xref: /dflybsd-src/sys/dev/drm/i915/i915_gem_evict.c (revision 5f39c7e70ca0960d1868c75a449064df712dbb10)
1 /*
2  * Copyright © 2008-2010 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  * Authors:
24  *    Eric Anholt <eric@anholt.net>
25  *    Chris Wilson <chris@chris-wilson.co.uuk>
26  *
27  * $FreeBSD: src/sys/dev/drm2/i915/i915_gem_evict.c,v 1.1 2012/05/22 11:07:44 kib Exp $
28  */
29 
30 #include <drm/drmP.h>
31 #include <drm/i915_drm.h>
32 #include "i915_drv.h"
33 
34 static bool
35 mark_free(struct drm_i915_gem_object *obj, struct list_head *unwind)
36 {
37 	if (obj->pin_count)
38 		return false;
39 
40 	list_add(&obj->exec_list, unwind);
41 	return drm_mm_scan_add_block(obj->gtt_space);
42 }
43 
44 int
45 i915_gem_evict_something(struct drm_device *dev, int min_size,
46 			 unsigned alignment, bool mappable)
47 {
48 	drm_i915_private_t *dev_priv = dev->dev_private;
49 	struct list_head eviction_list, unwind_list;
50 	struct drm_i915_gem_object *obj;
51 	int ret = 0;
52 	int cache_level = 0;
53 
54 	/*
55 	 * The goal is to evict objects and amalgamate space in LRU order.
56 	 * The oldest idle objects reside on the inactive list, which is in
57 	 * retirement order. The next objects to retire are those on the (per
58 	 * ring) active list that do not have an outstanding flush. Once the
59 	 * hardware reports completion (the seqno is updated after the
60 	 * batchbuffer has been finished) the clean buffer objects would
61 	 * be retired to the inactive list. Any dirty objects would be added
62 	 * to the tail of the flushing list. So after processing the clean
63 	 * active objects we need to emit a MI_FLUSH to retire the flushing
64 	 * list, hence the retirement order of the flushing list is in
65 	 * advance of the dirty objects on the active lists.
66 	 *
67 	 * The retirement sequence is thus:
68 	 *   1. Inactive objects (already retired)
69 	 *   2. Clean active objects
70 	 *   3. Flushing list
71 	 *   4. Dirty active objects.
72 	 *
73 	 * On each list, the oldest objects lie at the HEAD with the freshest
74 	 * object on the TAIL.
75 	 */
76 
77 	INIT_LIST_HEAD(&unwind_list);
78 	if (mappable)
79 		drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space,
80 					    min_size, alignment, cache_level,
81 					    0, dev_priv->mm.gtt_mappable_end);
82 	else
83 		drm_mm_init_scan(&dev_priv->mm.gtt_space,
84 				 min_size, alignment, cache_level);
85 
86 	/* First see if there is a large enough contiguous idle region... */
87 	list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
88 		if (mark_free(obj, &unwind_list))
89 			goto found;
90 	}
91 
92 	/* Now merge in the soon-to-be-expired objects... */
93 	list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
94 		/* Does the object require an outstanding flush? */
95 		if (obj->base.write_domain || obj->pin_count)
96 			continue;
97 
98 		if (mark_free(obj, &unwind_list))
99 			goto found;
100 	}
101 
102 	/* Finally add anything with a pending flush (in order of retirement) */
103 	list_for_each_entry(obj, &dev_priv->mm.flushing_list, mm_list) {
104 		if (obj->pin_count)
105 			continue;
106 
107 		if (mark_free(obj, &unwind_list))
108 			goto found;
109 	}
110 	list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
111 		if (!obj->base.write_domain || obj->pin_count)
112 			continue;
113 
114 		if (mark_free(obj, &unwind_list))
115 			goto found;
116 	}
117 
118 	/* Nothing found, clean up and bail out! */
119 	while (!list_empty(&unwind_list)) {
120 		obj = list_first_entry(&unwind_list,
121 				       struct drm_i915_gem_object,
122 				       exec_list);
123 
124 		ret = drm_mm_scan_remove_block(obj->gtt_space);
125 		KASSERT(ret == 0, ("drm_mm_scan_remove_block failed %d", ret));
126 
127 		list_del_init(&obj->exec_list);
128 	}
129 
130 	/* We expect the caller to unpin, evict all and try again, or give up.
131 	 * So calling i915_gem_evict_everything() is unnecessary.
132 	 */
133 	return -ENOSPC;
134 
135 found:
136 	/* drm_mm doesn't allow any other other operations while
137 	 * scanning, therefore store to be evicted objects on a
138 	 * temporary list. */
139 	INIT_LIST_HEAD(&eviction_list);
140 	while (!list_empty(&unwind_list)) {
141 		obj = list_first_entry(&unwind_list,
142 				       struct drm_i915_gem_object,
143 				       exec_list);
144 		if (drm_mm_scan_remove_block(obj->gtt_space)) {
145 			list_move(&obj->exec_list, &eviction_list);
146 			drm_gem_object_reference(&obj->base);
147 			continue;
148 		}
149 		list_del_init(&obj->exec_list);
150 	}
151 
152 	/* Unbinding will emit any required flushes */
153 	while (!list_empty(&eviction_list)) {
154 		obj = list_first_entry(&eviction_list,
155 				       struct drm_i915_gem_object,
156 				       exec_list);
157 		if (ret == 0)
158 			ret = i915_gem_object_unbind(obj);
159 
160 		list_del_init(&obj->exec_list);
161 		drm_gem_object_unreference(&obj->base);
162 	}
163 
164 	return ret;
165 }
166 
167 int
168 i915_gem_evict_everything(struct drm_device *dev, bool purgeable_only)
169 {
170 	drm_i915_private_t *dev_priv = dev->dev_private;
171 	int ret;
172 	bool lists_empty;
173 
174 	lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
175 		       list_empty(&dev_priv->mm.flushing_list) &&
176 		       list_empty(&dev_priv->mm.active_list));
177 	if (lists_empty)
178 		return -ENOSPC;
179 
180 	/* Flush everything (on to the inactive lists) and evict */
181 	ret = i915_gpu_idle(dev);
182 	if (ret)
183 		return ret;
184 
185 	KASSERT(list_empty(&dev_priv->mm.flushing_list),
186 	    ("flush list not empty"));
187 
188 	return i915_gem_evict_inactive(dev, purgeable_only);
189 }
190 
191 /** Unbinds all inactive objects. */
192 int
193 i915_gem_evict_inactive(struct drm_device *dev, bool purgeable_only)
194 {
195 	drm_i915_private_t *dev_priv = dev->dev_private;
196 	struct drm_i915_gem_object *obj, *next;
197 
198 	list_for_each_entry_safe(obj, next,
199 				 &dev_priv->mm.inactive_list, mm_list) {
200 		if (!purgeable_only || obj->madv != I915_MADV_WILLNEED) {
201 			int ret = i915_gem_object_unbind(obj);
202 			if (ret)
203 				return ret;
204 		}
205 	}
206 
207 	return 0;
208 }
209