xref: /linux/drivers/dma-buf/sync_debug.c (revision 32786fdc9506aeba98278c1844d4bfb766863832)
1 /*
2  * Sync File validation framework and debug information
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 "sync_debug.h"
19 
20 static struct dentry *dbgfs;
21 
22 static LIST_HEAD(sync_timeline_list_head);
23 static DEFINE_SPINLOCK(sync_timeline_list_lock);
24 static LIST_HEAD(sync_file_list_head);
25 static DEFINE_SPINLOCK(sync_file_list_lock);
26 
27 void sync_timeline_debug_add(struct sync_timeline *obj)
28 {
29 	unsigned long flags;
30 
31 	spin_lock_irqsave(&sync_timeline_list_lock, flags);
32 	list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
33 	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
34 }
35 
36 void sync_timeline_debug_remove(struct sync_timeline *obj)
37 {
38 	unsigned long flags;
39 
40 	spin_lock_irqsave(&sync_timeline_list_lock, flags);
41 	list_del(&obj->sync_timeline_list);
42 	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
43 }
44 
45 void sync_file_debug_add(struct sync_file *sync_file)
46 {
47 	unsigned long flags;
48 
49 	spin_lock_irqsave(&sync_file_list_lock, flags);
50 	list_add_tail(&sync_file->sync_file_list, &sync_file_list_head);
51 	spin_unlock_irqrestore(&sync_file_list_lock, flags);
52 }
53 
54 void sync_file_debug_remove(struct sync_file *sync_file)
55 {
56 	unsigned long flags;
57 
58 	spin_lock_irqsave(&sync_file_list_lock, flags);
59 	list_del(&sync_file->sync_file_list);
60 	spin_unlock_irqrestore(&sync_file_list_lock, flags);
61 }
62 
63 static const char *sync_status_str(int status)
64 {
65 	if (status == 0)
66 		return "signaled";
67 
68 	if (status > 0)
69 		return "active";
70 
71 	return "error";
72 }
73 
74 static void sync_print_fence(struct seq_file *s,
75 			     struct dma_fence *fence, bool show)
76 {
77 	int status = 1;
78 	struct sync_timeline *parent = dma_fence_parent(fence);
79 
80 	if (dma_fence_is_signaled_locked(fence))
81 		status = fence->status;
82 
83 	seq_printf(s, "  %s%sfence %s",
84 		   show ? parent->name : "",
85 		   show ? "_" : "",
86 		   sync_status_str(status));
87 
88 	if (status <= 0) {
89 		struct timespec64 ts64 =
90 			ktime_to_timespec64(fence->timestamp);
91 
92 		seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
93 	}
94 
95 	if (fence->ops->timeline_value_str &&
96 		fence->ops->fence_value_str) {
97 		char value[64];
98 		bool success;
99 
100 		fence->ops->fence_value_str(fence, value, sizeof(value));
101 		success = strlen(value);
102 
103 		if (success) {
104 			seq_printf(s, ": %s", value);
105 
106 			fence->ops->timeline_value_str(fence, value,
107 						       sizeof(value));
108 
109 			if (strlen(value))
110 				seq_printf(s, " / %s", value);
111 		}
112 	}
113 
114 	seq_puts(s, "\n");
115 }
116 
117 static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
118 {
119 	struct list_head *pos;
120 	unsigned long flags;
121 
122 	seq_printf(s, "%s: %d\n", obj->name, obj->value);
123 
124 	spin_lock_irqsave(&obj->child_list_lock, flags);
125 	list_for_each(pos, &obj->child_list_head) {
126 		struct sync_pt *pt =
127 			container_of(pos, struct sync_pt, child_list);
128 		sync_print_fence(s, &pt->base, false);
129 	}
130 	spin_unlock_irqrestore(&obj->child_list_lock, flags);
131 }
132 
133 static void sync_print_sync_file(struct seq_file *s,
134 				  struct sync_file *sync_file)
135 {
136 	int i;
137 
138 	seq_printf(s, "[%p] %s: %s\n", sync_file, sync_file->name,
139 		   sync_status_str(!dma_fence_is_signaled(sync_file->fence)));
140 
141 	if (dma_fence_is_array(sync_file->fence)) {
142 		struct dma_fence_array *array = to_dma_fence_array(sync_file->fence);
143 
144 		for (i = 0; i < array->num_fences; ++i)
145 			sync_print_fence(s, array->fences[i], true);
146 	} else {
147 		sync_print_fence(s, sync_file->fence, true);
148 	}
149 }
150 
151 static int sync_debugfs_show(struct seq_file *s, void *unused)
152 {
153 	unsigned long flags;
154 	struct list_head *pos;
155 
156 	seq_puts(s, "objs:\n--------------\n");
157 
158 	spin_lock_irqsave(&sync_timeline_list_lock, flags);
159 	list_for_each(pos, &sync_timeline_list_head) {
160 		struct sync_timeline *obj =
161 			container_of(pos, struct sync_timeline,
162 				     sync_timeline_list);
163 
164 		sync_print_obj(s, obj);
165 		seq_puts(s, "\n");
166 	}
167 	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
168 
169 	seq_puts(s, "fences:\n--------------\n");
170 
171 	spin_lock_irqsave(&sync_file_list_lock, flags);
172 	list_for_each(pos, &sync_file_list_head) {
173 		struct sync_file *sync_file =
174 			container_of(pos, struct sync_file, sync_file_list);
175 
176 		sync_print_sync_file(s, sync_file);
177 		seq_puts(s, "\n");
178 	}
179 	spin_unlock_irqrestore(&sync_file_list_lock, flags);
180 	return 0;
181 }
182 
183 static int sync_info_debugfs_open(struct inode *inode, struct file *file)
184 {
185 	return single_open(file, sync_debugfs_show, inode->i_private);
186 }
187 
188 static const struct file_operations sync_info_debugfs_fops = {
189 	.open           = sync_info_debugfs_open,
190 	.read           = seq_read,
191 	.llseek         = seq_lseek,
192 	.release        = single_release,
193 };
194 
195 static __init int sync_debugfs_init(void)
196 {
197 	dbgfs = debugfs_create_dir("sync", NULL);
198 
199 	/*
200 	 * The debugfs files won't ever get removed and thus, there is
201 	 * no need to protect it against removal races. The use of
202 	 * debugfs_create_file_unsafe() is actually safe here.
203 	 */
204 	debugfs_create_file_unsafe("info", 0444, dbgfs, NULL,
205 				   &sync_info_debugfs_fops);
206 	debugfs_create_file_unsafe("sw_sync", 0644, dbgfs, NULL,
207 				   &sw_sync_debugfs_fops);
208 
209 	return 0;
210 }
211 late_initcall(sync_debugfs_init);
212 
213 #define DUMP_CHUNK 256
214 static char sync_dump_buf[64 * 1024];
215 void sync_dump(void)
216 {
217 	struct seq_file s = {
218 		.buf = sync_dump_buf,
219 		.size = sizeof(sync_dump_buf) - 1,
220 	};
221 	int i;
222 
223 	sync_debugfs_show(&s, NULL);
224 
225 	for (i = 0; i < s.count; i += DUMP_CHUNK) {
226 		if ((s.count - i) > DUMP_CHUNK) {
227 			char c = s.buf[i + DUMP_CHUNK];
228 
229 			s.buf[i + DUMP_CHUNK] = 0;
230 			pr_cont("%s", s.buf + i);
231 			s.buf[i + DUMP_CHUNK] = c;
232 		} else {
233 			s.buf[s.count] = 0;
234 			pr_cont("%s", s.buf + i);
235 		}
236 	}
237 }
238