Commit 232128f6 authored Apr 01, 2022 by Jakob Koschel Committed by Greg Kroah-Hartman May 25, 2022

drbd: remove usage of list iterator variable after loop

[ 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=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/

 [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>

parent 83abb076

drivers/block/drbd/drbd_main.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -183,7 +183,7 @@ 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;

		@@ -237,8 +237,11 @@ 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;