2 * Copyright © 2008-2010 Intel Corporation
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:
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
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
24 * Eric Anholt <eric@anholt.net>
25 * Chris Wilson <chris@chris-wilson.co.uuk>
30 #include <drm/i915_drm.h>
33 #include "intel_drv.h"
34 #include "i915_trace.h"
36 static bool ggtt_is_idle(struct drm_i915_private *dev_priv)
38 struct i915_ggtt *ggtt = &dev_priv->ggtt;
39 struct intel_engine_cs *engine;
40 enum intel_engine_id id;
42 for_each_engine(engine, dev_priv, id) {
43 struct intel_timeline *tl;
45 tl = &ggtt->base.timeline.engine[engine->id];
46 if (i915_gem_active_isset(&tl->last_request))
53 static int ggtt_flush(struct drm_i915_private *i915)
57 /* Not everything in the GGTT is tracked via vma (otherwise we
58 * could evict as required with minimal stalling) so we are forced
59 * to idle the GPU and explicitly retire outstanding requests in
60 * the hopes that we can then remove contexts and the like only
61 * bound by their active reference.
63 err = i915_gem_switch_to_kernel_context(i915);
67 err = i915_gem_wait_for_idle(i915,
68 I915_WAIT_INTERRUPTIBLE |
77 mark_free(struct drm_mm_scan *scan,
80 struct list_head *unwind)
82 if (i915_vma_is_pinned(vma))
85 if (flags & PIN_NONFAULT && !list_empty(&vma->obj->userfault_link))
88 list_add(&vma->evict_link, unwind);
89 return drm_mm_scan_add_block(scan, &vma->node);
93 * i915_gem_evict_something - Evict vmas to make room for binding a new one
94 * @vm: address space to evict from
95 * @min_size: size of the desired free space
96 * @alignment: alignment constraint of the desired free space
97 * @cache_level: cache_level for the desired space
98 * @start: start (inclusive) of the range from which to evict objects
99 * @end: end (exclusive) of the range from which to evict objects
100 * @flags: additional flags to control the eviction algorithm
102 * This function will try to evict vmas until a free space satisfying the
103 * requirements is found. Callers must check first whether any such hole exists
104 * already before calling this function.
106 * This function is used by the object/vma binding code.
108 * Since this function is only used to free up virtual address space it only
109 * ignores pinned vmas, and not object where the backing storage itself is
110 * pinned. Hence obj->pages_pin_count does not protect against eviction.
112 * To clarify: This is for freeing up virtual address space, not for freeing
113 * memory in e.g. the shrinker.
116 i915_gem_evict_something(struct i915_address_space *vm,
117 u64 min_size, u64 alignment,
118 unsigned cache_level,
122 struct drm_i915_private *dev_priv = vm->i915;
123 struct drm_mm_scan scan;
124 struct list_head eviction_list;
125 struct list_head *phases[] = {
130 struct i915_vma *vma, *next;
131 struct drm_mm_node *node;
132 enum drm_mm_insert_mode mode;
135 lockdep_assert_held(&vm->i915->drm.struct_mutex);
136 trace_i915_gem_evict(vm, min_size, alignment, flags);
139 * The goal is to evict objects and amalgamate space in LRU order.
140 * The oldest idle objects reside on the inactive list, which is in
141 * retirement order. The next objects to retire are those in flight,
142 * on the active list, again in retirement order.
144 * The retirement sequence is thus:
145 * 1. Inactive objects (already retired)
146 * 2. Active objects (will stall on unbinding)
148 * On each list, the oldest objects lie at the HEAD with the freshest
149 * object on the TAIL.
151 mode = DRM_MM_INSERT_BEST;
152 if (flags & PIN_HIGH)
153 mode = DRM_MM_INSERT_HIGH;
154 if (flags & PIN_MAPPABLE)
155 mode = DRM_MM_INSERT_LOW;
156 drm_mm_scan_init_with_range(&scan, &vm->mm,
157 min_size, alignment, cache_level,
160 /* Retire before we search the active list. Although we have
161 * reasonable accuracy in our retirement lists, we may have
162 * a stray pin (preventing eviction) that can only be resolved by
165 if (!(flags & PIN_NONBLOCK))
166 i915_gem_retire_requests(dev_priv);
171 INIT_LIST_HEAD(&eviction_list);
174 list_for_each_entry(vma, *phase, vm_link)
175 if (mark_free(&scan, vma, flags, &eviction_list))
179 /* Nothing found, clean up and bail out! */
180 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
181 ret = drm_mm_scan_remove_block(&scan, &vma->node);
185 /* Can we unpin some objects such as idle hw contents,
186 * or pending flips? But since only the GGTT has global entries
187 * such as scanouts, rinbuffers and contexts, we can skip the
188 * purge when inspecting per-process local address spaces.
190 if (!i915_is_ggtt(vm) || flags & PIN_NONBLOCK)
193 if (ggtt_is_idle(dev_priv)) {
194 /* If we still have pending pageflip completions, drop
195 * back to userspace to give our workqueues time to
196 * acquire our locks and unpin the old scanouts.
