Re: perf-record fix and UI improvement

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

On Fri, 2009-08-07 at 14:15 +0200, Pierre Habouzit wrote:
> While toying with perf, I've noticed that perf record can easily enter
> a busy loop when doing something as silly as:
> 
>     $ perf record -A ls
> 
> I've searched why and here are the patches:
> 
>  [PATCH 1/2] perf util: do_read should fail on EOF instead of busy-looping.
> 
>    Yeah, do_read here really wants to read a known size, not being able
>    to should die(), not busy-lopp ;)
>    That was the cause for the bug.
> 
> 
>  [PATCH 2/2] perf-record: improve -A UI for empty or non-existent perf.data
> 
>    Though with 1/2 `git record -A ls` would then fail miserably with
>    some kind of "cannot read" error, which sucks. So this patch
>    understands -A as a "append or create if file is empty or inexistant"
> 
>    This fact may deserve to be documented properly, if so just tell me
>    I'll send an updated patch for Documentation/
> 
> 
> I'm kind of new to the kernel world, so I hope I sent the patches to the
> proper persons.

You did well for a first time ;-)

The things you can improve for next time are:

 - placing these nice descriptions you made above into the patches
themselves, as esp the first patch has an empty changelog.

 - get your email right :-)

Anyway, I think Ingo already fixed that up for you, so

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>