5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Amir Goldstein amir73il@gmail.com
[ Upstream commit e567b98ce9a4b35b63c364d24828a9e5cd7a8179 ]
nfsd stats counters can be updated by concurrent nfsd threads without any protection.
Convert some nfsd_stats and nfsd_net struct members to use percpu counters.
The longest_chain* members of struct nfsd_net remain unprotected.
Signed-off-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/netns.h | 23 +++++++------ fs/nfsd/nfs4proc.c | 2 +- fs/nfsd/nfscache.c | 52 +++++++++++++++++++++--------- fs/nfsd/nfsctl.c | 5 ++- fs/nfsd/nfsfh.c | 2 +- fs/nfsd/stats.c | 77 ++++++++++++++++++++++++++++++++++++-------- fs/nfsd/stats.h | 80 +++++++++++++++++++++++++++++++++++++++------- fs/nfsd/vfs.c | 4 +-- 8 files changed, 192 insertions(+), 53 deletions(-)
diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index 02d3d2f0e6168..a75abeb1e6988 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -10,6 +10,7 @@
#include <net/net_namespace.h> #include <net/netns/generic.h> +#include <linux/percpu_counter.h>
/* Hash tables for nfs4_clientid state */ #define CLIENT_HASH_BITS 4 @@ -21,6 +22,14 @@ struct cld_net; struct nfsd4_client_tracking_ops;
+enum { + /* cache misses due only to checksum comparison failures */ + NFSD_NET_PAYLOAD_MISSES, + /* amount of memory (in bytes) currently consumed by the DRC */ + NFSD_NET_DRC_MEM_USAGE, + NFSD_NET_COUNTERS_NUM +}; + /* * Represents a nfsd "container". With respect to nfsv4 state tracking, the * fields of interest are the *_id_hashtbls and the *_name_tree. These track @@ -149,20 +158,16 @@ struct nfsd_net {
/* * Stats and other tracking of on the duplicate reply cache. - * These fields and the "rc" fields in nfsdstats are modified - * with only the per-bucket cache lock, which isn't really safe - * and should be fixed if we want the statistics to be - * completely accurate. + * The longest_chain* fields are modified with only the per-bucket + * cache lock, which isn't really safe and should be fixed if we want + * these statistics to be completely accurate. */
/* total number of entries */ atomic_t num_drc_entries;
- /* cache misses due only to checksum comparison failures */ - unsigned int payload_misses; - - /* amount of memory (in bytes) currently consumed by the DRC */ - unsigned int drc_mem_usage; + /* Per-netns stats counters */ + struct percpu_counter counter[NFSD_NET_COUNTERS_NUM];
/* longest hash chain seen */ unsigned int longest_chain; diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index a5e1f5c1a4d64..4f64d94909ec1 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -2168,7 +2168,7 @@ nfsd4_proc_null(struct svc_rqst *rqstp) static inline void nfsd4_increment_op_stats(u32 opnum) { if (opnum >= FIRST_NFS4_OP && opnum <= LAST_NFS4_OP) - nfsdstats.nfs4_opcount[opnum]++; + percpu_counter_inc(&nfsdstats.counter[NFSD_STATS_NFS4_OP(opnum)]); }