198 return intel_has_pending_fb_unpin(dev_priv) ? -EAGAIN : -ENOSPC;
201 ret = ggtt_flush(dev_priv);
208 /* drm_mm doesn't allow any other other operations while
209 * scanning, therefore store to-be-evicted objects on a
210 * temporary list and take a reference for all before
211 * calling unbind (which may remove the active reference
212 * of any of our objects, thus corrupting the list).
214 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
215 if (drm_mm_scan_remove_block(&scan, &vma->node))
218 list_del(&vma->evict_link);
221 /* Unbinding will emit any required flushes */
223 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
224 __i915_vma_unpin(vma);
226 ret = i915_vma_unbind(vma);
229 while (ret == 0 && (node = drm_mm_scan_color_evict(&scan))) {
230 vma = container_of(node, struct i915_vma, node);
231 ret = i915_vma_unbind(vma);
238 * i915_gem_evict_for_vma - Evict vmas to make room for binding a new one
239 * @vm: address space to evict from
240 * @target: range (and color) to evict for
241 * @flags: additional flags to control the eviction algorithm
243 * This function will try to evict vmas that overlap the target node.
245 * To clarify: This is for freeing up virtual address space, not for freeing
246 * memory in e.g. the shrinker.
248 int i915_gem_evict_for_node(struct i915_address_space *vm,
249 struct drm_mm_node *target,
252 LIST_HEAD(eviction_list);
253 struct drm_mm_node *node;
254 u64 start = target->start;
255 u64 end = start + target->size;
256 struct i915_vma *vma, *next;
260 lockdep_assert_held(&vm->i915->drm.struct_mutex);
261 GEM_BUG_ON(!IS_ALIGNED(start, I915_GTT_PAGE_SIZE));
262 GEM_BUG_ON(!IS_ALIGNED(end, I915_GTT_PAGE_SIZE));
264 trace_i915_gem_evict_node(vm, target, flags);
266 /* Retire before we search the active list. Although we have
267 * reasonable accuracy in our retirement lists, we may have
268 * a stray pin (preventing eviction) that can only be resolved by
271 if (!(flags & PIN_NONBLOCK))
272 i915_gem_retire_requests(vm->i915);
274 check_color = vm->mm.color_adjust;
276 /* Expand search to cover neighbouring guard pages (or lack!) */
278 start -= I915_GTT_PAGE_SIZE;
280 /* Always look at the page afterwards to avoid the end-of-GTT */
281 end += I915_GTT_PAGE_SIZE;
283 GEM_BUG_ON(start >= end);
285 drm_mm_for_each_node_in_range(node, &vm->mm, start, end) {
286 /* If we find any non-objects (!vma), we cannot evict them */
287 if (node->color == I915_COLOR_UNEVICTABLE) {
292 GEM_BUG_ON(!node->allocated);
293 vma = container_of(node, typeof(*vma), node);
295 /* If we are using coloring to insert guard pages between
296 * different cache domains within the address space, we have
297 * to check whether the objects on either side of our range
298 * abutt and conflict. If they are in conflict, then we evict
299 * those as well to make room for our guard pages.
302 if (node->start + node->size == target->start) {
303 if (node->color == target->color)
306 if (node->start == target->start + target->size) {
307 if (node->color == target->color)
312 if (flags & PIN_NONBLOCK &&
313 (i915_vma_is_pinned(vma) || i915_vma_is_active(vma))) {
318 /* Overlap of objects in the same batch? */
319 if (i915_vma_is_pinned(vma)) {
321 if (vma->exec_entry &&
322 vma->exec_entry->flags & EXEC_OBJECT_PINNED)
327 /* Never show fear in the face of dragons!
329 * We cannot directly remove this node from within this
330 * iterator and as with i915_gem_evict_something() we employ
331 * the vma pin_count in order to prevent the action of
332 * unbinding one vma from freeing (by dropping its active
333 * reference) another in our eviction list.
336 list_add(&vma->evict_link, &eviction_list);
339 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
340 __i915_vma_unpin(vma);
342 ret = i915_vma_unbind(vma);
349 * i915_gem_evict_vm - Evict all idle vmas from a vm
350 * @vm: Address space to cleanse
352 * This function evicts all vmas from a vm.
354 * This is used by the execbuf code as a last-ditch effort to defragment the
357 * To clarify: This is for freeing up virtual address space, not for freeing
358 * memory in e.g. the shrinker.
360 int i915_gem_evict_vm(struct i915_address_space *vm)
362 struct list_head *phases[] = {
367 struct list_head eviction_list;
368 struct i915_vma *vma, *next;
371 lockdep_assert_held(&vm->i915->drm.struct_mutex);
372 trace_i915_gem_evict_vm(vm);
374 /* Switch back to the default context in order to unpin
375 * the existing context objects. However, such objects only
376 * pin themselves inside the global GTT and performing the
377 * switch otherwise is ineffective.
379 if (i915_is_ggtt(vm)) {
380 ret = ggtt_flush(vm->i915);
385 INIT_LIST_HEAD(&eviction_list);
388 list_for_each_entry(vma, *phase, vm_link) {
389 if (i915_vma_is_pinned(vma))
393 list_add(&vma->evict_link, &eviction_list);
398 list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
399 __i915_vma_unpin(vma);
401 ret = i915_vma_unbind(vma);
406 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
407 #include "selftests/i915_gem_evict.c"