Re: [GIT PULL 0/2] perf annotate fix and report improvoment

From: Stephane Eranian
Date: Wed May 26 2010 - 16:11:23 EST


On Wed, May 26, 2010 at 9:32 PM, Arnaldo Carvalho de Melo
<acme@xxxxxxxxxxxxx> wrote:
> Em Wed, May 26, 2010 at 09:07:05PM +0200, Stephane Eranian escreveu:
>> Hi,
>>
>> +lkml et al.
>>
>> On Wed, May 26, 2010 at 8:23 PM, Arnaldo Carvalho de Melo
>> <acme@xxxxxxxxxxxxx> wrote:
>> > Em Wed, May 26, 2010 at 06:45:18PM +0200, Stephane Eranian escreveu:
>> >> Attached is the trace for
>> >> perf annotate -i ~/perf.data noploop
>> >>
>> >> I get no output at all (TUI is off). Copied over .debug tarball + perf.data.
>> >
>> > Looks like the bug I'm investigating now:
>> >
>> > build id event received for [kernel.kallsyms]: 54b1e7cc3cf52e0db255aab44ce7538eb62655b8
>> > build id event received for /tmp/noploop: 875ae61623e89f408b425ca0486a9ec99e3ac73e
>> > Looking at the vmlinux_path (5 entries long)
>> > No build_id in vmlinux, ignoring it
>> > No build_id in /boot/vmlinux, ignoring it
>> > No build_id in /boot/vmlinux-2.6.34-tip-default+, ignoring it
>> > build_id in /lib/modules/2.6.34-tip-default+/build/vmlinux is
>> > 3635a0e8dfc9a1afbd5627c2ba789e41d77d3cd1 while expected is
>> > 54b1e7cc3cf52e0db255aab44ce7538eb62655b8, ignoring it
>> > No build_id in /usr/lib/debug/lib/modules/2.6.34-tip-default+/vmlinux, ignoring it
>> >
>> > In my case it is not finding the vmlinux because I'm using RHEL6 Beta
>> > kernel without the respective kernel-debuginfo{-common} packages so it
>> > doesn't find the vmlinux, uses just /proc/kallsyms and that is not
>> > enough for annotation.
>> >
>> > In your case the problem is that we only cache the kallsyms file in the
>> > build-id cache ($HOME/.debug) and that is not enough for annotation, so
>> > I have to fix two things:
>> >
>> I can understand the issue with the kernel symbols.
>
> That has to be fixed and I've got some patches already for that, testing
> them now.
>
>> But in this example, I only really care about the symbols in the
>> noploop program (/tmp/noploop).
>>
>> Missing symbol support for the kernel should not cause perf to avoid
>> trying to resolve the symbols in other modules such as my user program
>> here.
>
> Right, my bad, I thought that the problem was about the kernel symbols.
>
> Then can you try replacing:
>
> perf annotate -i ~/perf.data noploop
>
> with:
>
> perf annotate -i ~/perf.data -d noploop
>
> And see if that helps?
>
Ok that works. But if I turned on TUI, then I cannot obtain
the same result. I am guessing it does not use the -d option.
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