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2010-04-06Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: Force MSI irq handlers to run with interrupts disabled
2010-03-31genirq: Force MSI irq handlers to run with interrupts disabledThomas Gleixner
Network folks reported that directing all MSI-X vectors of their multi queue NICs to a single core can cause interrupt stack overflows when enough interrupts fire at the same time. This is caused by the fact that we run interrupt handlers by default with interrupts enabled unless the driver reuqests the interrupt with the IRQF_DISABLED set. The NIC handlers do not set this flag, so simultaneous interrupts can nest unlimited and cause the stack overflow. The only safe counter measure is to run the interrupt handlers with interrupts disabled. We can't switch to this mode in general right now, but it is safe to do so for MSI interrupts. Force IRQF_DISABLED for MSI interrupt handlers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@osdl.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: David Miller <davem@davemloft.net> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: stable@kernel.org
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-26Merge branch 'irq-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: Move two IRQ functions from .init.text to .text genirq: Protect access to irq_desc->action in can_request_irq() genirq: Prevent oneshot irq thread race
2010-03-24genirq: Move two IRQ functions from .init.text to .textHenrik Kretzschmar
Both functions should not be marked as __init, since they be called from modules after the init section is freed. Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Kosina <jkosina@suse.cz> LKML-Reference: <1269431961-5731-1-git-send-email-henne@nachtwindheim.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-03-24genirq: Protect access to irq_desc->action in can_request_irq()Thomas Gleixner
can_request_irq() accesses and dereferences irq_desc->action w/o holding irq_desc->lock. So action can be freed on another CPU before it's dereferenced. Unlikely, but ... Protect it with desc->lock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-03-10genirq: Prevent oneshot irq thread raceThomas Gleixner
Lars-Peter pointed out that the oneshot threaded interrupt handler code has the following race: CPU0 CPU1 hande_level_irq(irq X) mask_ack_irq(irq X) handle_IRQ_event(irq X) wake_up(thread_handler) thread handler(irq X) runs finalize_oneshot(irq X) does not unmask due to !(desc->status & IRQ_MASKED) return from irq does not unmask due to (desc->status & IRQ_ONESHOT) This leaves the interrupt line masked forever. The reason for this is the inconsistent handling of the IRQ_MASKED flag. Instead of setting it in the mask function the oneshot support sets the flag after waking up the irq thread. The solution for this is to set/clear the IRQ_MASKED status whenever we mask/unmask an interrupt line. That's the easy part, but that cleanup opens another race: CPU0 CPU1 hande_level_irq(irq) mask_ack_irq(irq) handle_IRQ_event(irq) wake_up(thread_handler) thread handler(irq) runs finalize_oneshot_irq(irq) unmask(irq) irq triggers again handle_level_irq(irq) mask_ack_irq(irq) return from irq due to IRQ_INPROGRESS return from irq does not unmask due to (desc->status & IRQ_ONESHOT) This requires that we synchronize finalize_oneshot_irq() with the primary handler. If IRQ_INPROGESS is set we wait until the primary handler on the other CPU has returned before unmasking the interrupt line again. We probably have never seen that problem because it does not happen on UP and on SMP the irqbalancer protects us by pinning the primary handler and the thread to the same CPU. Reported-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org
2010-03-08Merge branch 'for-next' into for-linusJiri Kosina
Conflicts: Documentation/filesystems/proc.txt arch/arm/mach-u300/include/mach/debug-macro.S drivers/net/qlge/qlge_ethtool.c drivers/net/qlge/qlge_main.c drivers/net/typhoon.c
2010-02-17sparseirq: Use radix_tree instead of ptrs arrayYinghai Lu
