xref: /NextBSD/sys/dev/drm2/i915/i915_gem_evict.c (revision 287e3b14e9552995def1802ec9c5034f4adf28ec)
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  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <dev/drm2/drmP.h>
33 #include <dev/drm2/drm.h>
34 #include <dev/drm2/i915/i915_drm.h>
35 #include <dev/drm2/i915/i915_drv.h>
36 
37 static bool
mark_free(struct drm_i915_gem_object * obj,struct list_head * unwind)38 mark_free(struct drm_i915_gem_object *obj, struct list_head *unwind)
39 {
40 	if (obj->pin_count)
41 		return false;
42 
43 	list_add(&obj->exec_list, unwind);
44 	return drm_mm_scan_add_block(obj->gtt_space);
45 }
46 
47 int
i915_gem_evict_something(struct drm_device * dev,int min_size,unsigned alignment,bool mappable)48 i915_gem_evict_something(struct drm_device *dev, int min_size,
49 			 unsigned alignment, bool mappable)
50 {
51 	drm_i915_private_t *dev_priv = dev->dev_private;
52 	struct list_head eviction_list, unwind_list;
53 	struct drm_i915_gem_object *obj;
54 	int ret = 0;
55 
56 	CTR4(KTR_DRM, "evict_something %p %d %u %d", dev, min_size,
57 	    alignment, mappable);
58 
59 	/*
60 	 * The goal is to evict objects and amalgamate space in LRU order.
61 	 * The oldest idle objects reside on the inactive list, which is in
62 	 * retirement order. The next objects to retire are those on the (per
63 	 * ring) active list that do not have an outstanding flush. Once the
64 	 * hardware reports completion (the seqno is updated after the
65 	 * batchbuffer has been finished) the clean buffer objects would
66 	 * be retired to the inactive list. Any dirty objects would be added
67 	 * to the tail of the flushing list. So after processing the clean
68 	 * active objects we need to emit a MI_FLUSH to retire the flushing
69 	 * list, hence the retirement order of the flushing list is in
70 	 * advance of the dirty objects on the active lists.
71 	 *
72 	 * The retirement sequence is thus:
73 	 *   1. Inactive objects (already retired)
74 	 *   2. Clean active objects
75 	 *   3. Flushing list
76 	 *   4. Dirty active objects.
77 	 *
78 	 * On each list, the oldest objects lie at the HEAD with the freshest
79 	 * object on the TAIL.
80 	 */
81 
82 	INIT_LIST_HEAD(&unwind_list);
83 	if (mappable)
84 		drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space, min_size,
85 					    alignment, 0, 0,
86 					    dev_priv->mm.gtt_mappable_end);
87 	else
88 		drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment, 0);
89 
90 	/* First see if there is a large enough contiguous idle region... */
91 	list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
92 		if (mark_free(obj, &unwind_list))
93 			goto found;
94 	}
95 
96 	/* Now merge in the soon-to-be-expired objects... */
97 	list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
98 		/* Does the object require an outstanding flush? */
99 		if (obj->base.write_domain)
100 			continue;
101 
102 		if (mark_free(obj, &unwind_list))
103 			goto found;
104 	}
105 
106 	/* Finally add anything with a pending flush (in order of retirement) */
107 	list_for_each_entry(obj, &dev_priv->mm.flushing_list, mm_list) {
108 		if (mark_free(obj, &unwind_list))
109 			goto found;
110 	}
111 	list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
112 		if (!obj->base.write_domain)
113 			continue;
114 
115 		if (mark_free(obj, &unwind_list))
116 			goto found;
117 	}
118 
119 	/* Nothing found, clean up and bail out! */
120 	while (!list_empty(&unwind_list)) {
121 		obj = list_first_entry(&unwind_list,
122 				       struct drm_i915_gem_object,
123 				       exec_list);
124 
125 		ret = drm_mm_scan_remove_block(obj->gtt_space);
126 		KASSERT(ret == 0, ("drm_mm_scan_remove_block failed %d", ret));
127 
128 		list_del_init(&obj->exec_list);
129 	}
130 
131 	/* We expect the caller to unpin, evict all and try again, or give up.
132 	 * So calling i915_gem_evict_everything() is unnecessary.
133 	 */
134 	return -ENOSPC;
135 
136 found:
137 	/* drm_mm doesn't allow any other other operations while
138 	 * scanning, therefore store to be evicted objects on a
139 	 * temporary list. */
140 	INIT_LIST_HEAD(&eviction_list);
141 	while (!list_empty(&unwind_list)) {
142 		obj = list_first_entry(&unwind_list,
143 				       struct drm_i915_gem_object,
144 				       exec_list);
145 		if (drm_mm_scan_remove_block(obj->gtt_space)) {
146 			list_move(&obj->exec_list, &eviction_list);
147 			drm_gem_object_reference(&obj->base);
148 			continue;
149 		}
150 		list_del_init(&obj->exec_list);
151 	}
152 
153 	/* Unbinding will emit any required flushes */
154 	while (!list_empty(&eviction_list)) {
155 		obj = list_first_entry(&eviction_list,
156 				       struct drm_i915_gem_object,
157 				       exec_list);
158 		if (ret == 0)
159 			ret = i915_gem_object_unbind(obj);
160 
161 		list_del_init(&obj->exec_list);
162 		drm_gem_object_unreference(&obj->base);
163 	}
164 
165 	return ret;
166 }
167 
168 int
i915_gem_evict_everything(struct drm_device * dev,bool purgeable_only)169 i915_gem_evict_everything(struct drm_device *dev, bool purgeable_only)
170 {
171 	drm_i915_private_t *dev_priv = dev->dev_private;
172 	struct drm_i915_gem_object *obj, *next;
173 	bool lists_empty;
174 	int ret;
175 
176 	lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
177 		       list_empty(&dev_priv->mm.flushing_list) &&
178 		       list_empty(&dev_priv->mm.active_list));
179 	if (lists_empty)
180 		return -ENOSPC;
181 
182 	CTR2(KTR_DRM, "evict_everything %p %d", dev, purgeable_only);
183 
184 	/* The gpu_idle will flush everything in the write domain to the
185 	 * active list. Then we must move everything off the active list
186 	 * with retire requests.
187 	 */
188 	ret = i915_gpu_idle(dev);
189 	if (ret)
190 		return ret;
191 
192 	i915_gem_retire_requests(dev);
193 
194 	KASSERT(list_empty(&dev_priv->mm.flushing_list),
195 	    ("flush list not empty"));
196 
197 	/* Having flushed everything, unbind() should never raise an error */
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 			if (obj->pin_count == 0)
202 				i915_gem_object_unbind(obj);
203 		}
204 	}
205 
206 	return 0;
207 }
208