diff options
| author | Syed Rameez Mustafa <rameezmustafa@codeaurora.org> | 2016-12-13 16:50:58 -0800 |
|---|---|---|
| committer | Syed Rameez Mustafa <rameezmustafa@codeaurora.org> | 2016-12-14 14:56:27 -0800 |
| commit | 3366a508ffb6b0698dd309d1ca19a66522b886b1 (patch) | |
| tree | 328b6ec2af333d45c0681febcdde33f774816999 /kernel/sched | |
| parent | a80e267a8c0d61790c3d1d5f7181ebd1be39c438 (diff) | |
Revert "sched/cputime: Fix steal time accounting vs. CPU hotplug"
This reverts commit 2a8225ef46968444fb1c4c632ec28e4cc2be633f
("sched/cputime: Fix steal time accounting vs. CPU hotplug").
The commit introduces a bug in scheduler book-keeping whereby if a CPU
is hotplugged out for a small duration of time, subsequent time spent
executing tasks gets mis-attributed to interrupts. This in turn results
in unfair scheduling whereby a task can keep executing for a very long
time without any update to it's vruntime. This revert has no side
effects for msm based systems.
Change-Id: Ibb506824c4223551bceb449594ac99f9dfd8064b
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/core.c | 1 | ||||
| -rw-r--r-- | kernel/sched/sched.h | 13 |
2 files changed, 0 insertions, 14 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index ee708909dc17..307f430e5bd5 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6066,7 +6066,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) set_window_start(rq); raw_spin_unlock_irqrestore(&rq->lock, flags); rq->calc_load_update = calc_load_update; - account_reset_rq(rq); break; case CPU_ONLINE: diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index f569c6fe3cbb..6f8123ca878b 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2534,16 +2534,3 @@ static inline u64 irq_time_read(int cpu) } #endif /* CONFIG_64BIT */ #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ - -static inline void account_reset_rq(struct rq *rq) -{ -#ifdef CONFIG_IRQ_TIME_ACCOUNTING - rq->prev_irq_time = 0; -#endif -#ifdef CONFIG_PARAVIRT - rq->prev_steal_time = 0; -#endif -#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING - rq->prev_steal_time_rq = 0; -#endif -} |