[PATCH v7 09/16] SUNRPC/cache: use new hashtable implementation

Sasha Levin
2012-10-28T19:03:45Z

Switch cache to use the new hashtable implementation. This reduces the amount of
generic unrelated code in the cache implementation.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
---
net/sunrpc/cache.c | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index fc2f7aa..0490546 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -28,6 +28,7 @@
#include <linux/workqueue.h>
#include <linux/mutex.h>
#include <linux/pagemap.h>
+#include <linux/hashtable.h>
#include <asm/ioctls.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/cache.h>
@@ -524,19 +525,18 @@ EXPORT_SYMBOL_GPL(cache_purge);
* it to be revisited when cache info is available
*/

-#define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head))
-#define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE)
+#define DFR_HASH_BITS 9

#define DFR_MAX 300 /* ??? */

static DEFINE_SPINLOCK(cache_defer_lock);
static LIST_HEAD(cache_defer_list);
-static struct hlist_head cache_defer_hash[DFR_HASHSIZE];
+static DEFINE_HASHTABLE(cache_defer_hash, DFR_HASH_BITS);
static int cache_defer_cnt;

static void __unhash_deferred_req(struct cache_deferred_req *dreq)
{
- hlist_del_init(&dreq->hash);
+ hash_del(&dreq->hash);
if (!list_empty(&dreq->recent)) {
list_del_init(&dreq->recent);
cache_defer_cnt--;
@@ -545,10 +545,7 @@ static void __unhash_deferred_req(struct cache_deferred_req *dreq)

static void __hash_deferred_req(struct cache_deferred_req *dreq, struct cache_head *item)
{
- int hash = DFR_HASH(item);
-
- INIT_LIST_HEAD(&dreq->recent);
- hlist_add_head(&dreq->hash, &cache_defer_hash[hash]);
+ hash_add(cache_defer_hash, &dreq->hash, (unsigned long)item);
}

static void setup_deferral(struct cache_deferred_req *dreq,
@@ -600,7 +597,7 @@ static void cache_wait_req(struct cache_req *req, struct cache_head *item)
* to clean up
*/
spin_lock(&cache_defer_lock);
- if (!hlist_unhashed(&sleeper.handle.hash)) {
+ if (hash_hashed(&sleeper.handle.hash)) {
__unhash_deferred_req(&sleeper.handle);
spin_unlock(&cache_defer_lock);
} else {
@@ -671,12 +668,11 @@ static void cache_revisit_request(struct cache_head *item)
struct cache_deferred_req *dreq;
struct list_head pending;
struct hlist_node *lp, *tmp;
- int hash = DFR_HASH(item);

INIT_LIST_HEAD(&pending);
spin_lock(&cache_defer_lock);

- hlist_for_each_entry_safe(dreq, lp, tmp, &cache_defer_hash[hash], hash)
+ hash_for_each_possible_safe(cache_defer_hash, dreq, lp, tmp, hash, (unsigned long)item)
if (dreq->item == item) {
__unhash_deferred_req(dreq);
list_add(&dreq->recent, &pending);
@@ -1636,6 +1632,8 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net)
void __init cache_initialize(void)
{
INIT_DEFERRABLE_WORK(&cache_cleaner, do_cache_clean);
+
+ hash_init(cache_defer_hash);
}

int cache_register_net(struct cache_detail *cd, struct net *net)
--
1.7.12.4