From: Coly Li <colyli@xxxxxxxxxx>
Commit f4aec6a09738 ("md/raid5: Factor out helper from
raid5_make_request() loop") added the following code block to check
whether the reshape range passed the stripe head range during thetime to
wait for a valid struct stripe_head object,
5971 if (unlikely(previous) &&
5972 stripe_ahead_of_reshape(mddev, conf, sh)) {
5973 /*
5974 * Expansion moved on while waiting for a stripe.
5975 * Expansion could still move past after this
5976 * test, but as we are holding a reference to
5977 * 'sh', we know that if that happens,
5978 * STRIPE_EXPANDING will get set and the expansion
5979 * won't proceed until we finish with the stripe.
5980 */
5981 ret = STRIPE_SCHEDULE_AND_RETRY;
5982 goto out_release;
5983 }
But from the code comments and context, the if statement should check
whether stripe_ahead_of_reshape() returns false, then the code logic can
match the context that reshape range went accross the sh range during
raid5_get_active_stripe().
And unlikely(previous) seems useless inside the if statement, and the
unlikely() should include all checking statemetns.
This patch has both of the above changes, hope it can make the code be
more comfortable.
Fixes: f4aec6a09738 ("md/raid5: Factor out helper from raid5_make_request() loop")
Signed-off-by: Coly Li <colyli@xxxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Cc: Yu Kuai <yukuai3@xxxxxxxxxx>
Cc: Xiao Ni <xni@xxxxxxxxxx>
Cc: Song Liu <song@xxxxxxxxxx>
---
drivers/md/raid5.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 39e7596e78c0..030e4672ab18 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5969,8 +5969,7 @@ static enum stripe_result make_stripe_request(struct mddev *mddev,
return STRIPE_FAIL;
}
- if (unlikely(previous) &&
- stripe_ahead_of_reshape(mddev, conf, sh)) {
+ if (unlikely(previous && !stripe_ahead_of_reshape(mddev, conf, sh))) {
/*
* Expansion moved on while waiting for a stripe.
* Expansion could still move past after this
--
2.39.5
