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From: Anton Blanchard <anton@samba.org>
To: fweisbec@gmail.com, mingo@elte.hu, paulus@samba.org,
	a.p.zijlstra@chello.nl
Cc: linux-kernel@vger.kernel.org
Subject: perf report fractal output issue
Date: Thu, 15 Oct 2009 09:57:26 +1100	[thread overview]
Message-ID: <20091014225726.GF4808@kryten> (raw)


Hi,

I noticed a problem where I wasn't always getting callchains:

# perf report
    98.47%  lock1_processes  [kernel]                [k] .lock_kernel

     0.91%  lock1_processes  [kernel]                [k] .fput


But a flat output confirmed the data is there:

# perf report -g flat
    98.47%  lock1_processes  [kernel]                             [k] .lock_kernel
            98.47%
                .lock_kernel
                .__posix_lock_file
                (nil)
                .fcntl_setlk
                .sys_fcntl
                syscall_exit
                0xfffb7d04844
                .testcase
                .testcase
                .affinitize
                .new_task
                .main
                0xfffb7c4933c
                0xfffb7c4955c
                (nil)

It looks like callchain__fprintf_graph() only prints the callchain if we
have at least one rb entry at the top. In my case all the associated
backtraces are identical so I assume we dont have to do any splitting.

Anton

             reply	other threads:[~2009-10-14 23:03 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-14 22:57 Anton Blanchard [this message]
2009-10-15 12:28 ` perf report fractal output issue Frederic Weisbecker
2009-10-15 23:41   ` Anton Blanchard
2009-10-20 21:53     ` Frederic Weisbecker

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