diff options
| author | Rik van Riel <riel@redhat.com> | 2016-07-13 16:50:02 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-07-14 10:42:34 +0200 |
| commit | b58c35840521bb02b150e1d0d34ca9197f8b7145 (patch) | |
| tree | a1641840e235a1035e7ad8c4276a77d25552ba4e /include/linux/vtime.h | |
| parent | 57430218317e5b280a80582a139b26029c25de6c (diff) | |
sched/cputime: Replace VTIME_GEN irq time code with IRQ_TIME_ACCOUNTING code
The CONFIG_VIRT_CPU_ACCOUNTING_GEN irq time tracking code does not
appear to currently work right.
On CPUs without nohz_full=, only tick based irq time sampling is
done, which breaks down when dealing with a nohz_idle CPU.
On firewalls and similar systems, no ticks may happen on a CPU for a
while, and the irq time spent may never get accounted properly. This
can cause issues with capacity planning and power saving, which use
the CPU statistics as inputs in decision making.
Remove the VTIME_GEN vtime irq time code, and replace it with the
IRQ_TIME_ACCOUNTING code, when selected as a config option by the user.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/vtime.h')
| -rw-r--r-- | include/linux/vtime.h | 32 |
1 files changed, 14 insertions, 18 deletions
diff --git a/include/linux/vtime.h b/include/linux/vtime.h index fa2196990f84..d1977d84ebdf 100644 --- a/include/linux/vtime.h +++ b/include/linux/vtime.h @@ -14,6 +14,18 @@ struct task_struct; */ #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE static inline bool vtime_accounting_cpu_enabled(void) { return true; } + +#ifdef __ARCH_HAS_VTIME_ACCOUNT +extern void vtime_account_irq_enter(struct task_struct *tsk); +#else +extern void vtime_common_account_irq_enter(struct task_struct *tsk); +static inline void vtime_account_irq_enter(struct task_struct *tsk) +{ + if (vtime_accounting_cpu_enabled()) + vtime_common_account_irq_enter(tsk); +} +#endif /* __ARCH_HAS_VTIME_ACCOUNT */ + #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN @@ -64,17 +76,6 @@ extern void vtime_account_system(struct task_struct *tsk); extern void vtime_account_idle(struct task_struct *tsk); extern void vtime_account_user(struct task_struct *tsk); -#ifdef __ARCH_HAS_VTIME_ACCOUNT -extern void vtime_account_irq_enter(struct task_struct *tsk); -#else -extern void vtime_common_account_irq_enter(struct task_struct *tsk); -static inline void vtime_account_irq_enter(struct task_struct *tsk) -{ - if (vtime_accounting_cpu_enabled()) - vtime_common_account_irq_enter(tsk); -} -#endif /* __ARCH_HAS_VTIME_ACCOUNT */ - #else /* !CONFIG_VIRT_CPU_ACCOUNTING */ static inline void vtime_task_switch(struct task_struct *prev) { } @@ -85,13 +86,8 @@ static inline void vtime_account_irq_enter(struct task_struct *tsk) { } #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN extern void arch_vtime_task_switch(struct task_struct *tsk); -extern void vtime_gen_account_irq_exit(struct task_struct *tsk); - -static inline void vtime_account_irq_exit(struct task_struct *tsk) -{ - if (vtime_accounting_cpu_enabled()) - vtime_gen_account_irq_exit(tsk); -} +static inline void vtime_account_irq_enter(struct task_struct *tsk) { } +static inline void vtime_account_irq_exit(struct task_struct *tsk) { } extern void vtime_user_enter(struct task_struct *tsk); |