@@ -2028,6 +2028,10 @@ static DEFINE_SPINLOCK(nfs_access_lru_lock);
static LIST_HEAD(nfs_access_lru_list);
static atomic_long_t nfs_access_nr_entries;
+static unsigned long nfs_access_max_cachesize = ULONG_MAX;
+module_param(nfs_access_max_cachesize, ulong, 0644);
+MODULE_PARM_DESC(nfs_access_max_cachesize, "NFS access maximum total cache length");
+
static void nfs_access_free_entry(struct nfs_access_entry *entry)
{
put_rpccred(entry->cred);
@@ -2049,18 +2053,13 @@ static void nfs_access_free_list(struct list_head *head)
}
unsigned long
-nfs_access_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
+nfs_do_access_cache_scan(unsigned int nr_to_scan)
{
LIST_HEAD(head);
struct nfs_inode *nfsi, *next;
struct nfs_access_entry *cache;
- int nr_to_scan = sc->nr_to_scan;
- gfp_t gfp_mask = sc->gfp_mask;
long freed = 0;
- if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
- return SHRINK_STOP;
-
spin_lock(&nfs_access_lru_lock);
list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
struct inode *inode;
@@ -2094,11 +2093,39 @@ remove_lru_entry:
}
unsigned long
+nfs_access_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
+{
+ int nr_to_scan = sc->nr_to_scan;
+ gfp_t gfp_mask = sc->gfp_mask;
+
+ if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
+ return SHRINK_STOP;
+ return nfs_do_access_cache_scan(nr_to_scan);
+}
+
+
+unsigned long
nfs_access_cache_count(struct shrinker *shrink, struct shrink_control *sc)
{
return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries));
}
+static void
+nfs_access_cache_enforce_limit(void)
+{
+ long nr_entries = atomic_long_read(&nfs_access_nr_entries);
+ unsigned long diff;
+ unsigned int nr_to_scan;
+
+ if (nr_entries < 0 || nr_entries <= nfs_access_max_cachesize)
+ return;
+ nr_to_scan = 100;
+ diff = nr_entries - nfs_access_max_cachesize;
+ if (diff < nr_to_scan)
+ nr_to_scan = diff;
+ nfs_do_access_cache_scan(nr_to_scan);
+}
+
static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)
{
struct rb_root *root_node = &nfsi->access_cache;
@@ -2244,6 +2271,7 @@ void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
&nfs_access_lru_list);
spin_unlock(&nfs_access_lru_lock);
}
+ nfs_access_cache_enforce_limit();
}
EXPORT_SYMBOL_GPL(nfs_access_add_cache);
This may be used to limit the number of cached credentials building up inside the access cache. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> --- fs/nfs/dir.c | 40 ++++++++++++++++++++++++++++++++++------ 1 file changed, 34 insertions(+), 6 deletions(-)