1 /*
2 * Copyright © 2017 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 */
24
25 #include "lib_sw_fence.h"
26
27 /* Small library of different fence types useful for writing tests */
28
29 static int __i915_sw_fence_call
nop_fence_notify(struct i915_sw_fence * fence,enum i915_sw_fence_notify state)30 nop_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
31 {
32 return NOTIFY_DONE;
33 }
34
__onstack_fence_init(struct i915_sw_fence * fence,const char * name,struct lock_class_key * key)35 void __onstack_fence_init(struct i915_sw_fence *fence,
36 const char *name,
37 struct lock_class_key *key)
38 {
39 debug_fence_init_onstack(fence);
40
41 __init_waitqueue_head(&fence->wait, name, key);
42 atomic_set(&fence->pending, 1);
43 fence->error = 0;
44 fence->flags = (unsigned long)nop_fence_notify;
45 }
46
onstack_fence_fini(struct i915_sw_fence * fence)47 void onstack_fence_fini(struct i915_sw_fence *fence)
48 {
49 if (!fence->flags)
50 return;
51
52 i915_sw_fence_commit(fence);
53 i915_sw_fence_fini(fence);
54 }
55
timed_fence_wake(struct timer_list * t)56 static void timed_fence_wake(struct timer_list *t)
57 {
58 struct timed_fence *tf = from_timer(tf, t, timer);
59
60 i915_sw_fence_commit(&tf->fence);
61 }
62
timed_fence_init(struct timed_fence * tf,unsigned long expires)63 void timed_fence_init(struct timed_fence *tf, unsigned long expires)
64 {
65 onstack_fence_init(&tf->fence);
66
67 timer_setup_on_stack(&tf->timer, timed_fence_wake, 0);
68
69 if (time_after(expires, jiffies))
70 mod_timer(&tf->timer, expires);
71 else
72 i915_sw_fence_commit(&tf->fence);
73 }
74
timed_fence_fini(struct timed_fence * tf)75 void timed_fence_fini(struct timed_fence *tf)
76 {
77 if (del_timer_sync(&tf->timer))
78 i915_sw_fence_commit(&tf->fence);
79
80 destroy_timer_on_stack(&tf->timer);
81 i915_sw_fence_fini(&tf->fence);
82 }
83
84 struct heap_fence {
85 struct i915_sw_fence fence;
86 union {
87 struct kref ref;
88 struct rcu_head rcu;
89 };
90 };
91
92 static int __i915_sw_fence_call
heap_fence_notify(struct i915_sw_fence * fence,enum i915_sw_fence_notify state)93 heap_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
94 {
95 struct heap_fence *h = container_of(fence, typeof(*h), fence);
96
97 switch (state) {
98 case FENCE_COMPLETE:
99 break;
100
101 case FENCE_FREE:
102 heap_fence_put(&h->fence);
103 }
104
105 return NOTIFY_DONE;
106 }
107
heap_fence_create(gfp_t gfp)108 struct i915_sw_fence *heap_fence_create(gfp_t gfp)
109 {
110 struct heap_fence *h;
111
112 h = kmalloc(sizeof(*h), gfp);
113 if (!h)
114 return NULL;
115
116 i915_sw_fence_init(&h->fence, heap_fence_notify);
117 refcount_set(&h->ref.refcount, 2);
118
119 return &h->fence;
120 }
121
heap_fence_release(struct kref * ref)122 static void heap_fence_release(struct kref *ref)
123 {
124 struct heap_fence *h = container_of(ref, typeof(*h), ref);
125
126 i915_sw_fence_fini(&h->fence);
127
128 kfree_rcu(h, rcu);
129 }
130
heap_fence_put(struct i915_sw_fence * fence)131 void heap_fence_put(struct i915_sw_fence *fence)
132 {
133 struct heap_fence *h = container_of(fence, typeof(*h), fence);
134
135 kref_put(&h->ref, heap_fence_release);
136 }
137