mm: more likely reclaim MADV_SEQUENTIAL mappings
[linux-2.6.git] / kernel / rcutree_trace.c
1 /*
2  * Read-Copy Update tracing for classic implementation
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17  *
18  * Copyright IBM Corporation, 2008
19  *
20  * Papers:  http://www.rdrop.com/users/paulmck/RCU
21  *
22  * For detailed explanation of Read-Copy Update mechanism see -
23  *              Documentation/RCU
24  *
25  */
26 #include <linux/types.h>
27 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/spinlock.h>
30 #include <linux/smp.h>
31 #include <linux/rcupdate.h>
32 #include <linux/interrupt.h>
33 #include <linux/sched.h>
34 #include <asm/atomic.h>
35 #include <linux/bitops.h>
36 #include <linux/module.h>
37 #include <linux/completion.h>
38 #include <linux/moduleparam.h>
39 #include <linux/percpu.h>
40 #include <linux/notifier.h>
41 #include <linux/cpu.h>
42 #include <linux/mutex.h>
43 #include <linux/debugfs.h>
44 #include <linux/seq_file.h>
45
46 static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
47 {
48         if (!rdp->beenonline)
49                 return;
50         seq_printf(m, "%3d%cc=%ld g=%ld pq=%d pqc=%ld qp=%d rpfq=%ld rp=%x",
51                    rdp->cpu,
52                    cpu_is_offline(rdp->cpu) ? '!' : ' ',
53                    rdp->completed, rdp->gpnum,
54                    rdp->passed_quiesc, rdp->passed_quiesc_completed,
55                    rdp->qs_pending,
56                    rdp->n_rcu_pending_force_qs - rdp->n_rcu_pending,
57                    (int)(rdp->n_rcu_pending & 0xffff));
58 #ifdef CONFIG_NO_HZ
59         seq_printf(m, " dt=%d/%d dn=%d df=%lu",
60                    rdp->dynticks->dynticks,
61                    rdp->dynticks->dynticks_nesting,
62                    rdp->dynticks->dynticks_nmi,
63                    rdp->dynticks_fqs);
64 #endif /* #ifdef CONFIG_NO_HZ */
65         seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
66         seq_printf(m, " ql=%ld b=%ld\n", rdp->qlen, rdp->blimit);
67 }
68
69 #define PRINT_RCU_DATA(name, func, m) \
70         do { \
71                 int _p_r_d_i; \
72                 \
73                 for_each_possible_cpu(_p_r_d_i) \
74                         func(m, &per_cpu(name, _p_r_d_i)); \
75         } while (0)
76
77 static int show_rcudata(struct seq_file *m, void *unused)
78 {
79         seq_puts(m, "rcu:\n");
80         PRINT_RCU_DATA(rcu_data, print_one_rcu_data, m);
81         seq_puts(m, "rcu_bh:\n");
82         PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data, m);
83         return 0;
84 }
85
86 static int rcudata_open(struct inode *inode, struct file *file)
87 {
88         return single_open(file, show_rcudata, NULL);
89 }
90
91 static struct file_operations rcudata_fops = {
92         .owner = THIS_MODULE,
93         .open = rcudata_open,
94         .read = seq_read,
95         .llseek = seq_lseek,
96         .release = single_release,
97 };
98
99 static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
100 {
101         if (!rdp->beenonline)
102                 return;
103         seq_printf(m, "%d,%s,%ld,%ld,%d,%ld,%d,%ld,%ld",
104                    rdp->cpu,
105                    cpu_is_offline(rdp->cpu) ? "\"Y\"" : "\"N\"",
106                    rdp->completed, rdp->gpnum,
107                    rdp->passed_quiesc, rdp->passed_quiesc_completed,
108                    rdp->qs_pending,
109                    rdp->n_rcu_pending_force_qs - rdp->n_rcu_pending,
110                    rdp->n_rcu_pending);
111 #ifdef CONFIG_NO_HZ
112         seq_printf(m, ",%d,%d,%d,%lu",
113                    rdp->dynticks->dynticks,
114                    rdp->dynticks->dynticks_nesting,
115                    rdp->dynticks->dynticks_nmi,
116                    rdp->dynticks_fqs);
117 #endif /* #ifdef CONFIG_NO_HZ */
118         seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
119         seq_printf(m, ",%ld,%ld\n", rdp->qlen, rdp->blimit);
120 }
121
122 static int show_rcudata_csv(struct seq_file *m, void *unused)
123 {
124         seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",\"rpfq\",\"rp\",");
125 #ifdef CONFIG_NO_HZ
126         seq_puts(m, "\"dt\",\"dt nesting\",\"dn\",\"df\",");
127 #endif /* #ifdef CONFIG_NO_HZ */
128         seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\"\n");
129         seq_puts(m, "\"rcu:\"\n");
130         PRINT_RCU_DATA(rcu_data, print_one_rcu_data_csv, m);
131         seq_puts(m, "\"rcu_bh:\"\n");
132         PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m);
133         return 0;
134 }
135
136 static int rcudata_csv_open(struct inode *inode, struct file *file)
