From: Akinobu Mita Date: Mon, 30 Jul 2012 21:41:06 +0000 (-0700) Subject: ext3: use memweight() X-Git-Tag: Ubuntu-5.2.0-15.16~17485^2~66 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=10d470849a7c6dd360e8ad4770160ad7af9adb4b;p=mirror_ubuntu-eoan-kernel.git ext3: use memweight() Convert ext3_count_free() to use memweight() instead of table lookup based counting clear bits implementation. This change only affects the code segments enabled by EXT3FS_DEBUG. Note that this memweight() call can't be replaced with a single bitmap_weight() call, although the pointer to the memory area is aligned to long-word boundary. Because the size of the memory area may not be a multiple of BITS_PER_LONG, then it returns wrong value on big-endian architecture. This also includes the following changes. - Remove unnecessary map == NULL check in ext3_count_free() which always takes non-null pointer as the memory area. - Fix printk format warning that only reveals with EXT3FS_DEBUG. Signed-off-by: Akinobu Mita Acked-by: Jan Kara Cc: Andreas Dilger Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c index 25cd60892116..90d901f0486b 100644 --- a/fs/ext3/balloc.c +++ b/fs/ext3/balloc.c @@ -1813,7 +1813,7 @@ ext3_fsblk_t ext3_count_free_blocks(struct super_block *sb) brelse(bitmap_bh); printk("ext3_count_free_blocks: stored = "E3FSBLK ", computed = "E3FSBLK", "E3FSBLK"\n", - le32_to_cpu(es->s_free_blocks_count), + (ext3_fsblk_t)le32_to_cpu(es->s_free_blocks_count), desc_count, bitmap_count); return bitmap_count; #else diff --git a/fs/ext3/bitmap.c b/fs/ext3/bitmap.c index 909d13e26560..ef9c643e8e9d 100644 --- a/fs/ext3/bitmap.c +++ b/fs/ext3/bitmap.c @@ -11,19 +11,9 @@ #ifdef EXT3FS_DEBUG -static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0}; - unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars) { - unsigned int i; - unsigned long sum = 0; - - if (!map) - return (0); - for (i = 0; i < numchars; i++) - sum += nibblemap[map->b_data[i] & 0xf] + - nibblemap[(map->b_data[i] >> 4) & 0xf]; - return (sum); + return numchars * BITS_PER_BYTE - memweight(map->b_data, numchars); } #endif /* EXT3FS_DEBUG */