sync_debug.c revision 0f0d8406fb9c3c5ed1b1609a0f51c504c5b37aea 
1/*
2 * drivers/base/sync.c
3 *
4 * Copyright (C) 2012 Google, Inc.
5 *
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 */
16
17#include <linux/debugfs.h>
18#include <linux/export.h>
19#include <linux/file.h>
20#include <linux/fs.h>
21#include <linux/kernel.h>
22#include <linux/poll.h>
23#include <linux/sched.h>
24#include <linux/seq_file.h>
25#include <linux/slab.h>
26#include <linux/uaccess.h>
27#include <linux/anon_inodes.h>
28#include "sync.h"
29
30#ifdef CONFIG_DEBUG_FS
31
32static LIST_HEAD(sync_timeline_list_head);
33static DEFINE_SPINLOCK(sync_timeline_list_lock);
34static LIST_HEAD(sync_fence_list_head);
35static DEFINE_SPINLOCK(sync_fence_list_lock);
36
37void sync_timeline_debug_add(struct sync_timeline *obj)
38{
39	unsigned long flags;
40
41	spin_lock_irqsave(&sync_timeline_list_lock, flags);
42	list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
43	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
44}
45
46void sync_timeline_debug_remove(struct sync_timeline *obj)
47{
48	unsigned long flags;
49
50	spin_lock_irqsave(&sync_timeline_list_lock, flags);
51	list_del(&obj->sync_timeline_list);
52	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
53}
54
55void sync_fence_debug_add(struct sync_fence *fence)
56{
57	unsigned long flags;
58
59	spin_lock_irqsave(&sync_fence_list_lock, flags);
60	list_add_tail(&fence->sync_fence_list, &sync_fence_list_head);
61	spin_unlock_irqrestore(&sync_fence_list_lock, flags);
62}
63
64void sync_fence_debug_remove(struct sync_fence *fence)
65{
66	unsigned long flags;
67
68	spin_lock_irqsave(&sync_fence_list_lock, flags);
69	list_del(&fence->sync_fence_list);
70	spin_unlock_irqrestore(&sync_fence_list_lock, flags);
71}
72
73static const char *sync_status_str(int status)
74{
75	if (status == 0)
76		return "signaled";
77	else if (status > 0)
78		return "active";
79	else
80		return "error";
81}
82
83static void sync_print_pt(struct seq_file *s, struct sync_pt *pt, bool fence)
84{
85	int status = 1;
86	struct sync_timeline *parent = sync_pt_parent(pt);
87
88	if (fence_is_signaled_locked(&pt->base))
89		status = pt->base.status;
90
91	seq_printf(s, "  %s%spt %s",
92		   fence ? parent->name : "",
93		   fence ? "_" : "",
94		   sync_status_str(status));
95
96	if (status <= 0) {
97		struct timeval tv = ktime_to_timeval(pt->base.timestamp);
98		seq_printf(s, "@%ld.%06ld", tv.tv_sec, tv.tv_usec);
99	}
100
101	if (parent->ops->timeline_value_str &&
102	    parent->ops->pt_value_str) {
103		char value[64];
104		parent->ops->pt_value_str(pt, value, sizeof(value));
105		seq_printf(s, ": %s", value);
106		if (fence) {
107			parent->ops->timeline_value_str(parent, value,
108						    sizeof(value));
109			seq_printf(s, " / %s", value);
110		}
111	}
112
113	seq_puts(s, "\n");
114}
115
116static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
117{
118	struct list_head *pos;
119	unsigned long flags;
120
121	seq_printf(s, "%s %s", obj->name, obj->ops->driver_name);
122
123	if (obj->ops->timeline_value_str) {
124		char value[64];
125		obj->ops->timeline_value_str(obj, value, sizeof(value));
126		seq_printf(s, ": %s", value);
127	}
128
129	seq_puts(s, "\n");
