mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-05 18:14:07 +08:00
sched/cpuacct: Remove redundant NULL checks in cpuacct_charge()
This is a micro optimization for the hot path. - We don't need to check if @ca is NULL in parent_ca(). - We don't need to check if @ca is NULL in the beginning of the for loop. Signed-off-by: Li Zefan <lizefan@huawei.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/515536A9.5000700@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
parent
1966aaf7d5
commit
543bc0e76e
@ -210,9 +210,13 @@ void cpuacct_charge(struct task_struct *tsk, u64 cputime)
|
||||
|
||||
ca = task_ca(tsk);
|
||||
|
||||
for (; ca; ca = parent_ca(ca)) {
|
||||
while (true) {
|
||||
u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
|
||||
*cpuusage += cputime;
|
||||
|
||||
ca = parent_ca(ca);
|
||||
if (!ca)
|
||||
break;
|
||||
}
|
||||
|
||||
rcu_read_unlock();
|
||||
|
@ -36,7 +36,7 @@ static inline struct cpuacct *task_ca(struct task_struct *tsk)
|
||||
|
||||
static inline struct cpuacct *parent_ca(struct cpuacct *ca)
|
||||
{
|
||||
if (!ca || !ca->css.cgroup->parent)
|
||||
if (!ca->css.cgroup->parent)
|
||||
return NULL;
|
||||
return cgroup_ca(ca->css.cgroup->parent);
|
||||
}
|
||||
|
Loading…
Reference in New Issue
Block a user