5.15-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 edead3a55804739b2e4af0f35e9c7326264e7b22 ]
Without LRU item rotation, the shrinker visits only a few items on the end of the LRU list, and those would always be long-term OPEN files for NFSv4 workloads. That makes the filecache shrinker completely ineffective.
Adopt the same strategy as the inode LRU by using LRU_ROTATE.
Suggested-by: Dave Chinner david@fromorbit.com Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com --- fs/nfsd/filecache.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 5c9e3ff6397b0..849c010c6ef61 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -445,6 +445,7 @@ nfsd_file_dispose_list_delayed(struct list_head *dispose) * * Return values: * %LRU_REMOVED: @item was removed from the LRU + * %LRU_ROTATE: @item is to be moved to the LRU tail * %LRU_SKIP: @item cannot be evicted */ static enum lru_status @@ -483,7 +484,7 @@ nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru,
if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf->nf_flags)) { trace_nfsd_file_gc_referenced(nf); - return LRU_SKIP; + return LRU_ROTATE; }
if (!test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { @@ -525,7 +526,7 @@ nfsd_file_gc(void) unsigned long ret;
ret = list_lru_walk(&nfsd_file_lru, nfsd_file_lru_cb, - &dispose, LONG_MAX); + &dispose, list_lru_count(&nfsd_file_lru)); trace_nfsd_file_gc_removed(ret, list_lru_count(&nfsd_file_lru)); nfsd_file_gc_dispose_list(&dispose); }