/*
   * Read-Copy Update tracing for classic implementation
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
   *
   * Copyright IBM Corporation, 2008
   *
   * Papers:  http://www.rdrop.com/users/paulmck/RCU
   *
   * For detailed explanation of Read-Copy Update mechanism see -

   *		Documentation/RCU

   *
   */
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/init.h>
  #include <linux/spinlock.h>
  #include <linux/smp.h>
  #include <linux/rcupdate.h>
  #include <linux/interrupt.h>
  #include <linux/sched.h>
  #include <asm/atomic.h>
  #include <linux/bitops.h>
  #include <linux/module.h>
  #include <linux/completion.h>
  #include <linux/moduleparam.h>
  #include <linux/percpu.h>
  #include <linux/notifier.h>
  #include <linux/cpu.h>
  #include <linux/mutex.h>
  #include <linux/debugfs.h>
  #include <linux/seq_file.h>

  #define RCU_TREE_NONCORE

  #include "rcutree.h"

  static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
  {
  	if (!rdp->beenonline)
  		return;

  	seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pqc=%lu qp=%d",

  		   rdp->cpu,
  		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
  		   rdp->completed, rdp->gpnum,
  		   rdp->passed_quiesc, rdp->passed_quiesc_completed,

  		   rdp->qs_pending);

  #ifdef CONFIG_NO_HZ
  	seq_printf(m, " dt=%d/%d dn=%d df=%lu",
  		   rdp->dynticks->dynticks,
  		   rdp->dynticks->dynticks_nesting,
  		   rdp->dynticks->dynticks_nmi,
  		   rdp->dynticks_fqs);
  #endif /* #ifdef CONFIG_NO_HZ */
  	seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
  	seq_printf(m, " ql=%ld b=%ld
  ", rdp->qlen, rdp->blimit);
  }
  
  #define PRINT_RCU_DATA(name, func, m) \
  	do { \
  		int _p_r_d_i; \
  		\
  		for_each_possible_cpu(_p_r_d_i) \
  			func(m, &per_cpu(name, _p_r_d_i)); \
  	} while (0)
  
  static int show_rcudata(struct seq_file *m, void *unused)
  {

  #ifdef CONFIG_TREE_PREEMPT_RCU
  	seq_puts(m, "rcu_preempt:
  ");
  	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data, m);
  #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */

  	seq_puts(m, "rcu_sched:
  ");
  	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data, m);

  	seq_puts(m, "rcu_bh:
  ");
  	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data, m);
  	return 0;
  }
  
  static int rcudata_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, show_rcudata, NULL);
  }

  static const struct file_operations rcudata_fops = {

  	.owner = THIS_MODULE,
  	.open = rcudata_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
  {
  	if (!rdp->beenonline)
  		return;

  	seq_printf(m, "%d,%s,%lu,%lu,%d,%lu,%d",

  		   rdp->cpu,

  		   cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"",

  		   rdp->completed, rdp->gpnum,
  		   rdp->passed_quiesc, rdp->passed_quiesc_completed,

  		   rdp->qs_pending);

  #ifdef CONFIG_NO_HZ
  	seq_printf(m, ",%d,%d,%d,%lu",
  		   rdp->dynticks->dynticks,
  		   rdp->dynticks->dynticks_nesting,
  		   rdp->dynticks->dynticks_nmi,
  		   rdp->dynticks_fqs);
  #endif /* #ifdef CONFIG_NO_HZ */
  	seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
  	seq_printf(m, ",%ld,%ld
  ", rdp->qlen, rdp->blimit);
  }
  
  static int show_rcudata_csv(struct seq_file *m, void *unused)
  {

  	seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",");

  #ifdef CONFIG_NO_HZ
  	seq_puts(m, "\"dt\",\"dt nesting\",\"dn\",\"df\",");
  #endif /* #ifdef CONFIG_NO_HZ */
  	seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\"
  ");

  #ifdef CONFIG_TREE_PREEMPT_RCU
  	seq_puts(m, "\"rcu_preempt:\"
  ");
  	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m);
  #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */

  	seq_puts(m, "\"rcu_sched:\"
  ");
  	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data_csv, m);

  	seq_puts(m, "\"rcu_bh:\"
  ");
  	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m);
  	return 0;
  }
  
  static int rcudata_csv_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, show_rcudata_csv, NULL);
  }

  static const struct file_operations rcudata_csv_fops = {

  	.owner = THIS_MODULE,
  	.open = rcudata_csv_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
  {

  	unsigned long gpnum;

  	int level = 0;

  	int phase;

  	struct rcu_node *rnp;

  	gpnum = rsp->gpnum;

  	seq_printf(m, "c=%lu g=%lu s=%d jfq=%ld j=%x "

  		      "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld
  ",

  		   rsp->completed, gpnum, rsp->signaled,

  		   (long)(rsp->jiffies_force_qs - jiffies),
  		   (int)(jiffies & 0xffff),
  		   rsp->n_force_qs, rsp->n_force_qs_ngp,
  		   rsp->n_force_qs - rsp->n_force_qs_ngp,

  		   rsp->n_force_qs_lh, rsp->orphan_qlen);

