a9ba9a3b38
In a micro-benchmark that stresses the pagefault path, the down_read_trylock on the mmap_sem showed up quite high on the profile. Turns out this lock is bouncing between cpus quite a bit and thus is cache-cold a lot. This patch prefetches the lock (for write) as early as possible (and before some other somewhat expensive operations). With this patch, the down_read_trylock basically fell out of the top of profile. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| extable.c | ||
| fault.c | ||
| init.c | ||
| ioremap.c | ||
| k8topology.c | ||
| Makefile | ||
| mmap.c | ||
| numa.c | ||
| pageattr.c | ||
| srat.c | ||