The patch titled ext2: speed up file creates by optimizing rec_len functions has been removed from the -mm tree. Its filename was ext2-speed-up-file-creates-by-optimizing-rec_len-functions.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: ext2: speed up file creates by optimizing rec_len functions From: Eric Sandeen <sandeen@xxxxxxxxxx> The addition of 64k block capability in the rec_len_from_disk and rec_len_to_disk functions added a bit of math overhead which slows down file create workloads needlessly when the architecture cannot even support 64k blocks, thanks to page size limits. The directory entry checking can also be optimized a bit by sprinkling in some unlikely() conditions to move the error handling out of line. bonnie++ sequential file creates on a 512MB ramdisk speeds up from about 2200/s to about 2500/s, about a 14% improvement. Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> Cc: Jan Kara <jack@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/ext2/dir.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff -puN fs/ext2/dir.c~ext2-speed-up-file-creates-by-optimizing-rec_len-functions fs/ext2/dir.c --- a/fs/ext2/dir.c~ext2-speed-up-file-creates-by-optimizing-rec_len-functions +++ a/fs/ext2/dir.c @@ -28,21 +28,30 @@ typedef struct ext2_dir_entry_2 ext2_dirent; +/* + * Tests against MAX_REC_LEN etc were put in place for 64k block + * sizes; if that is not possible on this arch, we can skip + * those tests and speed things up. + */ static inline unsigned ext2_rec_len_from_disk(__le16 dlen) { unsigned len = le16_to_cpu(dlen); +#if (PAGE_CACHE_SIZE >= 65536) if (len == EXT2_MAX_REC_LEN) return 1 << 16; +#endif return len; } static inline __le16 ext2_rec_len_to_disk(unsigned len) { +#if (PAGE_CACHE_SIZE >= 65536) if (len == (1 << 16)) return cpu_to_le16(EXT2_MAX_REC_LEN); else BUG_ON(len > (1 << 16)); +#endif return cpu_to_le16(len); } @@ -129,15 +138,15 @@ static void ext2_check_page(struct page p = (ext2_dirent *)(kaddr + offs); rec_len = ext2_rec_len_from_disk(p->rec_len); - if (rec_len < EXT2_DIR_REC_LEN(1)) + if (unlikely(rec_len < EXT2_DIR_REC_LEN(1))) goto Eshort; - if (rec_len & 3) + if (unlikely(rec_len & 3)) goto Ealign; - if (rec_len < EXT2_DIR_REC_LEN(p->name_len)) + if (unlikely(rec_len < EXT2_DIR_REC_LEN(p->name_len))) goto Enamelen; - if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1)) + if (unlikely(((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))) goto Espan; - if (le32_to_cpu(p->inode) > max_inumber) + if (unlikely(le32_to_cpu(p->inode) > max_inumber)) goto Einumber; } if (offs != limit) _ Patches currently in -mm which might be from sandeen@xxxxxxxxxx are linux-next.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