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 I915_SELFTEST_DECLARE(static struct igt_evict_ctl
{
40 static bool ggtt_is_idle(struct drm_i915_private
*i915
)
42 struct intel_engine_cs
*engine
;
43 enum intel_engine_id id
;
45 if (i915
->gt
.active_requests
)
48 for_each_engine(engine
, i915
, id
) {
49 if (!intel_engine_has_kernel_context(engine
))
56 static int ggtt_flush(struct drm_i915_private
*i915
)
60 /* Not everything in the GGTT is tracked via vma (otherwise we
61 * could evict as required with minimal stalling) so we are forced
62 * to idle the GPU and explicitly retire outstanding requests in
63 * the hopes that we can then remove contexts and the like only
64 * bound by their active reference.
66 err
= i915_gem_switch_to_kernel_context(i915
);
70 err
= i915_gem_wait_for_idle(i915
,
71 I915_WAIT_INTERRUPTIBLE
|
73 MAX_SCHEDULE_TIMEOUT
);
77 GEM_BUG_ON(!ggtt_is_idle(i915
));
82 mark_free(struct drm_mm_scan
*scan
,
85 struct list_head
*unwind
)
87 if (i915_vma_is_pinned(vma
))
90 if (flags
& PIN_NONFAULT
&& i915_vma_has_userfault(vma
))
93 list_add(&vma
->evict_link
, unwind
);
94 return drm_mm_scan_add_block(scan
, &vma
->node
);
98 * i915_gem_evict_something - Evict vmas to make room for binding a new one
99 * @vm: address space to evict from
100 * @min_size: size of the desired free space
101 * @alignment: alignment constraint of the desired free space
102 * @cache_level: cache_level for the desired space
103 * @start: start (inclusive) of the range from which to evict objects
104 * @end: end (exclusive) of the range from which to evict objects
105 * @flags: additional flags to control the eviction algorithm
107 * This function will try to evict vmas until a free space satisfying the
108 * requirements is found. Callers must check first whether any such hole exists
109 * already before calling this function.
111 * This function is used by the object/vma binding code.
113 * Since this function is only used to free up virtual address space it only
114 * ignores pinned vmas, and not object where the backing storage itself is
115 * pinned. Hence obj->pages_pin_count does not protect against eviction.
117 * To clarify: This is for freeing up virtual address space, not for freeing
118 * memory in e.g. the shrinker.
121 i915_gem_evict_something(struct i915_address_space
*vm
,
122 u64 min_size
, u64 alignment
,
123 unsigned cache_level
,
127 struct drm_i915_private
*dev_priv
= vm
->i915
;
128 struct drm_mm_scan scan
;
129 struct list_head eviction_list
;
130 struct list_head
*phases
[] = {
135 struct i915_vma
*vma
, *next
;
136 struct drm_mm_node
*node
;
137 enum drm_mm_insert_mode mode
;
140 lockdep_assert_held(&vm
->i915
->drm
.struct_mutex
);
141 trace_i915_gem_evict(vm
, min_size
, alignment
, flags
);
144 * The goal is to evict objects and amalgamate space in LRU order.
145 * The oldest idle objects reside on the inactive list, which is in
146 * retirement order. The next objects to retire are those in flight,
147 * on the active list, again in retirement order.
149 * The retirement sequence is thus:
150 * 1. Inactive objects (already retired)
151 * 2. Active objects (will stall on unbinding)
153 * On each list, the oldest objects lie at the HEAD with the freshest
154 * object on the TAIL.
156 mode
= DRM_MM_INSERT_BEST
;
157 if (flags
& PIN_HIGH
)
158 mode
= DRM_MM_INSERT_HIGH
;
159 if (flags
& PIN_MAPPABLE
)
160 mode
= DRM_MM_INSERT_LOW
;
161 drm_mm_scan_init_with_range(&scan
, &vm
->mm
,
162 min_size
, alignment
, cache_level
,
166 * Retire before we search the active list. Although we have
167 * reasonable accuracy in our retirement lists, we may have
168 * a stray pin (preventing eviction) that can only be resolved by
171 if (!(flags
& PIN_NONBLOCK
))
172 i915_retire_requests(dev_priv
);
177 INIT_LIST_HEAD(&eviction_list
);
180 list_for_each_entry(vma
, *phase
, vm_link
)
181 if (mark_free(&scan
, vma
, flags
, &eviction_list
))
185 /* Nothing found, clean up and bail out! */
186 list_for_each_entry_safe(vma
, next
, &eviction_list
, evict_link
) {
187 ret
= drm_mm_scan_remove_block(&scan
, &vma
->node
);
192 * Can we unpin some objects such as idle hw contents,
193 * or pending flips? But since only the GGTT has global entries
194 * such as scanouts, rinbuffers and contexts, we can skip the
195 * purge when inspecting per-process local address spaces.
