[PATCH] sched: core: Optimize the structure of 'tg_cfs_schedulable_down' function

Li kunyu posted 1 patch 1 year, 1 month ago
kernel/sched/core.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)
[PATCH] sched: core: Optimize the structure of 'tg_cfs_schedulable_down' function
Posted by Li kunyu 1 year, 1 month ago
Optimize if branches and define  in the branch statement
block parent_quota variable.

Signed-off-by: Li kunyu <kunyu@nfschina.com>
---
 kernel/sched/core.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 488655f2319f..7e8535d2e36d 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -10915,15 +10915,12 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
 {
 	struct cfs_schedulable_data *d = data;
 	struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
-	s64 quota = 0, parent_quota = -1;
+	s64 quota = RUNTIME_INF;
 
-	if (!tg->parent) {
-		quota = RUNTIME_INF;
-	} else {
+	if (tg->parent) {
 		struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth;
-
+		s64 parent_quota = parent_b->hierarchical_quota;
 		quota = normalize_cfs_quota(tg, d);
-		parent_quota = parent_b->hierarchical_quota;
 
 		/*
 		 * Ensure max(child_quota) <= parent_quota.  On cgroup2,
-- 
2.18.2

Re: [PATCH] sched: core: Optimize the structure of 'tg_cfs_schedulable_down' function
Posted by Benjamin Segall 1 year, 1 month ago
Li kunyu <kunyu@nfschina.com> writes:

> Optimize if branches and define  in the branch statement
> block parent_quota variable.

It's not an optimization; it is arguably a slight style improvement.

>
> Signed-off-by: Li kunyu <kunyu@nfschina.com>
> ---
>  kernel/sched/core.c | 9 +++------
>  1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 488655f2319f..7e8535d2e36d 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -10915,15 +10915,12 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
>  {
>  	struct cfs_schedulable_data *d = data;
>  	struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
> -	s64 quota = 0, parent_quota = -1;
> +	s64 quota = RUNTIME_INF;
>  
> -	if (!tg->parent) {
> -		quota = RUNTIME_INF;
> -	} else {
> +	if (tg->parent) {
>  		struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth;
> -
> +		s64 parent_quota = parent_b->hierarchical_quota;
>  		quota = normalize_cfs_quota(tg, d);
> -		parent_quota = parent_b->hierarchical_quota;
>  
>  		/*
>  		 * Ensure max(child_quota) <= parent_quota.  On cgroup2,