diff options
| -rw-r--r-- | fs/nfsd/filecache.c | 265 | ||||
| -rw-r--r-- | fs/nfsd/trace.h | 63 |
2 files changed, 179 insertions, 149 deletions
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index a5ae5b4620d0..aed3cb6bf865 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -62,7 +62,6 @@ static struct nfsd_fcache_bucket *nfsd_file_hashtbl; static struct list_lru nfsd_file_lru; static unsigned long nfsd_file_flags; static struct fsnotify_group *nfsd_file_fsnotify_group; -static atomic_long_t nfsd_filecache_count; static struct delayed_work nfsd_filecache_laundrette; static struct rhashtable nfsd_file_rhash_tbl ____cacheline_aligned_in_smp; @@ -198,7 +197,7 @@ static const struct rhashtable_params nfsd_file_rhash_params = { static void nfsd_file_schedule_laundrette(void) { - if ((atomic_long_read(&nfsd_filecache_count) == 0) || + if ((atomic_read(&nfsd_file_rhash_tbl.nelems) == 0) || test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 0) return; @@ -298,7 +297,7 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf) } static struct nfsd_file * -nfsd_file_alloc(struct inode *inode, unsigned int may, struct net *net) +nfsd_file_alloc(struct nfsd_file_lookup_key *key, unsigned int may) { struct nfsd_file *nf; @@ -309,11 +308,14 @@ nfsd_file_alloc(struct inode *inode, unsigned int may, struct net *net) nf->nf_birthtime = ktime_get(); nf->nf_file = NULL; nf->nf_cred = get_current_cred(); - nf->nf_net = net; + nf->nf_net = key->net; nf->nf_flags = 0; - nf->nf_inode = inode; - refcount_set(&nf->nf_ref, 1); - nf->nf_may = may & NFSD_FILE_MAY_MASK; + __set_bit(NFSD_FILE_HASHED, &nf->nf_flags); + __set_bit(NFSD_FILE_PENDING, &nf->nf_flags); + nf->nf_inode = key->inode; + /* nf_ref is pre-incremented for hash table */ + refcount_set(&nf->nf_ref, 2); + nf->nf_may = key->need; nf->nf_mark = NULL; trace_nfsd_file_alloc(nf); } @@ -399,40 +401,21 @@ static void nfsd_file_lru_remove(struct nfsd_file *nf) } static void -nfsd_file_do_unhash(struct nfsd_file *nf) +nfsd_file_hash_remove(struct nfsd_file *nf) { - struct inode *inode = nf->nf_inode; - unsigned int hashval = (unsigned int)hash_long(inode->i_ino, - NFSD_FILE_HASH_BITS); - - lockdep_assert_held(&nfsd_file_hashtbl[hashval].nfb_lock); - trace_nfsd_file_unhash(nf); if (nfsd_file_check_write_error(nf)) nfsd_reset_write_verifier(net_generic(nf->nf_net, nfsd_net_id)); - --nfsd_file_hashtbl[hashval].nfb_count; - hlist_del_rcu(&nf->nf_node); - atomic_long_dec(&nfsd_filecache_count); -} - -static void -nfsd_file_hash_remove(struct nfsd_file *nf) -{ - struct inode *inode = nf->nf_inode; - unsigned int hashval = (unsigned int)hash_long(inode->i_ino, - NFSD_FILE_HASH_BITS); - - spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock); - nfsd_file_do_unhash(nf); - spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock); + rhashtable_remove_fast(&nfsd_file_rhash_tbl, &nf->nf_rhash, + nfsd_file_rhash_params); } static bool nfsd_file_unhash(struct nfsd_file *nf) { if (test_and_clear_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { - nfsd_file_do_unhash(nf); + nfsd_file_hash_remove(nf); return true; } return false; @@ -442,9 +425,9 @@ nfsd_file_unhash(struct nfsd_file *nf) * Return true if the file was unhashed. */ static bool -nfsd_file_unhash_and_release_locked(struct nfsd_file *nf, struct list_head *dispose) +nfsd_file_unhash_and_dispose(struct nfsd_file *nf, struct list_head *dispose) { - trace_nfsd_file_unhash_and_release_locked(nf); + trace_nfsd_file_unhash_and_dispose(nf); if (!nfsd_file_unhash(nf)) return false; /* keep final reference for nfsd_file_lru_dispose */ @@ -703,20 +686,23 @@ static struct shrinker nfsd_file_shrinker = { static unsigned int __nfsd_file_close_inode(struct inode *inode, struct list_head *dispose) { - unsigned int hashval = (unsigned