lkml.org 
[lkml]   [2013]   [Oct]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] perf: disable mmap2 support

* Arnaldo Carvalho de Melo <acme@redhat.com> wrote:

> Em Wed, Oct 09, 2013 at 06:17:43PM +0200, Stephane Eranian escreveu:

> > This patch disables the mmap2 record format support for now. The
> > support needs a bit more work to cover VM_CLONE cases.
> >
> > The patch leaves attr->mmap2 defined, but returns an error if it is
> > set. That ensures no PERF_RECORD_MMAP2 record can be generated. Yet it
> > minimizes the reverts in the perf tool.
>
> Would be interesting to have a simple new tool that would detect all the
> mmaps that are shared in a given perf.data file, using the
> PERF_RECORD_MMAP2 information, and that tool should come together with
> the reworked kernel ABI, showing how it is used.

Indeed. Let's make that a requirement for the next round of mmap2 patches.

Issues like this is really why I hate not getting a fully functional
usecase together with a new ABI - it's _so_ easy to come up with something
subtly (or not so subtly) incomplete.

> A 'perf test' entry, based on the test programs you guys are using to
> test this functionality would be even better, showing that all cases
> you've been striving to cover are in fact covered by the new ABI.

That too, in addition to an actual tool that people can use.

Thanks,

Ingo


\
 
 \ /
  Last update: 2013-10-10 07:21    [W:1.090 / U:0.276 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site