This is a note to let you know that I've just added the patch titled
NFSv4.2: fix wrong shrinker_id
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsv4.2-fix-wrong-shrinker_id.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1fecfe6e06fd159b0d6875239e437a51ec82be8e
Author: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Date: Thu Jun 15 11:19:46 2023 +0000
NFSv4.2: fix wrong shrinker_id
[ Upstream commit 7f7ab336898f281e58540ef781a8fb375acc32a9 ]
Currently, the list_lru::shrinker_id corresponding to the nfs4_xattr
shrinkers is wrong:
>>> prog["nfs4_xattr_cache_lru"].shrinker_id
(int)0
>>> prog["nfs4_xattr_entry_lru"].shrinker_id
(int)0
>>> prog["nfs4_xattr_large_entry_lru"].shrinker_id
(int)0
>>> prog["nfs4_xattr_cache_shrinker"].id
(int)18
>>> prog["nfs4_xattr_entry_shrinker"].id
(int)19
>>> prog["nfs4_xattr_large_entry_shrinker"].id
(int)20
This is not what we expect, which will cause these shrinkers
not to be found in shrink_slab_memcg().
We should assign shrinker::id before calling list_lru_init_memcg(),
so that the corresponding list_lru::shrinker_id will be assigned
the correct value like below:
>>> prog["nfs4_xattr_cache_lru"].shrinker_id
(int)16
>>> prog["nfs4_xattr_entry_lru"].shrinker_id
(int)17
>>> prog["nfs4_xattr_large_entry_lru"].shrinker_id
(int)18
>>> prog["nfs4_xattr_cache_shrinker"].id
(int)16
>>> prog["nfs4_xattr_entry_shrinker"].id
(int)17
>>> prog["nfs4_xattr_large_entry_shrinker"].id
(int)18
So just do it.
Fixes: 95ad37f90c33 ("NFSv4.2: add client side xattr caching.")
Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/nfs/nfs42xattr.c b/fs/nfs/nfs42xattr.c
index 76ae118342066..911f634ba3da7 100644
--- a/fs/nfs/nfs42xattr.c
+++ b/fs/nfs/nfs42xattr.c
@@ -991,6 +991,29 @@ static void nfs4_xattr_cache_init_once(void *p)
INIT_LIST_HEAD(&cache->dispose);
}
+static int nfs4_xattr_shrinker_init(struct shrinker *shrinker,
+ struct list_lru *lru, const char *name)
+{
+ int ret = 0;
+
+ ret = register_shrinker(shrinker, name);
+ if (ret)
+ return ret;
+
+ ret = list_lru_init_memcg(lru, shrinker);
+ if (ret)
+ unregister_shrinker(shrinker);
+
+ return ret;
+}
+
+static void nfs4_xattr_shrinker_destroy(struct shrinker *shrinker,
+ struct list_lru *lru)
+{
+ unregister_shrinker(shrinker);
+ list_lru_destroy(lru);
+}
+
int __init nfs4_xattr_cache_init(void)
{
int ret = 0;
@@ -1002,44 +1025,30 @@ int __init nfs4_xattr_cache_init(void)
if (nfs4_xattr_cache_cachep == NULL)
return -ENOMEM;
- ret = list_lru_init_memcg(&nfs4_xattr_large_entry_lru,
- &nfs4_xattr_large_entry_shrinker);
- if (ret)
- goto out4;
-
- ret = list_lru_init_memcg(&nfs4_xattr_entry_lru,
- &nfs4_xattr_entry_shrinker);
- if (ret)
- goto out3;
-
- ret = list_lru_init_memcg(&nfs4_xattr_cache_lru,
- &nfs4_xattr_cache_shrinker);
- if (ret)
- goto out2;
-
- ret = register_shrinker(&nfs4_xattr_cache_shrinker, "nfs-xattr_cache");
+ ret = nfs4_xattr_shrinker_init(&nfs4_xattr_cache_shrinker,
+ &nfs4_xattr_cache_lru,
+ "nfs-xattr_cache");
if (ret)
goto out1;
- ret = register_shrinker(&nfs4_xattr_entry_shrinker, "nfs-xattr_entry");
+ ret = nfs4_xattr_shrinker_init(&nfs4_xattr_entry_shrinker,
+ &nfs4_xattr_entry_lru,
+ "nfs-xattr_entry");
if (ret)
- goto out;
+ goto out2;
- ret = register_shrinker(&nfs4_xattr_large_entry_shrinker,
- "nfs-xattr_large_entry");
+ ret = nfs4_xattr_shrinker_init(&nfs4_xattr_large_entry_shrinker,
+ &nfs4_xattr_large_entry_lru,
+ "nfs-xattr_large_entry");
if (!ret)
return 0;
- unregister_shrinker(&nfs4_xattr_entry_shrinker);
-out:
- unregister_shrinker(&nfs4_xattr_cache_shrinker);
-out1:
- list_lru_destroy(&nfs4_xattr_cache_lru);
+ nfs4_xattr_shrinker_destroy(&nfs4_xattr_entry_shrinker,
+ &nfs4_xattr_entry_lru);
out2:
- list_lru_destroy(&nfs4_xattr_entry_lru);
-out3:
- list_lru_destroy(&nfs4_xattr_large_entry_lru);
-out4:
+ nfs4_xattr_shrinker_destroy(&nfs4_xattr_cache_shrinker,
+ &nfs4_xattr_cache_lru);
+out1:
kmem_cache_destroy(nfs4_xattr_cache_cachep);
return ret;
@@ -1047,11 +1056,11 @@ int __init nfs4_xattr_cache_init(void)
void nfs4_xattr_cache_exit(void)
{
- unregister_shrinker(&nfs4_xattr_large_entry_shrinker);
- unregister_shrinker(&nfs4_xattr_entry_shrinker);
- unregister_shrinker(&nfs4_xattr_cache_shrinker);
- list_lru_destroy(&nfs4_xattr_large_entry_lru);
- list_lru_destroy(&nfs4_xattr_entry_lru);
- list_lru_destroy(&nfs4_xattr_cache_lru);
+ nfs4_xattr_shrinker_destroy(&nfs4_xattr_large_entry_shrinker,
+ &nfs4_xattr_large_entry_lru);
+ nfs4_xattr_shrinker_destroy(&nfs4_xattr_entry_shrinker,
+ &nfs4_xattr_entry_lru);
+ nfs4_xattr_shrinker_destroy(&nfs4_xattr_cache_shrinker,
+ &nfs4_xattr_cache_lru);
kmem_cache_destroy(nfs4_xattr_cache_cachep);
}
