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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 "drmP.h"
30#include "drm.h"
31#include "i915_drv.h"
32#include "i915_drm.h"
33#include "i915_trace.h"
34
35static bool
36mark_free(struct drm_i915_gem_object *obj, struct list_head *unwind)
37{
38 list_add(&obj->exec_list, unwind);
39 drm_gem_object_reference(&obj->base);
40 return drm_mm_scan_add_block(obj->gtt_space);
41}
42
43int
44i915_gem_evict_something(struct drm_device *dev, int min_size,
45 unsigned alignment, bool mappable)
46{
47 drm_i915_private_t *dev_priv = dev->dev_private;
48 struct list_head eviction_list, unwind_list;
49 struct drm_i915_gem_object *obj;
50 int ret = 0;
51
52 i915_gem_retire_requests(dev);
53
54 /* Re-check for free space after retiring requests */
55 if (mappable) {
56 if (drm_mm_search_free_in_range(&dev_priv->mm.gtt_space,
57 min_size, alignment, 0,
58 dev_priv->mm.gtt_mappable_end,
59 0))
60 return 0;
61 } else {
62 if (drm_mm_search_free(&dev_priv->mm.gtt_space,
63 min_size, alignment, 0))
64 return 0;
65 }
66
67 trace_i915_gem_evict(dev, min_size, alignment, mappable);
68
69 /*
70 * The goal is to evict objects and amalgamate space in LRU order.
71 * The oldest idle objects reside on the inactive list, which is in
72 * retirement order. The next objects to retire are those on the (per
73 * ring) active list that do not have an outstanding flush. Once the
74 * hardware reports completion (the seqno is updated after the
75 * batchbuffer has been finished) the clean buffer objects would
76 * be retired to the inactive list. Any dirty objects would be added
77 * to the tail of the flushing list. So after processing the clean
78 * active objects we need to emit a MI_FLUSH to retire the flushing
79 * list, hence the retirement order of the flushing list is in
80 * advance of the dirty objects on the active lists.
81 *
82 * The retirement sequence is thus:
83 * 1. Inactive objects (already retired)
84 * 2. Clean active objects
85 * 3. Flushing list
86 * 4. Dirty active objects.
87 *
88 * On each list, the oldest objects lie at the HEAD with the freshest
89 * object on the TAIL.
90 */
91
92 INIT_LIST_HEAD(&unwind_list);
93 if (mappable)
94 drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space, min_size,
95 alignment, 0,
96 dev_priv->mm.gtt_mappable_end);
97 else
98 drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
99
100 /* First see if there is a large enough contiguous idle region... */
101 list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
102 if (mark_free(obj, &unwind_list))
103 goto found;
104 }
105
106 /* Now merge in the soon-to-be-expired objects... */
107 list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
108 /* Does the object require an outstanding flush? */
109 if (obj->base.write_domain || obj->pin_count)
110 continue;
111
112 if (mark_free(obj, &unwind_list))
113 goto found;
114 }
115
116 /* Finally add anything with a pending flush (in order of retirement) */
117 list_for_each_entry(obj, &dev_priv->mm.flushing_list, mm_list) {
118 if (obj->pin_count)
119 continue;
120
121 if (mark_free(obj, &unwind_list))
122 goto found;
123 }
124 list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
125 if (! obj->base.write_domain || obj->pin_count)
126 continue;
127
128 if (mark_free(obj, &unwind_list))
129 goto found;
130 }
131
132 /* Nothing found, clean up and bail out! */
133 while (!list_empty(&unwind_list)) {
134 obj = list_first_entry(&unwind_list,
135 struct drm_i915_gem_object,
136 exec_list);
137
138 ret = drm_mm_scan_remove_block(obj->gtt_space);
139 BUG_ON(ret);
140
141 list_del_init(&obj->exec_list);
142 drm_gem_object_unreference(&obj->base);
143 }
144
145 /* We expect the caller to unpin, evict all and try again, or give up.
