diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2012-03-07 19:51:03 (GMT) |
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committer | Scott Wood <scottwood@freescale.com> | 2014-04-10 00:19:44 (GMT) |
commit | dfb845d5e9b283cf0c189d6f289722f5b67ddd1a (patch) | |
tree | eb1f4cd18235efc7c51a82004673408bad7453c8 /include/linux | |
parent | a98f37c17e021ac4bf1bfa589a40a32ffa117a03 (diff) | |
download | linux-fsl-qoriq-dfb845d5e9b283cf0c189d6f289722f5b67ddd1a.tar.xz |
rt: Introduce cpu_chill()
Retry loops on RT might loop forever when the modifying side was
preempted. Add cpu_chill() to replace cpu_relax(). cpu_chill()
defaults to cpu_relax() for non RT. On RT it puts the looping task to
sleep for a tick so the preempted task can make progress.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable-rt@vger.kernel.org
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/delay.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/delay.h b/include/linux/delay.h index a6ecb34..e23a7c0 100644 --- a/include/linux/delay.h +++ b/include/linux/delay.h @@ -52,4 +52,10 @@ static inline void ssleep(unsigned int seconds) msleep(seconds * 1000); } +#ifdef CONFIG_PREEMPT_RT_FULL +# define cpu_chill() msleep(1) +#else +# define cpu_chill() cpu_relax() +#endif + #endif /* defined(_LINUX_DELAY_H) */ |