diff options
author | Peter Zijlstra <peterz@infradead.org> | 2008-11-24 16:06:57 (GMT) |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2009-01-07 17:52:44 (GMT) |
commit | 490dea45d00f01847ebebd007685d564aaf2cd98 (patch) | |
tree | a1f559fd497b10c21479b378ffb262d517cb627b /kernel/sched_stats.h | |
parent | ede6f5aea054d3fb67c78857f7abdee602302043 (diff) | |
download | linux-fsl-qoriq-490dea45d00f01847ebebd007685d564aaf2cd98.tar.xz |
itimers: remove the per-cpu-ish-ness
Either we bounce once cacheline per cpu per tick, yielding n^2 bounces
or we just bounce a single..
Also, using per-cpu allocations for the thread-groups complicates the
per-cpu allocator in that its currently aimed to be a fixed sized
allocator and the only possible extention to that would be vmap based,
which is seriously constrained on 32 bit archs.
So making the per-cpu memory requirement depend on the number of
processes is an issue.
Lastly, it didn't deal with cpu-hotplug, although admittedly that might
be fixable.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_stats.h')
-rw-r--r-- | kernel/sched_stats.h | 33 |
1 files changed, 15 insertions, 18 deletions
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h index f2773b5..8ab0cef 100644 --- a/kernel/sched_stats.h +++ b/kernel/sched_stats.h @@ -296,6 +296,7 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next) static inline void account_group_user_time(struct task_struct *tsk, cputime_t cputime) { + struct task_cputime *times; struct signal_struct *sig; /* tsk == current, ensure it is safe to use ->signal */ @@ -303,13 +304,11 @@ static inline void account_group_user_time(struct task_struct *tsk, return; sig = tsk->signal; - if (sig->cputime.totals) { - struct task_cputime *times; + times = &sig->cputime.totals; - times = per_cpu_ptr(sig->cputime.totals, get_cpu()); - times->utime = cputime_add(times->utime, cputime); - put_cpu_no_resched(); - } + spin_lock(×->lock); + times->utime = cputime_add(times->utime, cputime); + spin_unlock(×->lock); } /** @@ -325,6 +324,7 @@ static inline void account_group_user_time(struct task_struct *tsk, static inline void account_group_system_time(struct task_struct *tsk, cputime_t cputime) { + struct task_cputime *times; struct signal_struct *sig; /* tsk == current, ensure it is safe to use ->signal */ @@ -332,13 +332,11 @@ static inline void account_group_system_time(struct task_struct *tsk, return; sig = tsk->signal; - if (sig->cputime.totals) { - struct task_cputime *times; + times = &sig->cputime.totals; - times = per_cpu_ptr(sig->cputime.totals, get_cpu()); - times->stime = cputime_add(times->stime, cputime); - put_cpu_no_resched(); - } + spin_lock(×->lock); + times->stime = cputime_add(times->stime, cputime); + spin_unlock(×->lock); } /** @@ -354,6 +352,7 @@ static inline void account_group_system_time(struct task_struct *tsk, static inline void account_group_exec_runtime(struct task_struct *tsk, unsigned long long ns) { + struct task_cputime *times; struct signal_struct *sig; sig = tsk->signal; @@ -362,11 +361,9 @@ static inline void account_group_exec_runtime(struct task_struct *tsk, if (unlikely(!sig)) return; - if (sig->cputime.totals) { - struct task_cputime *times; + times = &sig->cputime.totals; - times = per_cpu_ptr(sig->cputime.totals, get_cpu()); - times->sum_exec_runtime += ns; - put_cpu_no_resched(); - } + spin_lock(×->lock); + times->sum_exec_runtime += ns; + spin_unlock(×->lock); } |