146 * So calling i915_gem_evict_everything() is unnecessary.
147 */
148 return -ENOSPC;
149
150found:
151 /* drm_mm doesn't allow any other other operations while
152 * scanning, therefore store to be evicted objects on a
153 * temporary list. */
154 INIT_LIST_HEAD(&eviction_list);
155 while (!list_empty(&unwind_list)) {
156 obj = list_first_entry(&unwind_list,
157 struct drm_i915_gem_object,
158 exec_list);
159 if (drm_mm_scan_remove_block(obj->gtt_space)) {
160 list_move(&obj->exec_list, &eviction_list);
161 continue;
162 }
163 list_del_init(&obj->exec_list);
164 drm_gem_object_unreference(&obj->base);
165 }
166
167 /* Unbinding will emit any required flushes */
168 while (!list_empty(&eviction_list)) {
169 obj = list_first_entry(&eviction_list,
170 struct drm_i915_gem_object,
171 exec_list);
172 if (ret == 0)
173 ret = i915_gem_object_unbind(obj);
174
175 list_del_init(&obj->exec_list);
176 drm_gem_object_unreference(&obj->base);
177 }
178
179 return ret;
180}
181
182int
183i915_gem_evict_everything(struct drm_device *dev, bool purgeable_only)
184{
185 drm_i915_private_t *dev_priv = dev->dev_private;
186 int ret;
187 bool lists_empty;
188
189 lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
190 list_empty(&dev_priv->mm.flushing_list) &&
191 list_empty(&dev_priv->mm.active_list));
192 if (lists_empty)
193 return -ENOSPC;
194
195 trace_i915_gem_evict_everything(dev, purgeable_only);
196
197 /* Flush everything (on to the inactive lists) and evict */
198 ret = i915_gpu_idle(dev);
199 if (ret)
200 return ret;
201
202 BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
203
204 return i915_gem_evict_inactive(dev, purgeable_only);
205}
206
207/** Unbinds all inactive objects. */
208int
209i915_gem_evict_inactive(struct drm_device *dev, bool purgeable_only)
210{
211 drm_i915_private_t *dev_priv = dev->dev_private;
212 struct drm_i915_gem_object *obj, *next;
213
214 list_for_each_entry_safe(obj, next,
215 &dev_priv->mm.inactive_list, mm_list) {
216 if (!purgeable_only || obj->madv != I915_MADV_WILLNEED) {
217 int ret = i915_gem_object_unbind(obj);
218 if (ret)
219 return ret;
220 }
221 }
222
223 return 0;
224}
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 "gem/i915_gem_context.h"
30#include "gt/intel_gt_requests.h"
31
32#include "i915_drv.h"
33#include "i915_trace.h"
34
35I915_SELFTEST_DECLARE(static struct igt_evict_ctl {
36 bool fail_if_busy:1;
37} igt_evict_ctl;)
38
39static int ggtt_flush(struct intel_gt *gt)
40{
41 /*
42 * Not everything in the GGTT is tracked via vma (otherwise we
43 * could evict as required with minimal stalling) so we are forced
44 * to idle the GPU and explicitly retire outstanding requests in
45 * the hopes that we can then remove contexts and the like only
46 * bound by their active reference.
47 */
48 return intel_gt_wait_for_idle(gt, MAX_SCHEDULE_TIMEOUT);
49}
50
51static bool
52mark_free(struct drm_mm_scan *scan,
53 struct i915_vma *vma,
54 unsigned int flags,
55 struct list_head *unwind)
56{
57 if (i915_vma_is_pinned(vma))
58 return false;
59
60 list_add(&vma->evict_link, unwind);
61 return drm_mm_scan_add_block(scan, &vma->node);
62}
63
64/**
65 * i915_gem_evict_something - Evict vmas to make room for binding a new one
66 * @vm: address space to evict from
67 * @min_size: size of the desired free space
68 * @alignment: alignment constraint of the desired free space
69 * @color: color for the desired space
70 * @start: start (inclusive) of the range from which to evict objects
71 * @end: end (exclusive) of the range from which to evict objects
72 * @flags: additional flags to control the eviction algorithm
73 *
74 * This function will try to evict vmas until a free space satisfying the
75 * requirements is found. Callers must check first whether any such hole exists
76 * already before calling this function.