Use radix_tree irq_desc_tree instead of irq_desc_ptrs. -v2: according to Eric and cyrill to use radix_tree_lookup_slot and radix_tree_replace_slot Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-32-git-send-email-yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-17sparseirq: Change irq_desc_ptrs to staticYinghai Lu
Add replace_irq_desc() instead of poking at the array directly. -v2: remove unneeded boundary check in replace_irq_desc Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-31-git-send-email-yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-17irq: Remove unnecessary bootmem codeYinghai Lu
mem_init is moved early already. Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-29-git-send-email-yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-15tree-wide: fix typos "ass?o[sc]iac?te" -> "associate" in commentsUwe Kleine-König
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-11devres/irq: Fix devm_irq_match commentJean Delvare
Fix the reference (in comment). Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-10x86: Avoid race condition in pci_enable_msix()Brandon Phiilps
Keep chip_data in create_irq_nr and destroy_irq. When two drivers are setting up MSI-X at the same time via pci_enable_msix() there is a race. See this dmesg excerpt: [ 85.170610] ixgbe 0000:02:00.1: irq 97 for MSI/MSI-X [ 85.170611] alloc irq_desc for 99 on node -1 [ 85.170613] igb 0000:08:00.1: irq 98 for MSI/MSI-X [ 85.170614] alloc kstat_irqs on node -1 [ 85.170616] alloc irq_2_iommu on node -1 [ 85.170617] alloc irq_desc for 100 on node -1 [ 85.170619] alloc kstat_irqs on node -1 [ 85.170621] alloc irq_2_iommu on node -1 [ 85.170625] ixgbe 0000:02:00.1: irq 99 for MSI/MSI-X [ 85.170626] alloc irq_desc for 101 on node -1 [ 85.170628] igb 0000:08:00.1: irq 100 for MSI/MSI-X [ 85.170630] alloc kstat_irqs on node -1 [ 85.170631] alloc irq_2_iommu on node -1 [ 85.170635] alloc irq_desc for 102 on node -1 [ 85.170636] alloc kstat_irqs on node -1 [ 85.170639] alloc irq_2_iommu on node -1 [ 85.170646] BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 As you can see igb and ixgbe are both alternating on create_irq_nr() via pci_enable_msix() in their probe function. ixgbe: While looping through irq_desc_ptrs[] via create_irq_nr() ixgbe choses irq_desc_ptrs[102] and exits the loop, drops vector_lock and calls dynamic_irq_init. Then it sets irq_desc_ptrs[102]->chip_data = NULL via dynamic_irq_init(). igb: Grabs the vector_lock now and starts looping over irq_desc_ptrs[] via create_irq_nr(). It gets to irq_desc_ptrs[102] and does this: cfg_new = irq_desc_ptrs[102]->chip_data; if (cfg_new->vector != 0) continue; This hits the NULL deref. Another possible race exists via pci_disable_msix() in a driver or in the number of error paths that call free_msi_irqs(): destroy_irq() dynamic_irq_cleanup() which sets desc->chip_data = NULL ...race window... desc->chip_data = cfg; Remove the save and restore code for cfg in create_irq_nr() and destroy_irq() and take the desc->lock when checking the irq_cfg. Reported-and-analyzed-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-3-git-send-email-yinghai@kernel.org> Signed-off-by: Brandon Phililps <bphilips@suse.de> Cc: stable@kernel.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-05devres: typo fix s/dev/devm/Baruch Siach
Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-14genirq: Convert irq_desc.lock to raw_spinlockThomas Gleixner
Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
2009-12-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (42 commits) tree-wide: fix misspelling of "definition" in comments reiserfs: fix misspelling of "journaled" doc: Fix a typo in slub.txt. inotify: remove superfluous return code check hdlc: spelling fix in find_pvc() comment doc: fix regulator docs cut-and-pasteism mtd: Fix comment in Kconfig doc: Fix IRQ chip docs tree-wide: fix assorted typos all over the place drivers/ata/libata-sff.c: comment spelling fixes fix typos/grammos in Documentation/edac.txt sysctl: add missing comments fs/debugfs/inode.c: fix comment typos sgivwfb: Make use of ARRAY_SIZE. sky2: fix sky2_link_down copy/paste comment error tree-wide: fix typos "couter" -> "counter" tree-wide: fix typos "offest" -> "offset" fix kerneldoc for set_irq_msi() spidev: fix double "of of" in comment comment typo fix: sybsystem -> subsystem ...
