| commit | 3dd2ee4824b668a635d6d2bb6bc73f33708cab9f | |
| author | Linus Torvalds <torvalds@linux-foundation.org> | |
| Tue, 26 Apr 2011 01:10:58 +0000 (25 18:10 -0700) | ||
| committer | Linus Torvalds <torvalds@linux-foundation.org> | |
| Tue, 26 Apr 2011 01:10:58 +0000 (25 18:10 -0700) | ||
| tree | 40d8d017d9631ecefae76eb09e1bbecc23e17452 | treesnapshot (tar.gz zip) |
| parent | 5dd12af05ca6b7d052c06a9ca4ff755fdfa25ae4 | commitdiff |
bit_spinlock: don't play preemption games inside the busy loop
When we are waiting for the bit-lock to be released, and are looping
over the 'cpu_relax()' should not be doing anything else - otherwise we
miss the point of trying to do the whole 'cpu_relax()'.
Do the preemption enable/disable around the loop, rather than inside of
it.
Noticed when I was looking at the code generation for the dcache
__d_drop usage, and the code just looked very odd.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we are waiting for the bit-lock to be released, and are looping
over the 'cpu_relax()' should not be doing anything else - otherwise we
miss the point of trying to do the whole 'cpu_relax()'.
Do the preemption enable/disable around the loop, rather than inside of
it.
Noticed when I was looking at the code generation for the dcache
__d_drop usage, and the code just looked very odd.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| include/linux/bit_spinlock.h | diffblobblamehistory |