cpuset: Cleanup cpuset_cpus_allowed_fallback() use in select_fallback_rq()

select_fallback_rq() only needs to recheck for an allowed CPU if the
affinity mask of the task has changed since the last check.

Return a 'bool' from cpuset_cpus_allowed_fallback() to indicate whether
the affinity mask was updated, and use this to elide the allowed check
when the mask has been left alone.

No functional change.

Suggested-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lore.kernel.org/r/20210730112443.23245-5-will@kernel.org
This commit is contained in:
Will Deacon
2021-07-30 12:24:31 +01:00
committed by Peter Zijlstra
parent 431c69fac0
commit 97c0054dbe
3 changed files with 12 additions and 6 deletions

View File

@@ -59,7 +59,7 @@ extern void cpuset_wait_for_hotplug(void);
extern void cpuset_read_lock(void);
extern void cpuset_read_unlock(void);
extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
extern void cpuset_cpus_allowed_fallback(struct task_struct *p);
extern bool cpuset_cpus_allowed_fallback(struct task_struct *p);
extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
#define cpuset_current_mems_allowed (current->mems_allowed)
void cpuset_init_current_mems_allowed(void);
@@ -188,8 +188,9 @@ static inline void cpuset_cpus_allowed(struct task_struct *p,
cpumask_copy(mask, task_cpu_possible_mask(p));
}
static inline void cpuset_cpus_allowed_fallback(struct task_struct *p)
static inline bool cpuset_cpus_allowed_fallback(struct task_struct *p)
{
return false;
}
static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)