tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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#include "rcutree.h"
47
48static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
49{
50 if (!rdp->beenonline)
51 return;
52 seq_printf(m, "%3d%cc=%ld g=%ld pq=%d pqc=%ld qp=%d",
53 rdp->cpu,
54 cpu_is_offline(rdp->cpu) ? '!' : ' ',
55 rdp->completed, rdp->gpnum,
56 rdp->passed_quiesc, rdp->passed_quiesc_completed,
57 rdp->qs_pending);
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
77static 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
86static int rcudata_open(struct inode *inode, struct file *file)
87{
88 return single_open(file, show_rcudata, NULL);
89}
90
91static 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
99static 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",
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#ifdef CONFIG_NO_HZ
110 seq_printf(m, ",%d,%d,%d,%lu",
111 rdp->dynticks->dynticks,
112 rdp->dynticks->dynticks_nesting,
113 rdp->dynticks->dynticks_nmi,
114 rdp->dynticks_fqs);
115#endif /* #ifdef CONFIG_NO_HZ */
116 seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
117 seq_printf(m, ",%ld,%ld\n", rdp->qlen, rdp->blimit);
118}
119
120static int show_rcudata_csv(struct seq_file *m, void *unused)
121{
122 seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",");
123#ifdef CONFIG_NO_HZ
124 seq_puts(m, "\"dt\",\"dt nesting\",\"dn\",\"df\",");
125#endif /* #ifdef CONFIG_NO_HZ */
126 seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\"\n");
127 seq_puts(m, "\"rcu:\"\n");
128 PRINT_RCU_DATA(rcu_data, print_one_rcu_data_csv, m);
129 seq_puts(m, "\"rcu_bh:\"\n");
130 PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m);
131 return 0;
132}
133
134static int rcudata_csv_open(struct inode *inode, struct file *file)
135{
136 return single_open(file, show_rcudata_csv, NULL);
137}
138
139static struct file_operations rcudata_csv_fops = {
140 .owner = THIS_MODULE,
141 .open = rcudata_csv_open,
142 .read = seq_read,
143 .llseek = seq_lseek,
144 .release = single_release,
145};
146
147static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
148{
149 int level = 0;
150 struct rcu_node *rnp;
151
152 seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x "
153 "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n",
154 rsp->completed, rsp->gpnum, rsp->signaled,
155 (long)(rsp->jiffies_force_qs - jiffies),
156 (int)(jiffies & 0xffff),
157 rsp->n_force_qs, rsp->n_force_qs_ngp,
158 rsp->n_force_qs - rsp->n_force_qs_ngp,
159 rsp->n_force_qs_lh);
160 for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) {
161 if (rnp->level != level) {
162 seq_puts(m, "\n");
163 level = rnp->level;
164 }
165 seq_printf(m, "%lx/%lx %d:%d ^%d ",
166 rnp->qsmask, rnp->qsmaskinit,
167 rnp->grplo, rnp->grphi, rnp->grpnum);
168 }
169 seq_puts(m, "\n");
170}
171
172static int show_rcuhier(struct seq_file *m, void *unused)
173{
174 seq_puts(m, "rcu:\n");
175 print_one_rcu_state(m, &rcu_state);
176 seq_puts(m, "rcu_bh:\n");
177 print_one_rcu_state(m, &rcu_bh_state);
178 return 0;
179}
180
181static int rcuhier_open(struct inode *inode, struct file *file)
182{
183 return single_open(file, show_rcuhier, NULL);
184}
185
186static struct file_operations rcuhier_fops = {
187 .owner = THIS_MODULE,
188 .open = rcuhier_open,
189 .read = seq_read,
190 .llseek = seq_lseek,
191 .release = single_release,
192};
193
194static int show_rcugp(struct seq_file *m, void *unused)
195{
