xref: /linux/drivers/dma-buf/sync_debug.c (revision 73b7fd4b209263a92726daca6453a37ecb89eb9d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Sync File validation framework and debug information
4  *
5  * Copyright (C) 2012 Google, Inc.
6  */
7 
8 #include <linux/debugfs.h>
9 #include "sync_debug.h"
10 
11 static struct dentry *dbgfs;
12 
13 static LIST_HEAD(sync_timeline_list_head);
14 static DEFINE_SPINLOCK(sync_timeline_list_lock);
15 static LIST_HEAD(sync_file_list_head);
16 static DEFINE_SPINLOCK(sync_file_list_lock);
17 
18 void sync_timeline_debug_add(struct sync_timeline *obj)
19 {
20 	unsigned long flags;
21 
22 	spin_lock_irqsave(&sync_timeline_list_lock, flags);
23 	list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
24 	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
25 }
26 
27 void sync_timeline_debug_remove(struct sync_timeline *obj)
28 {
29 	unsigned long flags;
30 
31 	spin_lock_irqsave(&sync_timeline_list_lock, flags);
32 	list_del(&obj->sync_timeline_list);
33 	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
34 }
35 
36 void sync_file_debug_add(struct sync_file *sync_file)
37 {
38 	unsigned long flags;
39 
40 	spin_lock_irqsave(&sync_file_list_lock, flags);
41 	list_add_tail(&sync_file->sync_file_list, &sync_file_list_head);
42 	spin_unlock_irqrestore(&sync_file_list_lock, flags);
43 }
44 
45 void sync_file_debug_remove(struct sync_file *sync_file)
46 {
47 	unsigned long flags;
48 
49 	spin_lock_irqsave(&sync_file_list_lock, flags);
50 	list_del(&sync_file->sync_file_list);
51 	spin_unlock_irqrestore(&sync_file_list_lock, flags);
52 }
53 
54 static const char *sync_status_str(int status)
55 {
56 	if (status < 0)
57 		return "error";
58 
59 	if (status > 0)
60 		return "signaled";
61 
62 	return "active";
63 }
64 
65 static void sync_print_fence(struct seq_file *s,
66 			     struct dma_fence *fence, bool show)
67 {
68 	struct sync_timeline *parent = dma_fence_parent(fence);
69 	int status;
70 
71 	status = dma_fence_get_status_locked(fence);
72 
73 	seq_printf(s, "  %s%sfence %s",
74 		   show ? parent->name : "",
75 		   show ? "_" : "",
76 		   sync_status_str(status));
77 
78 	if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags)) {
79 		struct timespec64 ts64 =
80 			ktime_to_timespec64(fence->timestamp);
81 
82 		seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
83 	}
84 
85 	seq_printf(s, ": %lld", fence->seqno);
86 	seq_printf(s, " / %d", parent->value);
87 	seq_putc(s, '\n');
88 }
89 
90 static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
91 {
92 	struct list_head *pos;
93 
94 	seq_printf(s, "%s: %d\n", obj->name, obj->value);
95 
96 	spin_lock(&obj->lock); /* Caller already disabled IRQ. */
97 	list_for_each(pos, &obj->pt_list) {
98 		struct sync_pt *pt = container_of(pos, struct sync_pt, link);
99 		sync_print_fence(s, &pt->base, false);
100 	}
101 	spin_unlock(&obj->lock);
102 }
103 
104 static void sync_print_sync_file(struct seq_file *s,
105 				  struct sync_file *sync_file)
106 {
107 	char buf[128];
108 	int i;
109 
110 	seq_printf(s, "[%p] %s: %s\n", sync_file,
111 		   sync_file_get_name(sync_file, buf, sizeof(buf)),
112 		   sync_status_str(dma_fence_get_status(sync_file->fence)));
113 
114 	if (dma_fence_is_array(sync_file->fence)) {
115 		struct dma_fence_array *array = to_dma_fence_array(sync_file->fence);
116 
117 		for (i = 0; i < array->num_fences; ++i)
118 			sync_print_fence(s, array->fences[i], true);
119 	} else {
120 		sync_print_fence(s, sync_file->fence, true);
121 	}
122 }
123 
124 static int sync_info_debugfs_show(struct seq_file *s, void *unused)
125 {
126 	struct list_head *pos;
127 
128 	seq_puts(s, "objs:\n--------------\n");
129 
130 	spin_lock_irq(&sync_timeline_list_lock);
131 	list_for_each(pos, &sync_timeline_list_head) {
132 		struct sync_timeline *obj =
133 			container_of(pos, struct sync_timeline,
134 				     sync_timeline_list);
135 
136 		sync_print_obj(s, obj);
137 		seq_putc(s, '\n');
138 	}
139 	spin_unlock_irq(&sync_timeline_list_lock);
140 
141 	seq_puts(s, "fences:\n--------------\n");
142 
143 	spin_lock_irq(&sync_file_list_lock);
144 	list_for_each(pos, &sync_file_list_head) {
145 		struct sync_file *sync_file =
146 			container_of(pos, struct sync_file, sync_file_list);
147 
148 		sync_print_sync_file(s, sync_file);
149 		seq_putc(s, '\n');
150 	}
151 	spin_unlock_irq(&sync_file_list_lock);
152 	return 0;
153 }
154 
155 DEFINE_SHOW_ATTRIBUTE(sync_info_debugfs);
156 
157 static __init int sync_debugfs_init(void)
158 {
159 	dbgfs = debugfs_create_dir("sync", NULL);
160 
161 	/*
162 	 * The debugfs files won't ever get removed and thus, there is
163 	 * no need to protect it against removal races. The use of
164 	 * debugfs_create_file_unsafe() is actually safe here.
165 	 */
166 	debugfs_create_file_unsafe("info", 0444, dbgfs, NULL,
167 				   &sync_info_debugfs_fops);
168 	debugfs_create_file_unsafe("sw_sync", 0644, dbgfs, NULL,
169 				   &sw_sync_debugfs_fops);
170 
171 	return 0;
172 }
173 late_initcall(sync_debugfs_init);
174