@@ -374,9 +374,7 @@ static ssize_t kbytestotal_show(struct kobject *kobj, struct attribute *attr,
u32 blk_size = osfs.os_bsize >> 10;
u64 result = osfs.os_blocks;
- while (blk_size >>= 1)
- result <<= 1;
-
+ result *= rounddown_pow_of_two(blk_size ?: 1);
return sprintf(buf, "%llu\n", result);
}
@@ -397,8 +395,7 @@ static ssize_t kbytesfree_show(struct kobject *kobj, struct attribute *attr,
u32 blk_size = osfs.os_bsize >> 10;
u64 result = osfs.os_bfree;
- while (blk_size >>= 1)
- result <<= 1;
+ result *= rounddown_pow_of_two(blk_size ?: 1);
return sprintf(buf, "%llu\n", result);
}
@@ -420,8 +417,7 @@ static ssize_t kbytesavail_show(struct kobject *kobj, struct attribute *attr,
u32 blk_size = osfs.os_bsize >> 10;
u64 result = osfs.os_bavail;
- while (blk_size >>= 1)
- result <<= 1;
+ result *= rounddown_pow_of_two(blk_size ?: 1);
return sprintf(buf, "%llu\n", result);
}
These shift loops seem to be trying to avoid doing a multiplication. We same effect can be achieved more transparently using rounddown_pow_of_two(). Even though there is a multiplication in the C code, the resulting machine code just does a single shift. As rounddown_pow_of_two() is not defined for 0, and as we cannot be positively use the blk_size is non-zero, use blk_size ?: 1. Signed-off-by: NeilBrown <neilb@suse.com> --- .../lustre/lustre/obdclass/lprocfs_status.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)