Messages in this thread | | | Subject | Re: [PATCH v2 10/10] kernel: might_fault does not imply might_sleep | From | Steven Rostedt <> | Date | Sun, 19 May 2013 12:06:19 -0400 |
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On Sun, 2013-05-19 at 16:34 +0300, Michael S. Tsirkin wrote:
> Right but we need to keep it working on upstream as well. > If I do preempt_enable under a spinlock upstream won't it > try to sleep under spinlock?
No it wont. A spinlock calls preempt_disable implicitly, and a preempt_enable() will not schedule unless preempt_count is zero, which it wont be under a spinlock.
If it did, there would be lots of bugs all over the place because this is done throughout the kernel (a preempt_enable() under a spinlock).
In other words, don't ever use preempt_enable_no_resched().
-- Steve
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