From 277f27e2f27752cd1a7901443d72e908ddea8a2e Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sun, 1 Mar 2020 18:21:43 -0500 Subject: [PATCH] SUNRPC/cache: Allow garbage collection of invalid cache entries If the cache entry never gets initialised, we want the garbage collector to be able to evict it. Otherwise if the upcall daemon fails to initialise the entry, we end up never expiring it. Signed-off-by: Trond Myklebust [ cel: resolved a merge conflict ] Signed-off-by: Chuck Lever --- include/linux/sunrpc/cache.h | 3 --- net/sunrpc/cache.c | 36 +++++++++++++++++++----------------- 2 files changed, 19 insertions(+), 20 deletions(-) diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h index 656882a50991e0..532cdbda43da0c 100644 --- a/include/linux/sunrpc/cache.h +++ b/include/linux/sunrpc/cache.h @@ -209,9 +209,6 @@ static inline void cache_put(struct cache_head *h, struct cache_detail *cd) static inline bool cache_is_expired(struct cache_detail *detail, struct cache_head *h) { - if (!test_bit(CACHE_VALID, &h->flags)) - return false; - return (h->expiry_time < seconds_since_boot()) || (detail->flush_time >= h->last_refresh); } diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 7f2e5d818e05ee..cd76ef2d26b82a 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -64,13 +64,14 @@ static struct cache_head *sunrpc_cache_find_rcu(struct cache_detail *detail, rcu_read_lock(); hlist_for_each_entry_rcu(tmp, head, cache_list) { - if (detail->match(tmp, key)) { - if (cache_is_expired(detail, tmp)) - continue; - tmp = cache_get_rcu(tmp); - rcu_read_unlock(); - return tmp; - } + if (!detail->match(tmp, key)) + continue; + if (test_bit(CACHE_VALID, &tmp->flags) && + cache_is_expired(detail, tmp)) + continue; + tmp = cache_get_rcu(tmp); + rcu_read_unlock(); + return tmp; } rcu_read_unlock(); return NULL; @@ -114,17 +115,18 @@ static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail, /* check if entry appeared while we slept */ hlist_for_each_entry_rcu(tmp, head, cache_list, lockdep_is_held(&detail->hash_lock)) { - if (detail->match(tmp, key)) { - if (cache_is_expired(detail, tmp)) { - sunrpc_begin_cache_remove_entry(tmp, detail); - freeme = tmp; - break; - } - cache_get(tmp); - spin_unlock(&detail->hash_lock); - cache_put(new, detail); - return tmp; + if (!detail->match(tmp, key)) + continue; + if (test_bit(CACHE_VALID, &tmp->flags) && + cache_is_expired(detail, tmp)) { + sunrpc_begin_cache_remove_entry(tmp, detail); + freeme = tmp; + break; } + cache_get(tmp); + spin_unlock(&detail->hash_lock); + cache_put(new, detail); + return tmp; } hlist_add_head_rcu(&new->cache_list, head);