linux/net/sunrpc/stats.c
Chuck Lever edef1297f3 SUNRPC: serialize iostats updates
Occasionally mountstats reports a negative retransmission rate.
Ensure that two RPCs completing concurrently don't confuse the sums
in the transport's op_metrics array.

Since pNFS filelayout can invoke rpc_count_iostats() on another
transport from xprt_release(), we can't rely on simply holding the
transport_lock in xprt_release(). There's nothing for it but hard
serialization. One spin lock per RPC operation should make this as
painless as it can be.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2014-11-25 16:22:15 -05:00

293 lines
7.1 KiB
C

/*
* linux/net/sunrpc/stats.c
*
* procfs-based user access to generic RPC statistics. The stats files
* reside in /proc/net/rpc.
*
* The read routines assume that the buffer passed in is just big enough.
* If you implement an RPC service that has its own stats routine which
* appends the generic RPC stats, make sure you don't exceed the PAGE_SIZE
* limit.
*
* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/metrics.h>
#include <linux/rcupdate.h>
#include "netns.h"
#define RPCDBG_FACILITY RPCDBG_MISC
/*
* Get RPC client stats
*/
static int rpc_proc_show(struct seq_file *seq, void *v) {
const struct rpc_stat *statp = seq->private;
const struct rpc_program *prog = statp->program;
unsigned int i, j;
seq_printf(seq,
"net %u %u %u %u\n",
statp->netcnt,
statp->netudpcnt,
statp->nettcpcnt,
statp->nettcpconn);
seq_printf(seq,
"rpc %u %u %u\n",
statp->rpccnt,
statp->rpcretrans,
statp->rpcauthrefresh);
for (i = 0; i < prog->nrvers; i++) {
const struct rpc_version *vers = prog->version[i];
if (!vers)
continue;
seq_printf(seq, "proc%u %u",
vers->number, vers->nrprocs);
for (j = 0; j < vers->nrprocs; j++)
seq_printf(seq, " %u",
vers->procs[j].p_count);
seq_putc(seq, '\n');
}
return 0;
}
static int rpc_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, rpc_proc_show, PDE_DATA(inode));
}
static const struct file_operations rpc_proc_fops = {
.owner = THIS_MODULE,
.open = rpc_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
/*
* Get RPC server stats
*/
void svc_seq_show(struct seq_file *seq, const struct svc_stat *statp) {
const struct svc_program *prog = statp->program;
const struct svc_procedure *proc;
const struct svc_version *vers;
unsigned int i, j;
seq_printf(seq,
"net %u %u %u %u\n",
statp->netcnt,
statp->netudpcnt,
statp->nettcpcnt,
statp->nettcpconn);
seq_printf(seq,
"rpc %u %u %u %u %u\n",
statp->rpccnt,
statp->rpcbadfmt+statp->rpcbadauth+statp->rpcbadclnt,
statp->rpcbadfmt,
statp->rpcbadauth,
statp->rpcbadclnt);
for (i = 0; i < prog->pg_nvers; i++) {
if (!(vers = prog->pg_vers[i]) || !(proc = vers->vs_proc))
continue;
seq_printf(seq, "proc%d %u", i, vers->vs_nproc);
for (j = 0; j < vers->vs_nproc; j++, proc++)
seq_printf(seq, " %u", proc->pc_count);
seq_putc(seq, '\n');
}
}
EXPORT_SYMBOL_GPL(svc_seq_show);
/**
* rpc_alloc_iostats - allocate an rpc_iostats structure
* @clnt: RPC program, version, and xprt
*
*/
struct rpc_iostats *rpc_alloc_iostats(struct rpc_clnt *clnt)
{
struct rpc_iostats *stats;
int i;
stats = kcalloc(clnt->cl_maxproc, sizeof(*stats), GFP_KERNEL);
if (stats) {
for (i = 0; i < clnt->cl_maxproc; i++)
spin_lock_init(&stats[i].om_lock);
}
return stats;
}
EXPORT_SYMBOL_GPL(rpc_alloc_iostats);
/**
* rpc_free_iostats - release an rpc_iostats structure
* @stats: doomed rpc_iostats structure
*
*/
void rpc_free_iostats(struct rpc_iostats *stats)
{
kfree(stats);
}
EXPORT_SYMBOL_GPL(rpc_free_iostats);
/**
* rpc_count_iostats - tally up per-task stats
* @task: completed rpc_task