int)hash_long(inode->i_ino, - NFSD_FILE_HASH_BITS); - unsigned int count = 0; - struct nfsd_file *nf; - struct hlist_node *tmp; - - spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock); - hlist_for_each_entry_safe(nf, tmp, &nfsd_file_hashtbl[hashval].nfb_head, nf_node) { - if (inode == nf->nf_inode) { - nfsd_file_unhash_and_release_locked(nf, dispose); - count++; - } - } - spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock); + struct nfsd_file_lookup_key key = { + .type = NFSD_FILE_KEY_INODE, + .inode = inode, + }; + unsigned int count = 0; + struct nfsd_file *nf; + + rcu_read_lock(); + do { + nf = rhashtable_lookup(&nfsd_file_rhash_tbl, &key, + nfsd_file_rhash_params); + if (!nf) + break; + nfsd_file_unhash_and_dispose(nf, dispose); + count++; + } while (1); + rcu_read_unlock(); return count; } @@ -924,30 +910,35 @@ out_err: static void __nfsd_file_cache_purge(struct net *net) { - unsigned int i; - struct nfsd_file *nf; - struct hlist_node *next; + struct rhashtable_iter iter; + struct nfsd_file *nf; LIST_HEAD(dispose); bool del; - for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) { - struct nfsd_fcache_bucket *nfb = &nfsd_file_hashtbl[i]; + rhashtable_walk_enter(&nfsd_file_rhash_tbl, &iter); + do { + rhashtable_walk_start(&iter); - spin_lock(&nfb->nfb_lock); - hlist_for_each_entry_safe(nf, next, &nfb->nfb_head, nf_node) { + nf = rhashtable_walk_next(&iter); + while (!IS_ERR_OR_NULL(nf)) { if (net && nf->nf_net != net) continue; - del = nfsd_file_unhash_and_release_locked(nf, &dispose); + del = nfsd_file_unhash_and_dispose(nf, &dispose); /* * Deadlock detected! Something marked this entry as * unhased, but hasn't removed it from the hash list. */ WARN_ON_ONCE(!del); + + nf = rhashtable_walk_next(&iter); } - spin_unlock(&nfb->nfb_lock); - nfsd_file_dispose_list(&dispose); - } + + rhashtable_walk_stop(&iter); + } while (nf == ERR_PTR(-EAGAIN)); + rhashtable_walk_exit(&iter); + + nfsd_file_dispose_list(&dispose); } static struct nfsd_fcache_disposal * @@ -1052,56 +1043,29 @@ nfsd_file_cache_shutdown(void) } } -static struct nfsd_file * -nfsd_file_find_locked(struct inode *inode, unsigned int may_flags, - unsigned int hashval, struct net *net) -{ - struct nfsd_file *nf; - unsigned char need = may_flags & NFSD_FILE_MAY_MASK; - - hlist_for_each_entry_rcu(nf, &nfsd_file_hashtbl[hashval].nfb_head, - nf_node, lockdep_is_held(&nfsd_file_hashtbl[hashval].nfb_lock)) { - if (nf->nf_may != need) - continue; - if (nf->nf_inode != inode) - continue; - if (nf->nf_net != net) - continue; - if (!nfsd_match_cred(nf->nf_cred, current_cred())) - continue; - if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) - continue; - if (nfsd_file_get(nf) != NULL) - return nf; - } - return NULL; -} - /** - * nfsd_file_is_cached - are there any cached open files for this fh? - * @inode: inode of the file to check + * nfsd_file_is_cached - are there any cached open files for this inode? + * @inode: inode to check + * + * The lookup matches inodes in all net namespaces and is atomic wrt + * nfsd_file_acquire(). * - * Scan the hashtable for open files that match this fh. Returns true if there - * are any, and false if not. + * Return values: + * %true: filecache contains at least one file matching this inode + * %false: filecache contains no files matching this inode */ bool nfsd_file_is_cached(struct inode *inode) { - bool ret = false; - struct nfsd_file *nf; - unsigned int hashval; - - hashval = (unsigned int)hash_long(inode->i_ino, NFSD_FILE_HASH_BITS); - - rcu_read_lock(); - hlist_for_each_entry_rcu(nf, &nfsd_file_hashtbl[hashval].nfb_head, - nf_node) { - if (inode == nf->nf_inode) { - ret = true; - break; - } - } - rcu_read_unlock(); + struct nfsd_file_lookup_key key = { + .type = NFSD_FILE_KEY_INODE, + .inode = inode, + }; + bool ret = false; + + if (rhashtable_lookup_fast(&nfsd_file_rhash_tbl, &key, + nfsd_file_rhash_params) != NULL) + ret = true; trace_nfsd_file_is_cached(inode, (int)ret); return ret; } @@ -1110,39 +1074,51 @@ static __be32 nfsd_do_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct nfsd_file **pnf, bool open) { - __be32 status; - struct net *net = SVC_NET(rqstp); + struct nfsd_file_lookup_key key = { + .type = NFSD_FILE_KEY_FULL, + .need = may_flags & NFSD_FILE_MAY_MASK, + .net = SVC_NET(rqstp), + }; struct nfsd_file *nf, *new; - struct inode *inode; - unsigned int hashval; bool retry = true; + __be32 status; - /* FIXME: skip this if fh_dentry is already set? */ status = fh_verify(rqstp, fhp, S_IFREG, may_flags|NFSD_MAY_OWNER_OVERRIDE); if (status != nfs_ok) return status; + key.inode = d_inode(fhp->fh_dentry); + key.cred = get_current_cred(); - inode = d_inode(fhp->fh_dentry); - hashval = (unsigned int)hash_long(inode->i_ino, NFSD_FILE_HASH_BITS); retry: - rcu_read_lock(); - nf = nfsd_file_find_locked(inode, may_flags, hashval, net); - rcu_read_unlock(); + /* Avoid allocation if the item is already in cache */ + nf = rhashtable_lookup_fast(&nfsd_file_rhash_tbl, &key, + nfsd_file_rhash_params); + if (nf) + nf = nfsd_file_get(nf); if (nf) goto wait_for_construction; - new = nfsd_file_alloc(inode, may_flags, net); + new = nfsd_file_alloc(&key, may_flags); if (!new) { status = nfserr_jukebox; goto out_status; } - spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock); - nf = nfsd_file_find_locked(inode, may_flags, hashval, net); - if (nf == NULL) + nf = rhashtable_lookup_get_insert_key(&nfsd_file_rhash_tbl, + &key, &new->nf_rhash, + nfsd_file_rhash_params); + if (!nf) { + nf = new; + goto open_file; + } + if (IS_ERR(nf)) + goto insert_err; + nf = nfsd_file_get(nf); + if (nf == NULL) { + nf = new; goto open_file; - spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock); + } nfsd_file_slab_free(&new->nf_rcu); wait_for_construction: @@ -1150,6 +1126,7 @@ wait_for_construction: /* Did construction of this file fail? */ if (!test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { + trace_nfsd_file_cons_err(rqstp, key.inode, may_flags, nf); if (!retry) { status = nfserr_jukebox; goto out; @@ -1174,22 +1151,11 @@ out: } out_status: - trace_nfsd_file_acquire(rqstp, inode, may_flags, nf, status); + put_cred(key.cred); + trace_nfsd_file_acquire(rqstp, key.inode, may_flags, nf, status); return status; open_file: - nf = new; - /* Take reference for the hashtable */ - refcount_inc(&nf->nf_ref); - __set_bit(NFSD_FILE_HASHED, &nf->nf_flags); - __set_bit(NFSD_FILE_PENDING, &nf->nf_flags); - hlist_add_head_rcu(&nf->nf_node, &nfsd_file_hashtbl[hashval].nfb_head); - ++nfsd_file_hashtbl[hashval].nfb_count; - nfsd_file_hashtbl[hashval].nfb_maxcount = max(nfsd_file_hashtbl[hashval].nfb_maxcount, - nfsd_file_hashtbl[hashval].nfb_count); - spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock); - atomic_long_inc(&nfsd_filecache_count); - nf->nf_mark = nfsd_file_mark_find_or_create(nf); if (nf->nf_mark) { if (open) { @@ -1204,19 +1170,20 @@ open_file: * If construction failed, or we raced with a call to unlink() * then unhash. */ - if (status != nfs_ok || inode->i_nlink == 0) { - bool do_free; - nfsd_file_lru_remove(nf); - spin_lock(&nfsd_file_hashtbl[hashval].nfb_lock); - do_free = nfsd_file_unhash(nf); - spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock); - if (do_free) + if (status != nfs_ok || key.inode->i_nlink == 0) + if (nfsd_file_unhash(nf)) nfsd_file_put_noref(nf); - } clear_bit_unlock(NFSD_FILE_PENDING, &nf->nf_flags); smp_mb__after_atomic(); wake_up_bit(&nf->nf_flags, NFSD_FILE_PENDING); goto out; + +insert_err: + nfsd_file_slab_free(&new->nf_rcu); + trace_nfsd_file_insert_err(rqstp, key.inode, may_flags, PTR_ERR(nf)); + nf = NULL; + status = nfserr_jukebox; + goto