The patch titled mm: unlockless reclaim has been added to the -mm tree. Its filename is mm-unlockless-reclaim.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: unlockless reclaim From: Nick Piggin <npiggin@xxxxxxx> unlock_page is fairly expensive. It can be avoided in page reclaim success path. By definition if we have any other references to the page it would be a bug anyway. Signed-off-by: Nick Piggin <npiggin@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmscan.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff -puN mm/vmscan.c~mm-unlockless-reclaim mm/vmscan.c --- a/mm/vmscan.c~mm-unlockless-reclaim +++ a/mm/vmscan.c @@ -781,7 +781,14 @@ static unsigned long shrink_page_list(st if (!mapping || !__remove_mapping(mapping, page)) goto keep_locked; - unlock_page(page); + /* + * At this point, we have no other references and there is + * no way to pick any more up (removed from LRU, removed + * from pagecache). Can use non-atomic bitops now (and + * we obviously don't have to worry about waking up a process + * waiting on the page lock, because there are no references. + */ + __clear_page_locked(page); free_it: nr_reclaimed++; if (!pagevec_add(&freed_pvec, page)) { _ Patches currently in -mm which might be from npiggin@xxxxxxx are origin.patch linux-next.patch mm-dirty-page-tracking-race-fix.patch mm-dirty-page-tracking-race-fix-fix.patch mm-xip-fix-fault-vs-sparse-page-invalidate-race.patch mm-xip-ext2-fix-block-allocation-race.patch vmscan-move-isolate_lru_page-to-vmscanc.patch mlock-mlocked-pages-are-unevictable.patch mmap-handle-mlocked-pages-during-map-remap-unmap.patch vmstat-mlocked-pages-statistics.patch mm-pagecache-insertion-fewer-atomics.patch mm-unlockless-reclaim.patch mm-page-lock-use-lock-bitops.patch fs-buffer-lock-use-lock-bitops.patch mm-page-allocator-minor-speedup.patch reiser4.patch likeliness-accounting-change-and-cleanup.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html