From 7f7ab336898f281e58540ef781a8fb375acc32a9 Mon Sep 17 00:00:00 2001 From: Qi Zheng Date: Thu, 15 Jun 2023 11:19:46 +0000 Subject: [PATCH] NFSv4.2: fix wrong shrinker_id 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 Signed-off-by: Trond Myklebust --- fs/nfs/nfs42xattr.c | 79 +++++++++++++++++++++++++-------------------- 1 file changed, 44 insertions(+), 35 deletions(-) diff --git a/fs/nfs/nfs42xattr.c b/fs/nfs/nfs42xattr.c index 76ae11834206..911f634ba3da 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 @@ out4: 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); }