From 22da956953f371c1ee7a578c31ed8c5702cb52b1 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 4 Jun 2013 15:41:15 +0530 Subject: [PATCH] sched: Optimize build_sched_domains() for saving first SD node for a cpu We are saving first scheduling domain for a cpu in build_sched_domains() by iterating over the nested sd->child list. We don't actually need to do it this way. tl will be equal to sched_domain_topology for the first iteration and so we can set *per_cpu_ptr(d.sd, i) based on that. So, save pointer to first SD while running the iteration loop over tl's. Signed-off-by: Viresh Kumar Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/fc473527cbc4dfa0b8eeef2a59db74684eb59a83.1370436120.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar --- kernel/sched/core.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 342e744..137dcc0 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5985,16 +5985,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, sd = NULL; for (tl = sched_domain_topology; tl->init; tl++) { sd = build_sched_domain(tl, cpu_map, attr, sd, i); + if (tl == sched_domain_topology) + *per_cpu_ptr(d.sd, i) = sd; if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP)) sd->flags |= SD_OVERLAP; if (cpumask_equal(cpu_map, sched_domain_span(sd))) break; } - - while (sd->child) - sd = sd->child; - - *per_cpu_ptr(d.sd, i) = sd; } /* Build the groups for the domains */ -- 2.7.4