From 016200c37341b62df14ec642b0b30b4b70bc09af Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 30 Jul 2014 08:27:21 -0400 Subject: nfsd: add more granular locking to forget_locks fault injector ...instead of relying on the client_mutex. Signed-off-by: Jeff Layton Signed-off-by: J. Bruce Fields --- fs/nfsd/fault_inject.c | 8 ++- fs/nfsd/nfs4state.c | 132 +++++++++++++++++++++++++++++++++++++++++++++---- fs/nfsd/state.h | 7 ++- 3 files changed, 131 insertions(+), 16 deletions(-) (limited to 'fs/nfsd') diff --git a/fs/nfsd/fault_inject.c b/fs/nfsd/fault_inject.c index 76ecdff37ea2..a444d821d2a5 100644 --- a/fs/nfsd/fault_inject.c +++ b/fs/nfsd/fault_inject.c @@ -140,11 +140,9 @@ static struct nfsd_fault_inject_op inject_ops[] = { }, { .file = "forget_locks", - .get = nfsd_inject_get, - .set_val = nfsd_inject_set, - .set_clnt = nfsd_inject_set_client, - .forget = nfsd_forget_client_locks, - .print = nfsd_print_client_locks, + .get = nfsd_inject_print_locks, + .set_val = nfsd_inject_forget_locks, + .set_clnt = nfsd_inject_forget_client_locks, }, { .file = "forget_openowners", diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index b661294144ba..48ae0a66d512 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -5723,6 +5723,12 @@ nfs4_check_open_reclaim(clientid_t *clid, } #ifdef CONFIG_NFSD_FAULT_INJECTION +static inline void +put_client(struct nfs4_client *clp) +{ + atomic_dec(&clp->cl_refcount); +} + u64 nfsd_inject_print_clients(struct nfsd_fault_inject_op *op) { @@ -5810,6 +5816,22 @@ static void nfsd_print_count(struct nfs4_client *clp, unsigned int count, printk(KERN_INFO "NFS Client: %s has %u %s\n", buf, count, type); } +static void +nfsd_inject_add_lock_to_list(struct nfs4_ol_stateid *lst, + struct list_head *collect) +{ + struct nfs4_client *clp = lst->st_stid.sc_client; + struct nfsd_net *nn = net_generic(current->nsproxy->net_ns, + nfsd_net_id); + + if (!collect) + return; + + lockdep_assert_held(&nn->client_lock); + atomic_inc(&clp->cl_refcount); + list_add(&lst->st_locks, collect); +} + static u64 nfsd_foreach_client_lock(struct nfs4_client *clp, u64 max, struct list_head *collect, void (*func)(struct nfs4_ol_stateid *)) @@ -5819,6 +5841,7 @@ static u64 nfsd_foreach_client_lock(struct nfs4_client *clp, u64 max, struct nfs4_ol_stateid *lst, *lst_next; u64 count = 0; + spin_lock(&clp->cl_lock); list_for_each_entry(oop, &clp->cl_openowners, oo_perclient) { list_for_each_entry_safe(stp, st_next, &oop->oo_owner.so_stateids, st_perstateowner) { @@ -5826,31 +5849,122 @@ static u64 nfsd_foreach_client_lock(struct nfs4_client *clp, u64 max, &stp->st_locks, st_locks) { if (func) { func(lst); - if (collect) - list_add(&lst->st_locks, - collect); + nfsd_inject_add_lock_to_list(lst, + collect); } - if (++count == max) - return count; + ++count; + /* + * Despite the fact that these functions deal + * with 64-bit integers for "count", we must + * ensure that it doesn't blow up the + * clp->cl_refcount. Throw a warning if we + * start to approach INT_MAX here. + */ + WARN_ON_ONCE(count == (INT_MAX / 2)); + if (count == max) + goto out; } } } +out: + spin_unlock(&clp->cl_lock); return count; } -u64 nfsd_forget_client_locks(struct nfs4_client *clp, u64 max) +static u64 +nfsd_collect_client_locks(struct nfs4_client *clp, struct list_head *collect, + u64 max) { - return nfsd_foreach_client_lock(clp, max, NULL, release_lock_stateid); + return