From: "Darrick J. Wong" djwong@kernel.org
[ Upstream commit b37c4c8339cd394ea6b8b415026603320a185651 ]
Now that we've allegedly worked out the problem of the per-cpu inodegc workers being scheduled on the wrong cpu, let's put in a debugging knob to let us know if a worker ever gets mis-scheduled again.
Signed-off-by: Darrick J. Wong djwong@kernel.org Reviewed-by: Dave Chinner dchinner@redhat.com Signed-off-by: Dave Chinner david@fromorbit.com Signed-off-by: Leah Rumancik leah.rumancik@gmail.com Acked-by: Darrick J. Wong djwong@kernel.org --- fs/xfs/xfs_icache.c | 2 ++ fs/xfs/xfs_mount.h | 3 +++ fs/xfs/xfs_super.c | 3 +++ 3 files changed, 8 insertions(+)
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c index ab8181f8d08a..02022164772d 100644 --- a/fs/xfs/xfs_icache.c +++ b/fs/xfs/xfs_icache.c @@ -1856,6 +1856,8 @@ xfs_inodegc_worker( struct llist_node *node = llist_del_all(&gc->list); struct xfs_inode *ip, *n;
+ ASSERT(gc->cpu == smp_processor_id()); + WRITE_ONCE(gc->items, 0);
if (!node) diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h index 3d58938a6f75..29f35169bf9c 100644 --- a/fs/xfs/xfs_mount.h +++ b/fs/xfs/xfs_mount.h @@ -66,6 +66,9 @@ struct xfs_inodegc { /* approximate count of inodes in the list */ unsigned int items; unsigned int shrinker_hits; +#if defined(DEBUG) || defined(XFS_WARN) + unsigned int cpu; +#endif };
/* diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 9b3af7611eaa..569960e4ea3a 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1062,6 +1062,9 @@ xfs_inodegc_init_percpu(
for_each_possible_cpu(cpu) { gc = per_cpu_ptr(mp->m_inodegc, cpu); +#if defined(DEBUG) || defined(XFS_WARN) + gc->cpu = cpu; +#endif init_llist_head(&gc->list); gc->items = 0; INIT_DELAYED_WORK(&gc->work, xfs_inodegc_worker);