196 seq_printf(m, "rcu: completed=%ld gpnum=%ld\n",
197 rcu_state.completed, rcu_state.gpnum);
198 seq_printf(m, "rcu_bh: completed=%ld gpnum=%ld\n",
199 rcu_bh_state.completed, rcu_bh_state.gpnum);
200 return 0;
201}
202
203static int rcugp_open(struct inode *inode, struct file *file)
204{
205 return single_open(file, show_rcugp, NULL);
206}
207
208static struct file_operations rcugp_fops = {
209 .owner = THIS_MODULE,
210 .open = rcugp_open,
211 .read = seq_read,
212 .llseek = seq_lseek,
213 .release = single_release,
214};
215
216static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp)
217{
218 seq_printf(m, "%3d%cnp=%ld "
219 "qsp=%ld cbr=%ld cng=%ld gpc=%ld gps=%ld nf=%ld nn=%ld\n",
220 rdp->cpu,
221 cpu_is_offline(rdp->cpu) ? '!' : ' ',
222 rdp->n_rcu_pending,
223 rdp->n_rp_qs_pending,
224 rdp->n_rp_cb_ready,
225 rdp->n_rp_cpu_needs_gp,
226 rdp->n_rp_gp_completed,
227 rdp->n_rp_gp_started,
228 rdp->n_rp_need_fqs,
229 rdp->n_rp_need_nothing);
230}
231
232static void print_rcu_pendings(struct seq_file *m, struct rcu_state *rsp)
233{
234 int cpu;
235 struct rcu_data *rdp;
236
237 for_each_possible_cpu(cpu) {
238 rdp = rsp->rda[cpu];
239 if (rdp->beenonline)
240 print_one_rcu_pending(m, rdp);
241 }
242}
243
244static int show_rcu_pending(struct seq_file *m, void *unused)
245{
246 seq_puts(m, "rcu:\n");
247 print_rcu_pendings(m, &rcu_state);
248 seq_puts(m, "rcu_bh:\n");
249 print_rcu_pendings(m, &rcu_bh_state);
250 return 0;
251}
252
253static int rcu_pending_open(struct inode *inode, struct file *file)
254{
255 return single_open(file, show_rcu_pending, NULL);
256}
257
258static struct file_operations rcu_pending_fops = {
259 .owner = THIS_MODULE,
260 .open = rcu_pending_open,
261 .read = seq_read,
262 .llseek = seq_lseek,
263 .release = single_release,
264};
265
266static struct dentry *rcudir;
267static struct dentry *datadir;
268static struct dentry *datadir_csv;
269static struct dentry *gpdir;
270static struct dentry *hierdir;
271static struct dentry *rcu_pendingdir;
272
273static int __init rcuclassic_trace_init(void)
274{
275 rcudir = debugfs_create_dir("rcu", NULL);
276 if (!rcudir)
277 goto out;
278
279 datadir = debugfs_create_file("rcudata", 0444, rcudir,
280 NULL, &rcudata_fops);
281 if (!datadir)
282 goto free_out;
283
284 datadir_csv = debugfs_create_file("rcudata.csv", 0444, rcudir,
285 NULL, &rcudata_csv_fops);
286 if (!datadir_csv)
287 goto free_out;
288
289 gpdir = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
290 if (!gpdir)
291 goto free_out;
292
293 hierdir = debugfs_create_file("rcuhier", 0444, rcudir,
294 NULL, &rcuhier_fops);
295 if (!hierdir)
296 goto free_out;
297
298 rcu_pendingdir = debugfs_create_file("rcu_pending", 0444, rcudir,
299 NULL, &rcu_pending_fops);
300 if (!rcu_pendingdir)
301 goto free_out;
302 return 0;
303free_out:
304 if (datadir)
305 debugfs_remove(datadir);
306 if (datadir_csv)
307 debugfs_remove(datadir_csv);
308 if (gpdir)
309 debugfs_remove(gpdir);
310 debugfs_remove(rcudir);
311out:
312 return 1;
313}
314
315static void __exit rcuclassic_trace_cleanup(void)
316{
317 debugfs_remove(datadir);
318 debugfs_remove(datadir_csv);
319 debugfs_remove(gpdir);
320 debugfs_remove(hierdir);
321 debugfs_remove(rcu_pendingdir);
322 debugfs_remove(rcudir);
323}
324
325
326module_init(rcuclassic_trace_init);
327module_exit(rcuclassic_trace_cleanup);
328
329MODULE_AUTHOR("Paul E. McKenney");
330MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
331MODULE_LICENSE("GPL");