  	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) {
  		if (rnp->level != level) {
  			seq_puts(m, "
  ");
  			level = rnp->level;
  		}

  		phase = gpnum & 0x1;
  		seq_printf(m, "%lx/%lx %c%c>%c%c %d:%d ^%d    ",

  			   rnp->qsmask, rnp->qsmaskinit,

  			   "T."[list_empty(&rnp->blocked_tasks[phase])],
  			   "E."[list_empty(&rnp->blocked_tasks[phase + 2])],
  			   "T."[list_empty(&rnp->blocked_tasks[!phase])],
  			   "E."[list_empty(&rnp->blocked_tasks[!phase + 2])],

  			   rnp->grplo, rnp->grphi, rnp->grpnum);
  	}
  	seq_puts(m, "
  ");
  }
  
  static int show_rcuhier(struct seq_file *m, void *unused)
  {

  #ifdef CONFIG_TREE_PREEMPT_RCU
  	seq_puts(m, "rcu_preempt:
  ");
  	print_one_rcu_state(m, &rcu_preempt_state);
  #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */

  	seq_puts(m, "rcu_sched:
  ");
  	print_one_rcu_state(m, &rcu_sched_state);

  	seq_puts(m, "rcu_bh:
  ");
  	print_one_rcu_state(m, &rcu_bh_state);
  	return 0;
  }
  
  static int rcuhier_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, show_rcuhier, NULL);
  }

  static const struct file_operations rcuhier_fops = {

  	.owner = THIS_MODULE,
  	.open = rcuhier_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  static int show_rcugp(struct seq_file *m, void *unused)
  {

  #ifdef CONFIG_TREE_PREEMPT_RCU

  	seq_printf(m, "rcu_preempt: completed=%ld  gpnum=%lu
  ",

  		   rcu_preempt_state.completed, rcu_preempt_state.gpnum);
  #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */

  	seq_printf(m, "rcu_sched: completed=%ld  gpnum=%lu
  ",

  		   rcu_sched_state.completed, rcu_sched_state.gpnum);

  	seq_printf(m, "rcu_bh: completed=%ld  gpnum=%lu
  ",

  		   rcu_bh_state.completed, rcu_bh_state.gpnum);
  	return 0;
  }
  
  static int rcugp_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, show_rcugp, NULL);
  }

  static const struct file_operations rcugp_fops = {

  	.owner = THIS_MODULE,
  	.open = rcugp_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };

  static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp)
  {
  	seq_printf(m, "%3d%cnp=%ld "

  		   "qsp=%ld rpq=%ld cbr=%ld cng=%ld "
  		   "gpc=%ld gps=%ld nf=%ld nn=%ld
  ",

  		   rdp->cpu,
  		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
  		   rdp->n_rcu_pending,
  		   rdp->n_rp_qs_pending,

  		   rdp->n_rp_report_qs,

  		   rdp->n_rp_cb_ready,
  		   rdp->n_rp_cpu_needs_gp,
  		   rdp->n_rp_gp_completed,
  		   rdp->n_rp_gp_started,
  		   rdp->n_rp_need_fqs,
  		   rdp->n_rp_need_nothing);
  }
  
  static void print_rcu_pendings(struct seq_file *m, struct rcu_state *rsp)
  {
  	int cpu;
  	struct rcu_data *rdp;
  
  	for_each_possible_cpu(cpu) {
  		rdp = rsp->rda[cpu];
  		if (rdp->beenonline)
  			print_one_rcu_pending(m, rdp);
  	}
  }
  
  static int show_rcu_pending(struct seq_file *m, void *unused)
  {

  #ifdef CONFIG_TREE_PREEMPT_RCU
  	seq_puts(m, "rcu_preempt:
  ");
  	print_rcu_pendings(m, &rcu_preempt_state);
  #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */

  	seq_puts(m, "rcu_sched:
  ");
  	print_rcu_pendings(m, &rcu_sched_state);

  	seq_puts(m, "rcu_bh:
  ");
  	print_rcu_pendings(m, &rcu_bh_state);
  	return 0;
  }
  
  static int rcu_pending_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, show_rcu_pending, NULL);
  }

  static const struct file_operations rcu_pending_fops = {

  	.owner = THIS_MODULE,
  	.open = rcu_pending_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  static struct dentry *rcudir;

  static int __init rcuclassic_trace_init(void)
  {

  	struct dentry *retval;

  	rcudir = debugfs_create_dir("rcu", NULL);
  	if (!rcudir)

  		goto free_out;

  	retval = debugfs_create_file("rcudata", 0444, rcudir,

  						NULL, &rcudata_fops);

  	if (!retval)

  		goto free_out;

  	retval = debugfs_create_file("rcudata.csv", 0444, rcudir,

  						NULL, &rcudata_csv_fops);

  	if (!retval)

  		goto free_out;

  	retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
  	if (!retval)

  		goto free_out;

  	retval = debugfs_create_file("rcuhier", 0444, rcudir,

  						NULL, &rcuhier_fops);

  	if (!retval)

  		goto free_out;

  	retval = debugfs_create_file("rcu_pending", 0444, rcudir,

  						NULL, &rcu_pending_fops);

  	if (!retval)

  		goto free_out;

  	return 0;
  free_out:

  	debugfs_remove_recursive(rcudir);

  	return 1;
  }
  
  static void __exit rcuclassic_trace_cleanup(void)
  {

  	debugfs_remove_recursive(rcudir);

  }
  
  
  module_init(rcuclassic_trace_init);
  module_exit(rcuclassic_trace_cleanup);
  
  MODULE_AUTHOR("Paul E. McKenney");
  MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
  MODULE_LICENSE("GPL");