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* Hard lockup with timer events
@ 2009-10-29 19:15 Soeren Sandmann
  2009-11-11  4:50 ` Frederic Weisbecker
  2009-11-11 13:48 ` Peter Zijlstra
  0 siblings, 2 replies; 5+ messages in thread
From: Soeren Sandmann @ 2009-10-29 19:15 UTC (permalink / raw)
  To: linux-kernel, mingo; +Cc: a.p.zijlstra, fweisbec, tglx, acme, rosted, paulus

Hi,

This program

        http://www.daimi.au.dk/~sandmann/lockup.c

locks up hard for me on a Pentium 4 in 32 bit mode, with the hrtimer
patches applied (-tip for example).

What the program does is spawn a thread that just spins, and then 400
threads that each create a performance counter of type
PERF_COUNT_SW_CPU_CLOCK and a sample period of 1000000 and a
sample_type of

        PERF_SAMPLE_IP | PERF_SAMPLE_TID | PERF_SAMPLE_CALLCHAIN

These threads then map the event buffer and read it continuously.

It does not apparently lock up if SAMPLE_CALLCHAIN is removed; also I
cannot get it to lock up on Core 2 Duo in either 32 or 64 bit mode.


Soren

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2009-11-11 16:34 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-10-29 19:15 Hard lockup with timer events Soeren Sandmann
2009-11-11  4:50 ` Frederic Weisbecker
2009-11-11 13:23   ` Peter Zijlstra
2009-11-11 16:34     ` Frederic Weisbecker
2009-11-11 13:48 ` Peter Zijlstra

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