is smaller than watermark + protection[2] (4 + 2004 = 2008). If this protection value is 0, this zone would be used for normal page requirement. If requirement is DMA zone(index=0), protection[0] (=0) is used. @@ -280,9 +280,10 @@ The default value is 65536. min_free_kbytes: This is used to force the Linux VM to keep a minimum number -of kilobytes free. The VM uses this number to compute a pages_min -value for each lowmem zone in the system. Each lowmem zone gets -a number of reserved free pages based proportionally on its size. +of kilobytes free. The VM uses this number to compute a +watermark[WMARK_MIN] value for each lowmem zone in the system. +Each lowmem zone gets a number of reserved free pages based +proportionally on its size. Some minimal amount of memory is needed to satisfy PF_MEMALLOC allocations; if you set this to lower than 1024KB, your system will @@ -314,10 +315,14 @@ min_unmapped_ratio: This is available only on NUMA kernels. -A percentage of the total pages in each zone. Zone reclaim will only -occur if more than this percentage of pages are file backed and unmapped. -This is to insure that a minimal amount of local pages is still available for -file I/O even if the node is overallocated. +This is a percentage of the total pages in each zone. Zone reclaim will +only occur if more than this percentage of pages are in a state that +zone_reclaim_mode allows to be reclaimed. + +If zone_reclaim_mode has the value 4 OR'd, then the percentage is compared +against all file-backed unmapped pages including swapcache pages and tmpfs +files. Otherwise, only unmapped pages backed by normal files but not tmpfs +files and similar are considered. The default is 1 percent. diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt index 7bd27f0e2880..a39b3c749de5 100644 --- a/Documentation/trace/ftrace.txt +++ b/Documentation/trace/ftrace.txt @@ -7,7 +7,6 @@ Copyright 2008 Red Hat Inc. (dual licensed under the GPL v2) Reviewers: Elias Oltmanns, Randy Dunlap, Andrew Morton, John Kacur, and David Teigland. - Written for: 2.6.28-rc2 Introduction @@ -33,13 +32,26 @@ The File System Ftrace uses the debugfs file system to hold the control files as well as the files to display output. -To mount the debugfs system: +When debugfs is configured into the kernel (which selecting any ftrace +option will do) the directory /sys/kernel/debug will be created. To mount +this directory, you can add to your /etc/fstab file: + + debugfs /sys/kernel/debug debugfs defaults 0 0 + +Or you can mount it at run time with: + + mount -t debugfs nodev /sys/kernel/debug - # mkdir /debug - # mount -t debugfs nodev /debug +For quicker access to that directory you may want to make a soft link to +it: -( Note: it is more common to mount at /sys/kernel/debug, but for - simplicity this document will use /debug) + ln -s /sys/kernel/debug /debug + +Any selected ftrace option will also create a directory called tracing +within the debugfs. The rest of the document will assume that you are in +the ftrace directory (cd /sys/kernel/debug/tracing) and will only concentrate +on the files within that directory and not distract from the content with +the extended "/sys/kernel/debug/tracing" path name. That's it! (assuming that you have ftrace configured into your kernel) @@ -389,18 +401,18 @@ trace_options The trace_options file is used to control what gets printed in the trace output. To see what is available, simply cat the file: - cat /debug/tracing/trace_options + cat trace_options print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \ noblock nostacktrace nosched-tree nouserstacktrace nosym-userobj To disable one of the options, echo in the option prepended with "no". - echo noprint-parent > /debug/tracing/trace_options + echo noprint-parent > trace_options To enable an option, leave off the "no". - echo sym-offset > /debug/tracing/trace_options + echo sym-offset > trace_options Here are the available options: @@ -476,11 +488,11 @@ sched_switch This tracer simply records schedule switches. Here is an example of how to use it. - # echo sched_switch > /debug/tracing/current_tracer - # echo 1 > /debug/tracing/tracing_enabled + # echo sched_switch > current_tracer + # echo 1 > tracing_enabled # sleep 1 - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/trace + # echo 0 > tracing_enabled + # cat trace # tracer: sched_switch # @@ -583,13 +595,13 @@ new trace is saved. To reset the maximum, echo 0 into tracing_max_latency. Here is an example: - # echo irqsoff > /debug/tracing/current_tracer - # echo 0 > /debug/tracing/tracing_max_latency - # echo 1 > /debug/tracing/tracing_enabled + # echo irqsoff > current_tracer + # echo 0 > tracing_max_latency + # echo 1 > tracing_enabled # ls -ltr [...] - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/latency_trace + # echo 0 > tracing_enabled + # cat latency_trace # tracer: irqsoff # irqsoff latency trace v1.1.5 on 2.6.26 @@ -690,13 +702,13 @@ Like the irqsoff tracer, it records the maximum latency for which preemption was disabled. The control of preemptoff tracer is much like the irqsoff tracer. - # echo preemptoff > /debug/tracing/current_tracer - # echo 0 > /debug/tracing/tracing_max_latency - # echo 1 > /debug/tracing/tracing_enabled + # echo preemptoff > current_tracer + # echo 0 > tracing_max_latency + # echo 1 > tracing_enabled # ls -ltr [...] - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/latency_trace + # echo 0 > tracing_enabled + # cat latency_trace # tracer: preemptoff # preemptoff latency trace v1.1.5 on 2.6.26-rc8 @@ -837,13 +849,13 @@ tracer. Again, using this trace is much like the irqsoff and preemptoff tracers. - # echo preemptirqsoff > /debug/tracing/current_tracer - # echo 0 > /debug/tracing/tracing_max_latency - # echo 1 > /debug/tracing/tracing_enabled + # echo preemptirqsoff > current_tracer + # echo 0 > tracing_max_latency + # echo 1 > tracing_enabled # ls -ltr [...] - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/latency_trace + # echo 0 > tracing_enabled + # cat latency_trace # tracer: preemptirqsoff # preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8 @@ -999,12 +1011,12 @@ slightly differently than we did with the previous tracers. Instead of performing an 'ls', we will run 'sleep 1' under 'chrt' which changes the priority of the task. - # echo wakeup > /debug/tracing/current_tracer - # echo 0 > /debug/tracing/tracing_max_latency - # echo 1 > /debug/tracing/tracing_enabled + # echo wakeup > current_tracer + # echo 0 > tracing_max_latency + # echo 1 > tracing_enabled # chrt -f 5 sleep 1 - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/latency_trace + # echo 0 > tracing_enabled + # cat latency_trace # tracer: wakeup # wakeup latency trace v1.1.5 on 2.6.26-rc8 @@ -1114,11 +1126,11 @@ can be done from the debug file system. Make sure the ftrace_enabled is set; otherwise this tracer is a nop. # sysctl kernel.ftrace_enabled=1 - # echo function > /debug/tracing/current_tracer - # echo 1 > /debug/tracing/tracing_enabled + # echo function > current_tracer + # echo 1 > tracing_enabled # usleep 1 - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/trace + # echo 0 > tracing_enabled + # cat trace # tracer: function # # TASK-PID CPU# TIMESTAMP FUNCTION @@ -1155,7 +1167,7 @@ int trace_fd; [...] int main(int argc, char *argv[]) { [...] - trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY); + trace_fd = open(tracing_file("tracing_enabled"), O_WRONLY); [...] if (condition_hit()) { write(trace_fd, "0", 1); @@ -1163,26 +1175,20 @@ int main(int argc, char *argv[]) { [...] } -Note: Here we hard coded the path name. The debugfs mount is not -guaranteed to be at /debug (and is more commonly at -/sys/kernel/debug). For simple one time traces, the above is -sufficent. For anything else, a search through /proc/mounts may -be needed to find where the debugfs file-system is mounted. - Single thread tracing --------------------- -By writing into /debug/tracing/set_ftrace_pid you can trace a +By writing into set_ftrace_pid you can trace a single thread. For example: -# cat /debug/tracing/set_ftrace_pid +# cat set_ftrace_pid no pid -# echo 3111 > /debug/tracing/set_ftrace_pid -# cat /debug/tracing/set_ftrace_pid +# echo 3111 > set_ftrace_pid +# cat set_ftrace_pid 3111 -# echo function > /debug/tracing/current_tracer -# cat /debug/tracing/trace | head +# echo function > current_tracer +# cat trace | head # tracer: function # # TASK-PID CPU# TIMESTAMP FUNCTION @@ -1193,8 +1199,8 @@ no pid yum-updatesd-3111 [003] 1637.254683: lock_hrtimer_base <-hrtimer_try_to_cancel yum-updatesd-3111 [003] 1637.254685: fget_light <-do_sys_poll yum-updatesd-3111 [003] 1637.254686: pipe_poll <-do_sys_poll -# echo -1 > /debug/tracing/set_ftrace_pid -# cat /debug/tracing/trace |head +# echo -1 > set_ftrace_pid +# cat trace |head # tracer: function # # TASK-PID CPU# TIMESTAMP FUNCTION @@ -1216,6 +1222,51 @@ something like this simple program: #include <fcntl.h> #include <unistd.h> +#define _STR(x) #x +#define STR(x) _STR(x) +#define MAX_PATH 256 + +const char *find_debugfs(void) +{ + static char debugfs[MAX_PATH+1]; + static int debugfs_found; + char type[100]; + FILE *fp; + + if (debugfs_found) + return debugfs; + + if ((fp = fopen("/proc/mounts","r")) == NULL) { + perror("/proc/mounts"); + return NULL; + } + + while (fscanf(fp, "%*s %" + STR(MAX_PATH) + "s %99s %*s %*d %*d\n", + debugfs, type) == 2) { + if (strcmp(type, "debugfs") == 0) + break; + } + fclose(fp); + + if (strcmp(type, "debugfs") != 0) { + fprintf(stderr, "debugfs not mounted"); + return NULL; + } + + debugfs_found = 1; + + return debugfs; +} + +const char *tracing_file(const char *file_name) +{ + static char trace_file[MAX_PATH+1]; + snprintf(trace_file, MAX_PATH, "%s/%s", find_debugfs(), file_name); + return trace_file; +} + int main (int argc, char **argv) { if (argc < 1) @@ -1226,12 +1277,12 @@ int main (int argc, char **argv) char line[64]; int s; - ffd = open("/debug/tracing/current_tracer", O_WRONLY); + ffd = open(tracing_file("current_tracer"), O_WRONLY); if (ffd < 0) exit(-1); write(ffd, "nop", 3); - fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY); + fd = open(tracing_file("set_ftrace_pid"), O_WRONLY); s = sprintf(line, "%d\n", getpid()); write(fd, line, s); @@ -1383,22 +1434,22 @@ want, depending on your needs. tracing_cpu_mask file) or you might sometimes see unordered function calls while cpu tracing switch. - hide: echo nofuncgraph-cpu > /debug/tracing/trace_options - show: echo funcgraph-cpu > /debug/tracing/trace_options + hide: echo nofuncgraph-cpu > trace_options + show: echo funcgraph-cpu > trace_options - The duration (function's time of execution) is displayed on the closing bracket line of a function or on the same line than the current function in case of a leaf one. It is default enabled. - hide: echo nofuncgraph-duration > /debug/tracing/trace_options - show: echo funcgraph-duration > /debug/tracing/trace_options + hide: echo nofuncgraph-duration > trace_options + show: echo funcgraph-duration > trace_options - The overhead field precedes the duration field in case of reached duration thresholds. - hide: echo nofuncgraph-overhead > /debug/tracing/trace_options - show: echo funcgraph-overhead > /debug/tracing/trace_options + hide: echo nofuncgraph-overhead > trace_options + show: echo funcgraph-overhead > trace_options depends on: funcgraph-duration ie: @@ -1427,8 +1478,8 @@ want, depending on your needs. - The task/pid field displays the thread cmdline and pid which executed the function. It is default disabled. - hide: echo nofuncgraph-proc > /debug/tracing/trace_options - show: echo funcgraph-proc > /debug/tracing/trace_options + hide: echo nofuncgraph-proc > trace_options + show: echo funcgraph-proc > trace_options ie: @@ -1451,8 +1502,8 @@ want, depending on your needs. system clock since it started. A snapshot of this time is given on each entry/exit of functions - hide: echo nofuncgraph-abstime > /debug/tracing/trace_options - show: echo funcgraph-abstime > /debug/tracing/trace_options + hide: echo nofuncgraph-abstime > trace_options + show: echo funcgraph-abstime > trace_options ie: @@ -1549,7 +1600,7 @@ listed in: available_filter_functions - # cat /debug/tracing/available_filter_functions + # cat available_filter_functions put_prev_task_idle kmem_cache_create pick_next_task_rt @@ -1561,12 +1612,12 @@ mutex_lock If I am only interested in sys_nanosleep and hrtimer_interrupt: # echo sys_nanosleep hrtimer_interrupt \ - > /debug/tracing/set_ftrace_filter - # echo ftrace > /debug/tracing/current_tracer - # echo 1 > /debug/tracing/tracing_enabled + > set_ftrace_filter + # echo ftrace > current_tracer + # echo 1 > tracing_enabled # usleep 1 - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/trace + # echo 0 > tracing_enabled + # cat trace # tracer: ftrace # # TASK-PID CPU# TIMESTAMP FUNCTION @@ -1577,7 +1628,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt: To see which functions are being traced, you can cat the file: - # cat /debug/tracing/set_ftrace_filter + # cat set_ftrace_filter hrtimer_interrupt sys_nanosleep @@ -1597,7 +1648,7 @@ Note: It is better to use quotes to enclose the wild cards, otherwise the shell may expand the parameters into names of files in the local directory. - # echo 'hrtimer_*' > /debug/tracing/set_ftrace_filter + # echo 'hrtimer_*' > set_ftrace_filter Produces: @@ -1618,7 +1669,7 @@ Produces: Notice that we lost the sys_nanosleep. - # cat /debug/tracing/set_ftrace_filter + # cat set_ftrace_filter hrtimer_run_queues hrtimer_run_pending hrtimer_init @@ -1644,17 +1695,17 @@ To append to the filters, use '>>' To clear out a filter so that all functions will be recorded again: - # echo > /debug/tracing/set_ftrace_filter - # cat /debug/tracing/set_ftrace_filter + # echo > set_ftrace_filter + # cat set_ftrace_filter # Again, now we want to append. - # echo sys_nanosleep > /debug/tracing/set_ftrace_filter - # cat /debug/tracing/set_ftrace_filter + # echo sys_nanosleep > set_ftrace_filter + # cat set_ftrace_filter sys_nanosleep - # echo 'hrtimer_*' >> /debug/tracing/set_ftrace_filter - # cat /debug/tracing/set_ftrace_filter + # echo 'hrtimer_*' >> set_ftrace_filter + # cat set_ftrace_filter hrtimer_run_queues hrtimer_run_pending hrtimer_init @@ -1677,7 +1728,7 @@ hrtimer_init_sleeper The set_ftrace_notrace prevents those functions from being traced. - # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace + # echo '*preempt*' '*lock*' > set_ftrace_notrace Produces: @@ -1767,13 +1818,13 @@ the effect on the tracing is different. Every read from trace_pipe is consumed. This means that subsequent reads will be different. The trace is live. - # echo function > /debug/tracing/current_tracer - # cat /debug/tracing/trace_pipe > /tmp/trace.out & + # echo function > current_tracer + # cat trace_pipe > /tmp/trace.out & [1] 4153 - # echo 1 > /debug/tracing/tracing_enabled + # echo 1 > tracing_enabled # usleep 1 - # echo 0 > /debug/tracing/tracing_enabled - # cat /debug/tracing/trace + # echo 0 > tracing_enabled + # cat trace # tracer: function # # TASK-PID CPU# TIMESTAMP FUNCTION @@ -1809,7 +1860,7 @@ number listed is the number of entries that can be recorded per CPU. To know the full size, multiply the number of possible CPUS with the number of entries. - # cat /debug/tracing/buffer_size_kb + # cat buffer_size_kb 1408 (units kilobytes) Note, to modify this, you must have tracing completely disabled. @@ -1817,18 +1868,18 @@ To do that, echo "nop" into the current_tracer. If the current_tracer is not set to "nop", an EINVAL error will be returned. - # echo nop > /debug/tracing/current_tracer - # echo 10000 > /debug/tracing/buffer_size_kb - # cat /debug/tracing/buffer_size_kb + # echo nop > current_tracer + # echo 10000 > buffer_size_kb + # cat buffer_size_kb 10000 (units kilobytes) The number of pages which will be allocated is limited to a percentage of available memory. Allocating too much will produce an error. - # echo 1000000000000 > /debug/tracing/buffer_size_kb + # echo 1000000000000 > buffer_size_kb -bash: echo: write error: Cannot allocate memory - # cat /debug/tracing/buffer_size_kb + # cat buffer_size_kb 85 ----------- diff --git a/Documentation/trace/mmiotrace.txt b/Documentation/trace/mmiotrace.txt index 5731c67abc55..162effbfbdec 100644 --- a/Documentation/trace/mmiotrace.txt +++ b/Documentation/trace/mmiotrace.txt @@ -32,41 +32,41 @@ is no way to automatically detect if you are losing events due to CPUs racing. Usage Quick Reference --------------------- -$ mount -t debugfs debugfs /debug -$ echo mmiotrace > /debug/tracing/current_tracer -$ cat /debug/tracing/trace_pipe > mydump.txt & +$ mount -t debugfs debugfs /sys/kernel/debug +$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer +$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt & Start X or whatever. -$ echo "X is up" > /debug/tracing/trace_marker -$ echo nop > /debug/tracing/current_tracer +$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker +$ echo nop > /sys/kernel/debug/tracing/current_tracer Check for lost events. Usage ----- -Make sure debugfs is mounted to /debug. If not, (requires root privileges) -$ mount -t debugfs debugfs /debug +Make sure debugfs is mounted to /sys/kernel/debug. If not, (requires root privileges) +$ mount -t debugfs debugfs /sys/kernel/debug Check that the driver you are about to trace is not loaded. Activate mmiotrace (requires root privileges): -$ echo mmiotrace > /debug/tracing/current_tracer +$ echo mmiotrace > /sys/kernel/debug/tracing/current_tracer Start storing the trace: -$ cat /debug/tracing/trace_pipe > mydump.txt & +$ cat /sys/kernel/debug/tracing/trace_pipe > mydump.txt & The 'cat' process should stay running (sleeping) in the background. Load the driver you want to trace and use it. Mmiotrace will only catch MMIO accesses to areas that are ioremapped while mmiotrace is active. During tracing you can place comments (markers) into the trace by -$ echo "X is up" > /debug/tracing/trace_marker +$ echo "X is up" > /sys/kernel/debug/tracing/trace_marker This makes it easier to see which part of the (huge) trace corresponds to which action. It is recommended to place descriptive markers about what you do. Shut down mmiotrace (requires root privileges): -$ echo nop > /debug/tracing/current_tracer +$ echo nop > /sys/kernel/debug/tracing/current_tracer The 'cat' process exits. If it does not, kill it by issuing 'fg' command and pressing ctrl+c. @@ -78,10 +78,10 @@ to view your kernel log and look for "mmiotrace has lost events" warning. If events were lost, the trace is incomplete. You should enlarge the buffers and try again. Buffers are enlarged by first seeing how large the current buffers are: -$ cat /debug/tracing/buffer_size_kb +$ cat /sys/kernel/debug/tracing/buffer_size_kb gives you a number. Approximately double this number and write it back, for instance: -$ echo 128000 > /debug/tracing/buffer_size_kb +$ echo 128000 > /sys/kernel/debug/tracing/buffer_size_kb Then start again from the top. If you are doing a trace for a driver project, e.g. Nouveau, you should also diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 91aa3c0f0dd2..450b8f8c389b 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 @@ -16,3 +16,8 @@ 15 -> TeVii S470 [d470:9022] 16 -> DVBWorld DVB-S2 2005 [0001:2005] 17 -> NetUP Dual DVB-S2 CI [1b55:2a2c] + 18 -> Hauppauge WinTV-HVR1270 [0070:2211] + 19 -> Hauppauge WinTV-HVR1275 [0070:2215] + 20 -> Hauppauge WinTV-HVR1255 [0070:2251] + 21 -> Hauppauge WinTV-HVR1210 [0070:2291,0070:2295] + 22 -> Mygica X8506 DMB-TH [14f1:8651] diff --git a/Documentation/video4linux/CARDLIST.cx88 b/Documentation/video4linux/CARDLIST.cx88 index 71e9db0b26f7..89093f531727 100644 --- a/Documentation/video4linux/CARDLIST.cx88 +++ b/Documentation/video4linux/CARDLIST.cx88 @@ -78,3 +78,5 @@ 77 -> TBS 8910 DVB-S [8910:8888] 78 -> Prof 6200 DVB-S [b022:3022] 79 -> Terratec Cinergy HT PCI MKII [153b:1177] + 80 -> Hauppauge WinTV-IR Only [0070:9290] + 81 -> Leadtek WinFast DTV1800 Hybrid [107d:6654] diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index 78d0a6eed571..a98a688c11b8 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -17,7 +17,7 @@ 16 -> Hauppauge WinTV HVR 950 (em2883) [2040:6513,2040:6517,2040:651b] 17 -> Pinnacle PCTV HD Pro Stick (em2880) [2304:0227] 18 -> Hauppauge WinTV HVR 900 (R2) (em2880) [2040:6502] - 19 -> PointNix Intra-Oral Camera (em2860) + 19 -> EM2860/SAA711X Reference Design (em2860) 20 -> AMD ATI TV Wonder HD 600 (em2880) [0438:b002] 21 -> eMPIA Technology, Inc. GrabBeeX+ Video Encoder (em2800) [eb1a:2801] 22 -> Unknown EM2750/EM2751 webcam grabber (em2750) [eb1a:2750,eb1a:2751] @@ -61,3 +61,7 @@ 63 -> Kaiomy TVnPC U2 (em2860) [eb1a:e303] 64 -> Easy Cap Capture DC-60 (em2860) 65 -> IO-DATA GV-MVP/SZ (em2820/em2840) [04bb:0515] + 66 -> Empire dual TV (em2880) + 67 -> Terratec Grabby (em2860) [0ccd:0096] + 68 -> Terratec AV350 (em2860) [0ccd:0084] + 69 -> KWorld ATSC 315U HDTV TV Box (em2882) [eb1a:a313] diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index 6dacf2825259..15562427e8a9 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 @@ -124,10 +124,10 @@ 123 -> Beholder BeholdTV 407 [0000:4070] 124 -> Beholder BeholdTV 407 FM [0000:4071] 125 -> Beholder BeholdTV 409 [0000:4090] -126 -> Beholder BeholdTV 505 FM/RDS [0000:5051,0000:505B,5ace:5050] -127 -> Beholder BeholdTV 507 FM/RDS / BeholdTV 509 FM [0000:5071,0000:507B,5ace:5070,5ace:5090] +126 -> Beholder BeholdTV 505 FM [5ace:5050] +127 -> Beholder BeholdTV 507 FM / BeholdTV 509 FM [5ace:5070,5ace:5090] 128 -> Beholder BeholdTV Columbus TVFM [0000:5201] -129 -> Beholder BeholdTV 607 / BeholdTV 609 [5ace:6070,5ace:6071,5ace:6072,5ace:6073,5ace:6090,5ace:6091,5ace:6092,5ace:6093] +129 -> Beholder BeholdTV 607 FM [5ace:6070] 130 -> Beholder BeholdTV M6 [5ace:6190] 131 -> Twinhan Hybrid DTV-DVB 3056 PCI [1822:0022] 132 -> Genius TVGO AM11MCE @@ -143,7 +143,7 @@ 142 -> Beholder BeholdTV H6 [5ace:6290] 143 -> Beholder BeholdTV M63 [5ace:6191] 144 -> Beholder BeholdTV M6 Extra [5ace:6193] -145 -> AVerMedia MiniPCI DVB-T Hybrid M103 [1461:f636] +145 -> AVerMedia MiniPCI DVB-T Hybrid M103 [1461:f636,1461:f736] 146 -> ASUSTeK P7131 Analog 147 -> Asus Tiger 3in1 [1043:4878] 148 -> Encore ENLTV-FM v5.3 [1a7f:2008] @@ -154,4 +154,16 @@ 153 -> Kworld Plus TV Analog Lite PCI [17de:7128] 154 -> Avermedia AVerTV GO 007 FM Plus [1461:f31d] 155 -> Hauppauge WinTV-HVR1120 ATSC/QAM-Hybrid [0070:6706,0070:6708] -156 -> Hauppauge WinTV-HVR1110r3 [0070:6707,0070:6709,0070:670a] +156 -> Hauppauge WinTV-HVR1110r3 DVB-T/Hybrid [0070:6707,0070:6709,0070:670a] +157 -> Avermedia AVerTV Studio 507UA [1461:a11b] +158 -> AVerMedia Cardbus TV/Radio (E501R) [1461:b7e9] +159 -> Beholder BeholdTV 505 RDS [0000:505B] +160 -> Beholder BeholdTV 507 RDS [0000:5071] +161 -> Beholder BeholdTV 507 RDS [0000:507B] +162 -> Beholder BeholdTV 607 FM [5ace:6071] +163 -> Beholder BeholdTV 609 FM [5ace:6090] +164 -> Beholder BeholdTV 609 FM [5ace:6091] +165 -> Beholder BeholdTV 607 RDS [5ace:6072] +166 -> Beholder BeholdTV 607 RDS [5ace:6073] +167 -> Beholder BeholdTV 609 RDS [5ace:6092] +168 -> Beholder BeholdTV 609 RDS [5ace:6093] diff --git a/Documentation/video4linux/CARDLIST.tuner b/Documentation/video4linux/CARDLIST.tuner index 691d2f37dc57..be67844074dd 100644 --- a/Documentation/video4linux/CARDLIST.tuner +++ b/Documentation/video4linux/CARDLIST.tuner @@ -76,3 +76,5 @@ tuner=75 - Philips TEA5761 FM Radio tuner=76 - Xceive 5000 tuner tuner=77 - TCL tuner MF02GIP-5N-E tuner=78 - Philips FMD1216MEX MK3 Hybrid Tuner +tuner=79 - Philips PAL/SECAM multi (FM1216 MK5) +tuner=80 - Philips FQ1216LME MK3 PAL/SECAM w/active loopthrough diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index 98529e03a46e..2bcf78896e22 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt @@ -163,10 +163,11 @@ sunplus 055f:c650 Mustek MDC5500Z zc3xx 055f:d003 Mustek WCam300A zc3xx 055f:d004 Mustek WCam300 AN conex 0572:0041 Creative Notebook cx11646 -ov519 05a9:0519 OmniVision +ov519 05a9:0519 OV519 Microphone ov519 05a9:0530 OmniVision -ov519 05a9:4519 OmniVision +ov519 05a9:4519 Webcam Classic ov519 05a9:8519 OmniVision +ov519 05a9:a518 D-Link DSB-C310 Webcam sunplus 05da:1018 Digital Dream Enigma 1.3 stk014 05e1:0893 Syntek DV4000 spca561 060b:a001 Maxell Compact Pc PM3 @@ -178,6 +179,7 @@ spca506 06e1:a190 ADS Instant VCD ov534 06f8:3002 Hercules Blog Webcam ov534 06f8:3003 Hercules Dualpix HD Weblog sonixj 06f8:3004 Hercules Classic Silver +sonixj 06f8:3008 Hercules Deluxe Optical Glass spca508 0733:0110 ViewQuest VQ110 spca508 0130:0130 Clone Digital Webcam 11043 spca501 0733:0401 Intel Create and Share @@ -209,6 +211,7 @@ sunplus 08ca:2050 Medion MD 41437 sunplus 08ca:2060 Aiptek PocketDV5300 tv8532 0923:010f ICM532 cams mars 093a:050f Mars-Semi Pc-Camera +mr97310a 093a:010f Sakar Digital no. 77379 pac207 093a:2460 Qtec Webcam 100 pac207 093a:2461 HP Webcam pac207 093a:2463 Philips SPC 220 NC @@ -265,6 +268,11 @@ sonixj 0c45:60ec SN9C105+MO4000 sonixj 0c45:60fb Surfer NoName sonixj 0c45:60fc LG-LIC300 sonixj 0c45:60fe Microdia Audio +sonixj 0c45:6100 PC Camera (SN9C128) +sonixj 0c45:610a PC Camera (SN9C128) +sonixj 0c45:610b PC Camera (SN9C128) +sonixj 0c45:610c PC Camera (SN9C128) +sonixj 0c45:610e PC Camera (SN9C128) sonixj 0c45:6128 Microdia/Sonix SNP325 sonixj 0c45:612a Avant Camera sonixj 0c45:612c Typhoon Rasy Cam 1.3MPix diff --git a/Documentation/video4linux/pxa_camera.txt b/Documentation/video4linux/pxa_camera.txt index b1137f9a53eb..4f6d0ca01956 100644 --- a/Documentation/video4linux/pxa_camera.txt +++ b/Documentation/video4linux/pxa_camera.txt @@ -26,6 +26,55 @@ Global video workflow Once the last buffer is filled in, the QCI interface stops. + c) Capture global finite state machine schema + + +----+ +---+ +----+ + | DQ | | Q | | DQ | + | v | v | v + +-----------+ +------------------------+ + | STOP | | Wait for capture start | + +-----------+ Q +------------------------+ ++-> | QCI: stop | ------------------> | QCI: run | <------------+ +| | DMA: stop | | DMA: stop | | +| +-----------+ +-----> +------------------------+ | +| / | | +| / +---+ +----+ | | +|capture list empty / | Q | | DQ | | QCI Irq EOF | +| / | v | v v | +| +--------------------+ +----------------------+ | +| | DMA hotlink missed | | Capture running | | +| +--------------------+ +----------------------+ | +| | QCI: run | +-----> | QCI: run | <-+ | +| | DMA: stop | / | DMA: run | | | +| +--------------------+ / +----------------------+ | Other | +| ^ /DMA still | | channels | +| | capture list / running | DMA Irq End | not | +| | not empty / | | finished | +| | / v | yet | +| +----------------------+ +----------------------+ | | +| | Videobuf released | | Channel completed | | | +| +----------------------+ +----------------------+ | | ++-- | QCI: run | | QCI: run | --+ | + | DMA: run | | DMA: run | | + +----------------------+ +----------------------+ | + ^ / | | + | no overrun / | overrun | + | / v | + +--------------------+ / +----------------------+ | + | Frame completed | / | Frame overran | | + +--------------------+ <-----+ +----------------------+ restart frame | + | QCI: run | | QCI: stop | --------------+ + | DMA: run | | DMA: stop | + +--------------------+ +----------------------+ + + Legend: - each box is a FSM state + - each arrow is the condition to transition to another state + - an arrow with a comment is a mandatory transition (no condition) + - arrow "Q" means : a buffer was enqueued + - arrow "DQ" means : a buffer was dequeued + - "QCI: stop" means the QCI interface is not enabled + - "DMA: stop" means all 3 DMA channels are stopped + - "DMA: run" means at least 1 DMA channel is still running DMA usage --------- diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 854808b67fae..d54c1e4c6a9c 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -89,6 +89,11 @@ from dev (driver name followed by the bus_id, to be precise). If you set it up before calling v4l2_device_register then it will be untouched. If dev is NULL, then you *must* setup v4l2_dev->name before calling v4l2_device_register. +You can use v4l2_device_set_name() to set the name based on a driver name and +a driver-global atomic_t instance. This will generate names like ivtv0, ivtv1, +etc. If the name ends with a digit, then it will insert a dash: cx18-0, +cx18-1, etc. This function returns the instance number. + The first 'dev' argument is normally the struct device pointer of a pci_dev, usb_interface or platform_device. It is rare for dev to be NULL, but it happens with ISA devices or when one device creates multiple PCI devices, thus making diff --git a/Documentation/vm/Makefile b/Documentation/vm/Makefile index 6f562f778b28..5bd269b3731a 100644 --- a/Documentation/vm/Makefile +++ b/Documentation/vm/Makefile @@ -2,7 +2,7 @@ obj- := dummy.o # List of programs to build -hostprogs-y := slabinfo +hostprogs-y := slabinfo page-types # Tell kbuild to always build the programs always := $(hostprogs-y) diff --git a/Documentation/vm/balance b/Documentation/vm/balance index bd3d31bc4915..c46e68cf9344 100644 --- a/Documentation/vm/balance +++ b/Documentation/vm/balance @@ -75,15 +75,15 @@ Page stealing from process memory and shm is done if stealing the page would alleviate memory pressure on any zone in the page's node that has fallen below its watermark. -pages_min/pages_low/pages_high/low_on_memory/zone_wake_kswapd: These are -per-zone fields, used to determine when a zone needs to be balanced. When -the number of pages falls below pages_min, the hysteric field low_on_memory -gets set. This stays set till the number of free pages becomes pages_high. -When low_on_memory is set, page allocation requests will try to free some -pages in the zone (providing GFP_WAIT is set in the request). Orthogonal -to this, is the decision to poke kswapd to free some zone pages. That -decision is not hysteresis based, and is done when the number of free -pages is below pages_low; in which case zone_wake_kswapd is also set. +watemark[WMARK_MIN/WMARK_LOW/WMARK_HIGH]/low_on_memory/zone_wake_kswapd: These +are per-zone fields, used to determine when a zone needs to be balanced. When +the number of pages falls below watermark[WMARK_MIN], the hysteric field +low_on_memory gets set. This stays set till the number of free pages becomes +watermark[WMARK_HIGH]. When low_on_memory is set, page allocation requests will +try to free some pages in the zone (providing GFP_WAIT is set in the request). +Orthogonal to this, is the decision to poke kswapd to free some zone pages. +That decision is not hysteresis based, and is done when the number of free +pages is below watermark[WMARK_LOW]; in which case zone_wake_kswapd is also set. (Good) Ideas that I have heard: diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c new file mode 100644 index 000000000000..0833f44ba16b --- /dev/null +++ b/Documentation/vm/page-types.c @@ -0,0 +1,698 @@ +/* + * page-types: Tool for querying page flags + * + * Copyright (C) 2009 Intel corporation + * Copyright (C) 2009 Wu Fengguang <fengguang.wu@intel.com> + */ + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <stdint.h> +#include <stdarg.h> +#include <string.h> +#include <getopt.h> +#include <limits.h> +#include <sys/types.h> +#include <sys/errno.h> +#include <sys/fcntl.h> + + +/* + * kernel page flags + */ + +#define KPF_BYTES 8 +#define PROC_KPAGEFLAGS "/proc/kpageflags" + +/* copied from kpageflags_read() */ +#define KPF_LOCKED 0 +#define KPF_ERROR 1 +#define KPF_REFERENCED 2 +#define KPF_UPTODATE 3 +#define KPF_DIRTY 4 +#define KPF_LRU 5 +#define KPF_ACTIVE 6 +#define KPF_SLAB 7 +#define KPF_WRITEBACK 8 +#define KPF_RECLAIM 9 +#define KPF_BUDDY 10 + +/* [11-20] new additions in 2.6.31 */ +#define KPF_MMAP 11 +#define KPF_ANON 12 +#define KPF_SWAPCACHE 13 +#define KPF_SWAPBACKED 14 +#define KPF_COMPOUND_HEAD 15 +#define KPF_COMPOUND_TAIL 16 +#define KPF_HUGE 17 +#define KPF_UNEVICTABLE 18 +#define KPF_NOPAGE 20 + +/* [32-] kernel hacking assistances */ +#define KPF_RESERVED 32 +#define KPF_MLOCKED 33 +#define KPF_MAPPEDTODISK 34 +#define KPF_PRIVATE 35 +#define KPF_PRIVATE_2 36 +#define KPF_OWNER_PRIVATE 37 +#define KPF_ARCH 38 +#define KPF_UNCACHED 39 + +/* [48-] take some arbitrary free slots for expanding overloaded flags + * not part of kernel API + */ +#define KPF_READAHEAD 48 +#define KPF_SLOB_FREE 49 +#define KPF_SLUB_FROZEN 50 +#define KPF_SLUB_DEBUG 51 + +#define KPF_ALL_BITS ((uint64_t)~0ULL) +#define KPF_HACKERS_BITS (0xffffULL << 32) +#define KPF_OVERLOADED_BITS (0xffffULL << 48) +#define BIT(name) (1ULL << KPF_##name) +#define BITS_COMPOUND (BIT(COMPOUND_HEAD) | BIT(COMPOUND_TAIL)) + +static char *page_flag_names[] = { + [KPF_LOCKED] = "L:locked", + [KPF_ERROR] = "E:error", + [KPF_REFERENCED] = "R:referenced", + [KPF_UPTODATE] = "U:uptodate", + [KPF_DIRTY] = "D:dirty", + [KPF_LRU] = "l:lru", + [KPF_ACTIVE] = "A:active", + [KPF_SLAB] = "S:slab", + [KPF_WRITEBACK] = "W:writeback", + [KPF_RECLAIM] = "I:reclaim", + [KPF_BUDDY] = "B:buddy", + + [KPF_MMAP] = "M:mmap", + [KPF_ANON] = "a:anonymous", + [KPF_SWAPCACHE] = "s:swapcache", + [KPF_SWAPBACKED] = "b:swapbacked", + [KPF_COMPOUND_HEAD] = "H:compound_head", + [KPF_COMPOUND_TAIL] = "T:compound_tail", + [KPF_HUGE] = "G:huge", + [KPF_UNEVICTABLE] = "u:unevictable", + [KPF_NOPAGE] = "n:nopage", + + [KPF_RESERVED] = "r:reserved", + [KPF_MLOCKED] = "m:mlocked", + [KPF_MAPPEDTODISK] = "d:mappedtodisk", + [KPF_PRIVATE] = "P:private", + [KPF_PRIVATE_2] = "p:private_2", + [KPF_OWNER_PRIVATE] = "O:owner_private", + [KPF_ARCH] = "h:arch", + [KPF_UNCACHED] = "c:uncached", + + [KPF_READAHEAD] = "I:readahead", + [KPF_SLOB_FREE] = "P:slob_free", + [KPF_SLUB_FROZEN] = "A:slub_frozen", + [KPF_SLUB_DEBUG] = "E:slub_debug", +}; + + +/* + * data structures + */ + +static int opt_raw; /* for kernel developers */ +static int opt_list; /* list pages (in ranges) */ +static int opt_no_summary; /* don't show summary */ +static pid_t opt_pid; /* process to walk */ + +#define MAX_ADDR_RANGES 1024 +static int nr_addr_ranges; +static unsigned long opt_offset[MAX_ADDR_RANGES]; +static unsigned long opt_size[MAX_ADDR_RANGES]; + +#define MAX_BIT_FILTERS 64 +static int nr_bit_filters; +static uint64_t opt_mask[MAX_BIT_FILTERS]; +static uint64_t opt_bits[MAX_BIT_FILTERS]; + +static int page_size; + +#define PAGES_BATCH (64 << 10) /* 64k pages */ +static int kpageflags_fd; +static uint64_t kpageflags_buf[KPF_BYTES * PAGES_BATCH]; + +#define HASH_SHIFT 13 +#define HASH_SIZE (1 << HASH_SHIFT) +#define HASH_MASK (HASH_SIZE - 1) +#define HASH_KEY(flags) (flags & HASH_MASK) + +static unsigned long total_pages; +static unsigned long nr_pages[HASH_SIZE]; +static uint64_t page_flags[HASH_SIZE]; + + +/* + * helper functions + */ + +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +#define min_t(type, x, y) ({ \ + type __min1 = (x); \ + type __min2 = (y); \ + __min1 < __min2 ? __min1 : __min2; }) + +unsigned long pages2mb(unsigned long pages) +{ + return (pages * page_size) >> 20; +} + +void fatal(const char *x, ...) +{ + va_list ap; + + va_start(ap, x); + vfprintf(stderr, x, ap); + va_end(ap); + exit(EXIT_FAILURE); +} + + +/* + * page flag names + */ + +char *page_flag_name(uint64_t flags) +{ + static char buf[65]; + int present; + int i, j; + + for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) { + present = (flags >> i) & 1; + if (!page_flag_names[i]) { + if (present) + fatal("unkown flag bit %d\n", i); + continue; + } + buf[j++] = present ? page_flag_names[i][0] : '_'; + } + + return buf; +} + +char *page_flag_longname(uint64_t flags) +{ + static char buf[1024]; + int i, n; + + for (i = 0, n = 0; i < ARRAY_SIZE(page_flag_names); i++) { + if (!page_flag_names[i]) + continue; + if ((flags >> i) & 1) + n += snprintf(buf + n, sizeof(buf) - n, "%s,", + page_flag_names[i] + 2); + } + if (n) + n--; + buf[n] = '\0'; + + return buf; +} + + +/* + * page list and summary + */ + +void show_page_range(unsigned long offset, uint64_t flags) +{ + static uint64_t flags0; + static unsigned long index; + static unsigned long count; + + if (flags == flags0 && offset == index + count) { + count++; + return; + } + + if (count) + printf("%lu\t%lu\t%s\n", + index, count, page_flag_name(flags0)); + + flags0 = flags; + index = offset; + count = 1; +} + +void show_page(unsigned long offset, uint64_t flags) +{ + printf("%lu\t%s\n", offset, page_flag_name(flags)); +} + +void show_summary(void) +{ + int i; + + printf(" flags\tpage-count MB" + " symbolic-flags\t\t\tlong-symbolic-flags\n"); + + for (i = 0; i < ARRAY_SIZE(nr_pages); i++) { + if (nr_pages[i]) + printf("0x%016llx\t%10lu %8lu %s\t%s\n", + (unsigned long long)page_flags[i], + nr_pages[i], + pages2mb(nr_pages[i]), + page_flag_name(page_flags[i]), + page_flag_longname(page_flags[i])); + } + + printf(" total\t%10lu %8lu\n", + total_pages, pages2mb(total_pages)); +} + + +/* + * page flag filters + */ + +int bit_mask_ok(uint64_t flags) +{ + int i; + + for (i = 0; i < nr_bit_filters; i++) { + if (opt_bits[i] == KPF_ALL_BITS) { + if ((flags & opt_mask[i]) == 0) + return 0; + } else { + if ((flags & opt_mask[i]) != opt_bits[i]) + return 0; + } + } + + return 1; +} + +uint64_t expand_overloaded_flags(uint64_t flags) +{ + /* SLOB/SLUB overload several page flags */ + if (flags & BIT(SLAB)) { + if (flags & BIT(PRIVATE)) + flags ^= BIT(PRIVATE) | BIT(SLOB_FREE); + if (flags & BIT(ACTIVE)) + flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN); + if (flags & BIT(ERROR)) + flags ^= BIT(ERROR) | BIT(SLUB_DEBUG); + } + + /* PG_reclaim is overloaded as PG_readahead in the read path */ + if ((flags & (BIT(RECLAIM) | BIT(WRITEBACK))) == BIT(RECLAIM)) + flags ^= BIT(RECLAIM) | BIT(READAHEAD); + + return flags; +} + +uint64_t well_known_flags(uint64_t flags) +{ + /* hide flags intended only for kernel hacker */ + flags &= ~KPF_HACKERS_BITS; + + /* hide non-hugeTLB compound pages */ + if ((flags & BITS_COMPOUND) && !(flags & BIT(HUGE))) + flags &= ~BITS_COMPOUND; + + return flags; +} + + +/* + * page frame walker + */ + +int hash_slot(uint64_t flags) +{ + int k = HASH_KEY(flags); + int i; + + /* Explicitly reserve slot 0 for flags 0: the following logic + * cannot distinguish an unoccupied slot from slot (flags==0). + */ + if (flags == 0) + return 0; + + /* search through the remaining (HASH_SIZE-1) slots */ + for (i = 1; i < ARRAY_SIZE(page_flags); i++, k++) { + if (!k || k >= ARRAY_SIZE(page_flags)) + k = 1; + if (page_flags[k] == 0) { + page_flags[k] = flags; + return k; + } + if (page_flags[k] == flags) + return k; + } + + fatal("hash table full: bump up HASH_SHIFT?