2013/1/25 Vincent Guittot vincent.guittot@linaro.org:
Le 25 janv. 2013 13:00, "Frederic Weisbecker" fweisbec@gmail.com a écrit :
2013/1/25 Vincent Guittot vincent.guittot@linaro.org:
This sequence is not the right one
I'm going to look for the saved trace to check the sequence above
I haven't been able to reproduce the bug that this patch was supposed to solved. The patch 2 and 3 seem enough to fix the nr_busy_cpus field. I will continue to try to reproduce it but it seems that it was a side effect of the 2 others fixes of the series
Ok. I just checked again as well and I can't find a scenario where this can happen. If you find it out or trigger the bug again, don't hesitate to resend this patch.
Ok. I'm going to update the patch serie without this patch
Actually your second patch may cause this, as it clears the NOHZ_IDLE flag on CPUs that are idle on boot and which could stay that way for a while. And your second patch is spotting something serious. I'll reply on it after more thoughts.