130
131	spin_lock_irqsave(&obj->child_list_lock, flags);
132	list_for_each(pos, &obj->child_list_head) {
133		struct sync_pt *pt =
134			container_of(pos, struct sync_pt, child_list);
135		sync_print_pt(s, pt, false);
136	}
137	spin_unlock_irqrestore(&obj->child_list_lock, flags);
138}
139
140static void sync_print_fence(struct seq_file *s, struct sync_fence *fence)
141{
142	wait_queue_t *pos;
143	unsigned long flags;
144	int i;
145
146	seq_printf(s, "[%p] %s: %s\n", fence, fence->name,
147		   sync_status_str(atomic_read(&fence->status)));
148
149	for (i = 0; i < fence->num_fences; ++i) {
150		struct sync_pt *pt =
151			container_of(fence->cbs[i].sync_pt,
152				     struct sync_pt, base);
153
154		sync_print_pt(s, pt, true);
155	}
156
157	spin_lock_irqsave(&fence->wq.lock, flags);
158	list_for_each_entry(pos, &fence->wq.task_list, task_list) {
159		struct sync_fence_waiter *waiter;
160
161		if (pos->func != &sync_fence_wake_up_wq)
162			continue;
163
164		waiter = container_of(pos, struct sync_fence_waiter, work);
165
166		seq_printf(s, "waiter %pF\n", waiter->callback);
167	}
168	spin_unlock_irqrestore(&fence->wq.lock, flags);
169}
170
171static int sync_debugfs_show(struct seq_file *s, void *unused)
172{
173	unsigned long flags;
174	struct list_head *pos;
175
176	seq_puts(s, "objs:\n--------------\n");
177
178	spin_lock_irqsave(&sync_timeline_list_lock, flags);
179	list_for_each(pos, &sync_timeline_list_head) {
180		struct sync_timeline *obj =
181			container_of(pos, struct sync_timeline,
182				     sync_timeline_list);
183
184		sync_print_obj(s, obj);
185		seq_puts(s, "\n");
186	}
187	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
188
189	seq_puts(s, "fences:\n--------------\n");
190
191	spin_lock_irqsave(&sync_fence_list_lock, flags);
192	list_for_each(pos, &sync_fence_list_head) {
193		struct sync_fence *fence =
194			container_of(pos, struct sync_fence, sync_fence_list);
195
196		sync_print_fence(s, fence);
197		seq_puts(s, "\n");
198	}
199	spin_unlock_irqrestore(&sync_fence_list_lock, flags);
200	return 0;
201}
202
203static int sync_debugfs_open(struct inode *inode, struct file *file)
204{
205	return single_open(file, sync_debugfs_show, inode->i_private);
206}
207
208static const struct file_operations sync_debugfs_fops = {
209	.open           = sync_debugfs_open,
210	.read           = seq_read,
211	.llseek         = seq_lseek,
212	.release        = single_release,
213};
214
215static __init int sync_debugfs_init(void)
216{
217	debugfs_create_file("sync", S_IRUGO, NULL, NULL, &sync_debugfs_fops);
218	return 0;
219}
220late_initcall(sync_debugfs_init);
221
222#define DUMP_CHUNK 256
223static char sync_dump_buf[64 * 1024];
224void sync_dump(void)
225{
226	struct seq_file s = {
227		.buf = sync_dump_buf,
228		.size = sizeof(sync_dump_buf) - 1,
229	};
230	int i;
231
232	sync_debugfs_show(&s, NULL);
233
234	for (i = 0; i < s.count; i += DUMP_CHUNK) {
235		if ((s.count - i) > DUMP_CHUNK) {
236			char c = s.buf[i + DUMP_CHUNK];
237			s.buf[i + DUMP_CHUNK] = 0;
238			pr_cont("%s", s.buf + i);
239			s.buf[i + DUMP_CHUNK] = c;
240		} else {
241			s.buf[s.count] = 0;
242			pr_cont("%s", s.buf + i);
243		}
244	}
245}
246
247#endif
248