Staging
v0.8.1
v0.8.1
https://github.com/torvalds/linux
Revision 98d8256739f2c6c636fa2da359f5949c739ae839 authored by Thomas Gleixner on 23 May 2007, 20:58:18 UTC, committed by Linus Torvalds on 24 May 2007, 03:14:15 UTC
The NOHZ patch contains a check for softirqs pending when a CPU goes idle. The BUG is unrelated to NOHZ, it just was made visible by the NOHZ patch. The BUG showed up mainly on P4 / hyperthreading enabled machines which lead the investigations into the wrong direction in the first place. The real cause is in cond_resched_softirq(): cond_resched_softirq() is enabling softirqs without invoking the softirq daemon when softirqs are pending. This leads to the warning message in the NOHZ idle code: t1 runs softirq disabled code on CPU#0 interrupt happens, softirq is raised, but deferred (softirqs disabled) t1 calls cond_resched_softirq() enables softirqs via _local_bh_enable() calls schedule() t2 runs t1 is migrated to CPU#1 t2 is done and invokes idle() NOHZ detects the pending softirq Fix: change _local_bh_enable() to local_bh_enable() so the softirq daemon is invoked. Thanks to Anant Nitya for debugging this with great patience ! Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Tip revision: 98d8256739f2c6c636fa2da359f5949c739ae839 authored by Thomas Gleixner on 23 May 2007, 20:58:18 UTC
Prevent going idle with softirq pending
Prevent going idle with softirq pending
Tip revision: 98d8256
File | Mode | Size |
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Kconfig | -rw-r--r-- | 8.4 KB |
Makefile | -rw-r--r-- | 823 bytes |
aztcd.c | -rw-r--r-- | 68.5 KB |
aztcd.h | -rw-r--r-- | 6.1 KB |
cdrom.c | -rw-r--r-- | 96.1 KB |
cdu31a.c | -rw-r--r-- | 84.7 KB |
cdu31a.h | -rw-r--r-- | 13.7 KB |
cm206.c | -rw-r--r-- | 45.1 KB |
cm206.h | -rw-r--r-- | 4.4 KB |
gscd.c | -rw-r--r-- | 19.1 KB |
gscd.h | -rw-r--r-- | 2.4 KB |
isp16.c | -rw-r--r-- | 9.6 KB |
isp16.h | -rw-r--r-- | 2.6 KB |
mcdx.c | -rw-r--r-- | 48.8 KB |
mcdx.h | -rw-r--r-- | 5.5 KB |
optcd.c | -rw-r--r-- | 50.4 KB |
optcd.h | -rw-r--r-- | 1.7 KB |
sbpcd.c | -rw-r--r-- | 166.7 KB |
sbpcd.h | -rw-r--r-- | 24.9 KB |
sjcd.c | -rw-r--r-- | 42.2 KB |
sjcd.h | -rw-r--r-- | 4.9 KB |
sonycd535.c | -rw-r--r-- | 47.8 KB |
sonycd535.h | -rw-r--r-- | 5.1 KB |
viocd.c | -rw-r--r-- | 21.8 KB |
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