From e9e9250bc78e7f6342517214c0178a529807964b Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 1 Sep 2009 10:34:37 +0200 Subject: sched: Scale down cpu_power due to RT tasks Keep an average on the amount of time spend on RT tasks and use that fraction to scale down the cpu_power for regular tasks. Signed-off-by: Peter Zijlstra Tested-by: Andreas Herrmann Acked-by: Andreas Herrmann Acked-by: Gautham R Shenoy Cc: Balbir Singh LKML-Reference: <20090901083826.287778431@chello.nl> Signed-off-by: Ingo Molnar --- kernel/sysctl.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'kernel/sysctl.c') diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 58be76017fd0..6c9836ef4b47 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -330,6 +330,14 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = &proc_dointvec, }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_time_avg", + .data = &sysctl_sched_time_avg, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, { .ctl_name = CTL_UNNUMBERED, .procname = "timer_migration", -- cgit v1.2.3 From 2bba22c50b06abe9fd0d23933b1e64d35b419262 Mon Sep 17 00:00:00 2001 From: Mike Galbraith Date: Wed, 9 Sep 2009 15:41:37 +0200 Subject: sched: Turn off child_runs_first Set child_runs_first default to off. It hurts 'optimal' make -j workloads as make jobs get preempted by child tasks, reducing parallelism. Note, this patch might make existing races in user applications more prominent than before - so breakages might be bisected to this commit. Child-runs-first is broken on SMP to begin with, and we already had it off briefly in v2.6.23 so most of the offenders ought to be fixed. Would be nice not to revert this commit but fix those apps finally ... Signed-off-by: Mike Galbraith Acked-by: Peter Zijlstra LKML-Reference: <1252486344.28645.18.camel@marge.simson.net> [ made the sysctl independent of CONFIG_SCHED_DEBUG, in case people want to work around broken apps. ] Signed-off-by: Ingo Molnar --- include/linux/sched.h | 2 +- kernel/sched_fair.c | 4 ++-- kernel/sysctl.c | 16 ++++++++-------- 3 files changed, 11 insertions(+), 11 deletions(-) (limited to 'kernel/sysctl.c') diff --git a/include/linux/sched.h b/include/linux/sched.h index 3b7f43e3b736..3a50e8222498 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1820,8 +1820,8 @@ extern unsigned int sysctl_sched_min_granularity; extern unsigned int sysctl_sched_wakeup_granularity; extern unsigned int sysctl_sched_shares_ratelimit; extern unsigned int sysctl_sched_shares_thresh; -#ifdef CONFIG_SCHED_DEBUG extern unsigned int sysctl_sched_child_runs_first; +#ifdef CONFIG_SCHED_DEBUG extern unsigned int sysctl_sched_features; extern unsigned int sysctl_sched_migration_cost; extern unsigned int sysctl_sched_nr_migrate; diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index e386e5dfcdae..af325a382b1b 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -48,10 +48,10 @@ unsigned int sysctl_sched_min_granularity = 4000000ULL; static unsigned int sched_nr_latency = 5; /* - * After fork, child runs first. (default) If set to 0 then + * After fork, child runs first. If set to 0 (default) then * parent will (try to) run first. */ -const_debug unsigned int sysctl_sched_child_runs_first = 1; +unsigned int sysctl_sched_child_runs_first __read_mostly; /* * sys_sched_yield() compat mode diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 6c9836ef4b47..25d6bf3383be 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -246,6 +246,14 @@ static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ #endif static struct ctl_table kern_table[] = { + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_child_runs_first", + .data = &sysctl_sched_child_runs_first, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, #ifdef CONFIG_SCHED_DEBUG { .ctl_name = CTL_UNNUMBERED, @@ -298,14 +306,6 @@ static struct ctl_table kern_table[] = { .strategy = &sysctl_intvec, .extra1 = &zero, }, - { - .ctl_name = CTL_UNNUMBERED, - .procname = "sched_child_runs_first", - .data = &sysctl_sched_child_runs_first, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = &proc_dointvec, - }, { .ctl_name = CTL_UNNUMBERED, .procname = "sched_features", -- cgit v1.2.3