\n"); + exit(EXIT_FAILURE); +} + +void add_page(unsigned long offset, uint64_t flags) +{ + flags = expand_overloaded_flags(flags); + + if (!opt_raw) + flags = well_known_flags(flags); + + if (!bit_mask_ok(flags)) + return; + + if (opt_list == 1) + show_page_range(offset, flags); + else if (opt_list == 2) + show_page(offset, flags); + + nr_pages[hash_slot(flags)]++; + total_pages++; +} + +void walk_pfn(unsigned long index, unsigned long count) +{ + unsigned long batch; + unsigned long n; + unsigned long i; + + if (index > ULONG_MAX / KPF_BYTES) + fatal("index overflow: %lu\n", index); + + lseek(kpageflags_fd, index * KPF_BYTES, SEEK_SET); + + while (count) { + batch = min_t(unsigned long, count, PAGES_BATCH); + n = read(kpageflags_fd, kpageflags_buf, batch * KPF_BYTES); + if (n == 0) + break; + if (n < 0) { + perror(PROC_KPAGEFLAGS); + exit(EXIT_FAILURE); + } + + if (n % KPF_BYTES != 0) + fatal("partial read: %lu bytes\n", n); + n = n / KPF_BYTES; + + for (i = 0; i < n; i++) + add_page(index + i, kpageflags_buf[i]); + + index += batch; + count -= batch; + } +} + +void walk_addr_ranges(void) +{ + int i; + + kpageflags_fd = open(PROC_KPAGEFLAGS, O_RDONLY); + if (kpageflags_fd < 0) { + perror(PROC_KPAGEFLAGS); + exit(EXIT_FAILURE); + } + + if (!nr_addr_ranges) + walk_pfn(0, ULONG_MAX); + + for (i = 0; i < nr_addr_ranges; i++) + walk_pfn(opt_offset[i], opt_size[i]); + + close(kpageflags_fd); +} + + +/* + * user interface + */ + +const char *page_flag_type(uint64_t flag) +{ + if (flag & KPF_HACKERS_BITS) + return "(r)"; + if (flag & KPF_OVERLOADED_BITS) + return "(o)"; + return " "; +} + +void usage(void) +{ + int i, j; + + printf( +"page-types [options]\n" +" -r|--raw Raw mode, for kernel developers\n" +" -a|--addr addr-spec Walk a range of pages\n" +" -b|--bits bits-spec Walk pages with specified bits\n" +#if 0 /* planned features */ +" -p|--pid pid Walk process address space\n" +" -f|--file filename Walk file address space\n" +#endif +" -l|--list Show page details in ranges\n" +" -L|--list-each Show page details one by one\n" +" -N|--no-summary Don't show summay info\n" +" -h|--help Show this usage message\n" +"addr-spec:\n" +" N one page at offset N (unit: pages)\n" +" N+M pages range from N to N+M-1\n" +" N,M pages range from N to M-1\n" +" N, pages range from N to end\n" +" ,M pages range from 0 to M\n" +"bits-spec:\n" +" bit1,bit2 (flags & (bit1|bit2)) != 0\n" +" bit1,bit2=bit1 (flags & (bit1|bit2)) == bit1\n" +" bit1,~bit2 (flags & (bit1|bit2)) == bit1\n" +" =bit1,bit2 flags == (bit1|bit2)\n" +"bit-names:\n" + ); + + for (i = 0, j = 0; i < ARRAY_SIZE(page_flag_names); i++) { + if (!page_flag_names[i]) + continue; + printf("%16s%s", page_flag_names[i] + 2, + page_flag_type(1ULL << i)); + if (++j > 3) { + j = 0; + putchar('\n'); + } + } + printf("\n " + "(r) raw mode bits (o) overloaded bits\n"); +} + +unsigned long long parse_number(const char *str) +{ + unsigned long long n; + + n = strtoll(str, NULL, 0); + + if (n == 0 && str[0] != '0') + fatal("invalid name or number: %s\n", str); + + return n; +} + +void parse_pid(const char *str) +{ + opt_pid = parse_number(str); +} + +void parse_file(const char *name) +{ +} + +void add_addr_range(unsigned long offset, unsigned long size) +{ + if (nr_addr_ranges >= MAX_ADDR_RANGES) + fatal("too much addr ranges\n"); + + opt_offset[nr_addr_ranges] = offset; + opt_size[nr_addr_ranges] = size; + nr_addr_ranges++; +} + +void parse_addr_range(const char *optarg) +{ + unsigned long offset; + unsigned long size; + char *p; + + p = strchr(optarg, ','); + if (!p) + p = strchr(optarg, '+'); + + if (p == optarg) { + offset = 0; + size = parse_number(p + 1); + } else if (p) { + offset = parse_number(optarg); + if (p[1] == '\0') + size = ULONG_MAX; + else { + size = parse_number(p + 1); + if (*p == ',') { + if (size < offset) + fatal("invalid range: %lu,%lu\n", + offset, size); + size -= offset; + } + } + } else { + offset = parse_number(optarg); + size = 1; + } + + add_addr_range(offset, size); +} + +void add_bits_filter(uint64_t mask, uint64_t bits) +{ + if (nr_bit_filters >= MAX_BIT_FILTERS) + fatal("too much bit filters\n"); + + opt_mask[nr_bit_filters] = mask; + opt_bits[nr_bit_filters] = bits; + nr_bit_filters++; +} + +uint64_t parse_flag_name(const char *str, int len) +{ + int i; + + if (!*str || !len) + return 0; + + if (len <= 8 && !strncmp(str, "compound", len)) + return BITS_COMPOUND; + + for (i = 0; i < ARRAY_SIZE(page_flag_names); i++) { + if (!page_flag_names[i]) + continue; + if (!strncmp(str, page_flag_names[i] + 2, len)) + return 1ULL << i; + } + + return parse_number(str); +} + +uint64_t parse_flag_names(const char *str, int all) +{ + const char *p = str; + uint64_t flags = 0; + + while (1) { + if (*p == ',' || *p == '=' || *p == '\0') { + if ((*str != '~') || (*str == '~' && all && *++str)) + flags |= parse_flag_name(str, p - str); + if (*p != ',') + break; + str = p + 1; + } + p++; + } + + return flags; +} + +void parse_bits_mask(const char *optarg) +{ + uint64_t mask; + uint64_t bits; + const char *p; + + p = strchr(optarg, '='); + if (p == optarg) { + mask = KPF_ALL_BITS; + bits = parse_flag_names(p + 1, 0); + } else if (p) { + mask = parse_flag_names(optarg, 0); + bits = parse_flag_names(p + 1, 0); + } else if (strchr(optarg, '~')) { + mask = parse_flag_names(optarg, 1); + bits = parse_flag_names(optarg, 0); + } else { + mask = parse_flag_names(optarg, 0); + bits = KPF_ALL_BITS; + } + + add_bits_filter(mask, bits); +} + + +struct option opts[] = { + { "raw" , 0, NULL, 'r' }, + { "pid" , 1, NULL, 'p' }, + { "file" , 1, NULL, 'f' }, + { "addr" , 1, NULL, 'a' }, + { "bits" , 1, NULL, 'b' }, + { "list" , 0, NULL, 'l' }, + { "list-each" , 0, NULL, 'L' }, + { "no-summary", 0, NULL, 'N' }, + { "help" , 0, NULL, 'h' }, + { NULL , 0, NULL, 0 } +}; + +int main(int argc, char *argv[]) +{ + int c; + + page_size = getpagesize(); + + while ((c = getopt_long(argc, argv, + "rp:f:a:b:lLNh", opts, NULL)) != -1) { + switch (c) { + case 'r': + opt_raw = 1; + break; + case 'p': + parse_pid(optarg); + break; + case 'f': + parse_file(optarg); + break; + case 'a': + parse_addr_range(optarg); + break; + case 'b': + parse_bits_mask(optarg); + break; + case 'l': + opt_list = 1; + break; + case 'L': + opt_list = 2; + break; + case 'N': + opt_no_summary = 1; + break; + case 'h': + usage(); + exit(0); + default: + usage(); + exit(1); + } + } + + if (opt_list == 1) + printf("offset\tcount\tflags\n"); + if (opt_list == 2) + printf("offset\tflags\n"); + + walk_addr_ranges(); + + if (opt_list == 1) + show_page_range(0, 0); /* drain the buffer */ + + if (opt_no_summary) + return 0; + + if (opt_list) + printf("\n\n"); + + show_summary(); + + return 0; +} diff --git a/Documentation/vm/pagemap.txt b/Documentation/vm/pagemap.txt index ce72c0fe6177..600a304a828c 100644 --- a/Documentation/vm/pagemap.txt +++ b/Documentation/vm/pagemap.txt @@ -12,9 +12,9 @@ There are three components to pagemap: value for each virtual