The patch titled fs: buffer lock use lock bitops has been added to the -mm tree. Its filename is fs-buffer-lock-use-lock-bitops.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: fs: buffer lock use lock bitops From: Nick Piggin <npiggin@xxxxxxx> trylock_buffer and unlock_buffer open and close a critical section. Hence, we can use the lock bitops to get the desired memory ordering. Signed-off-by: Nick Piggin <npiggin@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/buffer.c | 3 +-- include/linux/buffer_head.h | 2 +- 2 files changed, 2 insertions(+), 3 deletions(-) diff -puN fs/buffer.c~fs-buffer-lock-use-lock-bitops fs/buffer.c --- a/fs/buffer.c~fs-buffer-lock-use-lock-bitops +++ a/fs/buffer.c @@ -76,8 +76,7 @@ EXPORT_SYMBOL(__lock_buffer); void unlock_buffer(struct buffer_head *bh) { - smp_mb__before_clear_bit(); - clear_buffer_locked(bh); + clear_bit_unlock(BH_Lock, &bh->b_state); smp_mb__after_clear_bit(); wake_up_bit(&bh->b_state, BH_Lock); } diff -puN include/linux/buffer_head.h~fs-buffer-lock-use-lock-bitops include/linux/buffer_head.h --- a/include/linux/buffer_head.h~fs-buffer-lock-use-lock-bitops +++ a/include/linux/buffer_head.h @@ -322,7 +322,7 @@ static inline void wait_on_buffer(struct static inline int trylock_buffer(struct buffer_head *bh) { - return likely(!test_and_set_bit(BH_Lock, &bh->b_state)); + return likely(!test_and_set_bit_lock(BH_Lock, &bh->b_state)); } static inline void lock_buffer(struct buffer_head *bh) _ 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