From bf5015a50f1fdb248b48405b67cae24dc02605d6 Mon Sep 17 00:00:00 2001 From: Juri Lelli Date: Thu, 24 May 2018 17:29:36 +0200 Subject: [PATCH] sched/topology: Clarify root domain(s) debug string When scheduler debug is enabled, building scheduling domains outputs information about how the domains are laid out and to which root domain each CPU (or sets of CPUs) belongs, e.g.: CPU0 attaching sched-domain(s): domain-0: span=0-5 level=MC groups: 0:{ span=0 }, 1:{ span=1 }, 2:{ span=2 }, 3:{ span=3 }, 4:{ span=4 }, 5:{ span=5 } CPU1 attaching sched-domain(s): domain-0: span=0-5 level=MC groups: 1:{ span=1 }, 2:{ span=2 }, 3:{ span=3 }, 4:{ span=4 }, 5:{ span=5 }, 0:{ span=0 } [...] span: 0-5 (max cpu_capacity = 1024) The fact that latest line refers to CPUs 0-5 root domain doesn't however look immediately obvious to me: one might wonder why span 0-5 is reported "again". Make it more clear by adding "root domain" to it, as to end with the following: CPU0 attaching sched-domain(s): domain-0: span=0-5 level=MC groups: 0:{ span=0 }, 1:{ span=1 }, 2:{ span=2 }, 3:{ span=3 }, 4:{ span=4 }, 5:{ span=5 } CPU1 attaching sched-domain(s): domain-0: span=0-5 level=MC groups: 1:{ span=1 }, 2:{ span=2 }, 3:{ span=3 }, 4:{ span=4 }, 5:{ span=5 }, 0:{ span=0 } [...] root domain span: 0-5 (max cpu_capacity = 1024) Signed-off-by: Juri Lelli Signed-off-by: Peter Zijlstra (Intel) Cc: Dietmar Eggemann Cc: Linus Torvalds Cc: Patrick Bellasi Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20180524152936.17611-1-juri.lelli@redhat.com Signed-off-by: Ingo Molnar --- kernel/sched/topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 64cc564..61a1125 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -1708,7 +1708,7 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att rcu_read_unlock(); if (rq && sched_debug_enabled) { - pr_info("span: %*pbl (max cpu_capacity = %lu)\n", + pr_info("root domain span: %*pbl (max cpu_capacity = %lu)\n", cpumask_pr_args(cpu_map), rq->rd->max_cpu_capacity); } -- 2.7.4