diff options
| author | Christian Ehrhardt <ehrhardt@de.ibm.com> | 2006-03-09 17:33:49 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-09 19:47:38 -0800 |
| commit | 96567161de0ceed45cd2eb0e5380e3c797f5c0f4 (patch) | |
| tree | eb1cf052c95b95052e281f9a0d33ea025ce39dc5 /arch/x86_64/lib/memmove.c | |
| parent | 6a88231fc7da311e4da4ce2011d1a132c80c145a (diff) | |
[PATCH] s390: Increase spinlock retry code performance
Currently the code tries up to spin_retry times to grab a lock using the cs
instruction. The cs instruction has exclusive access to a memory region
and therefore invalidates the appropiate cache line of all other cpus. If
there is contention on a lock this leads to cache line trashing. This can
be avoided if we first check wether a cs instruction is likely to succeed
before the instruction gets actually executed.
Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/x86_64/lib/memmove.c')
0 files changed, 0 insertions, 0 deletions