Messages in this thread | | | Date | Wed, 20 Nov 2013 22:14:02 +0200 | From | Eliezer Tamir <> | Subject | Re: [PATCH 6/7] sched: Clean up preempt_enable_no_resched() abuse |
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On 20/11/2013 20:15, Peter Zijlstra wrote: > There are options (CONFIG_PREEMPT_RCU) that allow scheduling while > holding rcu_read_lock(). > > Also, preempt_enable() only schedules when its possible to schedule, so > calling it when you know you cannot schedule is no issue. >
I have no issue with you changing busy_loop_us_clock() to use a regular preempt enable.
I think that we still need to only do this if config preempt debug is on. When it's off we should use the alternate implementation. We are silencing a warning, but this is a performance critical path, and we think we know what we are doing.
I tried to explain this in the comments. If you think my comments are not clear enough, I'm open to suggestions.
Cheers, Eliezer
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