2009-12-08Merge branches 'timers-for-linus-ntp' and 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-for-linus-ntp' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: ntp: Provide compability defines (You say MOD_NANO, I say ADJ_NANO) * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: do not execute DEBUG_SHIRQ when irq setup failed
2009-12-07Merge branch 'for-next' into for-linusJiri Kosina
Conflicts: kernel/irq/chip.c
2009-12-05Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: Fix spurious irq seqfile conversion genirq: switch /proc/irq/*/spurious to seq_file irq: Do not attempt to create subdirectories if /proc/irq/<irq> failed irq: Remove unused debug_poll_all_shared_irqs() irq: Fix docbook comments irq: trivial: Fix typo in comment for #endif
2009-12-04tree-wide: fix typos "couter" -> "counter"Uwe Kleine-König
This patch was generated by git grep -E -i -l 'couter' | xargs -r perl -p -i -e 's/couter/counter/' Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04fix kerneldoc for set_irq_msi()Liuweni
Signed-off-by: Liuweni <qingshenlwy@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-11-20genirq: Fix spurious irq seqfile conversionThomas Gleixner
single_open data argument must be PDE(inode)->data instead of NULL otherwise seq_file->private is always NULL and we always read the spurious data of irq 0. Reported-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-11-18genirq: switch /proc/irq/*/spurious to seq_fileAlexey Dobriyan
[ tglx: compacted it a bit ] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> LKML-Reference: <20090828181743.GA14050@x200.localdomain> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-11-08irq: Do not attempt to create subdirectories if /proc/irq/<irq> failedCyrill Gorcunov
If a parent directory (ie /proc/irq/<irq>) could not be created we should not attempt to create subdirectories. Otherwise it would lead that "smp_affinity" and "spurious" entries are may be registered under /proc root instead of a proper place. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <20091026202811.GD5321@lenovo> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-07genirq: try_one_irq() must be called with irq disabledYong Zhang
Prarit reported: ================================= [ INFO: inconsistent lock state ] 2.6.32-rc5 #1 --------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. swapper/0 [HC0[0]:SC1[1]:HE1:SE0] takes: (&irq_desc_lock_class){?.-...}, at: [<ffffffff810c264e>] try_one_irq+0x32/0x138 {IN-HARDIRQ-W} state was registered at: [<ffffffff81095160>] __lock_acquire+0x2fc/0xd5d [<ffffffff81095cb4>] lock_acquire+0xf3/0x12d [<ffffffff814cdadd>] _spin_lock+0x40/0x89 [<ffffffff810c3389>] handle_level_irq+0x30/0x105 [<ffffffff81014e0e>] handle_irq+0x95/0xb7 [<ffffffff810141bd>] do_IRQ+0x6a/0xe0 [<ffffffff81012813>] ret_from_intr+0x0/0x16 irq event stamp: 195096 hardirqs last enabled at (195096): [<ffffffff814cd7f7>] _spin_unlock_irq+0x3a/0x5c hardirqs last disabled at (195095): [<ffffffff814cdbdd>] _spin_lock_irq+0x29/0x95 softirqs last enabled at (195088): [<ffffffff81068c92>] __do_softirq+0x1c1/0x1ef softirqs last disabled at (195093): [<ffffffff8101304c>] call_softirq+0x1c/0x30 other info that might help us debug this: 1 lock held by swapper/0: #0: (kernel/irq/spurious.c:21){+.-...}, at: [<ffffffff81070cf2>] run_timer_softirq+0x1a9/0x315 stack backtrace: Pid: 0, comm: swapper Not tainted 2.6.32-rc5 #1 Call Trace: <IRQ> [<ffffffff81093e94>] valid_state+0x187/0x1ae [<ffffffff81093fe4>] mark_lock+0x129/0x253 [<ffffffff810951d4>] __lock_acquire+0x370/0xd5d [<ffffffff81095cb4>] lock_acquire+0xf3/0x12d [<ffffffff814cdadd>] _spin_lock+0x40/0x89 [<ffffffff810c264e>] try_one_irq+0x32/0x138 [<ffffffff810c2795>] poll_all_shared_irqs+0x41/0x6d [<ffffffff810c27dd>] poll_spurious_irqs+0x1c/0x49 [<ffffffff81070d82>] run_timer_softirq+0x239/0x315 [<ffffffff81068bd3>] __do_softirq+0x102/0x1ef [<ffffffff8101304c>] call_softirq+0x1c/0x30 [<ffffffff81014b65>] do_softirq+0x59/0xca [<ffffffff810686ad>] irq_exit+0x58/0xae [<ffffffff81029b84>] smp_apic_timer_interrupt+0x94/0xba [<ffffffff81012a33>] apic_timer_interrupt+0x13/0x20 The reason is that try_one_irq() is called from hardirq context with interrupts disabled and from softirq context (poll_all_shared_irqs()) with interrupts enabled. Disable interrupts before calling it from poll_all_shared_irqs(). Reported-and-tested-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> LKML-Reference: <1257563773-4620-1-git-send-email-yong.zhang0@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-11-04irq: Remove unused debug_poll_all_shared_irqs()Thomas Gleixner
