printk/sched: Introduce special printk_sched() for those awkward moments
authorPeter Zijlstra <a.p.zijlstra@chello.nl>
Mon, 27 Feb 2012 09:47:00 +0000 (10:47 +0100)
committerIngo Molnar <mingo@elte.hu>
Mon, 12 Mar 2012 19:43:16 +0000 (20:43 +0100)
commit3ccf3e8306156a28213adc720aba807e9a901ad5
tree5b9db344b702299ea7eb53fbff3d0d74707d40ec
parent554cecaf733623b327eef9652b65965eb1081b81
printk/sched: Introduce special printk_sched() for those awkward moments

There's a few awkward printk()s inside of scheduler guts that people
prefer to keep but really are rather deadlock prone. Fudge around it
by storing the text in a per-cpu buffer and poll it using the existing
printk_tick() handler.

This will drop output when its more frequent than once a tick, however
only the affinity thing could possible go that fast and for that just
one should suffice to notify the admin he's done something silly..

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-wua3lmkt3dg8nfts66o6brne@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
include/linux/printk.h
kernel/printk.c
kernel/sched/core.c
kernel/sched/rt.c