diff mbox series

[3/5] xfs: clean up scrub context if scrub setup returns -EDEADLOCK

Message ID 167243826794.683691.10735232030785081091.stgit@magnolia (mailing list archive)
State Accepted
Headers show
Series xfs: drain deferred work items when scrubbing | expand

Commit Message

Darrick J. Wong Dec. 30, 2022, 10:11 p.m. UTC 
From: Darrick J. Wong <djwong@kernel.org>

It has been a longstanding convention that online scrub and repair
functions can return -EDEADLOCK to signal that they weren't able to
obtain some necessary resource.  When this happens, the scrub framework
is supposed to release all resources attached to the scrub context, set
the TRY_HARDER flag in the scrub context flags, and try again.  In this
context, individual scrub functions are supposed to take all the
resources they (incorrectly) speculated were not necessary.

We're about to make it so that the functions that lock and wait for a
filesystem AG can also return EDEADLOCK to signal that we need to try
again with the drain waiters enabled.  Therefore, refactor
xfs_scrub_metadata to support this behavior for ->setup() functions.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
 fs/xfs/scrub/scrub.c |   28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)
diff mbox series

Patch

diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c
index 07a7a75f987f..50db13c5f626 100644
--- a/fs/xfs/scrub/scrub.c
+++ b/fs/xfs/scrub/scrub.c
@@ -491,23 +491,16 @@  xfs_scrub_metadata(
 
 	/* Set up for the operation. */
 	error = sc->ops->setup(sc);
+	if (error == -EDEADLOCK && !(sc->flags & XCHK_TRY_HARDER))
+		goto try_harder;
 	if (error)
 		goto out_teardown;
 
 	/* Scrub for errors. */
 	error = sc->ops->scrub(sc);
-	if (!(sc->flags & XCHK_TRY_HARDER) && error == -EDEADLOCK) {
-		/*
-		 * Scrubbers return -EDEADLOCK to mean 'try harder'.
-		 * Tear down everything we hold, then set up again with
-		 * preparation for worst-case scenarios.
-		 */
-		error = xchk_teardown(sc, 0);
-		if (error)
-			goto out_sc;
-		sc->flags |= XCHK_TRY_HARDER;
-		goto retry_op;
-	} else if (error || (sm->sm_flags & XFS_SCRUB_OFLAG_INCOMPLETE))
+	if (error == -EDEADLOCK && !(sc->flags & XCHK_TRY_HARDER))
+		goto try_harder;
+	if (error || (sm->sm_flags & XFS_SCRUB_OFLAG_INCOMPLETE))
 		goto out_teardown;
 
 	xchk_update_health(sc);
@@ -565,4 +558,15 @@  xfs_scrub_metadata(
 		error = 0;
 	}
 	return error;
+try_harder:
+	/*
+	 * Scrubbers return -EDEADLOCK to mean 'try harder'.  Tear down
+	 * everything we hold, then set up again with preparation for
+	 * worst-case scenarios.
+	 */
+	error = xchk_teardown(sc, 0);
+	if (error)
+		goto out_sc;
+	sc->flags |= XCHK_TRY_HARDER;
+	goto retry_op;
 }