Replace the while loop that unecessarily checks for a NULL bio in the fast
path witch a simple goto loop.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/bio.c | 35 +++++++++++++++++------------------
1 file changed, 17 insertions(+), 18 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index 67e51ac..e4682ec 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1745,26 +1745,25 @@ static inline bool bio_remaining_done(struct bio *bio)
**/
void bio_endio(struct bio *bio)
{
- while (bio) {
- if (unlikely(!bio_remaining_done(bio)))
- break;
+again:
+ if (unlikely(!bio_remaining_done(bio)))
+ return;
- /*
- * Need to have a real endio function for chained bios,
- * otherwise various corner cases will break (like stacking
- * block devices that save/restore bi_end_io) - however, we want
- * to avoid unbounded recursion and blowing the stack. Tail call
- * optimization would handle this, but compiling with frame
- * pointers also disables gcc's sibling call optimization.
- */
- if (bio->bi_end_io == bio_chain_endio) {
- bio = __bio_chain_endio(bio);
- } else {
- if (bio->bi_end_io)
- bio->bi_end_io(bio);
- bio = NULL;
- }
+ /*
+ * Need to have a real endio function for chained bios, otherwise
+ * various corner cases will break (like stacking block devices that
+ * save/restore bi_end_io) - however, we want to avoid unbounded
+ * recursion and blowing the stack. Tail call optimization would
+ * handle this, but compiling with frame pointers also disables
+ * gcc's sibling call optimization.
+ */
+ if (bio->bi_end_io == bio_chain_endio) {
+ bio = __bio_chain_endio(bio);
+ goto again;
}
+
+ if (bio->bi_end_io)
+ bio->bi_end_io(bio);
}
EXPORT_SYMBOL(bio_endio);
--
2.1.4
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