commit 74296a8ed added this function for debug purposes, but it was never used for anything. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-11-04irq: Fix docbook commentsLiuweni
Fix docbook comments to match the actual function names (set_irq_msi, handle_percpu_irq). Signed-off-by: Liuwenyi <qingshenlwy@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-10-11headers: remove sched.h from interrupt.hAlexey Dobriyan
After m68k's task_thread_info() doesn't refer to current, it's possible to remove sched.h from interrupt.h and not break m68k! Many thanks to Heiko Carstens for allowing this. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-09-11Merge branch 'irq-threaded-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-threaded-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq: Do not mask oneshot edge type interrupts genirq: Support nested threaded irq handling genirq: Add buslock support genirq: Add oneshot support
2009-08-29irq: Make sure irq_desc for legacy irq get correct node settingYinghai Lu
when there is no ram on node 0. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> LKML-Reference: <4A95C32D.5040605@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-27genirq: Do not mask oneshot edge type interruptsThomas Gleixner
Masking oneshot edge type interrupts is wrong as we might lose an interrupt which is issued when the threaded handler is handling the device. We can keep the irq unmasked safely as with edge type interrupts there is no danger of interrupt floods. If the threaded handler has not yet finished then IRQTF_RUNTHREAD is set which will keep the handler thread active. Debugged and verified in preempt-rt. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-25Merge commit 'v2.6.31-rc7' into irq/coreIngo Molnar
Merge reason: move from an -rc2 base to -rc7. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18genirq: Wake up irq thread after action has been installedThomas Gleixner
The wake_up_process() of the new irq thread in __setup_irq() is too early as the irqaction is not yet fully initialized especially action->irq is not yet set. The interrupt thread might dereference the wrong irq descriptor. Move the wakeup after the action is installed and action->irq has been set. Reported-by: Michael Buesch <mb@bu3sch.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Buesch <mb@bu3sch.de>
2009-08-17genirq: Support nested threaded irq handlingThomas Gleixner
Interrupt chips which are behind a slow bus (i2c, spi ...) and demultiplex other interrupt sources need to run their interrupt handler in a thread. The demultiplexed interrupt handlers need to run in thread context as well and need to finish before the demux handler thread can reenable the interrupt line. So the easiest way is to run the sub device handlers in the context of the demultiplexing handler thread. To avoid that a separate thread is created for the subdevices the function set_nested_irq_thread() is provided which sets the IRQ_NESTED_THREAD flag in the interrupt descriptor. A driver which calls request_threaded_irq() must not be aware of the fact that the threaded handler is called in the context of the demultiplexing handler thread. The setup code checks the IRQ_NESTED_THREAD flag which was set from the irq chip setup code and does not setup a separate thread for the interrupt. The primary function which is provided by the device driver is replaced by an internal dummy function which warns when it is called. For the demultiplexing handler a helper function handle_nested_irq() is provided which calls the demux interrupt thread function in the context of the caller and does the proper interrupt accounting and takes the interrupt disabled status of the demultiplexed subdevice into account. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-17genirq: Add buslock supportThomas Gleixner
