[PATCH 08/10 v7] sunrpc: New helper cache_delete_entry for deleting cache_head directly

Kinglong Mee
2015-07-11T12:51:25Z

A new helper cache_delete_entry() for delete cache_head from
cache_detail directly.

It will be used by pin_kill, so make sure the cache_detail is valid
before deleting is needed.

Because pin_kill is not many times, so the influence of performance
is accepted.

v7, same as v6.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
---
include/linux/sunrpc/cache.h | 1 +
net/sunrpc/cache.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)

diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h
index ecc0ff6..5a4b921 100644
--- a/include/linux/sunrpc/cache.h
+++ b/include/linux/sunrpc/cache.h
@@ -210,6 +210,7 @@ extern int cache_check(struct cache_detail *detail,
struct cache_head *h, struct cache_req *rqstp);
extern void cache_flush(void);
extern void cache_purge(struct cache_detail *detail);
+extern void cache_delete_entry(struct cache_detail *cd, struct cache_head *h);
#define NEVER (0x7FFFFFFF)
extern void __init cache_initialize(void);
extern int cache_register_net(struct cache_detail *cd, struct net *net);
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index ad2155c..8a27483 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -458,6 +458,36 @@ static int cache_clean(void)
return rv;
}

+void cache_delete_entry(struct cache_detail *detail, struct cache_head *h)
+{
+ struct cache_detail *tmp;
+
+ if (!detail || !h)
+ return;
+
+ spin_lock(&cache_list_lock);
+ list_for_each_entry(tmp, &cache_list, others) {
+ if (tmp == detail)
+ goto found;
+ }
+ spin_unlock(&cache_list_lock);
+ printk(KERN_WARNING "%s: Deleted cache detail %p\n", __func__, detail);
+ return ;
+
+found:
+ write_lock(&detail->hash_lock);
+
+ list_del_init(&h->cache_list);
+ detail->entries--;
+ set_bit(CACHE_CLEANED, &h->flags);
+
+ write_unlock(&detail->hash_lock);
+ spin_unlock(&cache_list_lock);
+
+ cache_put(h, detail);
+}
+EXPORT_SYMBOL_GPL(cache_delete_entry);
+
/*
* We want to regularly clean the cache, so we need to schedule some work ...
*/
--
2.4.3