137 {
138         return single_open(file, show_rcudata_csv, NULL);
139 }
140
141 static struct file_operations rcudata_csv_fops = {
142         .owner = THIS_MODULE,
143         .open = rcudata_csv_open,
144         .read = seq_read,
145         .llseek = seq_lseek,
146         .release = single_release,
147 };
148
149 static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
150 {
151         int level = 0;
152         struct rcu_node *rnp;
153
154         seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x "
155                       "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n",
156                    rsp->completed, rsp->gpnum, rsp->signaled,
157                    (long)(rsp->jiffies_force_qs - jiffies),
158                    (int)(jiffies & 0xffff),
159                    rsp->n_force_qs, rsp->n_force_qs_ngp,
160                    rsp->n_force_qs - rsp->n_force_qs_ngp,
161                    rsp->n_force_qs_lh);
162         for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) {
163                 if (rnp->level != level) {
164                         seq_puts(m, "\n");
165                         level = rnp->level;
166                 }
167                 seq_printf(m, "%lx/%lx %d:%d ^%d    ",
168                            rnp->qsmask, rnp->qsmaskinit,
169                            rnp->grplo, rnp->grphi, rnp->grpnum);
170         }
171         seq_puts(m, "\n");
172 }
173
174 static int show_rcuhier(struct seq_file *m, void *unused)
175 {
176         seq_puts(m, "rcu:\n");
177         print_one_rcu_state(m, &rcu_state);
178         seq_puts(m, "rcu_bh:\n");
179         print_one_rcu_state(m, &rcu_bh_state);
180         return 0;
181 }
182
183 static int rcuhier_open(struct inode *inode, struct file *file)
184 {
185         return single_open(file, show_rcuhier, NULL);
186 }
187
188 static struct file_operations rcuhier_fops = {
189         .owner = THIS_MODULE,
190         .open = rcuhier_open,
191         .read = seq_read,
192         .llseek = seq_lseek,
193         .release = single_release,
194 };
195
196 static int show_rcugp(struct seq_file *m, void *unused)
197 {
198         seq_printf(m, "rcu: completed=%ld  gpnum=%ld\n",
199                    rcu_state.completed, rcu_state.gpnum);
200         seq_printf(m, "rcu_bh: completed=%ld  gpnum=%ld\n",
201                    rcu_bh_state.completed, rcu_bh_state.gpnum);
202         return 0;
203 }
204
205 static int rcugp_open(struct inode *inode, struct file *file)
206 {
207         return single_open(file, show_rcugp, NULL);
208 }
209
210 static struct file_operations rcugp_fops = {
211         .owner = THIS_MODULE,
212         .open = rcugp_open,
213         .read = seq_read,
214         .llseek = seq_lseek,
215         .release = single_release,
216 };
217
218 static struct dentry *rcudir, *datadir, *datadir_csv, *hierdir, *gpdir;
219 static int __init rcuclassic_trace_init(void)
220 {
221         rcudir = debugfs_create_dir("rcu", NULL);
222         if (!rcudir)
223                 goto out;
224
225         datadir = debugfs_create_file("rcudata", 0444, rcudir,
226                                                 NULL, &rcudata_fops);
227         if (!datadir)
228                 goto free_out;
229
230         datadir_csv = debugfs_create_file("rcudata.csv", 0444, rcudir,
231                                                 NULL, &rcudata_csv_fops);
232         if (!datadir_csv)
233                 goto free_out;
234
235         gpdir = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
236         if (!gpdir)
237                 goto free_out;
238
239         hierdir = debugfs_create_file("rcuhier", 0444, rcudir,
240                                                 NULL, &rcuhier_fops);
241         if (!hierdir)
242                 goto free_out;
243         return 0;
244 free_out:
245         if (datadir)
246                 debugfs_remove(datadir);
247         if (datadir_csv)
248                 debugfs_remove(datadir_csv);
249         if (gpdir)
250                 debugfs_remove(gpdir);
251         debugfs_remove(rcudir);
252 out:
253         return 1;
254 }
255
256 static void __exit rcuclassic_trace_cleanup(void)
257 {
258         debugfs_remove(datadir);
259         debugfs_remove(datadir_csv);
260         debugfs_remove(gpdir);
261         debugfs_remove(hierdir);
262         debugfs_remove(rcudir);
263 }
264
265
266 module_init(rcuclassic_trace_init);
267 module_exit(rcuclassic_trace_cleanup);
268
269 MODULE_AUTHOR("Paul E. McKenney");
270 MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
271 MODULE_LICENSE("GPL");