static const struct nfsd4_operation nfsd4_ops[]; diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c index 80c90fc231a53..96cdf77925f33 100644 --- a/fs/nfsd/nfscache.c +++ b/fs/nfsd/nfscache.c @@ -121,14 +121,14 @@ nfsd_reply_cache_free_locked(struct nfsd_drc_bucket *b, struct svc_cacherep *rp, struct nfsd_net *nn) { if (rp->c_type == RC_REPLBUFF && rp->c_replvec.iov_base) { - nn->drc_mem_usage -= rp->c_replvec.iov_len; + nfsd_stats_drc_mem_usage_sub(nn, rp->c_replvec.iov_len); kfree(rp->c_replvec.iov_base); } if (rp->c_state != RC_UNUSED) { rb_erase(&rp->c_node, &b->rb_head); list_del(&rp->c_lru); atomic_dec(&nn->num_drc_entries); - nn->drc_mem_usage -= sizeof(*rp); + nfsd_stats_drc_mem_usage_sub(nn, sizeof(*rp)); } kmem_cache_free(drc_slab, rp); } @@ -154,6 +154,16 @@ void nfsd_drc_slab_free(void) kmem_cache_destroy(drc_slab); }
+static int nfsd_reply_cache_stats_init(struct nfsd_net *nn) +{ + return nfsd_percpu_counters_init(nn->counter, NFSD_NET_COUNTERS_NUM); +} + +static void nfsd_reply_cache_stats_destroy(struct nfsd_net *nn) +{ + nfsd_percpu_counters_destroy(nn->counter, NFSD_NET_COUNTERS_NUM); +} + int nfsd_reply_cache_init(struct nfsd_net *nn) { unsigned int hashsize; @@ -165,12 +175,16 @@ int nfsd_reply_cache_init(struct nfsd_net *nn) hashsize = nfsd_hashsize(nn->max_drc_entries); nn->maskbits = ilog2(hashsize);
+ status = nfsd_reply_cache_stats_init(nn); + if (status) + goto out_nomem; + nn->nfsd_reply_cache_shrinker.scan_objects = nfsd_reply_cache_scan; nn->nfsd_reply_cache_shrinker.count_objects = nfsd_reply_cache_count; nn->nfsd_reply_cache_shrinker.seeks = 1; status = register_shrinker(&nn->nfsd_reply_cache_shrinker); if (status) - goto out_nomem; + goto out_stats_destroy;
nn->drc_hashtbl = kvzalloc(array_size(hashsize, sizeof(*nn->drc_hashtbl)), GFP_KERNEL); @@ -186,6 +200,8 @@ int nfsd_reply_cache_init(struct nfsd_net *nn) return 0; out_shrinker: unregister_shrinker(&nn->nfsd_reply_cache_shrinker); +out_stats_destroy: + nfsd_reply_cache_stats_destroy(nn); out_nomem: printk(KERN_ERR "nfsd: failed to allocate reply cache\n"); return -ENOMEM; @@ -196,6 +212,7 @@ void nfsd_reply_cache_shutdown(struct nfsd_net *nn) struct svc_cacherep *rp; unsigned int i;
+ nfsd_reply_cache_stats_destroy(nn); unregister_shrinker(&nn->nfsd_reply_cache_shrinker);
for (i = 0; i < nn->drc_hashsize; i++) { @@ -324,7 +341,7 @@ nfsd_cache_key_cmp(const struct svc_cacherep *key, { if (key->c_key.k_xid == rp->c_key.k_xid && key->c_key.k_csum != rp->c_key.k_csum) { - ++nn->payload_misses; + nfsd_stats_payload_misses_inc(nn); trace_nfsd_drc_mismatch(nn, key, rp); }
@@ -407,7 +424,7 @@ int nfsd_cache_lookup(struct svc_rqst *rqstp)
rqstp->rq_cacherep = NULL; if (type == RC_NOCACHE) { - nfsdstats.rcnocache++; + nfsd_stats_rc_nocache_inc(); goto out; }
@@ -429,12 +446,12 @@ int nfsd_cache_lookup(struct svc_rqst *rqstp) goto found_entry; }
- nfsdstats.rcmisses++; + nfsd_stats_rc_misses_inc(); rqstp->rq_cacherep = rp; rp->c_state = RC_INPROG;
atomic_inc(&nn->num_drc_entries); - nn->drc_mem_usage += sizeof(*rp); + nfsd_stats_drc_mem_usage_add(nn, sizeof(*rp));
/* go ahead and prune the cache */ prune_bucket(b, nn); @@ -446,7 +463,7 @@ int nfsd_cache_lookup(struct svc_rqst *rqstp)
found_entry: /* We found a matching entry which is either in progress or done. */ - nfsdstats.rchits++; + nfsd_stats_rc_hits_inc(); rtn = RC_DROPIT;
