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Date: Sat, 31 Mar 2012 11:52:02 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>, David Smith <dsmith@redhat.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Steven Rostedt <rostedt@goodmis.org>,
        Denys Vlasenko <dvlasenk@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] tracing: fix the "old_pid" usage in
 trace_sched_process_exec()
Message-ID: <20120331095158.GA887@gmail.com>
References: <20120330162636.GA4857@redhat.com>
 <20120330162930.GA4902@redhat.com>
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* Oleg Nesterov <oleg@redhat.com> wrote:

> On 03/30, Oleg Nesterov wrote:
> >
> > 1. TRACE_EVENT(sched_process_exec) forgets to actually use the
> >    old pid argument, it sets ->old_pid = p->pid.
> >
> > 2. search_binary_handler() uses the wrong pid number. tracepoint
> >    needs the global pid_t from the root namespace, while old_pid
> >    is the virtual pid number as it seen by the tracer/parent.
> 
> Not really serious, but probably makes sense for 3.4. This fixes
> the recently merged 4ff16c25e2cc48cbe6956e356c38a25ac063a64d
> "tracepoint, vfs, sched: Add exec() tracepoint"

Thanks Oleg - will queue your fix up in tip:perf/urgent.

Thanks,

	Ingo