From 1863d77f15da0addcd293a1719fa5d3ef8cde3ca Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 1 Oct 2018 10:41:52 -0400 Subject: SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock Now that the reader functions are all RCU protected, use a regular spinlock rather than a reader/writer lock. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/cache.h | 2 +- net/sunrpc/cache.c | 46 ++++++++++++++++++++++---------------------- 2 files changed, 24 insertions(+), 24 deletions(-) diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h index c3d67e893430..5a3e95017fc6 100644 --- a/include/linux/sunrpc/cache.h +++ b/include/linux/sunrpc/cache.h @@ -67,7 +67,7 @@ struct cache_detail { struct module * owner; int hash_size; struct hlist_head * hash_table; - rwlock_t hash_lock; + spinlock_t hash_lock; char *name; void (*cache_put)(struct kref *); diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 593cf8607414..f96345b1180e 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -92,7 +92,7 @@ static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail, cache_init(new, detail); detail->init(new, key); - write_lock(&detail->hash_lock); + spin_lock(&detail->hash_lock); /* check if entry appeared while we slept */ hlist_for_each_entry_rcu(tmp, head, cache_list) { @@ -104,7 +104,7 @@ static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail, break; } cache_get(tmp); - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); cache_put(new, detail); return tmp; } @@ -113,7 +113,7 @@ static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail, hlist_add_head_rcu(&new->cache_list, head); detail->entries++; cache_get(new); - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); if (freeme) cache_put(freeme, detail); @@ -167,18 +167,18 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, struct cache_head *tmp; if (!test_bit(CACHE_VALID, &old->flags)) { - write_lock(&detail->hash_lock); + spin_lock(&detail->hash_lock); if (!test_bit(CACHE_VALID, &old->flags)) { if (test_bit(CACHE_NEGATIVE, &new->flags)) set_bit(CACHE_NEGATIVE, &old->flags); else detail->update(old, new); cache_fresh_locked(old, new->expiry_time, detail); - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); cache_fresh_unlocked(old, detail); return old; } - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); } /* We need to insert a new entry */ tmp = detail->alloc(); @@ -189,7 +189,7 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, cache_init(tmp, detail); detail->init(tmp, old); - write_lock(&detail->hash_lock); + spin_lock(&detail->hash_lock); if (test_bit(CACHE_NEGATIVE, &new->flags)) set_bit(CACHE_NEGATIVE, &tmp->flags); else @@ -199,7 +199,7 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail, cache_get(tmp); cache_fresh_locked(tmp, new->expiry_time, detail); cache_fresh_locked(old, 0, detail); - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); cache_fresh_unlocked(tmp, detail); cache_fresh_unlocked(old, detail); cache_put(old, detail); @@ -239,7 +239,7 @@ static int try_to_negate_entry(struct cache_detail *detail, struct cache_head *h { int rv; - write_lock(&detail->hash_lock); + spin_lock(&detail->hash_lock); rv = cache_is_valid(h); if (rv == -EAGAIN) { set_bit(CACHE_NEGATIVE, &h->flags); @@ -247,7 +247,7 @@ static int try_to_negate_entry(struct cache_detail *detail, struct cache_head *h detail); rv = -ENOENT; } - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); cache_fresh_unlocked(h, detail); return rv; } @@ -357,7 +357,7 @@ static struct delayed_work cache_cleaner; void sunrpc_init_cache_detail(struct cache_detail *cd) { - rwlock_init(&cd->hash_lock); + spin_lock_init(&cd->hash_lock); INIT_LIST_HEAD(&cd->queue); spin_lock(&cache_list_lock); cd->nextcheck = 0; @@ -377,11 +377,11 @@ void sunrpc_destroy_cache_detail(struct cache_detail *cd) { cache_purge(cd); spin_lock(&cache_list_lock); - write_lock(&cd->hash_lock); + spin_lock(&cd->hash_lock); if (current_detail == cd) current_detail = NULL; list_del_init(&cd->others); - write_unlock(&cd->hash_lock); + spin_unlock(&cd->hash_lock); spin_unlock(&cache_list_lock); if (list_empty(&cache_list)) { /* module must be being unloaded so its safe to kill the worker */ @@ -438,7 +438,7 @@ static int cache_clean(void) struct hlist_head *head; struct hlist_node *tmp; - write_lock(¤t_detail->hash_lock); + spin_lock(¤t_detail->hash_lock); /* Ok, now to clean this strand */ @@ -455,7 +455,7 @@ static int cache_clean(void) break; } - write_unlock(¤t_detail->hash_lock); + spin_unlock(¤t_detail->hash_lock); d = current_detail; if (!ch) current_index ++; @@ -510,9 +510,9 @@ void cache_purge(struct cache_detail *detail) struct hlist_node *tmp = NULL; int i = 0; - write_lock(&detail->hash_lock); + spin_lock(&detail->hash_lock); if (!detail->entries) { - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); return; } @@ -524,13 +524,13 @@ void cache_purge(struct cache_detail *detail) detail->entries--; set_bit(CACHE_CLEANED, &ch->flags); - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); cache_fresh_unlocked(ch, detail); cache_put(ch, detail); - write_lock(&detail->hash_lock); + spin_lock(&detail->hash_lock); } } - write_unlock(&detail->hash_lock); + spin_unlock(&detail->hash_lock); } EXPORT_SYMBOL_GPL(cache_purge); @@ -1873,13 +1873,13 @@ EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs); void sunrpc_cache_unhash(struct cache_detail *cd, struct cache_head *h) { - write_lock(&cd->hash_lock); + spin_lock(&cd->hash_lock); if (!hlist_unhashed(&h->cache_list)){ hlist_del_init_rcu(&h->cache_list); cd->entries--; - write_unlock(&cd->hash_lock); + spin_unlock(&cd->hash_lock); cache_put(h, cd); } else - write_unlock(&cd->hash_lock); + spin_unlock(&cd->hash_lock); } EXPORT_SYMBOL_GPL(sunrpc_cache_unhash); -- cgit v1.2.1