From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>,
akpm@linuxfoundation.org, rostedt@goodmis.org,
linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 6/6] percpu: Add preemption checks to __this_cpu ops
Date: Thu, 17 Oct 2013 23:13:17 +0200 [thread overview]
Message-ID: <20131017211317.GZ10651@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <00000141c7de3c3e-51b4dd7b-901e-466e-829a-b1f7c4b9ec90-000000@email.amazonses.com>
On Thu, Oct 17, 2013 at 07:22:12PM +0000, Christoph Lameter wrote:
> On Wed, 16 Oct 2013, Peter Zijlstra wrote:
> > diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
> > index 8729723..95e3532 100644
> > --- a/arch/x86/include/asm/preempt.h
> > +++ b/arch/x86/include/asm/preempt.h
> > @@ -13,12 +13,12 @@ DECLARE_PER_CPU(int, __preempt_count);
> > */
> > static __always_inline int preempt_count(void)
> > {
> > - return __this_cpu_read_4(__preempt_count) & ~PREEMPT_NEED_RESCHED;
> > + return raw_cpu_read_4(__preempt_count) & ~PREEMPT_NEED_RESCHED;
> > }
> >
> > static __always_inline void preempt_count_set(int pc)
> > {
> > - __this_cpu_write_4(__preempt_count, pc);
> > + raw_cpu_write_4(__preempt_count, pc);
> > }
>
> Huh? What happened here? Why do we use the __this_cpu_read_4 here?
> This should be just raw_cpu_write()
Header inclusion hell; I could only easily get away with including
asm/percpu.h, so I had to use the _4 stuff.
next prev parent reply other threads:[~2013-10-17 21:13 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-15 17:47 [PATCH 0/6] percpu: Implement Preemption checks for __this_cpu operations V4b Christoph Lameter
2013-10-15 17:47 ` [PATCH 1/6] net: ip4_datagram_connect: Use correct form of statistics update Christoph Lameter
2013-10-15 18:36 ` Eric Dumazet
2013-10-16 6:09 ` Ingo Molnar
2013-10-16 8:35 ` Peter Zijlstra
2013-10-16 9:14 ` Eric Dumazet
2013-10-16 9:26 ` Ingo Molnar
2013-10-16 14:27 ` Christoph Lameter
2013-10-16 14:37 ` Eric Dumazet
2013-10-15 17:47 ` [PATCH 2/6] percpu: Add raw_cpu_ops Christoph Lameter
2013-10-15 17:47 ` [PATCH 3/6] mm: Use raw_cpu ops for determining current NUMA node Christoph Lameter
2013-10-16 8:38 ` Peter Zijlstra
2013-10-16 14:22 ` Christoph Lameter
2013-10-15 17:47 ` [PATCH 4/6] Use raw_cpu_write for initialization of per cpu refcount Christoph Lameter
2013-10-16 8:43 ` Peter Zijlstra
2013-10-15 17:47 ` [PATCH 5/6] net: __this_cpu_inc in route.c Christoph Lameter
2013-10-16 8:46 ` Peter Zijlstra
2013-10-16 9:22 ` Eric Dumazet
2013-10-16 10:25 ` Peter Zijlstra
2013-10-16 15:07 ` Christoph Lameter
2013-10-15 17:47 ` [PATCH 6/6] percpu: Add preemption checks to __this_cpu ops Christoph Lameter
2013-10-16 8:49 ` Peter Zijlstra
2013-10-16 15:09 ` Christoph Lameter
2013-10-16 15:36 ` Peter Zijlstra
2013-10-16 15:55 ` Christoph Lameter
2013-10-16 16:25 ` Peter Zijlstra
2013-10-16 16:52 ` Steven Rostedt
2013-10-16 17:11 ` Peter Zijlstra
2013-10-16 17:39 ` Steven Rostedt
2013-10-16 18:38 ` Peter Zijlstra
2013-10-17 19:22 ` Christoph Lameter
2013-10-17 21:13 ` Peter Zijlstra [this message]
[not found] <20131011175518.634285474@linux.com>
2013-10-11 17:54 ` Christoph Lameter
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