Fix performance regression on lmbench select benchmark
Christian Borntraeger reported that reinstating cond_resched() with CONFIG_PREEMPT caused a performance regression on lmbench: For example select file 500: 23 microseconds 32 microseconds and that's really because we totally unnecessarily do the cond_resched() in the innermost loop of select(), which is just silly. This moves it out from the innermost loop (which only ever loops ove the bits in a single "unsigned long" anyway), which makes the performance regression go away. Reported-and-tested-by: NChristian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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