[PATCH] sched/fair: Remove the redundant check in numa_id_core
the numa_idle_core() function have a little redundant. then this patch move the "idle_core >= 0" check in numa_idle_core() to its caller in update_numa_stats() and then remove the redundant check in !static_branch_likely(&sched_smt_present) check in numa_idle_core. Signed-off-by: Tian Tao <tiantao6@hisilicon.com> --- kernel/sched/fair.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index afb895a3..bae974a 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1569,8 +1569,7 @@ numa_type numa_classify(unsigned int imbalance_pct, static inline bool test_idle_cores(int cpu, bool def); static inline int numa_idle_core(int idle_core, int cpu) { - if (!static_branch_likely(&sched_smt_present) || - idle_core >= 0 || !test_idle_cores(cpu, false)) + if (!test_idle_cores(cpu, false)) return idle_core; /* @@ -1622,7 +1621,8 @@ static void update_numa_stats(struct task_numa_env *env, if (ns->idle_cpu == -1) ns->idle_cpu = cpu; - idle_core = numa_idle_core(idle_core, cpu); + if (idle_core >= 0) + idle_core = numa_idle_core(idle_core, cpu); } } rcu_read_unlock(); -- 2.7.4
-----Original Message----- From: tiantao (H) Sent: Tuesday, March 23, 2021 3:19 PM To: Song Bao Hua (Barry Song) <song.bao.hua@hisilicon.com> Cc: linuxarm@openeuler.org; tiantao (H) <tiantao6@hisilicon.com> Subject: [PATCH] sched/fair: Remove the redundant check in numa_id_core
the numa_idle_core() function have a little redundant. then this patch move the "idle_core >= 0" check in numa_idle_core() to its caller in update_numa_stats() and then remove the redundant check in !static_branch_likely(&sched_smt_present) check in numa_idle_core.
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Hi Tao, Thanks! Looks correct to me. Let's send it to maillist to get feedback, perhaps Mel Gorman will have some comments, like completely removing the function.
---
Better to put some words below "---" to say this patch is addressing the comment of Mel Gorman in the below thread so that people can understand the background better: https://lore.kernel.org/lkml/20210322101556.GK15768@suse.de/
kernel/sched/fair.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index afb895a3..bae974a 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1569,8 +1569,7 @@ numa_type numa_classify(unsigned int imbalance_pct, static inline bool test_idle_cores(int cpu, bool def); static inline int numa_idle_core(int idle_core, int cpu) { - if (!static_branch_likely(&sched_smt_present) || - idle_core >= 0 || !test_idle_cores(cpu, false)) + if (!test_idle_cores(cpu, false)) return idle_core;
/* @@ -1622,7 +1621,8 @@ static void update_numa_stats(struct task_numa_env *env, if (ns->idle_cpu == -1) ns->idle_cpu = cpu;
- idle_core = numa_idle_core(idle_core, cpu); + if (idle_core >= 0) + idle_core = numa_idle_core(idle_core, cpu); } } rcu_read_unlock(); -- 2.7.4
Thanks Barry
participants (2)
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Song Bao Hua (Barry Song) -
Tian Tao