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author | Wanpeng Li <wanpeng.li@hotmail.com> | 2016-06-13 12:32:46 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-06-14 11:13:16 +0200 |
commit | 807e5b80687c06715d62df51a5473b231e3e8b15 (patch) | |
tree | ee8b826e1ec1b9f3eee395a4fc1af6d01032dbf8 /kernel/sched | |
parent | sched/cputime: Fix prev steal time accouting during CPU hotplug (diff) | |
download | linux-807e5b80687c06715d62df51a5473b231e3e8b15.tar.xz linux-807e5b80687c06715d62df51a5473b231e3e8b15.zip |
sched/cputime: Add steal time support to full dynticks CPU time accounting
This patch adds guest steal-time support to full dynticks CPU
time accounting. After the following commit:
ff9a9b4c4334 ("sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity")
... time sampling became jiffy based, even if we do the sampling from the
context tracking code, so steal_account_process_tick() can be reused
to account how many 'ticks' are stolen-time, after the last accumulation.
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1465813966-3116-4-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched')
-rw-r--r-- | kernel/sched/cputime.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index 75f98c5498d5..3d60e5d76fdb 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -257,7 +257,7 @@ void account_idle_time(cputime_t cputime) cpustat[CPUTIME_IDLE] += (__force u64) cputime; } -static __always_inline bool steal_account_process_tick(void) +static __always_inline unsigned long steal_account_process_tick(unsigned long max_jiffies) { #ifdef CONFIG_PARAVIRT if (static_key_false(¶virt_steal_enabled)) { @@ -272,14 +272,14 @@ static __always_inline bool steal_account_process_tick(void) * time in jiffies. Lets cast the result to jiffies * granularity and account the rest on the next rounds. */ - steal_jiffies = nsecs_to_jiffies(steal); + steal_jiffies = min(nsecs_to_jiffies(steal), max_jiffies); this_rq()->prev_steal_time += jiffies_to_nsecs(steal_jiffies); account_steal_time(jiffies_to_cputime(steal_jiffies)); return steal_jiffies; } #endif - return false; + return 0; } /* @@ -346,7 +346,7 @@ static void irqtime_account_process_tick(struct task_struct *p, int user_tick, u64 cputime = (__force u64) cputime_one_jiffy; u64 *cpustat = kcpustat_this_cpu->cpustat; - if (steal_account_process_tick()) + if (steal_account_process_tick(ULONG_MAX)) return; cputime *= ticks; @@ -477,7 +477,7 @@ void account_process_tick(struct task_struct *p, int user_tick) return; } - if (steal_account_process_tick()) + if (steal_account_process_tick(ULONG_MAX)) return; if (user_tick) @@ -681,12 +681,14 @@ static cputime_t vtime_delta(struct task_struct *tsk) static cputime_t get_vtime_delta(struct task_struct *tsk) { unsigned long now = READ_ONCE(jiffies); - unsigned long delta = now - tsk->vtime_snap; + unsigned long delta_jiffies, steal_jiffies; + delta_jiffies = now - tsk->vtime_snap; + steal_jiffies = steal_account_process_tick(delta_jiffies); WARN_ON_ONCE(tsk->vtime_snap_whence == VTIME_INACTIVE); tsk->vtime_snap = now; - return jiffies_to_cputime(delta); + return jiffies_to_cputime(delta_jiffies - steal_jiffies); } static void __vtime_account_system(struct task_struct *tsk) |