out_status; } /** @@ -1262,21 +1229,23 @@ static int nfsd_file_cache_stats_show(struct seq_file *m, void *v) { unsigned long releases = 0, pages_flushed = 0, evictions = 0; unsigned long hits = 0, acquisitions = 0; - unsigned int i, count = 0, longest = 0; + unsigned int i, count = 0, buckets = 0; unsigned long lru = 0, total_age = 0; - /* - * No need for spinlocks here since we're not terribly interested in - * accuracy. We do take the nfsd_mutex simply to ensure that we - * don't end up racing with server shutdown - */ + /* Serialize with server shutdown */ mutex_lock(&nfsd_mutex); if (test_bit(NFSD_FILE_CACHE_UP, &nfsd_file_flags) == 1) { - for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) { - count += nfsd_file_hashtbl[i].nfb_count; - longest = max(longest, nfsd_file_hashtbl[i].nfb_count); - } + struct bucket_table *tbl; + struct rhashtable *ht; + lru = list_lru_count(&nfsd_file_lru); + + rcu_read_lock(); + ht = &nfsd_file_rhash_tbl; + count = atomic_read(&ht->nelems); + tbl = rht_dereference_rcu(ht->tbl, ht); + buckets = tbl->size; + rcu_read_unlock(); } mutex_unlock(&nfsd_mutex); @@ -1290,7 +1259,7 @@ static int nfsd_file_cache_stats_show(struct seq_file *m, void *v) } seq_printf(m, "total entries: %u\n", count); - seq_printf(m, "longest chain: %u\n", longest); + seq_printf(m, "hash buckets: %u\n", buckets); seq_printf(m, "lru entries: %lu\n", lru); seq_printf(m, "cache hits: %lu\n", hits); seq_printf(m, "acquisitions: %lu\n", acquisitions); diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h index 79bf985bfc7d..5d634361debf 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -778,7 +778,7 @@ DEFINE_NFSD_FILE_EVENT(nfsd_file_alloc); DEFINE_NFSD_FILE_EVENT(nfsd_file_put_final); DEFINE_NFSD_FILE_EVENT(nfsd_file_unhash); DEFINE_NFSD_FILE_EVENT(nfsd_file_put); -DEFINE_NFSD_FILE_EVENT(nfsd_file_unhash_and_release_locked); +DEFINE_NFSD_FILE_EVENT(nfsd_file_unhash_and_dispose); TRACE_EVENT(nfsd_file_acquire, TP_PROTO( @@ -821,6 +821,67 @@ TRACE_EVENT(nfsd_file_acquire, __entry->nf_file, __entry->status) ); +TRACE_EVENT(nfsd_file_insert_err, + TP_PROTO( + const struct svc_rqst *rqstp, + const struct inode *inode, + unsigned int may_flags, + long error + ), + TP_ARGS(rqstp, inode, may_flags, error), + TP_STRUCT__entry( + __field(u32, xid) + __field(const void *, inode) + __field(unsigned long, may_flags) + __field(long, error) + ), + TP_fast_assign( + __entry->xid = be32_to_cpu(rqstp->rq_xid); + __entry->inode = inode; + __entry->may_flags = may_flags; + __entry->error = error; + ), + TP_printk("xid=0x%x inode=%p may_flags=%s error=%ld", + __entry->xid, __entry->inode, + show_nfsd_may_flags(__entry->may_flags), + __entry->error + ) +); + +TRACE_EVENT(nfsd_file_cons_err, + TP_PROTO( + const struct svc_rqst *rqstp, + const struct inode *inode, + unsigned int may_flags, + const struct nfsd_file *nf + ), + TP_ARGS(rqstp, inode, may_flags, nf), + TP_STRUCT__entry( + __field(u32, xid) + __field(const void *, inode) + __field(unsigned long, may_flags) + __field(unsigned int, nf_ref) + __field(unsigned long, nf_flags) + __field(unsigned long, nf_may) + __field(const void *, nf_file) + ), + TP_fast_assign( + __entry->xid = be32_to_cpu(rqstp->rq_xid); + __entry->inode = inode; + __entry->may_flags = may_flags; + __entry->nf_ref = refcount_read(&nf->nf_ref); + __entry->nf_flags = nf->nf_flags; + __entry->nf_may = nf->nf_may; + __entry->nf_file = nf->nf_file; + ), + TP_printk("xid=0x%x inode=%p may_flags=%s ref=%u nf_flags=%s nf_may=%s nf_file=%p", + __entry->xid, __entry->inode, + show_nfsd_may_flags(__entry->may_flags), __entry->nf_ref, + show_nf_flags(__entry->nf_flags), + show_nfsd_may_flags(__entry->nf_may), __entry->nf_file + ) +); + TRACE_EVENT(nfsd_file_open, TP_PROTO(struct nfsd_file *nf, __be32 status), TP_ARGS(nf, status), |