Return-Path: Received: from mail-it1-f193.google.com ([209.85.166.193]:55577 "EHLO mail-it1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729497AbeJAVUh (ORCPT ); Mon, 1 Oct 2018 17:20:37 -0400 Received: by mail-it1-f193.google.com with SMTP id c23-v6so11592901itd.5 for ; Mon, 01 Oct 2018 07:42:28 -0700 (PDT) From: Trond Myklebust To: "J . Bruce Fields" Cc: linux-nfs@vger.kernel.org Subject: [PATCH 09/15] SUNRPC: Remove non-RCU protected lookup Date: Mon, 1 Oct 2018 10:41:51 -0400 Message-Id: <20181001144157.3515-10-trond.myklebust@hammerspace.com> In-Reply-To: <20181001144157.3515-9-trond.myklebust@hammerspace.com> References: <20181001144157.3515-1-trond.myklebust@hammerspace.com> <20181001144157.3515-2-trond.myklebust@hammerspace.com> <20181001144157.3515-3-trond.myklebust@hammerspace.com> <20181001144157.3515-4-trond.myklebust@hammerspace.com> <20181001144157.3515-5-trond.myklebust@hammerspace.com> <20181001144157.3515-6-trond.myklebust@hammerspace.com> <20181001144157.3515-7-trond.myklebust@hammerspace.com> <20181001144157.3515-8-trond.myklebust@hammerspace.com> <20181001144157.3515-9-trond.myklebust@hammerspace.com> MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: Clean up the cache code by removing the non-RCU protected lookup. Signed-off-by: Trond Myklebust --- Documentation/filesystems/nfs/rpc-cache.txt | 6 +- include/linux/sunrpc/cache.h | 6 -- net/sunrpc/cache.c | 61 ++------------------- 3 files changed, 7 insertions(+), 66 deletions(-) diff --git a/Documentation/filesystems/nfs/rpc-cache.txt b/Documentation/filesystems/nfs/rpc-cache.txt index ebcaaee21616..c4dac829db0f 100644 --- a/Documentation/filesystems/nfs/rpc-cache.txt +++ b/Documentation/filesystems/nfs/rpc-cache.txt @@ -84,7 +84,7 @@ Creating a Cache A message from user space has arrived to fill out a cache entry. It is in 'buf' of length 'len'. cache_parse should parse this, find the item in the - cache with sunrpc_cache_lookup, and update the item + cache with sunrpc_cache_lookup_rcu, and update the item with sunrpc_cache_update. @@ -95,7 +95,7 @@ Creating a Cache Using a cache ------------- -To find a value in a cache, call sunrpc_cache_lookup passing a pointer +To find a value in a cache, call sunrpc_cache_lookup_rcu passing a pointer to the cache_head in a sample item with the 'key' fields filled in. This will be passed to ->match to identify the target entry. If no entry is found, a new entry will be create, added to the cache, and @@ -116,7 +116,7 @@ item does become valid, the deferred copy of the request will be revisited (->revisit). It is expected that this method will reschedule the request for processing. -The value returned by sunrpc_cache_lookup can also be passed to +The value returned by sunrpc_cache_lookup_rcu can also be passed to sunrpc_cache_update to set the content for the item. A second item is passed which should hold the content. If the item found by _lookup has valid data, then it is discarded and a new item is created. This diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h index cf3e17ee2786..c3d67e893430 100644 --- a/include/linux/sunrpc/cache.h +++ b/include/linux/sunrpc/cache.h @@ -171,9 +171,6 @@ extern struct cache_head * sunrpc_cache_lookup_rcu(struct cache_detail *detail, struct cache_head *key, int hash); extern struct cache_head * -sunrpc_cache_lookup(struct cache_detail *detail, - struct cache_head *key, int hash); -extern struct cache_head * sunrpc_cache_update(struct cache_detail *detail, struct