diff options
author | NeilBrown <neilb@suse.de> | 2023-12-15 11:56:32 +1100 |
---|---|---|
committer | Chuck Lever <chuck.lever@oracle.com> | 2024-01-07 17:54:33 -0500 |
commit | 7b207ccd983350a5dedd132b57c666186dd02a7c (patch) | |
tree | c953afe0aee7eb0e2608ac61c67dfda73c480e23 /net | |
parent | 05a4b58301c38fbb81cc10a79f246f3dea0043c5 (diff) |
svc: don't hold reference for poolstats, only mutex.
A future patch will remove refcounting on svc_serv as it is of little
use.
It is currently used to keep the svc around while the pool_stats file is
open.
Change this to get the pointer, protected by the mutex, only in
seq_start, and the release the mutex in seq_stop.
This means that if the nfsd server is stopped and restarted while the
pool_stats file it open, then some pool stats info could be from the
first instance and some from the second. This might appear odd, but is
unlikely to be a problem in practice.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'net')
-rw-r--r-- | net/sunrpc/svc_xprt.c | 32 |
1 files changed, 23 insertions, 9 deletions
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 1b71055fc391..b4a85a227bd7 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -1362,29 +1362,36 @@ int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen) } EXPORT_SYMBOL_GPL(svc_xprt_names); - /*----------------------------------------------------------------------------*/ static void *svc_pool_stats_start(struct seq_file *m, loff_t *pos) { unsigned int pidx = (unsigned int)*pos; - struct svc_serv *serv = m->private; + struct svc_info *si = m->private; dprintk("svc_pool_stats_start, *pidx=%u\n", pidx); + mutex_lock(si->mutex); + if (!pidx) return SEQ_START_TOKEN; - return (pidx > serv->sv_nrpools ? NULL : &serv->sv_pools[pidx-1]); + if (!si->serv) + return NULL; + return pidx > si->serv->sv_nrpools ? NULL + : &si->serv->sv_pools[pidx - 1]; } static void *svc_pool_stats_next(struct seq_file *m, void *p, loff_t *pos) { struct svc_pool *pool = p; - struct svc_serv *serv = m->private; + struct svc_info *si = m->private; + struct svc_serv *serv = si->serv; dprintk("svc_pool_stats_next, *pos=%llu\n", *pos); - if (p == SEQ_START_TOKEN) { + if (!serv) { + pool = NULL; + } else if (p == SEQ_START_TOKEN) { pool = &serv->sv_pools[0]; } else { unsigned int pidx = (pool - &serv->sv_pools[0]); @@ -1399,6 +1406,9 @@ static void *svc_pool_stats_next(struct seq_file *m, void *p, loff_t *pos) static void svc_pool_stats_stop(struct seq_file *m, void *p) { + struct svc_info *si = m->private; + + mutex_unlock(si->mutex); } static int svc_pool_stats_show(struct seq_file *m, void *p) @@ -1426,14 +1436,18 @@ static const struct seq_operations svc_pool_stats_seq_ops = { .show = svc_pool_stats_show, }; -int svc_pool_stats_open(struct svc_serv *serv, struct file *file) +int svc_pool_stats_open(struct svc_info *info, struct file *file) { + struct seq_file *seq; int err; err = seq_open(file, &svc_pool_stats_seq_ops); - if (!err) - ((struct seq_file *) file->private_data)->private = serv; - return err; + if (err) + return err; + seq = file->private_data; + seq->private = info; + + return 0; } EXPORT_SYMBOL(svc_pool_stats_open); |