/* Request being processed */ @@ -548,7 +565,7 @@ void nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp) return; } spin_lock(&b->cache_lock); - nn->drc_mem_usage += bufsize; + nfsd_stats_drc_mem_usage_add(nn, bufsize); lru_put_end(b, rp); rp->c_secure = test_bit(RQ_SECURE, &rqstp->rq_flags); rp->c_type = cachetype; @@ -588,13 +605,18 @@ static int nfsd_reply_cache_stats_show(struct seq_file *m, void *v)
seq_printf(m, "max entries: %u\n", nn->max_drc_entries); seq_printf(m, "num entries: %u\n", - atomic_read(&nn->num_drc_entries)); + atomic_read(&nn->num_drc_entries)); seq_printf(m, "hash buckets: %u\n", 1 << nn->maskbits); - seq_printf(m, "mem usage: %u\n", nn->drc_mem_usage); - seq_printf(m, "cache hits: %u\n", nfsdstats.rchits); - seq_printf(m, "cache misses: %u\n", nfsdstats.rcmisses); - seq_printf(m, "not cached: %u\n", nfsdstats.rcnocache); - seq_printf(m, "payload misses: %u\n", nn->payload_misses); + seq_printf(m, "mem usage: %lld\n", + percpu_counter_sum_positive(&nn->counter[NFSD_NET_DRC_MEM_USAGE])); + seq_printf(m, "cache hits: %lld\n", + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_RC_HITS])); + seq_printf(m, "cache misses: %lld\n", + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_RC_MISSES])); + seq_printf(m, "not cached: %lld\n", + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_RC_NOCACHE])); + seq_printf(m, "payload misses: %lld\n", + percpu_counter_sum_positive(&nn->counter[NFSD_NET_PAYLOAD_MISSES])); seq_printf(m, "longest chain len: %u\n", nn->longest_chain); seq_printf(m, "cachesize at longest: %u\n", nn->longest_chain_cachesize); return 0; diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index c4b11560ac1b6..7f85c171f83aa 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1522,7 +1522,9 @@ static int __init init_nfsd(void) retval = nfsd4_init_pnfs(); if (retval) goto out_free_slabs; - nfsd_stat_init(); /* Statistics */ + retval = nfsd_stat_init(); /* Statistics */ + if (retval) + goto out_free_pnfs; retval = nfsd_drc_slab_create(); if (retval) goto out_free_stat; @@ -1552,6 +1554,7 @@ static int __init init_nfsd(void) nfsd_drc_slab_free(); out_free_stat: nfsd_stat_shutdown(); +out_free_pnfs: nfsd4_exit_pnfs(); out_free_slabs: nfsd4_free_slabs(); diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index 66f2ef67792a7..9e31b2b5c6d26 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -422,7 +422,7 @@ fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access) } out: if (error == nfserr_stale) - nfsdstats.fh_stale++; + nfsd_stats_fh_stale_inc(); return error; }
diff --git a/fs/nfsd/stats.c b/fs/nfsd/stats.c index e928e224205ac..1d3b881e73821 100644 --- a/fs/nfsd/stats.c +++ b/fs/nfsd/stats.c @@ -36,13 +36,13 @@ static int nfsd_proc_show(struct seq_file *seq, void *v) { int i;