page, containing the following data (from fs/proc/task_mmu.c, above pagemap_read): - * Bits 0-55 page frame number (PFN) if present + * Bits 0-54 page frame number (PFN) if present * Bits 0-4 swap type if swapped - * Bits 5-55 swap offset if swapped + * Bits 5-54 swap offset if swapped * Bits 55-60 page shift (page size = 1<<page shift) * Bit 61 reserved for future use * Bit 62 page swapped @@ -36,7 +36,7 @@ There are three components to pagemap: * /proc/kpageflags. This file contains a 64-bit set of flags for each page, indexed by PFN. - The flags are (from fs/proc/proc_misc, above kpageflags_read): + The flags are (from fs/proc/page.c, above kpageflags_read): 0. LOCKED 1. ERROR @@ -49,6 +49,68 @@ There are three components to pagemap: 8. WRITEBACK 9. RECLAIM 10. BUDDY + 11. MMAP + 12. ANON + 13. SWAPCACHE + 14. SWAPBACKED + 15. COMPOUND_HEAD + 16. COMPOUND_TAIL + 16. HUGE + 18. UNEVICTABLE + 20. NOPAGE + +Short descriptions to the page flags: + + 0. LOCKED + page is being locked for exclusive access, eg. by undergoing read/write IO + + 7. SLAB + page is managed by the SLAB/SLOB/SLUB/SLQB kernel memory allocator + When compound page is used, SLUB/SLQB will only set this flag on the head + page; SLOB will not flag it at all. + +10. BUDDY + a free memory block managed by the buddy system allocator + The buddy system organizes free memory in blocks of various orders. + An order N block has 2^N physically contiguous pages, with the BUDDY flag + set for and _only_ for the first page. + +15. COMPOUND_HEAD +16. COMPOUND_TAIL + A compound page with order N consists of 2^N physically contiguous pages. + A compound page with order 2 takes the form of "HTTT", where H donates its + head page and T donates its tail page(s). The major consumers of compound + pages are hugeTLB pages (Documentation/vm/hugetlbpage.txt), the SLUB etc. + memory allocators and various device drivers. However in this interface, + only huge/giga pages are made visible to end users. +17. HUGE + this is an integral part of a HugeTLB page + +20. NOPAGE + no page frame exists at the requested address + + [IO related page flags] + 1. ERROR IO error occurred + 3. UPTODATE page has up-to-date data + ie. for file backed page: (in-memory data revision >= on-disk one) + 4. DIRTY page has been written to, hence contains new data + ie. for file backed page: (in-memory data revision > on-disk one) + 8. WRITEBACK page is being synced to disk + + [LRU related page flags] + 5. LRU page is in one of the LRU lists + 6. ACTIVE page is in the active LRU list +18. UNEVICTABLE page is in the unevictable (non-)LRU list + It is somehow pinned and not a candidate for LRU page reclaims, + eg. ramfs pages, shmctl(SHM_LOCK) and mlock() memory segments + 2. REFERENCED page has been referenced since last LRU list enqueue/requeue + 9. RECLAIM page will be reclaimed soon after its pageout IO completed +11. MMAP a memory mapped page +12. ANON a memory mapped page that is not part of a file +13. SWAPCACHE page is mapped to swap space, ie. has an associated swap entry +14. SWAPBACKED page is backed by swap/RAM + +The page-types tool in this directory can be used to query the above flags. Using pagemap to do something useful: diff --git a/Documentation/watchdog/hpwdt.txt b/Documentation/watchdog/hpwdt.txt new file mode 100644 index 000000000000..127839e53043 --- /dev/null +++ b/Documentation/watchdog/hpwdt.txt @@ -0,0 +1,84 @@ +Last reviewed: 06/02/2009 + + HP iLO2 NMI Watchdog Driver + NMI sourcing for iLO2 based ProLiant Servers + Documentation and Driver by + Thomas Mingarelli <thomas.mingarelli@hp.com> + + The HP iLO2 NMI Watchdog driver is a kernel module that provides basic + watchdog functionality and the added benefit of NMI sourcing. Both the + watchdog functionality and the NMI sourcing capability need to be enabled + by the user. Remember that the two modes are not dependant on one another. + A user can have the NMI sourcing without the watchdog timer and vice-versa. + + Watchdog functionality is enabled like any other common watchdog driver. That + is, an application needs to be started that kicks off the watchdog timer. A + basic application exists in the Documentation/watchdog/src directory called + watchdog-test.c. Simply compile the C file and kick it off. If the system + gets into a bad state and hangs, the HP ProLiant iLO 2 timer register will + not be updated in a timely fashion and a hardware system reset (also known as + an Automatic Server Recovery (ASR)) event will occur. + + The hpwdt driver also has three (3) module parameters. They are the following: + + soft_margin - allows the user to set the watchdog timer value + allow_kdump - allows the user to save off a kernel dump image after an NMI + nowayout - basic watchdog parameter that does not allow the timer to + be restarted or an impending ASR to be escaped. + + NOTE: More information about watchdog drivers in general, including the ioctl + interface to /dev/watchdog can be found in + Documentation/watchdog/watchdog-api.txt and Documentation/IPMI.txt. + + The NMI sourcing capability is disabled when the driver discovers that the + nmi_watchdog is turned on (nmi_watchdog = 1). This is due to the inability to + distinguish between "NMI Watchdog Ticks" and "HW generated NMI events" in the + Linux kernel. What this means is that the hpwdt nmi handler code is called + each time the NMI signal fires off. This could amount to several thousands of + NMIs in a matter of seconds. If a user sees the Linux kernel's "dazed and + confused" message in the logs or if the system gets into a hung state, then + the user should reboot with nmi_watchdog=0. + + 1. If the kernel has not been booted with nmi_watchdog turned off then + edit /boot/grub/menu.lst and place the nmi_watchdog=0 at the end of the + currently booting kernel line. + 2. reboot the sever + + Now, the hpwdt can successfully receive and source the NMI and provide a log + message that details the reason for the NMI (as determined by the HP BIOS). + + Below is a list of NMIs the HP BIOS understands along with the associated + code (reason): + + No source found 00h + + Uncorrectable Memory Error 01h + + ASR NMI 1Bh + + PCI Parity Error 20h + + NMI Button Press 27h + + SB_BUS_NMI 28h + + ILO Doorbell NMI 29h + + ILO IOP NMI 2Ah + + ILO Watchdog NMI 2Bh + + Proc Throt NMI 2Ch + + Front Side Bus NMI 2Dh + + PCI Express Error 2Fh + + DMA controller NMI 30h + + Hypertransport/CSI Error 31h + + + + -- Tom Mingarelli + (thomas.mingarelli@hp.com) |