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Date: Tue, 9 Feb 2016 11:09:36 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: =?utf-8?B?5bmz5p2+6ZuF5bezIC8gSElSQU1BVFXvvIxNQVNBTUk=?= 
	<masami.hiramatsu.pt@hitachi.com>,
        "'Martin KaFai Lau'" <kafai@fb.com>,
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        Ingo Molnar <mingo@redhat.com>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Josef Bacik <jbacik@fb.com>, Kernel Team <kernel-team@fb.com>
Subject: Re: [PATCH RESEND] kprobe: Use percpu counter to collect nhit
 statistics
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* Steven Rostedt <rostedt@goodmis.org> wrote:

> On Thu, 4 Feb 2016 10:24:12 +0000
> 平松雅巳 / HIRAMATU，MASAMI <masami.hiramatsu.pt@hitachi.com> wrote:
> 
> > From: Martin KaFai Lau [mailto:kafai@fb.com]
> > >
> > >When doing ebpf+kprobe on some hot TCP functions (e.g.
> > >tcp_rcv_established), the kprobe_dispatcher shows up in 'perf report'.
> > >
> > >In kprobe_dispatcher(), there is a lot of cache bouncing
> > >in 'tk->nhit++'.  'tk->nhit' and 'tk->tp.flags' also share
> > >the same cacheline.
> > >  
> > 
> > Ingo, could you consider to merge this?
> > 
> 
> Ingo, you can also add my
> 
>  Acked-by: Steven Rostedt <rostedt@goodmis.org>

Yeah, nice optimization, picked it up - thanks guys!

	Ingo