lkml.org 
[lkml]   [2011]   [Sep]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] perf tools: Exit recording if events have non matching sample type
Em Thu, Sep 29, 2011 at 04:55:23PM -0600, David Ahern escreveu:
> On 09/29/2011 04:05 PM, Arnaldo Carvalho de Melo wrote:
> > Em Thu, Sep 29, 2011 at 06:01:08PM +0200, Jiri Olsa escreveu:
> >> Following command hangs on my setup:
> >> ./perf record -o perf.data -e ext4:ext4_mb_new_group_pa \
> >> -e LLC-loads -- date '+%F'
> >>
> >> because hardware and tracepoint events have different sample type.
> >>
> >> With the patch applied the record command displays
> >> "Non matching sample_type" message and exits.
> >
> > That is way too cryptic :-\
> >
> > What is that makes the sample type not match in this case? Can we make
> > it match instead?
> >
> > This is something to be properly fixed by _allowing_ non matching sample
> > types, the evsel/evlist abstractions are getting we close but not there
> > yet, multiple files in a perf.data/ directory are needed.
>
> >From what I can see sample_type has to be the same for all samples:
> https://lkml.org/lkml/2011/8/15/6

We could add a PERF_SAMPLE_ID2 that if present would be guaranteed to be
the last, or we can, as PeterZ prefers/suggests, to use one mmap per
sample id, then we know that if we're getting it on that mmap, it has
that sample_type.

For record that means we need to dump each per-sample_id mmap onto a
separate file, i.e. use a directory, etc.

But what I suggested as a short term solution was to check what is the
difference in the above case and then make them use a single sample
type, i.e. bow to the current restriction.
- Arnaldo



\
 
 \ /
  Last update: 2011-09-30 01:09    [from the cache]
©2003-2011 Jasper Spaans