77 *
78 * This function is used by the object/vma binding code.
79 *
80 * Since this function is only used to free up virtual address space it only
81 * ignores pinned vmas, and not object where the backing storage itself is
82 * pinned. Hence obj->pages_pin_count does not protect against eviction.
83 *
84 * To clarify: This is for freeing up virtual address space, not for freeing
85 * memory in e.g. the shrinker.
86 */
87int
88i915_gem_evict_something(struct i915_address_space *vm,
89 u64 min_size, u64 alignment,
90 unsigned long color,
91 u64 start, u64 end,
92 unsigned flags)
93{
94 struct drm_mm_scan scan;
95 struct list_head eviction_list;
96 struct i915_vma *vma, *next;
97 struct drm_mm_node *node;
98 enum drm_mm_insert_mode mode;
99 struct i915_vma *active;
100 int ret;
101
102 lockdep_assert_held(&vm->mutex);
103 trace_i915_gem_evict(vm, min_size, alignment, flags);
104
105 /*
106 * The goal is to evict objects and amalgamate space in rough LRU order.
107 * Since both active and inactive objects reside on the same list,
108 * in a mix of creation and last scanned order, as we process the list
109 * we sort it into inactive/active, which keeps the active portion
110 * in a rough MRU order.
111 *
112 * The retirement sequence is thus:
113 * 1. Inactive objects (already retired, random order)
114 * 2. Active objects (will stall on unbinding, oldest scanned first)
115 */
116 mode = DRM_MM_INSERT_BEST;
117 if (flags & PIN_HIGH)
118 mode = DRM_MM_INSERT_HIGH;
119 if (flags & PIN_MAPPABLE)
120 mode = DRM_MM_INSERT_LOW;
121 drm_mm_scan_init_with_range(&scan, &vm->mm,
122 min_size, alignment, color,
123 start, end, mode);
124
125 intel_gt_retire_requests(vm->gt);
126
127search_again:
128 active = NULL;
129 INIT_LIST_HEAD(&eviction_list);
130 list_for_each_entry_safe(vma, next, &vm->bound_list, vm_link) {
131 if (vma == active) { /* now seen this vma twice */
132 if (flags & PIN_NONBLOCK)
133 break;
134
135 active = ERR_PTR(-EAGAIN);
136 }
137
138 /*
139 * We keep this list in a rough least-recently scanned order
140 * of active elements (inactive elements are cheap to reap).
141 * New entries are added to the end, and we move anything we
142 * scan to the end. The assumption is that the working set
143 * of applications is either steady state (and thanks to the
144 * userspace bo cache it almost always is) or volatile and
145 * frequently replaced after a frame, which are self-evicting!
146 * Given that assumption, the MRU order of the scan list is
147 * fairly static, and keeping it in least-recently scan order
148 * is suitable.
149 *
150 * To notice when we complete one full cycle, we record the
151 * first active element seen, before moving it to the tail.
152 */
153 if (active != ERR_PTR(-EAGAIN) && i915_vma_is_active(vma)) {
154 if (!active)
155 active = vma;
156
157 list_move_tail(&vma->vm_link, &vm->bound_list);
158 continue;
159 }
160
161 if (mark_free(&scan, vma, flags, &eviction_list))
162 goto found;
163 }
164
165 /* Nothing found, clean up and bail out! */
166 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
167 ret = drm_mm_scan_remove_block(&scan, &vma->node);
168 BUG_ON(ret);
169 }
170
171 /*
172 * Can we unpin some objects such as idle hw contents,
173 * or pending flips? But since only the GGTT has global entries
174 * such as scanouts, rinbuffers and contexts, we can skip the
175 * purge when inspecting per-process local address spaces.
