From f5c2187cfef628784d8a09b6d0f77888246d0c0f Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 25 Jun 2007 17:11:20 -0400 Subject: SUNRPC: Convert the credential garbage collector into a shrinker callback Signed-off-by: Trond Myklebust --- net/sunrpc/auth.c | 63 ++++++++++++++++++++++++++++++------------ net/sunrpc/auth_gss/auth_gss.c | 3 +- net/sunrpc/auth_unix.c | 6 +--- net/sunrpc/sunrpc_syms.c | 3 +- 4 files changed, 49 insertions(+), 26 deletions(-) (limited to 'net/sunrpc') diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index cf1198d10ee9..81f4c776c558 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -26,6 +26,7 @@ static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = { }; static LIST_HEAD(cred_unused); +static unsigned long number_cred_unused; static u32 pseudoflavor_to_flavor(u32 flavor) { @@ -136,7 +137,7 @@ rpcauth_unhash_cred(struct rpc_cred *cred) * Initialize RPC credential cache */ int -rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire) +rpcauth_init_credcache(struct rpc_auth *auth) { struct rpc_cred_cache *new; int i; @@ -147,8 +148,6 @@ rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire) for (i = 0; i < RPC_CREDCACHE_NR; i++) INIT_HLIST_HEAD(&new->hashtable[i]); spin_lock_init(&new->lock); - new->expire = expire; - new->nextgc = jiffies + (expire >> 1); auth->au_credcache = new; return 0; } @@ -187,7 +186,11 @@ rpcauth_clear_credcache(struct rpc_cred_cache *cache) while (!hlist_empty(head)) { cred = hlist_entry(head->first, struct rpc_cred, cr_hash); get_rpccred(cred); - list_move_tail(&cred->cr_lru, &free); + if (!list_empty(&cred->cr_lru)) { + list_del(&cred->cr_lru); + number_cred_unused--; + } + list_add_tail(&cred->cr_lru, &free); rpcauth_unhash_cred_locked(cred); } } @@ -214,18 +217,16 @@ rpcauth_destroy_credcache(struct rpc_auth *auth) /* * Remove stale credentials. Avoid sleeping inside the loop. */ -static void -rpcauth_prune_expired(struct list_head *free) +static int +rpcauth_prune_expired(struct list_head *free, int nr_to_scan) { spinlock_t *cache_lock; struct rpc_cred *cred; while (!list_empty(&cred_unused)) { cred = list_entry(cred_unused.next, struct rpc_cred, cr_lru); - if (time_after(jiffies, cred->cr_expire + - cred->cr_auth->au_credcache->expire)) - break; list_del_init(&cred->cr_lru); + number_cred_unused--; if (atomic_read(&cred->cr_count) != 0) continue; cache_lock = &cred->cr_auth->au_credcache->lock; @@ -234,23 +235,32 @@ rpcauth_prune_expired(struct list_head *free) get_rpccred(cred); list_add_tail(&cred->cr_lru, free); rpcauth_unhash_cred_locked(cred); + nr_to_scan--; } spin_unlock(cache_lock); + if (nr_to_scan == 0) + break; } + return nr_to_scan; } /* - * Run garbage collector. + * Run memory cache shrinker. */ -static void -rpcauth_gc_credcache(struct rpc_cred_cache *cache, struct list_head *free) +static int +rpcauth_cache_shrinker(int nr_to_scan, gfp_t gfp_mask) { - if (list_empty(&cred_unused) || time_before(jiffies, cache->nextgc)) - return; + LIST_HEAD(free); + int res; + + if (list_empty(&cred_unused)) + return 0; spin_lock(&rpc_credcache_lock); - cache->nextgc = jiffies + cache->expire; - rpcauth_prune_expired(free); + nr_to_scan = rpcauth_prune_expired(&free, nr_to_scan); + res = (number_cred_unused / 100) * sysctl_vfs_cache_pressure; spin_unlock(&rpc_credcache_lock); + rpcauth_destroy_credlist(&free); + return res; } /* @@ -318,7 +328,6 @@ found: cred = ERR_PTR(res); } } - rpcauth_gc_credcache(cache, &free); rpcauth_destroy_credlist(&free); out: return cred; @@ -408,13 +417,16 @@ put_rpccred(struct rpc_cred *cred) need_lock: if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock)) return; - if (!list_empty(&cred->cr_lru)) + if (!list_empty(&cred->cr_lru)) { + number_cred_unused--; list_del_init(&cred->cr_lru); + } if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) rpcauth_unhash_cred(cred); else if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) { cred->cr_expire = jiffies; list_add_tail(&cred->cr_lru, &cred_unused); + number_cred_unused++; spin_unlock(&rpc_credcache_lock); return; } @@ -520,3 +532,18 @@ rpcauth_uptodatecred(struct rpc_task *task) return cred == NULL || test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0; } + + +static struct shrinker *rpc_cred_shrinker; + +void __init rpcauth_init_module(void) +{ + rpc_init_authunix(); + rpc_cred_shrinker = set_shrinker(DEFAULT_SEEKS, rpcauth_cache_shrinker); +} + +void __exit rpcauth_remove_module(void) +{ + if (rpc_cred_shrinker != NULL) + remove_shrinker(rpc_cred_shrinker); +} diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 068fa6dfb64e..8653a92144ae 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -64,7 +64,6 @@ static const struct rpc_credops gss_credops; #define NFS_NGROUPS 16 -#define GSS_CRED_EXPIRE (60 * HZ) /* XXX: reasonable? */ #define GSS_CRED_SLACK 1024 /* XXX: unused */ /* length of a krb5 verifier (48), plus data added before arguments when * using integrity (two 4-byte integers): */ @@ -643,7 +642,7 @@ gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) goto err_put_mech; } - err = rpcauth_init_credcache(auth, GSS_CRED_EXPIRE); + err = rpcauth_init_credcache(auth); if (err) goto err_unlink_pipe; diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c index 205878a3caa5..d9c50d810d15 100644 --- a/net/sunrpc/auth_unix.c +++ b/net/sunrpc/auth_unix.c @@ -21,8 +21,6 @@ struct unx_cred { }; #define uc_uid uc_base.cr_uid -#define UNX_CRED_EXPIRE (60 * HZ) - #define UNX_WRITESLACK (21 + (UNX_MAXNODENAME >> 2)) #ifdef RPC_DEBUG @@ -38,8 +36,7 @@ unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) { dprintk("RPC: creating UNIX authenticator for client %p\n", clnt); - if (atomic_inc_return(&unix_auth.au_count) == 1) - unix_cred_cache.nextgc = jiffies + (unix_cred_cache.expire >> 1); + atomic_inc(&unix_auth.au_count); return &unix_auth; } @@ -232,7 +229,6 @@ const struct rpc_authops authunix_ops = { static struct rpc_cred_cache unix_cred_cache = { - .expire = UNX_CRED_EXPIRE, }; static diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c index 018065fca84b..384c4ad5ab86 100644 --- a/net/sunrpc/sunrpc_syms.c +++ b/net/sunrpc/sunrpc_syms.c @@ -152,7 +152,7 @@ init_sunrpc(void) cache_register(&ip_map_cache); cache_register(&unix_gid_cache); init_socket_xprt(); - rpc_init_authunix(); + rpcauth_init_module(); out: return err; } @@ -160,6 +160,7 @@ out: static void __exit cleanup_sunrpc(void) { + rpcauth_remove_module(); cleanup_socket_xprt(); unregister_rpc_pipefs(); rpc_destroy_mempool(); -- cgit v1.2.3