Unverified Commit aa395641 authored by David Howells's avatar David Howells Committed by Christian Brauner
Browse files

netfs: Fix missing barriers by using clear_and_wake_up_bit() 



Use clear_and_wake_up_bit() rather than something like:

	clear_bit_unlock(NETFS_RREQ_IN_PROGRESS, &rreq->flags);
	wake_up_bit(&rreq->flags, NETFS_RREQ_IN_PROGRESS);

as there needs to be a barrier inserted between which is present in
clear_and_wake_up_bit().

Fixes: 288ace2f ("netfs: New writeback implementation")
Fixes: ee4cdf7b ("netfs: Speed up buffered reading")
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241213135013.2964079-8-dhowells@redhat.com


Reviewed-by: default avatarAkira Yokosawa <akiyks@gmail.com>
cc: Zilin Guan <zilin@seu.edu.cn>
cc: Akira Yokosawa <akiyks@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent f4d3cde4

fs/netfs/read_collect.c

+1 −2
Original line number Diff line number Diff line
@@ -379,8 +379,7 @@ static void netfs_rreq_assess(struct netfs_io_request *rreq) 
	task_io_account_read(rreq->transferred);



	trace_netfs_rreq(rreq, netfs_rreq_trace_wake_ip);

	clear_bit_unlock(NETFS_RREQ_IN_PROGRESS, &rreq->flags);

	wake_up_bit(&rreq->flags, NETFS_RREQ_IN_PROGRESS);

	clear_and_wake_up_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags);



	trace_netfs_rreq(rreq, netfs_rreq_trace_done);

	netfs_clear_subrequests(rreq, false);

fs/netfs/write_collect.c

+3 −6
Original line number Diff line number Diff line
@@ -501,8 +501,7 @@ static void netfs_collect_write_results(struct netfs_io_request *wreq) 
		goto need_retry;

	if ((notes & MADE_PROGRESS) && test_bit(NETFS_RREQ_PAUSE, &wreq->flags)) {

		trace_netfs_rreq(wreq, netfs_rreq_trace_unpause);

		clear_bit_unlock(NETFS_RREQ_PAUSE, &wreq->flags);

		wake_up_bit(&wreq->flags, NETFS_RREQ_PAUSE);

		clear_and_wake_up_bit(NETFS_RREQ_PAUSE, &wreq->flags);

	}



	if (notes & NEED_REASSESS) {
@@ -605,8 +604,7 @@ void netfs_write_collection_worker(struct work_struct *work) 


	_debug("finished");

	trace_netfs_rreq(wreq, netfs_rreq_trace_wake_ip);

	clear_bit_unlock(NETFS_RREQ_IN_PROGRESS, &wreq->flags);

	wake_up_bit(&wreq->flags, NETFS_RREQ_IN_PROGRESS);

	clear_and_wake_up_bit(NETFS_RREQ_IN_PROGRESS, &wreq->flags);



	if (wreq->iocb) {

		size_t written = min(wreq->transferred, wreq->len);
@@ -714,8 +712,7 @@ void netfs_write_subrequest_terminated(void *_op, ssize_t transferred_or_error, 


	trace_netfs_sreq(subreq, netfs_sreq_trace_terminated);



	clear_bit_unlock(NETFS_SREQ_IN_PROGRESS, &subreq->flags);

	wake_up_bit(&subreq->flags, NETFS_SREQ_IN_PROGRESS);

	clear_and_wake_up_bit(NETFS_SREQ_IN_PROGRESS, &subreq->flags);



	/* If we are at the head of the queue, wake up the collector,

	 * transferring a ref to it if we were the ones to do so.