On Fri, 13 May 2011 16:46:21 -0700 Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > In fork and exit it's quite common to take same rmap chain locks > again and again when the whole address space is processed for a > address space that has a lot of sharing. Also since the locking > has changed to always lock the root anon_vma this can be very > contended. > > This patch adds a simple wrapper to batch these lock acquisitions > and only reaquire the lock when another is needed. The main > advantage is that when multiple processes are doing this in > parallel they will avoid a lot of communication overhead > on the lock cache line. > > v2: Address review feedback. Drop lockbreak. Rename init function. Doesn't compile: include/linux/rmap.h: In function 'anon_vma_unlock_batch': include/linux/rmap.h:146: error: 'struct anon_vma' has no member named 'lock' mm/rmap.c: In function '__anon_vma_lock_batch': mm/rmap.c:1737: error: 'struct anon_vma' has no member named 'lock' mm/rmap.c:1739: error: 'struct anon_vma' has no member named 'lock' I think I reported this against the v1 patches. Please fix up the checkpatch errors? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>