cache_head *new, struct cache_head *old, int hash); @@ -233,9 +230,6 @@ extern void sunrpc_cache_unregister_pipefs(struct cache_detail *); extern void sunrpc_cache_unhash(struct cache_detail *, struct cache_head *); /* Must store cache_detail in seq_file->private if using next three functions */ -extern void *cache_seq_start(struct seq_file *file, loff_t *pos); -extern void *cache_seq_next(struct seq_file *file, void *p, loff_t *pos); -extern void cache_seq_stop(struct seq_file *file, void *p); extern void *cache_seq_start_rcu(struct seq_file *file, loff_t *pos); extern void *cache_seq_next_rcu(struct seq_file *file, void *p, loff_t *pos); extern void cache_seq_stop_rcu(struct seq_file *file, void *p); diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 7593afed9036..593cf8607414 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -75,27 +75,6 @@ static struct cache_head *sunrpc_cache_find_rcu(struct cache_detail *detail, return NULL; } -static struct cache_head *sunrpc_cache_find(struct cache_detail *detail, - struct cache_head *key, int hash) -{ - struct hlist_head *head = &detail->hash_table[hash]; - struct cache_head *tmp; - - read_lock(&detail->hash_lock); - hlist_for_each_entry(tmp, head, cache_list) { - if (detail->match(tmp, key)) { - if (cache_is_expired(detail, tmp)) - /* This entry is expired, we will discard it. */ - break; - cache_get(tmp); - read_unlock(&detail->hash_lock); - return tmp; - } - } - read_unlock(&detail->hash_lock); - return NULL; -} - static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail, struct cache_head *key, int hash) @@ -154,20 +133,6 @@ struct cache_head *sunrpc_cache_lookup_rcu(struct cache_detail *detail, } EXPORT_SYMBOL_GPL(sunrpc_cache_lookup_rcu); -struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail, - struct cache_head *key, int hash) -{ - struct cache_head *ret; - - ret = sunrpc_cache_find(detail, key, hash); - if (ret) - return ret; - /* Didn't find anything, insert an empty entry */ - return sunrpc_cache_add_entry(detail, key, hash); -} -EXPORT_SYMBOL_GPL(sunrpc_cache_lookup); - - static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch); static void cache_fresh_locked(struct cache_head *head, time_t expiry, @@ -1369,17 +1334,7 @@ static void *__cache_seq_start(struct seq_file *m, loff_t *pos) struct cache_head, cache_list); } -void *cache_seq_start(struct seq_file *m, loff_t *pos) - __acquires(cd->hash_lock) -{ - struct cache_detail *cd = m->private; - - read_lock(&cd->hash_lock); - return __cache_seq_start(m, pos); -} -EXPORT_SYMBOL_GPL(cache_seq_start); - -void *cache_seq_next(struct seq_file *m, void *p, loff_t *pos) +static void *cache_seq_next(struct seq_file *m, void *p, loff_t *pos) { struct cache_head *ch = p; int hash = (*pos >> 32); @@ -1411,14 +1366,6 @@ void *cache_seq_next(struct seq_file *m, void *p, loff_t *pos) } EXPORT_SYMBOL_GPL(cache_seq_next); -void cache_seq_stop(struct seq_file *m, void *p) - __releases(cd->hash_lock) -{ - struct cache_detail *cd = m->private; - read_unlock(&cd->hash_lock); -} -EXPORT_SYMBOL_GPL(cache_seq_stop); - void *cache_seq_start_rcu(struct seq_file *m, loff_t *pos) __acquires(RCU) { @@ -1466,9 +1413,9 @@ static int c_show(struct seq_file *m, void *p) } static const struct seq_operations cache_content_op = { - .start = cache_seq_start, - .next = cache_seq_next, - .stop = cache_seq_stop, + .start = cache_seq_start_rcu, + .next = cache_seq_next_rcu, + .stop = cache_seq_stop_rcu, .show = c_show, }; -- 2.17.1