/*
   * 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
  ",
  			statp->netcnt,
  			statp->netudpcnt,
  			statp->nettcpcnt,
  			statp->nettcpconn);
  	seq_printf(seq,
  		"rpc %u %u %u
  ",
  			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, '
  ');
  	}
  	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
  ",
  			statp->netcnt,
  			statp->netudpcnt,
  			statp->nettcpcnt,
  			statp->nettcpconn);
  	seq_printf(seq,
  		"rpc %u %u %u %u %u
  ",
  			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, '
  ');
  	}
  }
  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)
  {
  	return kcalloc(clnt->cl_maxproc, sizeof(struct rpc_iostats), GFP_KERNEL);
  }
  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
   *
   * Relies on the caller for serialization.
   */
  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;
  
  	if (!stats || !req)
  		return;
  
  	op_metrics = &stats[task->tk_msg.rpc_proc->p_statidx];
  
  	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(ktime_get(), task->tk_start);
  	op_metrics->om_execute = ktime_add(op_metrics->om_execute, delta);
  }
  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)
  ",
  			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
  ");
  	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
  ",
  				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
  ", 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
  ");
  	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
  ");
  	remove_proc_entry("rpc", net->proc_net);
  }