nfsd_foreach_client_lock(clp, max, collect, unhash_lock_stateid); } -u64 nfsd_print_client_locks(struct nfs4_client *clp, u64 max) +static u64 +nfsd_print_client_locks(struct nfs4_client *clp) { - u64 count = nfsd_foreach_client_lock(clp, max, NULL, NULL); + u64 count = nfsd_foreach_client_lock(clp, 0, NULL, NULL); nfsd_print_count(clp, count, "locked files"); return count; } +u64 +nfsd_inject_print_locks(struct nfsd_fault_inject_op *op) +{ + struct nfs4_client *clp; + u64 count = 0; + struct nfsd_net *nn = net_generic(current->nsproxy->net_ns, + nfsd_net_id); + + if (!nfsd_netns_ready(nn)) + return 0; + + spin_lock(&nn->client_lock); + list_for_each_entry(clp, &nn->client_lru, cl_lru) + count += nfsd_print_client_locks(clp); + spin_unlock(&nn->client_lock); + + return count; +} + +static void +nfsd_reap_locks(struct list_head *reaplist) +{ + struct nfs4_client *clp; + struct nfs4_ol_stateid *stp, *next; + + list_for_each_entry_safe(stp, next, reaplist, st_locks) { + list_del_init(&stp->st_locks); + clp = stp->st_stid.sc_client; + nfs4_put_stid(&stp->st_stid); + put_client(clp); + } +} + +u64 +nfsd_inject_forget_client_locks(struct nfsd_fault_inject_op *op, + struct sockaddr_storage *addr, size_t addr_size) +{ + unsigned int count = 0; + struct nfs4_client *clp; + struct nfsd_net *nn = net_generic(current->nsproxy->net_ns, + nfsd_net_id); + LIST_HEAD(reaplist); + + if (!nfsd_netns_ready(nn)) + return count; + + spin_lock(&nn->client_lock); + clp = nfsd_find_client(addr, addr_size); + if (clp) + count = nfsd_collect_client_locks(clp, &reaplist, 0); + spin_unlock(&nn->client_lock); + nfsd_reap_locks(&reaplist); + return count; +} + +u64 +nfsd_inject_forget_locks(struct nfsd_fault_inject_op *op, u64 max) +{ + u64 count = 0; + struct nfs4_client *clp; + struct nfsd_net *nn = net_generic(current->nsproxy->net_ns, + nfsd_net_id); + LIST_HEAD(reaplist); + + if (!nfsd_netns_ready(nn)) + return count; + + spin_lock(&nn->client_lock); + list_for_each_entry(clp, &nn->client_lru, cl_lru) { + count += nfsd_collect_client_locks(clp, &reaplist, max - count); + if (max != 0 && count >= max) + break; + } + spin_unlock(&nn->client_lock); + nfsd_reap_locks(&reaplist); + return count; +} + static u64 nfsd_foreach_client_open(struct nfs4_client *clp, u64 max, void (*func)(struct nfs4_openowner *)) { struct nfs4_openowner *oop, *next; diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index eb3b35a74795..028947688d57 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -483,12 +483,15 @@ u64 nfsd_inject_forget_client(struct nfsd_fault_inject_op *, struct sockaddr_storage *, size_t); u64 nfsd_inject_forget_clients(struct nfsd_fault_inject_op *, u64); -u64 nfsd_forget_client_locks(struct nfs4_client*, u64); +u64 nfsd_inject_print_locks(struct nfsd_fault_inject_op *); +u64 nfsd_inject_forget_client_locks(struct nfsd_fault_inject_op *, + struct sockaddr_storage *, size_t); +u64 nfsd_inject_forget_locks(struct nfsd_fault_inject_op *, u64); + u64 nfsd_forget_client_openowners(struct nfs4_client *, u64); u64 nfsd_forget_client_delegations(struct nfs4_client *, u64); u64 nfsd_recall_client_delegations(struct nfs4_client *, u64); -u64 nfsd_print_client_locks(struct nfs4_client *, u64); u64 nfsd_print_client_openowners(struct nfs4_client *, u64); u64 nfsd_print_client_delegations(struct nfs4_client *, u64); #else /* CONFIG_NFSD_FAULT_INJECTION */ -- cgit v1.2.3-55-g7522