From 016583d7030cec9b69e0d55269a5967f4ee871d2 Mon Sep 17 00:00:00 2001 From: Dave Wysochanski Date: Tue, 31 Jul 2018 10:10:51 -0400 Subject: sunrpc: Change rpc_print_iostats to rpc_clnt_show_stats and handle rpc_clnt clones The existing rpc_print_iostats has a few shortcomings. First, the naming is not consistent with other functions in the kernel that display stats. Second, it is really displaying stats for an rpc_clnt structure as it displays both xprt stats and per-op stats. Third, it does not handle rpc_clnt clones, which is important for the one in-kernel tree caller of this function, the NFS client's nfs_show_stats function. Fix all of the above by renaming the rpc_print_iostats to rpc_clnt_show_stats and looping through any rpc_clnt clones via cl_parent. Once this interface is fixed, this addresses a problem with NFSv4. Before this patch, the /proc/self/mountstats always showed incorrect counts for NFSv4 lease and session related opcodes such as SEQUENCE, RENEW, SETCLIENTID, CREATE_SESSION, etc. These counts were always 0 even though many ops would go over the wire. The reason for this is there are multiple rpc_clnt structures allocated for any given NFSv4 mount, and inside nfs_show_stats() we callled into rpc_print_iostats() which only handled one of them, nfs_server->client. Fix these counts by calling sunrpc's new rpc_clnt_show_stats() function, which handles cloned rpc_clnt structs and prints the stats together. Note that one side-effect of the above is that multiple mounts from the same NFS server will show identical counts in the above ops due to the fact the one rpc_clnt (representing the NFSv4 client state) is shared across mounts. Signed-off-by: Dave Wysochanski Signed-off-by: Anna Schumaker --- fs/nfs/super.c | 2 +- include/linux/sunrpc/metrics.h | 4 ++-- net/sunrpc/stats.c | 17 ++++++++++++----- 3 files changed, 15 insertions(+), 8 deletions(-) diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 5e470e233c83..bdf39fa1bfbc 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -884,7 +884,7 @@ int nfs_show_stats(struct seq_file *m, struct dentry *root) #endif seq_printf(m, "\n"); - rpc_print_iostats(m, nfss->client); + rpc_clnt_show_stats(m, nfss->client); return 0; } diff --git a/include/linux/sunrpc/metrics.h b/include/linux/sunrpc/metrics.h index 9baed7b355b2..1b3751327575 100644 --- a/include/linux/sunrpc/metrics.h +++ b/include/linux/sunrpc/metrics.h @@ -82,7 +82,7 @@ void rpc_count_iostats(const struct rpc_task *, struct rpc_iostats *); void rpc_count_iostats_metrics(const struct rpc_task *, struct rpc_iostats *); -void rpc_print_iostats(struct seq_file *, struct rpc_clnt *); +void rpc_clnt_show_stats(struct seq_file *, struct rpc_clnt *); void rpc_free_iostats(struct rpc_iostats *); #else /* CONFIG_PROC_FS */ @@ -95,7 +95,7 @@ static inline void rpc_count_iostats_metrics(const struct rpc_task *task, { } -static inline void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt) {} +static inline void rpc_clnt_show_stats(struct seq_file *seq, struct rpc_clnt *clnt) {} static inline void rpc_free_iostats(struct rpc_iostats *stats) {} #endif /* CONFIG_PROC_FS */ diff --git a/net/sunrpc/stats.c b/net/sunrpc/stats.c index 32adddd7fb78..ffae7c2245b1 100644 --- a/net/sunrpc/stats.c +++ b/net/sunrpc/stats.c @@ -235,13 +235,12 @@ static void _print_rpc_iostats(struct seq_file *seq, struct rpc_iostats *stats, ktime_to_ms(stats->om_execute)); } -void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt) +void rpc_clnt_show_stats(struct seq_file *seq, struct rpc_clnt *clnt) { - struct rpc_iostats *stats = clnt->cl_metrics; struct rpc_xprt *xprt; unsigned int op, maxproc = clnt->cl_maxproc; - if (!stats) + if (!clnt->cl_metrics) return; seq_printf(seq, "\tRPC iostats version: %s ", RPC_IOSTATS_VERS); @@ -256,10 +255,18 @@ void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt) seq_printf(seq, "\tper-op statistics\n"); for (op = 0; op < maxproc; op++) { - _print_rpc_iostats(seq, &stats[op], op, clnt->cl_procinfo); + struct rpc_iostats stats = {}; + struct rpc_clnt *next = clnt; + do { + _add_rpc_iostats(&stats, &next->cl_metrics[op]); + if (next == next->cl_parent) + break; + next = next->cl_parent; + } while (next); + _print_rpc_iostats(seq, &stats, op, clnt->cl_procinfo); } } -EXPORT_SYMBOL_GPL(rpc_print_iostats); +EXPORT_SYMBOL_GPL(rpc_clnt_show_stats); /* * Register/unregister RPC proc files -- cgit v1.2.1