From: Ingo Molnar Date: Sun, 16 Mar 2008 19:56:26 +0000 (+0100) Subject: sched: clean up wakeup balancing, rename variables X-Git-Tag: v2.6.25-rc7~102^2~6 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ac192d3921a14e2c9080799e16959b4bd56f49d6;p=linux-2.6 sched: clean up wakeup balancing, rename variables rename 'cpu' to 'prev_cpu'. No code changed: kernel/sched.o: text data bss dec hex filename 42521 2858 232 45611 b22b sched.o.before 42521 2858 232 45611 b22b sched.o.after md5: 09b31c44e9aff8666f72773dc433e2df sched.o.before.asm 09b31c44e9aff8666f72773dc433e2df sched.o.after.asm Signed-off-by: Ingo Molnar --- diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 70679b2666..2d2be02b8e 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -983,7 +983,7 @@ static inline int wake_idle(int cpu, struct task_struct *p) static int wake_affine(struct rq *rq, struct sched_domain *this_sd, struct task_struct *p, - int cpu, int this_cpu, int sync, int idx, + int prev_cpu, int this_cpu, int sync, int idx, unsigned long load, unsigned long this_load, unsigned int imbalance) { @@ -1010,7 +1010,7 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct task_struct *p, if (sync) tl -= current->se.load.weight; - if ((tl <= load && tl + target_load(cpu, idx) <= tl_per_task) || + if ((tl <= load && tl + target_load(prev_cpu, idx) <= tl_per_task) || 100*(tl + p->se.load.weight) <= imbalance*load) { /* * This domain has SD_WAKE_AFFINE and @@ -1028,22 +1028,26 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct task_struct *p, static int select_task_rq_fair(struct task_struct *p, int sync) { struct sched_domain *sd, *this_sd = NULL; + int prev_cpu, this_cpu, new_cpu; unsigned long load, this_load; - int cpu, this_cpu, new_cpu; unsigned int imbalance; struct rq *rq; int idx; - cpu = task_cpu(p); - rq = task_rq(p); - this_cpu = smp_processor_id(); - new_cpu = cpu; + prev_cpu = task_cpu(p); + rq = task_rq(p); + this_cpu = smp_processor_id(); + new_cpu = prev_cpu; - if (cpu == this_cpu) + if (prev_cpu == this_cpu) goto out_set_cpu; + /* + * 'this_sd' is the first domain that both + * this_cpu and prev_cpu are present in: + */ for_each_domain(this_cpu, sd) { - if (cpu_isset(cpu, sd->span)) { + if (cpu_isset(prev_cpu, sd->span)) { this_sd = sd; break; } @@ -1062,12 +1066,12 @@ static int select_task_rq_fair(struct task_struct *p, int sync) imbalance = 100 + (this_sd->imbalance_pct - 100) / 2; - load = source_load(cpu, idx); + load = source_load(prev_cpu, idx); this_load = target_load(this_cpu, idx); new_cpu = this_cpu; /* Wake to this CPU if we can */ - if (wake_affine(rq, this_sd, p, cpu, this_cpu, sync, idx, + if (wake_affine(rq, this_sd, p, prev_cpu, this_cpu, sync, idx, load, this_load, imbalance)) goto out_set_cpu; @@ -1084,7 +1088,11 @@ static int select_task_rq_fair(struct task_struct *p, int sync) } out_keep_cpu: - new_cpu = cpu; /* Could not wake to this_cpu. Wake to cpu instead */ + /* + * Could not wake to this_cpu. + * Wake to the previous cpu instead: + */ + new_cpu = prev_cpu; out_set_cpu: return wake_idle(new_cpu, p); }