Some interrupt chips are connected to a "slow" bus (i2c, spi ...). The bus access needs to sleep and therefor cannot be called in atomic contexts. Some of the generic interrupt management functions like disable_irq(), enable_irq() ... call interrupt chip functions with the irq_desc->lock held and interrupts disabled. This does not work for such devices. Provide a separate synchronization mechanism for such interrupt chips. The irq_chip structure is extended by two optional functions (bus_lock and bus_sync_and_unlock). The idea is to serialize the bus access for those operations in the core code so that drivers which are behind that bus operated interrupt controller do not have to worry about it and just can use the normal interfaces. To achieve this we add two function pointers to the irq_chip: bus_lock and bus_sync_unlock. bus_lock() is called to serialize access to the interrupt controller bus. Now the core code can issue chip->mask/unmask ... commands without changing the fast path code at all. The chip implementation merily stores that information in a chip private data structure and returns. No bus interaction as these functions are called from atomic context. After that bus_sync_unlock() is called outside the atomic context. Now the chip implementation issues the bus commands, waits for completion and unlocks the interrupt controller bus. The irq_chip implementation as pseudo code: struct irq_chip_data { struct mutex mutex; unsigned int irq_offset; unsigned long mask; unsigned long mask_status; } static void bus_lock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); mutex_lock(&data->mutex); } static void mask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask |= (1 << irq); } static void unmask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask &= ~(1 << irq); } static void bus_sync_unlock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); if (data->mask != data->mask_status) { do_bus_magic_to_set_mask(data->mask); data->mask_status = data->mask; } mutex_unlock(&data->mutex); } The device drivers can use request_threaded_irq, free_irq, disable_irq and enable_irq as usual with the only restriction that the calls need to come from non atomic context. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-17genirq: Add oneshot supportThomas Gleixner
For threaded interrupt handlers we expect the hard interrupt handler part to mask the interrupt on the originating device. The interrupt line itself is reenabled after the hard interrupt handler has executed. This requires access to the originating device from hard interrupt context which is not always possible. There are devices which can only be accessed via a bus (i2c, spi, ...). The bus access requires thread context. For such devices we need to keep the interrupt line masked until the threaded handler has executed. Add a new flag IRQF_ONESHOT which allows drivers to request that the interrupt is not unmasked after the hard interrupt context handler has been executed and the thread has been woken. The interrupt line is unmasked after the thread handler function has been executed. Note that for now IRQF_ONESHOT cannot be used with IRQF_SHARED to avoid complex accounting mechanisms. For oneshot interrupts the primary handler simply returns IRQ_WAKE_THREAD and does nothing else. A generic implementation irq_default_primary_handler() is provided to avoid useless copies all over the place. It is automatically installed when request_threaded_irq() is called with handler=NULL and thread_fn!=NULL. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-13genirq: prevent wakeup of freed irq threadLinus Torvalds
free_irq() can remove an irqaction while the corresponding interrupt is in progress, but free_irq() sets action->thread to NULL unconditionally, which might lead to a NULL pointer dereference in handle_IRQ_event() when the hard interrupt context tries to wake up the handler thread. Prevent this by moving the thread stop after synchronize_irq(). No need to set action->thread to NULL either as action is going to be freed anyway. This fixes a boot crash reported against preempt-rt which uses the mainline irq threads code to implement full irq threading. [ tglx: removed local irqthread variable ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-09irq: Remove superfluous NULL pointer check in check_irq_resend()Bartlomiej Zolnierkiewicz
