From: Peter Zijlstra <peterz@infradead.org>
To: Xunlei Pang <xlpang@redhat.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH] sched/core: Clear the root_domain cpumasks in init_rootdomain()
Date: Thu, 3 Dec 2015 10:35:25 +0100 [thread overview]
Message-ID: <20151203093525.GQ17308@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <565FAC78.3030205@redhat.com>
On Thu, Dec 03, 2015 at 10:44:08AM +0800, Xunlei Pang wrote:
> > Nice, will you be looking for similar issues elsewhere in the scheduler
> > too?
>
> Sure :-)
Thanks!
> >>> in alloc_rootdomain() ?
> >> There is a "memset(rd, 0, sizeof(*rd))" in init_rootdomain(),
> >> so I don't think we need to do this in alloc_rootdomain().
> > Ah, right there is. Which also clears the mask for small systems.
>
> Yeah, maybe we can improve it using alloc_cpumask_var() with
> __GFP_ZERO instead of zalloc_cpumask_var() to avoid duplicate
> clean for small systems.
This isn't a performance critical path, so clarity and correctness are
more important than performance.
next prev parent reply other threads:[~2015-12-03 9:35 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-02 11:52 [PATCH] sched/core: Clear the root_domain cpumasks in init_rootdomain() Xunlei Pang
2015-12-02 12:34 ` Peter Zijlstra
2015-12-02 13:12 ` Xunlei Pang
2015-12-02 16:25 ` Peter Zijlstra
2015-12-03 2:44 ` Xunlei Pang
2015-12-03 8:28 ` Ingo Molnar
2015-12-03 11:52 ` Xunlei Pang
2015-12-04 8:09 ` Ingo Molnar
2015-12-04 8:27 ` Peter Zijlstra
2015-12-04 8:30 ` Ingo Molnar
2015-12-04 8:28 ` Xunlei Pang
2015-12-04 8:30 ` Ingo Molnar
2015-12-03 9:35 ` Peter Zijlstra [this message]
2015-12-04 11:52 ` [tip:locking/core] " tip-bot for Xunlei Pang
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