xref: /linux/drivers/gpu/drm/xe/xe_range_fence.c (revision b1992c3772e69a6fd0e3fc81cd4d2820c8b6eca0)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2023 Intel Corporation
4  */
5 
6 #include <linux/dma-fence.h>
7 #include <linux/interval_tree_generic.h>
8 #include <linux/slab.h>
9 
10 #include "xe_macros.h"
11 #include "xe_range_fence.h"
12 
13 #define XE_RANGE_TREE_START(_node)	((_node)->start)
14 #define XE_RANGE_TREE_LAST(_node)	((_node)->last)
15 
16 INTERVAL_TREE_DEFINE(struct xe_range_fence, rb, u64, __subtree_last,
17 		     XE_RANGE_TREE_START, XE_RANGE_TREE_LAST, static,
18 		     xe_range_fence_tree);
19 
20 static void
21 xe_range_fence_signal_notify(struct dma_fence *fence, struct dma_fence_cb *cb)
22 {
23 	struct xe_range_fence *rfence = container_of(cb, typeof(*rfence), cb);
24 	struct xe_range_fence_tree *tree = rfence->tree;
25 
26 	llist_add(&rfence->link, &tree->list);
27 }
28 
29 static bool __xe_range_fence_tree_cleanup(struct xe_range_fence_tree *tree)
30 {
31 	struct llist_node *node = llist_del_all(&tree->list);
32 	struct xe_range_fence *rfence, *next;
33 
34 	llist_for_each_entry_safe(rfence, next, node, link) {
35 		xe_range_fence_tree_remove(rfence, &tree->root);
36 		dma_fence_put(rfence->fence);
37 		kfree(rfence);
38 	}
39 
40 	return !!node;
41 }
42 
43 /**
44  * xe_range_fence_insert() - range fence insert
45  * @tree: range fence tree to insert intoi
46  * @rfence: range fence
47  * @ops: range fence ops
48  * @start: start address of range fence
49  * @last: last address of range fence
50  * @fence: dma fence which signals range fence can be removed + freed
51  *
52  * Return: 0 on success, non-zero on failure
53  */
54 int xe_range_fence_insert(struct xe_range_fence_tree *tree,
55 			  struct xe_range_fence *rfence,
56 			  const struct xe_range_fence_ops *ops,
57 			  u64 start, u64 last, struct dma_fence *fence)
58 {
59 	int err = 0;
60 
61 	__xe_range_fence_tree_cleanup(tree);
62 
63 	if (dma_fence_is_signaled(fence))
64 		goto free;
65 
66 	rfence->ops = ops;
67 	rfence->start = start;
68 	rfence->last = last;
69 	rfence->tree = tree;
70 	rfence->fence = dma_fence_get(fence);
71 	err = dma_fence_add_callback(fence, &rfence->cb,
72 				     xe_range_fence_signal_notify);
73 	if (err == -ENOENT) {
74 		dma_fence_put(fence);
75 		err = 0;
76 		goto free;
77 	} else if (err == 0) {
78 		xe_range_fence_tree_insert(rfence, &tree->root);
79 		return 0;
80 	}
81 
82 free:
83 	if (ops->free)
84 		ops->free(rfence);
85 
86 	return err;
87 }
88 
89 static void xe_range_fence_tree_remove_all(struct xe_range_fence_tree *tree)
90 {
91 	struct xe_range_fence *rfence;
92 	bool retry = true;
93 
94 	rfence = xe_range_fence_tree_iter_first(&tree->root, 0, U64_MAX);
95 	while (rfence) {
96 		/* Should be ok with the minimalistic callback */
97 		if (dma_fence_remove_callback(rfence->fence, &rfence->cb))
98 			llist_add(&rfence->link, &tree->list);
99 		rfence = xe_range_fence_tree_iter_next(rfence, 0, U64_MAX);
100 	}
101 
102 	while (retry)
103 		retry = __xe_range_fence_tree_cleanup(tree);
104 }
105 
106 /**
107  * xe_range_fence_tree_init() - Init range fence tree
108  * @tree: range fence tree
109  */
110 void xe_range_fence_tree_init(struct xe_range_fence_tree *tree)
111 {
112 	memset(tree, 0, sizeof(*tree));
113 }
114 
115 /**
116  * xe_range_fence_tree_fini() - Fini range fence tree
117  * @tree: range fence tree
118  */
119 void xe_range_fence_tree_fini(struct xe_range_fence_tree *tree)
120 {
121 	xe_range_fence_tree_remove_all(tree);
122 	XE_WARN_ON(!RB_EMPTY_ROOT(&tree->root.rb_root));
123 }
124 
125 /**
126  * xe_range_fence_tree_first() - range fence tree iterator first
127  * @tree: range fence tree
128  * @start: start address of range fence
129  * @last: last address of range fence
130  *
131  * Return: first range fence found in range or NULL
132  */
133 struct xe_range_fence *
134 xe_range_fence_tree_first(struct xe_range_fence_tree *tree, u64 start,
135 			  u64 last)
136 {
137 	return xe_range_fence_tree_iter_first(&tree->root, start, last);
138 }
139 
140 /**
141  * xe_range_fence_tree_next() - range fence tree iterator next
142  * @rfence: current range fence
143  * @start: start address of range fence
144  * @last: last address of range fence
145  *
146  * Return: next range fence found in range or NULL
147  */
148 struct xe_range_fence *
149 xe_range_fence_tree_next(struct xe_range_fence *rfence, u64 start, u64 last)
150 {
151 	return xe_range_fence_tree_iter_next(rfence, start, last);
152 }
153 
154 static void xe_range_fence_free(struct xe_range_fence *rfence)
155 {
156 	kfree(rfence);
157 }
158 
159 const struct xe_range_fence_ops xe_range_fence_kfree_ops = {
160 	.free = xe_range_fence_free,
161 };
162