5.10-stable review patch. If anyone has any objections, please let me know.
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From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit 0bac5a264d9a923f5b01f3521e1519a8d0358342 ]
Refactor the invariant part of nfsd_file_lru_walk_list() into a separate helper function.
Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/filecache.c | 29 ++++++++++++++++++++++------- 1 file changed, 22 insertions(+), 7 deletions(-)
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 0cd72c20fc12d..ffe46f3f33495 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -450,11 +450,31 @@ nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru, return LRU_SKIP; }
+/* + * Unhash items on @dispose immediately, then queue them on the + * disposal workqueue to finish releasing them in the background. + * + * cel: Note that between the time list_lru_shrink_walk runs and + * now, these items are in the hash table but marked unhashed. + * Why release these outside of lru_cb ? There's no lock ordering + * problem since lru_cb currently takes no lock. + */ +static void nfsd_file_gc_dispose_list(struct list_head *dispose) +{ + struct nfsd_file *nf; + + list_for_each_entry(nf, dispose, nf_lru) { + spin_lock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock); + nfsd_file_do_unhash(nf); + spin_unlock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock); + } + nfsd_file_dispose_list_delayed(dispose); +} + static unsigned long nfsd_file_lru_walk_list(struct shrink_control *sc) { LIST_HEAD(head); - struct nfsd_file *nf; unsigned long ret;
if (sc) @@ -464,12 +484,7 @@ nfsd_file_lru_walk_list(struct shrink_control *sc) ret = list_lru_walk(&nfsd_file_lru, nfsd_file_lru_cb, &head, LONG_MAX); - list_for_each_entry(nf, &head, nf_lru) { - spin_lock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock); - nfsd_file_do_unhash(nf); - spin_unlock(&nfsd_file_hashtbl[nf->nf_hashval].nfb_lock); - } - nfsd_file_dispose_list_delayed(&head); + nfsd_file_gc_dispose_list(&head); return ret; }