This takes care of the following entry from Dan's list: kernel/irq/resend.c +73 check_irq_resend(17) warning: variable derefenced before check 'desc->chip' Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Eugene Teo <eteo@redhat.com> Cc: Julia Lawall <julia@diku.dk> LKML-Reference: <200908062146.03638.bzolnier@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-08x86/irq: Fix move_irq_desc() for nodes without ramYinghai Lu
Don't move it if target node is -1. Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4A785B5D.4070702@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-04irq: Clean up by removing irqfixup MODULE_PARM_DESC()Jiri Slaby
It's wrong (the parm takes no arguments) and compile-time wiped away anyway (due to !MODULE). Signed-off-by: Jiri Slaby <jirislaby@gmail.com> LKML-Reference: <1248991326-26267-1-git-send-email-jirislaby@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-22genirq: Fix UP compile failure caused by irq_thread_check_affinityBruno Premont
Since genirq: Delegate irq affinity setting to the irq thread (591d2fb02ea80472d846c0b8507007806bdd69cc) compilation with CONFIG_SMP=n fails with following error: /usr/src/linux-2.6/kernel/irq/manage.c: In function 'irq_thread_check_affinity': /usr/src/linux-2.6/kernel/irq/manage.c:475: error: 'struct irq_desc' has no member named 'affinity' make[4]: *** [kernel/irq/manage.o] Error 1 That commit adds a new function irq_thread_check_affinity() which uses struct irq_desc.affinity which is only available for CONFIG_SMP=y. Move that function under #ifdef CONFIG_SMP. [ tglx@brownpaperbag: compile and boot tested on UP and SMP ] Signed-off-by: Bruno Premont <bonbons@linux-vserver.org> LKML-Reference: <20090722222232.2eb3e1c4@neptune.home> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-07-21genirq: Delegate irq affinity setting to the irq threadThomas Gleixner
irq_set_thread_affinity() calls set_cpus_allowed_ptr() which might sleep, but irq_set_thread_affinity() is called with desc->lock held and can be called from hard interrupt context as well. The code has another bug as it does not hold a ref on the task struct as required by set_cpus_allowed_ptr(). Just set the IRQTF_AFFINITY bit in action->thread_flags. The next time the thread runs it migrates itself. Solves all of the above problems nicely. Add kerneldoc to irq_set_thread_affinity() while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <new-submission>
2009-07-05genirq: Fix comment describing suspend_device_irqs()Rafael J. Wysocki
The kerneldoc comment describing suspend_device_irqs() is currently misleading, because generally the function doesn't really disable interrupt lines at the chip level. Replace it with a more accurate one. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> LKML-Reference: <200907050022.35117.rjw@sisk.pl> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-06-20Merge branch 'irq-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: genirq, irq.h: Fix kernel-doc warnings genirq: fix comment to say IRQ_WAKE_THREAD
2009-06-12irq: slab alloc for default irq_affinityYinghai Lu
Ingo had [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: at mm/bootmem.c:537 alloc_arch_preferred_bootmem+0x2b/0x71() [ 0.000000] Hardware name: System Product Name [ 0.000000] Modules linked in: [ 0.000000] Pid: 0, comm: swapper Tainted: G W 2.6.30-tip-03087-g0bb2618-dirty #52506 [ 0.000000] Call Trace: [ 0.000000] [<81032588>] warn_slowpath_common+0x60/0x90 [ 0.000000] [<810325c5>] warn_slowpath_null+0xd/0x10 [ 0.000000] [<819d1bc0>] alloc_arch_preferred_bootmem+0x2b/0x71 [ 0.000000] [<819d1c31>] ___alloc_bootmem_nopanic+0x2b/0x9a [ 0.000000] [<81050a0a>] ? lock_release+0xac/0xb2 [ 0.000000] [<819d1d4c>] ___alloc_bootmem+0xe/0x2d [ 0.000000] [<819d1e9f>] __alloc_bootmem+0xa/0xc [ 0.000000] [<819d7c63>] alloc_bootmem_cpumask_var+0x21/0x26 [ 0.000000] [<819d0cc8>] early_irq_init+0x15/0x10d [ 0.000000] [<819bb75a>] start_kernel+0x167/0x326 [ 0.000000] [<819bb06b>] __init_begin+0x6b/0x70 [ 0.000000] ---[ end trace 4eaa2a86a8e2da23 ]--- [ 0.000000] NR_IRQS:2304 nr_irqs:424 [ 0.000000] CPU 0 irqstacks, hard=821e6000 soft=821e7000 we need to update init_irq_default_affinity Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-06-11irq: use kcalloc() instead of the bootmem allocatorPekka Enberg
