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Subject[PATCH v2 4/4] sbitmap: simplify wrap check
Date
__sbitmap_get_word() doesn't warp if it's starting from the beginning
(i.e. initial hint is 0). Instead of stashing the original hint just set
@wrap accordingly.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
lib/sbitmap.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/sbitmap.c b/lib/sbitmap.c
index c18b518a16ba..d693d9213ceb 100644
--- a/lib/sbitmap.c
+++ b/lib/sbitmap.c
@@ -97,9 +97,11 @@ EXPORT_SYMBOL_GPL(sbitmap_resize);
static int __sbitmap_get_word(unsigned long *word, unsigned long depth,
unsigned int hint, bool wrap)
{
- unsigned int orig_hint = hint;
int nr;

+ /* don't wrap if starting from 0 */
+ wrap = wrap && hint;
+
while (1) {
nr = find_next_zero_bit(word, depth, hint);
if (unlikely(nr >= depth)) {
@@ -108,8 +110,8 @@ static int __sbitmap_get_word(unsigned long *word, unsigned long depth,
* offset to 0 in a failure case, so start from 0 to
* exhaust the map.
*/
- if (orig_hint && hint && wrap) {
- hint = orig_hint = 0;
+ if (hint && wrap) {
+ hint = 0;
continue;
}
return -1;
--
2.24.0
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