diff --git a/kernel.spec b/kernel.spec index 8c8d920..f14fb24 100644 --- a/kernel.spec +++ b/kernel.spec @@ -748,6 +748,7 @@ Patch12570: sched-10-change-nohz-idle-load-balancing-logic-to-push-model.patch Patch12575: sched-15-update-rq-clock-for-nohz-balanced-cpus.patch Patch12580: sched-20-fix-rq-clock-synchronization-when-migrating-tasks.patch Patch12585: sched-25-move-sched_avg_update-to-update_cpu_load.patch +Patch12590: sched-30-sched-fix-nohz-balance-kick.patch Patch13600: btusb-macbookpro-6-2.patch Patch13601: btusb-macbookpro-7-1.patch @@ -1388,6 +1389,7 @@ ApplyPatch sched-10-change-nohz-idle-load-balancing-logic-to-push-model.patch ApplyPatch sched-15-update-rq-clock-for-nohz-balanced-cpus.patch ApplyPatch sched-20-fix-rq-clock-synchronization-when-migrating-tasks.patch ApplyPatch sched-25-move-sched_avg_update-to-update_cpu_load.patch +ApplyPatch sched-30-sched-fix-nohz-balance-kick.patch ApplyPatch btusb-macbookpro-7-1.patch ApplyPatch btusb-macbookpro-6-2.patch @@ -1978,6 +1980,9 @@ fi # and build. %changelog +* Wed Sep 22 2010 Chuck Ebbert +- Fix possible lockup with new scheduler idle balance code. + * Tue Sep 21 2010 Kyle McMartin - Add new btusb ids for MacBookPro from wwoods@. diff --git a/sched-30-sched-fix-nohz-balance-kick.patch b/sched-30-sched-fix-nohz-balance-kick.patch new file mode 100644 index 0000000..debad52 --- /dev/null +++ b/sched-30-sched-fix-nohz-balance-kick.patch @@ -0,0 +1,39 @@ +From: Suresh Siddha +Date: Mon, 13 Sep 2010 18:02:21 +0000 (-0700) +Subject: sched: Fix nohz balance kick +X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=f6c3f1686e7ec1dd8725a9a3dcb857dfd0c7a5bf + +sched: Fix nohz balance kick + +There's a situation where the nohz balancer will try to wake itself: + +cpu-x is idle which is also ilb_cpu +got a scheduler tick during idle +and the nohz_kick_needed() in trigger_load_balance() checks for +rq_x->nr_running which might not be zero (because of someone waking a +task on this rq etc) and this leads to the situation of the cpu-x +sending a kick to itself. + +And this can cause a lockup. + +Avoid this by not marking ourself eligible for kicking. + +Signed-off-by: Suresh Siddha +Signed-off-by: Peter Zijlstra +LKML-Reference: <1284400941.2684.19.camel@sbsiddha-MOBL3.sc.intel.com> +Signed-off-by: Ingo Molnar +--- + +diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c +index a171138..db3f674 100644 +--- a/kernel/sched_fair.c ++++ b/kernel/sched_fair.c +@@ -3630,7 +3630,7 @@ static inline int nohz_kick_needed(struct rq *rq, int cpu) + if (time_before(now, nohz.next_balance)) + return 0; + +- if (!rq->nr_running) ++ if (rq->idle_at_tick) + return 0; + + first_pick_cpu = atomic_read(&nohz.first_pick_cpu);