Fixes the following problem: [ 0.000000] Experimental hierarchical RCU init done. [ 0.000000] NR_IRQS:4352 nr_irqs:256 [ 0.000000] ------------[ cut here ]------------ [ 0.000000] WARNING: at mm/bootmem.c:537 alloc_arch_preferred_bootmem+0x40/0x7e() [ 0.000000] Hardware name: To Be Filled By O.E.M. [ 0.000000] Pid: 0, comm: swapper Not tainted 2.6.30-tip-02161-g7a74539-dirty #59709 [ 0.000000] Call Trace: [ 0.000000] [<ffffffff823f8c8e>] ? alloc_arch_preferred_bootmem+0x40/0x7e [ 0.000000] [<ffffffff81067168>] warn_slowpath_common+0x88/0xcb [ 0.000000] [<ffffffff810671d2>] warn_slowpath_null+0x27/0x3d [ 0.000000] [<ffffffff823f8c8e>] alloc_arch_preferred_bootmem+0x40/0x7e [ 0.000000] [<ffffffff823f9307>] ___alloc_bootmem_nopanic+0x4e/0xec [ 0.000000] [<ffffffff823f93c5>] ___alloc_bootmem+0x20/0x61 [ 0.000000] [<ffffffff823f962e>] __alloc_bootmem+0x1e/0x34 [ 0.000000] [<ffffffff823f757c>] early_irq_init+0x6d/0x118 [ 0.000000] [<ffffffff823e0140>] ? early_idt_handler+0x0/0x71 [ 0.000000] [<ffffffff823e0cf7>] start_kernel+0x192/0x394 [ 0.000000] [<ffffffff823e0140>] ? early_idt_handler+0x0/0x71 [ 0.000000] [<ffffffff823e02ad>] x86_64_start_reservations+0xb4/0xcf [ 0.000000] [<ffffffff823e0000>] ? __init_begin+0x0/0x140 [ 0.000000] [<ffffffff823e0420>] x86_64_start_kernel+0x158/0x17b [ 0.000000] ---[ end trace a7919e7f17c0a725 ]--- [ 0.000000] Fast TSC calibration using PIT [ 0.000000] Detected 2002.510 MHz processor. [ 0.004000] Console: colour VGA+ 80x25 Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-06-11irq/cpumask: make memoryless node zero happyYinghai Lu
Don't hardcode to node zero for early boot IRQ setup memory allocations. [ penberg@cs.helsinki.fi: minor cleanups ] Cc: Ingo Molnar <mingo@elte.hu> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-06-10Merge branch 'tracing-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits) Revert "x86, bts: reenable ptrace branch trace support" tracing: do not translate event helper macros in print format ftrace/documentation: fix typo in function grapher name tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK tracing: add protection around module events unload tracing: add trace_seq_vprint interface tracing: fix the block trace points print size tracing/events: convert block trace points to TRACE_EVENT() ring-buffer: fix ret in rb_add_time_stamp ring-buffer: pass in lockdep class key for reader_lock tracing: add annotation to what type of stack trace is recorded tracing: fix multiple use of __print_flags and __print_symbolic tracing/events: fix output format of user stack tracing/events: fix output format of kernel stack tracing/trace_stack: fix the number of entries in the header ring-buffer: discard timestamps that are at the start of the buffer ring-buffer: try to discard unneeded timestamps ring-buffer: fix bug in ring_buffer_discard_commit ftrace: do not profile functions when disabled tracing: make trace pipe recognize latency format flag ...
2009-05-23sparseirq: Allow early irq_desc allocationPaul Mundt
Presently non-legacy IRQs have their irq_desc allocated with kzalloc_node(). This assumes that all callers of irq_to_desc_node_alloc() will be sufficiently late in the boot process that kmalloc is available. While porting sparseirq support to sh this blew up immediately, as at the time that we register the CPU's interrupt vector map only bootmem is available. Check slab_is_available() to work out which path to use. [ Impact: fix SH early boot crash with sparseirq enabled ] Signed-off-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Yinghai Lu <yinghai@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> LKML-Reference: <20090522014008.GA2806@linux-sh.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>