From: Jakob Koschel jakobkoschel@gmail.com
[ Upstream commit 901aeda62efa21f2eae937bccb71b49ae531be06 ]
In preparation to limit the scope of a list iterator to the list traversal loop, use a dedicated pointer to iterate through the list [1].
Since that variable should not be used past the loop iteration, a separate variable is used to 'remember the current location within the loop'.
To either continue iterating from that position or skip the iteration (if the previous iteration was complete) list_prepare_entry() is used.
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWX... [1] Signed-off-by: Jakob Koschel jakobkoschel@gmail.com Link: https://lore.kernel.org/r/20220331220349.885126-1-jakobkoschel@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/drbd/drbd_main.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 55234a558e98..a7ed03476318 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -171,7 +171,7 @@ void tl_release(struct drbd_connection *connection, unsigned int barrier_nr, unsigned int set_size) { struct drbd_request *r; - struct drbd_request *req = NULL; + struct drbd_request *req = NULL, *tmp = NULL; int expect_epoch = 0; int expect_size = 0;
@@ -225,8 +225,11 @@ void tl_release(struct drbd_connection *connection, unsigned int barrier_nr, * to catch requests being barrier-acked "unexpectedly". * It usually should find the same req again, or some READ preceding it. */ list_for_each_entry(req, &connection->transfer_log, tl_requests) - if (req->epoch == expect_epoch) + if (req->epoch == expect_epoch) { + tmp = req; break; + } + req = list_prepare_entry(tmp, &connection->transfer_log, tl_requests); list_for_each_entry_safe_from(req, r, &connection->transfer_log, tl_requests) { if (req->epoch != expect_epoch) break;