sched: Check for pushing rt tasks after all scheduling

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The current method for pushing RT tasks after scheduling only
happens after a context switch. But we found cases where a task
is set up on a run queue to be pushed but the push never
happens because the schedule chooses the same task.

This bug was found with the help of Gregory Haskins and the use
of ftrace (trace_printk). It tooks several days for both of us
analyzing the code and the trace output to find this.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090729042526.205923666@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

...

This commit is contained in:

Steven Rostedt 2009-07-29 00:21:22 -04:00 • committed by Ingo Molnar

parent e709715915

commit da19ab5103

1 changed files with 27 additions and 11 deletions

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38

kernel/sched.c

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