From: Peter Zijlstra <peterz@infradead.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Ingo Molnar <mingo@kernel.org>, Andi Kleen <ak@linux.intel.com>,
Peter Anvin <hpa@zytor.com>, Mike Galbraith <bitbucket@online.de>,
Thomas Gleixner <tglx@linutronix.de>,
Arjan van de Ven <arjan@linux.intel.com>,
Frederic Weisbecker <fweisbec@gmail.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
linux-arch <linux-arch@vger.kernel.org>,
Len Brown <lenb@kernel.org>,
Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Subject: Re: [PATCH 2/7] sched: Add NEED_RESCHED to the preempt_count
Date: Wed, 11 Sep 2013 20:05:42 +0200 [thread overview]
Message-ID: <20130911180541.GR31370@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <CALCETrUECkOZkxao0d1467rEFcSF3jzddNo1awshE4uK-wsWGQ@mail.gmail.com>
On Wed, Sep 11, 2013 at 09:35:08AM -0700, Andy Lutomirski wrote:
> I bet that this improves cross-cpu wakeup latency, too -- the old code
> would presumably wake up the cpu and then immediately interrupt it.
Yeah,. its what clued Mike in to there being a problem.
> It might be nice to rename one or both of need_resched and
> test_need_resched, though -- the difference is somewhat inscrutable.
I agreed, I've just been unable to come up with anything sane.
The best I could come up with is renaming
{set,clear,test}_need_resched() to {}_tif_need_resched(), so we then end
up with test_tif_need_resched(), which is slightly more different from
need_resched().
Ideas?
next prev parent reply other threads:[~2013-09-11 18:06 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-10 13:08 [PATCH 0/7] preempt_count rework -v2 Peter Zijlstra
2013-09-10 13:08 ` [PATCH 1/7] sched: Introduce preempt_count accessor functions Peter Zijlstra
2013-09-10 13:08 ` [PATCH 2/7] sched: Add NEED_RESCHED to the preempt_count Peter Zijlstra
2013-09-11 1:59 ` Andy Lutomirski
2013-09-11 8:25 ` Peter Zijlstra
2013-09-11 11:06 ` Peter Zijlstra
2013-09-11 13:34 ` Mike Galbraith
2013-09-12 6:01 ` Mike Galbraith
2013-09-11 16:35 ` Andy Lutomirski
2013-09-11 18:05 ` Peter Zijlstra [this message]
2013-09-11 18:07 ` Andy Lutomirski
2013-09-11 11:14 ` Peter Zijlstra
2013-09-10 13:08 ` [PATCH 3/7] sched, arch: Create asm/preempt.h Peter Zijlstra
2013-09-10 13:08 ` [PATCH 4/7] sched: Create more preempt_count accessors Peter Zijlstra
2013-09-10 13:08 ` [PATCH 5/7] sched: Extract the basic add/sub preempt_count modifiers Peter Zijlstra
2013-09-10 13:08 ` [PATCH 6/7] sched, x86: Provide a per-cpu preempt_count implementation Peter Zijlstra
2013-09-10 13:27 ` Peter Zijlstra
2013-09-10 14:02 ` Eric Dumazet
2013-09-10 15:25 ` Peter Zijlstra
2013-09-10 16:48 ` Peter Zijlstra
2013-09-10 13:08 ` [PATCH 7/7] sched, x86: Optimize the preempt_schedule() call Peter Zijlstra
2013-09-10 13:42 ` Ingo Molnar
2013-09-10 13:55 ` Jan Beulich
2013-09-10 14:25 ` Ingo Molnar
2013-09-10 13:51 ` [PATCH 0/7] preempt_count rework -v2 Ingo Molnar
2013-09-10 13:56 ` Ingo Molnar
2013-09-10 15:14 ` Peter Zijlstra
2013-09-10 15:29 ` Arjan van de Ven
2013-09-10 15:35 ` Peter Zijlstra
2013-09-10 16:24 ` Linus Torvalds
2013-09-11 16:00 ` H. Peter Anvin
2013-09-10 16:34 ` Linus Torvalds
2013-09-10 16:45 ` Peter Zijlstra
2013-09-10 17:06 ` Linus Torvalds
2013-09-10 21:25 ` Peter Zijlstra
2013-09-10 21:43 ` Linus Torvalds
2013-09-10 21:51 ` H. Peter Anvin
2013-09-10 22:02 ` Linus Torvalds
2013-09-10 22:06 ` H. Peter Anvin
2013-09-11 13:13 ` Peter Zijlstra
2013-09-11 13:26 ` Peter Zijlstra
2013-09-11 15:29 ` H. Peter Anvin
2013-09-11 15:33 ` Linus Torvalds
2013-09-11 18:59 ` Peter Zijlstra
2013-09-11 23:02 ` Linus Torvalds
2013-09-12 2:20 ` Peter Zijlstra
2013-09-12 2:43 ` Linus Torvalds
2013-09-12 11:51 ` Peter Zijlstra
2013-09-12 12:25 ` Ingo Molnar
2013-09-13 7:25 ` Kevin Easton
2013-09-13 8:06 ` Peter Zijlstra
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