176 */
177 if (!i915_is_ggtt(vm) || flags & PIN_NONBLOCK)
178 return -ENOSPC;
179
180 /*
181 * Not everything in the GGTT is tracked via VMA using
182 * i915_vma_move_to_active(), otherwise we could evict as required
183 * with minimal stalling. Instead we are forced to idle the GPU and
184 * explicitly retire outstanding requests which will then remove
185 * the pinning for active objects such as contexts and ring,
186 * enabling us to evict them on the next iteration.
187 *
188 * To ensure that all user contexts are evictable, we perform
189 * a switch to the perma-pinned kernel context. This all also gives
190 * us a termination condition, when the last retired context is
191 * the kernel's there is no more we can evict.
192 */
193 if (I915_SELFTEST_ONLY(igt_evict_ctl.fail_if_busy))
194 return -EBUSY;
195
196 ret = ggtt_flush(vm->gt);
197 if (ret)
198 return ret;
199
200 cond_resched();
201
202 flags |= PIN_NONBLOCK;
203 goto search_again;
204
205found:
206 /* drm_mm doesn't allow any other other operations while
207 * scanning, therefore store to-be-evicted objects on a
208 * temporary list and take a reference for all before
209 * calling unbind (which may remove the active reference
210 * of any of our objects, thus corrupting the list).
211 */
212 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
213 if (drm_mm_scan_remove_block(&scan, &vma->node))
214 __i915_vma_pin(vma);
215 else
216 list_del(&vma->evict_link);
217 }
218
219 /* Unbinding will emit any required flushes */
220 ret = 0;
221 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
222 __i915_vma_unpin(vma);
223 if (ret == 0)
224 ret = __i915_vma_unbind(vma);
225 }
226
227 while (ret == 0 && (node = drm_mm_scan_color_evict(&scan))) {
228 vma = container_of(node, struct i915_vma, node);
229
230 /* If we find any non-objects (!vma), we cannot evict them */
231 if (vma->node.color != I915_COLOR_UNEVICTABLE)
232 ret = __i915_vma_unbind(vma);
233 else
234 ret = -ENOSPC; /* XXX search failed, try again? */
235 }
236
237 return ret;
238}
239
240/**
241 * i915_gem_evict_for_vma - Evict vmas to make room for binding a new one
242 * @vm: address space to evict from
243 * @target: range (and color) to evict for
244 * @flags: additional flags to control the eviction algorithm
245 *
246 * This function will try to evict vmas that overlap the target node.
247 *
248 * To clarify: This is for freeing up virtual address space, not for freeing
249 * memory in e.g. the shrinker.
250 */
251int i915_gem_evict_for_node(struct i915_address_space *vm,
252 struct drm_mm_node *target,
253 unsigned int flags)
254{
255 LIST_HEAD(eviction_list);
256 struct drm_mm_node *node;
257 u64 start = target->start;
258 u64 end = start + target->size;
259 struct i915_vma *vma, *next;
260 int ret = 0;
261
262 lockdep_assert_held(&vm->mutex);
263 GEM_BUG_ON(!IS_ALIGNED(start, I915_GTT_PAGE_SIZE));
264 GEM_BUG_ON(!IS_ALIGNED(end, I915_GTT_PAGE_SIZE));
265
266 trace_i915_gem_evict_node(vm, target, flags);
267
268 /*
269 * Retire before we search the active list. Although we have
270 * reasonable accuracy in our retirement lists, we may have
271 * a stray pin (preventing eviction) that can only be resolved by
272 * retiring.
