From 10d470849a7c6dd360e8ad4770160ad7af9adb4b Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 30 Jul 2012 14:41:06 -0700 Subject: [PATCH] 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 --- fs/ext3/balloc.c | 2 +- fs/ext3/bitmap.c | 12 +----------- 2 files changed, 2 insertions(+), 12 deletions(-) diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c index 25cd6089211..90d901f0486 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 909d13e2656..ef9c643e8e9 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 */