diff options
| author |   Juergen Gross <jgross@suse.com> | 2022-03-11 11:35:27 +0100 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2022-03-11 05:15:33 -0700 |
| commit | 85d9abcd7331566781b93ff46e4bccd4806ef2b2 (patch) | |
| tree | 2c581e63393a0e7c1a15f396d77c10d1af889736 /drivers/block | |
| parent | Merge branch 'md-next' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md into for-5.18/drivers (diff) | |
| download | linux-dev-85d9abcd7331566781b93ff46e4bccd4806ef2b2.tar.xz linux-dev-85d9abcd7331566781b93ff46e4bccd4806ef2b2.zip | |
xen/blkfront: speed up purge_persistent_grants()
purge_persistent_grants() is scanning the grants list for persistent
grants being no longer in use by the backend. When having found such a
grant, it will be set to "invalid" and pushed to the tail of the list.
Instead of pushing it directly to the end of the list, add it first to
a temporary list, avoiding to scan those entries again in the main
list traversal. After having finished the scan, append the temporary
list to the grant list.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20220311103527.12931-1-jgross@suse.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/xen-blkfront.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index ccd0dd0c6b83..5d04e480f36a 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -2521,6 +2521,7 @@ static void purge_persistent_grants(struct blkfront_info *info) for_each_rinfo(info, rinfo, i) { struct grant *gnt_list_entry, *tmp; + LIST_HEAD(grants); spin_lock_irqsave(&rinfo->ring_lock, flags); @@ -2539,9 +2540,11 @@ static void purge_persistent_grants(struct blkfront_info *info) gnttab_end_foreign_access(gnt_list_entry->gref, 0, 0UL); rinfo->persistent_gnts_c--; gnt_list_entry->gref = GRANT_INVALID_REF; - list_add_tail(&gnt_list_entry->node, &rinfo->grants); + list_add_tail(&gnt_list_entry->node, &grants); } + list_splice_tail(&grants, &rinfo->grants); + spin_unlock_irqrestore(&rinfo->ring_lock, flags); } } |