Re: [GIT PULL] perf fixes

[Ingo Molnar <mingo@kernel.org>]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Thu, Sep 12, 2013 at 11:10 AM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > But at least the "make install" problem is repeatable, though.
> 
> And now this new problem is repeatable too:
> 
>   # On a fully built kernel tree
>   perf record -g -e cycles:pp make -j
> 
> results in
> 
>   [ perf record: Woken up 27 times to write data ]
>   [ perf record: Captured and wrote 7.980 MB perf.data (~348659 samples) ]
>   0x1b4e0 [0]: failed to process type: -1970637019
> 
> where that number changes randomly, ie I get
> 
>   0x28dc58 [0]: failed to process type: 99257493
>   0x4100 [0]: failed to process type: -1144359783
>   0x29050 [0]: failed to process type: -972156963
>   ..
> 
> looks like perhaps some uninitialized variable somewhere?
> 
> Recording performance profiles of other (simpler?) loads still seems to 
> work. So it's something about that "make -j" that makes it crap out 
> (note that the tree is fully built, so not a lot actually gets *done*, 
> and the thing only takes a few seconds)

Hm, just to make sure, are you running a (very fresh) kernel that has this 
fix included:

d008d5258e9c perf: Fix up MMAP2 buffer space reservation

?

Thanks,

	Ingo