- seq_printf(seq, "rc %u %u %u\nfh %u 0 0 0 0\nio %u %u\n", - nfsdstats.rchits, - nfsdstats.rcmisses, - nfsdstats.rcnocache, - nfsdstats.fh_stale, - nfsdstats.io_read, - nfsdstats.io_write); + seq_printf(seq, "rc %lld %lld %lld\nfh %lld 0 0 0 0\nio %lld %lld\n", + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_RC_HITS]), + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_RC_MISSES]), + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_RC_NOCACHE]), + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_FH_STALE]), + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_IO_READ]), + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_IO_WRITE]));
/* thread usage: */ seq_printf(seq, "th %u 0", nfsdstats.th_cnt); @@ -61,8 +61,10 @@ static int nfsd_proc_show(struct seq_file *seq, void *v) /* Show count for individual nfsv4 operations */ /* Writing operation numbers 0 1 2 also for maintaining uniformity */ seq_printf(seq,"proc4ops %u", LAST_NFS4_OP + 1); - for (i = 0; i <= LAST_NFS4_OP; i++) - seq_printf(seq, " %u", nfsdstats.nfs4_opcount[i]); + for (i = 0; i <= LAST_NFS4_OP; i++) { + seq_printf(seq, " %lld", + percpu_counter_sum_positive(&nfsdstats.counter[NFSD_STATS_NFS4_OP(i)])); + }
seq_putc(seq, '\n'); #endif @@ -82,14 +84,63 @@ static const struct proc_ops nfsd_proc_ops = { .proc_release = single_release, };
-void -nfsd_stat_init(void) +int nfsd_percpu_counters_init(struct percpu_counter counters[], int num) { + int i, err = 0; + + for (i = 0; !err && i < num; i++) + err = percpu_counter_init(&counters[i], 0, GFP_KERNEL); + + if (!err) + return 0; + + for (; i > 0; i--) + percpu_counter_destroy(&counters[i-1]); + + return err; +} + +void nfsd_percpu_counters_reset(struct percpu_counter counters[], int num) +{ + int i; + + for (i = 0; i < num; i++) + percpu_counter_set(&counters[i], 0); +} + +void nfsd_percpu_counters_destroy(struct percpu_counter counters[], int num) +{ + int i; + + for (i = 0; i < num; i++) + percpu_counter_destroy(&counters[i]); +} + +static int nfsd_stat_counters_init(void) +{ + return nfsd_percpu_counters_init(nfsdstats.counter, NFSD_STATS_COUNTERS_NUM); +} + +static void nfsd_stat_counters_destroy(void) +{ + nfsd_percpu_counters_destroy(nfsdstats.counter, NFSD_STATS_COUNTERS_NUM); +} + +int nfsd_stat_init(void) +{ + int err; + + err = nfsd_stat_counters_init(); + if (err) + return err; + svc_proc_register(&init_net, &nfsd_svcstats, &nfsd_proc_ops); + + return 0; }
-void -nfsd_stat_shutdown(void) +void nfsd_stat_shutdown(void) { + nfsd_stat_counters_destroy(); svc_proc_unregister(&init_net, "nfsd"); } diff --git a/fs/nfsd/stats.h b/fs/nfsd/stats.h index 5e3cdf21556a1..87c3150c200f0 100644 --- a/fs/nfsd/stats.h +++ b/fs/nfsd/stats.h @@ -8,27 +8,85 @@ #define _NFSD_STATS_H
#include <uapi/linux/nfsd/stats.h> +#include <linux/percpu_counter.h>
-struct nfsd_stats { - unsigned int rchits; /* repcache hits */ - unsigned int rcmisses; /* repcache hits */ - unsigned int rcnocache; /* uncached reqs */ - unsigned int fh_stale; /* FH stale error */ - unsigned int io_read; /* bytes returned to read requests */ - unsigned int io_write; /* bytes passed in write requests */ - unsigned int th_cnt; /* number of available threads */ +enum { + NFSD_STATS_RC_HITS, /* repcache hits */ + NFSD_STATS_RC_MISSES, /* repcache misses */ + NFSD_STATS_RC_NOCACHE, /* uncached reqs */ + NFSD_STATS_FH_STALE, /* FH stale error */ + NFSD_STATS_IO_READ, /* bytes returned to read requests */ + NFSD_STATS_IO_WRITE, /* bytes passed in write requests */ #ifdef CONFIG_NFSD_V4 - unsigned int nfs4_opcount[LAST_NFS4_OP + 1]; /* count of individual nfsv4 operations */ + NFSD_STATS_FIRST_NFS4_OP, /* count of individual nfsv4 operations */ + NFSD_STATS_LAST_NFS4_OP = NFSD_STATS_FIRST_NFS4_OP + LAST_NFS4_OP, +#define NFSD_STATS_NFS4_OP(op) (NFSD_STATS_FIRST_NFS4_OP + (op)) #endif + NFSD_STATS_COUNTERS_NUM +}; + +struct nfsd_stats { + struct percpu_counter counter[NFSD_STATS_COUNTERS_NUM];
+ /* Protected by nfsd_mutex */ + unsigned int th_cnt; /* number of available threads */ };
extern struct nfsd_stats nfsdstats; + extern struct svc_stat nfsd_svcstats;
-void nfsd_stat_init(void); -void nfsd_stat_shutdown(void); +int nfsd_percpu_counters_init(struct percpu_counter counters[], int num); +void nfsd_percpu_counters_reset(struct percpu_counter counters[], int num); +void nfsd_percpu_counters_destroy(struct percpu_counter counters[], int num); +int nfsd_stat_init(void); +void nfsd_stat_shutdown(void); + +static inline void nfsd_stats_rc_hits_inc(void) +{ + percpu_counter_inc(&nfsdstats.counter[NFSD_STATS_RC_HITS]); +} + +static inline void nfsd_stats_rc_misses_inc(void) +{ + percpu_counter_inc(&nfsdstats.counter[NFSD_STATS_RC_MISSES]); +} + +static inline void nfsd_stats_rc_nocache_inc(void) +{ + percpu_counter_inc(&nfsdstats.counter[NFSD_STATS_RC_NOCACHE]); +} + +static inline void nfsd_stats_fh_stale_inc(void) +{ + percpu_counter_inc(&nfsdstats.counter[NFSD_STATS_FH_STALE]); +} + +static inline void nfsd_stats_io_read_add(s64 amount) +{ + percpu_counter_add(&nfsdstats.counter[NFSD_STATS_IO_READ], amount); +} + +static inline void nfsd_stats_io_write_add(s64 amount) +{ + percpu_counter_add(&nfsdstats.counter[NFSD_STATS_IO_WRITE], amount); +} + +static inline void nfsd_stats_payload_misses_inc(struct nfsd_net *nn) +{ + percpu_counter_inc(&nn->counter[NFSD_NET_PAYLOAD_MISSES]); +} + +static inline void nfsd_stats_drc_mem_usage_add(struct nfsd_net *nn, s64 amount) +{ + percpu_counter_add(&nn->counter[NFSD_NET_DRC_MEM_USAGE], amount); +} + +static inline void nfsd_stats_drc_mem_usage_sub(struct nfsd_net *nn, s64 amount) +{ + percpu_counter_sub(&nn->counter[NFSD_NET_DRC_MEM_USAGE], amount); +}
#endif /* _NFSD_STATS_H */ diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index a515cbd0a7d8f..1b44d8f985be9 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -897,7 +897,7 @@ static __be32 nfsd_finish_read(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned long *count, u32 *eof, ssize_t host_err) { if (host_err >= 0) { - nfsdstats.io_read += host_err; + nfsd_stats_io_read_add(host_err); *eof = nfsd_eof_on_read(file, offset, host_err, *count); *count = host_err; fsnotify_access(file); @@ -1050,7 +1050,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, goto out_nfserr; } *cnt = host_err; - nfsdstats.io_write += *cnt; + nfsd_stats_io_write_add(*cnt); fsnotify_modify(file); host_err = filemap_check_wb_err(file->f_mapping, since); if (host_err < 0)