1 /*
2 * SPDX-License-Identifier: MIT
3 *
4 * Copyright © 2016-2018 Intel Corporation
5 */
6
7 #include "i915_drv.h"
8
9 #include "i915_timeline.h"
10 #include "i915_syncmap.h"
11
i915_timeline_init(struct drm_i915_private * i915,struct i915_timeline * timeline,const char * name)12 void i915_timeline_init(struct drm_i915_private *i915,
13 struct i915_timeline *timeline,
14 const char *name)
15 {
16 lockdep_assert_held(&i915->drm.struct_mutex);
17
18 /*
19 * Ideally we want a set of engines on a single leaf as we expect
20 * to mostly be tracking synchronisation between engines. It is not
21 * a huge issue if this is not the case, but we may want to mitigate
22 * any page crossing penalties if they become an issue.
23 */
24 BUILD_BUG_ON(KSYNCMAP < I915_NUM_ENGINES);
25
26 timeline->name = name;
27
28 list_add(&timeline->link, &i915->gt.timelines);
29
30 /* Called during early_init before we know how many engines there are */
31
32 timeline->fence_context = dma_fence_context_alloc(1);
33
34 spin_lock_init(&timeline->lock);
35
36 init_request_active(&timeline->last_request, NULL);
37 INIT_LIST_HEAD(&timeline->requests);
38
39 i915_syncmap_init(&timeline->sync);
40 }
41
42 /**
43 * i915_timelines_park - called when the driver idles
44 * @i915: the drm_i915_private device
45 *
46 * When the driver is completely idle, we know that all of our sync points
47 * have been signaled and our tracking is then entirely redundant. Any request
48 * to wait upon an older sync point will be completed instantly as we know
49 * the fence is signaled and therefore we will not even look them up in the
50 * sync point map.
51 */
i915_timelines_park(struct drm_i915_private * i915)52 void i915_timelines_park(struct drm_i915_private *i915)
53 {
54 struct i915_timeline *timeline;
55
56 lockdep_assert_held(&i915->drm.struct_mutex);
57
58 list_for_each_entry(timeline, &i915->gt.timelines, link) {
59 /*
60 * All known fences are completed so we can scrap
61 * the current sync point tracking and start afresh,
62 * any attempt to wait upon a previous sync point
63 * will be skipped as the fence was signaled.
64 */
65 i915_syncmap_free(&timeline->sync);
66 }
67 }
68
i915_timeline_fini(struct i915_timeline * timeline)69 void i915_timeline_fini(struct i915_timeline *timeline)
70 {
71 GEM_BUG_ON(!list_empty(&timeline->requests));
72
73 i915_syncmap_free(&timeline->sync);
74
75 list_del(&timeline->link);
76 }
77
78 struct i915_timeline *
i915_timeline_create(struct drm_i915_private * i915,const char * name)79 i915_timeline_create(struct drm_i915_private *i915, const char *name)
80 {
81 struct i915_timeline *timeline;
82
83 timeline = kzalloc(sizeof(*timeline), GFP_KERNEL);
84 if (!timeline)
85 return ERR_PTR(-ENOMEM);
86
87 i915_timeline_init(i915, timeline, name);
88 kref_init(&timeline->kref);
89
90 return timeline;
91 }
92
__i915_timeline_free(struct kref * kref)93 void __i915_timeline_free(struct kref *kref)
94 {
95 struct i915_timeline *timeline =
96 container_of(kref, typeof(*timeline), kref);
97
98 i915_timeline_fini(timeline);
99 kfree(timeline);
100 }
101
102 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
103 #include "selftests/mock_timeline.c"
104 #include "selftests/i915_timeline.c"
105 #endif
106