* @stats: array of stat structures
*/
void rpc_count_iostats(const struct rpc_task *task, struct rpc_iostats *stats)
{
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_iostats *op_metrics;
ktime_t delta, now;
if (!stats || !req)
return;
now = ktime_get();
op_metrics = &stats[task->tk_msg.rpc_proc->p_statidx];
spin_lock(&op_metrics->om_lock);
op_metrics->om_ops++;
op_metrics->om_ntrans += req->rq_ntrans;
op_metrics->om_timeouts += task->tk_timeouts;
op_metrics->om_bytes_sent += req->rq_xmit_bytes_sent;
op_metrics->om_bytes_recv += req->rq_reply_bytes_recvd;
delta = ktime_sub(req->rq_xtime, task->tk_start);
op_metrics->om_queue = ktime_add(op_metrics->om_queue, delta);
op_metrics->om_rtt = ktime_add(op_metrics->om_rtt, req->rq_rtt);
delta = ktime_sub(now, task->tk_start);
op_metrics->om_execute = ktime_add(op_metrics->om_execute, delta);
spin_unlock(&op_metrics->om_lock);
}
EXPORT_SYMBOL_GPL(rpc_count_iostats);
static void _print_name(struct seq_file *seq, unsigned int op,
struct rpc_procinfo *procs)
{
if (procs[op].p_name)
seq_printf(seq, "\t%12s: ", procs[op].p_name);
else if (op == 0)
seq_printf(seq, "\t NULL: ");
else
seq_printf(seq, "\t%12u: ", op);
}
void rpc_print_iostats(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)
return;
seq_printf(seq, "\tRPC iostats version: %s ", RPC_IOSTATS_VERS);
seq_printf(seq, "p/v: %u/%u (%s)\n",
clnt->cl_prog, clnt->cl_vers, clnt->cl_program->name);
rcu_read_lock();
xprt = rcu_dereference(clnt->cl_xprt);
if (xprt)
xprt->ops->print_stats(xprt, seq);
rcu_read_unlock();
seq_printf(seq, "\tper-op statistics\n");
for (op = 0; op < maxproc; op++) {
struct rpc_iostats *metrics = &stats[op];
_print_name(seq, op, clnt->cl_procinfo);
seq_printf(seq, "%lu %lu %lu %Lu %Lu %Lu %Lu %Lu\n",
metrics->om_ops,
metrics->om_ntrans,
metrics->om_timeouts,
metrics->om_bytes_sent,
metrics->om_bytes_recv,
ktime_to_ms(metrics->om_queue),
ktime_to_ms(metrics->om_rtt),
ktime_to_ms(metrics->om_execute));
}
}
EXPORT_SYMBOL_GPL(rpc_print_iostats);
/*
* Register/unregister RPC proc files
*/
static inline struct proc_dir_entry *
do_register(struct net *net, const char *name, void *data,
const struct file_operations *fops)
{
struct sunrpc_net *sn;
dprintk("RPC: registering /proc/net/rpc/%s\n", name);
sn = net_generic(net, sunrpc_net_id);
return proc_create_data(name, 0, sn->proc_net_rpc, fops, data);
}
struct proc_dir_entry *
rpc_proc_register(struct net *net, struct rpc_stat *statp)
{
return do_register(net, statp->program->name, statp, &rpc_proc_fops);
}
EXPORT_SYMBOL_GPL(rpc_proc_register);
void
rpc_proc_unregister(struct net *net, const char *name)
{
struct sunrpc_net *sn;
sn = net_generic(net, sunrpc_net_id);
remove_proc_entry(name, sn->proc_net_rpc);
}
EXPORT_SYMBOL_GPL(rpc_proc_unregister);
struct proc_dir_entry *
svc_proc_register(struct net *net, struct svc_stat *statp, const struct file_operations *fops)
{
return do_register(net, statp->program->pg_name, statp, fops);
}
EXPORT_SYMBOL_GPL(svc_proc_register);
void
svc_proc_unregister(struct net *net, const char *name)
{
struct sunrpc_net *sn;
sn = net_generic(net, sunrpc_net_id);
remove_proc_entry(name, sn->proc_net_rpc);
}
EXPORT_SYMBOL_GPL(svc_proc_unregister);
int rpc_proc_init(struct net *net)
{
struct sunrpc_net *sn;
dprintk("RPC: registering /proc/net/rpc\n");
sn = net_generic(net, sunrpc_net_id);
sn->proc_net_rpc = proc_mkdir("rpc", net->proc_net);
if (sn->proc_net_rpc == NULL)
return -ENOMEM;
return 0;
}
void rpc_proc_exit(struct net *net)
{
dprintk("RPC: unregistering /proc/net/rpc\n");
remove_proc_entry("rpc", net->proc_net);
}