273 */
274 intel_gt_retire_requests(vm->gt);
275
276 if (i915_vm_has_cache_coloring(vm)) {
277 /* Expand search to cover neighbouring guard pages (or lack!) */
278 if (start)
279 start -= I915_GTT_PAGE_SIZE;
280
281 /* Always look at the page afterwards to avoid the end-of-GTT */
282 end += I915_GTT_PAGE_SIZE;
283 }
284 GEM_BUG_ON(start >= end);
285
286 drm_mm_for_each_node_in_range(node, &vm->mm, start, end) {
287 /* If we find any non-objects (!vma), we cannot evict them */
288 if (node->color == I915_COLOR_UNEVICTABLE) {
289 ret = -ENOSPC;
290 break;
291 }
292
293 GEM_BUG_ON(!drm_mm_node_allocated(node));
294 vma = container_of(node, typeof(*vma), node);
295
296 /*
297 * If we are using coloring to insert guard pages between
298 * different cache domains within the address space, we have
299 * to check whether the objects on either side of our range
300 * abutt and conflict. If they are in conflict, then we evict
301 * those as well to make room for our guard pages.
302 */
303 if (i915_vm_has_cache_coloring(vm)) {
304 if (node->start + node->size == target->start) {
305 if (node->color == target->color)
306 continue;
307 }
308 if (node->start == target->start + target->size) {
309 if (node->color == target->color)
310 continue;
311 }
312 }
313
314 if (i915_vma_is_pinned(vma)) {
315 ret = -ENOSPC;
316 break;
317 }
318
319 if (flags & PIN_NONBLOCK && i915_vma_is_active(vma)) {
320 ret = -ENOSPC;
321 break;
322 }
323
324 /*
325 * Never show fear in the face of dragons!
326 *
327 * We cannot directly remove this node from within this
328 * iterator and as with i915_gem_evict_something() we employ
329 * the vma pin_count in order to prevent the action of
330 * unbinding one vma from freeing (by dropping its active
331 * reference) another in our eviction list.
332 */
333 __i915_vma_pin(vma);
334 list_add(&vma->evict_link, &eviction_list);
335 }
336
337 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
338 __i915_vma_unpin(vma);
339 if (ret == 0)
340 ret = __i915_vma_unbind(vma);
341 }
342
343 return ret;
344}
345
346/**
347 * i915_gem_evict_vm - Evict all idle vmas from a vm
348 * @vm: Address space to cleanse
349 *
350 * This function evicts all vmas from a vm.
351 *
352 * This is used by the execbuf code as a last-ditch effort to defragment the
353 * address space.
354 *
355 * To clarify: This is for freeing up virtual address space, not for freeing
356 * memory in e.g. the shrinker.
357 */
358int i915_gem_evict_vm(struct i915_address_space *vm)
359{
360 int ret = 0;
361
362 lockdep_assert_held(&vm->mutex);
363 trace_i915_gem_evict_vm(vm);
364
365 /* Switch back to the default context in order to unpin
366 * the existing context objects. However, such objects only
367 * pin themselves inside the global GTT and performing the
368 * switch otherwise is ineffective.
369 */
370 if (i915_is_ggtt(vm)) {
371 ret = ggtt_flush(vm->gt);
372 if (ret)
373 return ret;
374 }
375
376 do {
377 struct i915_vma *vma, *vn;
378 LIST_HEAD(eviction_list);
379
380 list_for_each_entry(vma, &vm->bound_list, vm_link) {
381 if (i915_vma_is_pinned(vma))
382 continue;
383
384 __i915_vma_pin(vma);
385 list_add(&vma->evict_link, &eviction_list);
386 }
387 if (list_empty(&eviction_list))
388 break;
389
390 ret = 0;
391 list_for_each_entry_safe(vma, vn, &eviction_list, evict_link) {
392 __i915_vma_unpin(vma);
393 if (ret == 0)
394 ret = __i915_vma_unbind(vma);
395 if (ret != -EINTR) /* "Get me out of here!" */
396 ret = 0;
397 }
398 } while (ret == 0);
399
400 return ret;
401}
402
403#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
404#include "selftests/i915_gem_evict.c"
405#endif