From: Peter Zijlstra <peterz@infradead.org>
To: mingo@kernel.org, lvenanci@redhat.com
Cc: lwang@redhat.com, riel@redhat.com, efault@gmx.de,
tglx@linutronix.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 00/14] sched/topology fixes
Date: Fri, 28 Apr 2017 15:53:39 +0200 [thread overview]
Message-ID: <20170428135339.diwcabxhcpu4b5fw@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20170428131958.893188882@infradead.org>
On Fri, Apr 28, 2017 at 03:19:58PM +0200, Peter Zijlstra wrote:
> Hi,
>
> These patches are based upon the hard work of Lauro. He put in the time and
> effort to understand and debug the code.
>
> So while I didn't take many of his actual patches; I want to thank him for
> doing the work. Hopefully the "Debugged-by:" tag conveys some of that.
>
> In any case, please have a look. I think these should about cover things.
>
> Rik, Lauro, could you guys in particular look at the final patch that adds a
> few comments. I attempted to document the intent and understanding there. But
> given I've been staring at this stuff too long I could've missed the obvious.
>
> Comments and or suggestions welcome.
>
Also, the following occurred to me:
sg_span & sg_mask == sg_mask
Therefore, we don't need to do the whole "sg_span &" business.
Hmm?
---
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7996,7 +7996,7 @@ static int active_load_balance_cpu_stop(
static int should_we_balance(struct lb_env *env)
{
struct sched_group *sg = env->sd->groups;
- struct cpumask *sg_cpus, *sg_mask;
+ struct cpumask *sg_mask;
int cpu, balance_cpu = -1;
/*
@@ -8006,11 +8006,10 @@ static int should_we_balance(struct lb_e
if (env->idle == CPU_NEWLY_IDLE)
return 1;
- sg_cpus = sched_group_cpus(sg);
sg_mask = sched_group_mask(sg);
/* Try to find first idle cpu */
- for_each_cpu_and(cpu, sg_cpus, env->cpus) {
- if (!cpumask_test_cpu(cpu, sg_mask) || !idle_cpu(cpu))
+ for_each_cpu_and(cpu, sg_mask, env->cpus) {
+ if (!idle_cpu(cpu))
continue;
balance_cpu = cpu;
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -85,7 +85,8 @@ static int sched_domain_debug_one(struct
group->sgc->id,
cpumask_pr_args(sched_group_cpus(group)));
- if ((sd->flags & SD_OVERLAP) && !cpumask_full(sched_group_mask(group))) {
+ if ((sd->flags & SD_OVERLAP) &&
+ !cpumask_equal(sched_group_mask(group), sched_group_cpus(group))) {
printk(KERN_CONT " mask=%*pbl",
cpumask_pr_args(sched_group_mask(group)));
}
@@ -505,7 +506,7 @@ enum s_alloc {
*/
int group_balance_cpu(struct sched_group *sg)
{
- return cpumask_first_and(sched_group_cpus(sg), sched_group_mask(sg));
+ return cpumask_first(sched_group_mask(sg));
}
@@ -856,7 +857,7 @@ build_sched_groups(struct sched_domain *
continue;
group = get_group(i, sdd, &sg);
- cpumask_setall(sched_group_mask(sg));
+ cpumask_copy(sched_group_mask(sg), sched_group_cpus(sg));
for_each_cpu(j, span) {
if (get_group(j, sdd, NULL) != group)
next prev parent reply other threads:[~2017-04-28 13:53 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-28 13:19 [PATCH 00/14] sched/topology fixes Peter Zijlstra
2017-04-28 13:19 ` [PATCH 01/14] sched/topology: Refactor function build_overlap_sched_groups() Peter Zijlstra
2017-04-28 13:20 ` [PATCH 02/14] sched,cpumask: Export for_each_cpu_wrap() Peter Zijlstra
2017-05-01 19:56 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 03/14] sched/topology: Fix building of overlapping sched-groups Peter Zijlstra
2017-05-01 20:08 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 04/14] sched/topology: Simplify build_overlap_sched_groups() Peter Zijlstra
2017-05-01 21:04 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 05/14] sched/topology,debug: Print the group mask Peter Zijlstra
2017-05-01 21:13 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 06/14] sched/topology,debug: Verify the first group matches the child domain Peter Zijlstra
2017-05-01 21:13 ` Rik van Riel
2017-05-02 14:52 ` Peter Zijlstra
2017-05-03 15:00 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 07/14] sched/topology: Optimize build_group_mask() Peter Zijlstra
2017-05-02 0:57 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 08/14] sched/topology: Move comment about asymmetric node setups Peter Zijlstra
2017-05-02 1:08 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 09/14] sched/topology: Remove FORCE_SD_OVERLAP Peter Zijlstra
2017-05-02 1:09 ` Rik van Riel
2017-04-28 13:20 ` [PATCH 10/14] sched/topology: Fix overlapping sched_group_mask Peter Zijlstra
2017-04-28 13:20 ` [PATCH 11/14] sched/topology: Small cleanup Peter Zijlstra
2017-04-28 13:20 ` [PATCH 12/14] sched/topology,debug: Add sched_group_capacity debugging Peter Zijlstra
2017-04-28 13:20 ` [PATCH 13/14] sched/topology: Fix overlapping sched_group_capacity Peter Zijlstra
2017-04-28 13:20 ` [PATCH 14/14] sched/topology: Add a few comments Peter Zijlstra
2017-05-01 8:35 ` Peter Zijlstra
2017-04-28 13:53 ` Peter Zijlstra [this message]
2017-04-28 23:30 ` [PATCH 00/14] sched/topology fixes Lauro Venancio
2017-05-01 8:57 ` Peter Zijlstra
2017-05-02 14:43 ` Peter Zijlstra
2017-05-02 14:54 ` Lauro Venancio
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