197 if (!i915_is_ggtt(vm
) || flags
& PIN_NONBLOCK
)
201 * Not everything in the GGTT is tracked via VMA using
202 * i915_vma_move_to_active(), otherwise we could evict as required
203 * with minimal stalling. Instead we are forced to idle the GPU and
204 * explicitly retire outstanding requests which will then remove
205 * the pinning for active objects such as contexts and ring,
206 * enabling us to evict them on the next iteration.
208 * To ensure that all user contexts are evictable, we perform
209 * a switch to the perma-pinned kernel context. This all also gives
210 * us a termination condition, when the last retired context is
211 * the kernel's there is no more we can evict.
213 if (!ggtt_is_idle(dev_priv
)) {
214 if (I915_SELFTEST_ONLY(igt_evict_ctl
.fail_if_busy
))
217 ret
= ggtt_flush(dev_priv
);
226 * If we still have pending pageflip completions, drop
227 * back to userspace to give our workqueues time to
228 * acquire our locks and unpin the old scanouts.
230 return intel_has_pending_fb_unpin(dev_priv
) ? -EAGAIN
: -ENOSPC
;
233 /* drm_mm doesn't allow any other other operations while
234 * scanning, therefore store to-be-evicted objects on a
235 * temporary list and take a reference for all before
236 * calling unbind (which may remove the active reference
237 * of any of our objects, thus corrupting the list).
239 list_for_each_entry_safe(vma
, next
, &eviction_list
, evict_link
) {
240 if (drm_mm_scan_remove_block(&scan
, &vma
->node
))
243 list_del(&vma
->evict_link
);
246 /* Unbinding will emit any required flushes */
248 list_for_each_entry_safe(vma
, next
, &eviction_list
, evict_link
) {
249 __i915_vma_unpin(vma
);
251 ret
= i915_vma_unbind(vma
);
254 while (ret
== 0 && (node
= drm_mm_scan_color_evict(&scan
))) {
255 vma
= container_of(node
, struct i915_vma
, node
);
256 ret
= i915_vma_unbind(vma
);
263 * i915_gem_evict_for_vma - Evict vmas to make room for binding a new one
264 * @vm: address space to evict from
265 * @target: range (and color) to evict for
266 * @flags: additional flags to control the eviction algorithm
268 * This function will try to evict vmas that overlap the target node.
270 * To clarify: This is for freeing up virtual address space, not for freeing
271 * memory in e.g. the shrinker.
273 int i915_gem_evict_for_node(struct i915_address_space
*vm
,
274 struct drm_mm_node
*target
,
277 LIST_HEAD(eviction_list
);
278 struct drm_mm_node
*node
;
279 u64 start
= target
->start
;
280 u64 end
= start
+ target
->size
;
281 struct i915_vma
*vma
, *next
;
285 lockdep_assert_held(&vm
->i915
->drm
.struct_mutex
);
286 GEM_BUG_ON(!IS_ALIGNED(start
, I915_GTT_PAGE_SIZE
));
287 GEM_BUG_ON(!IS_ALIGNED(end
, I915_GTT_PAGE_SIZE
));
289 trace_i915_gem_evict_node(vm
, target
, flags
);
291 /* Retire before we search the active list. Although we have
292 * reasonable accuracy in our retirement lists, we may have
293 * a stray pin (preventing eviction) that can only be resolved by
296 if (!(flags
& PIN_NONBLOCK
))
297 i915_retire_requests(vm
->i915
);
299 check_color
= vm
->mm
.color_adjust
;
301 /* Expand search to cover neighbouring guard pages (or lack!) */
303 start
-= I915_GTT_PAGE_SIZE
;
305 /* Always look at the page afterwards to avoid the end-of-GTT */
306 end
+= I915_GTT_PAGE_SIZE
;
308 GEM_BUG_ON(start
>= end
);
310 drm_mm_for_each_node_in_range(node
, &vm
->mm
, start
, end
) {
311 /* If we find any non-objects (!vma), we cannot evict them */
312 if (node
->color
== I915_COLOR_UNEVICTABLE
) {
317 GEM_BUG_ON(!node
->allocated
);
318 vma
= container_of(node
, typeof(*vma
), node
);
320 /* If we are using coloring to insert guard pages between
321 * different cache domains within the address space, we have
322 * to check whether the objects on either side of our range
323 * abutt and conflict. If they are in conflict, then we evict
324 * those as well to make room for our guard pages.
327 if (node
->start
+ node
->size
== target
->start
) {
328 if (node
->color
== target
->color
)
331 if (node
->start
== target
->start
+ target
->size
) {
332 if (node
->color
== target
->color
)
337 if (flags
& PIN_NONBLOCK
&&
338 (i915_vma_is_pinned(vma
) || i915_vma_is_active(vma
))) {
343 if (flags
& PIN_NONFAULT
&& i915_vma_has_userfault(vma
)) {
348 /* Overlap of objects in the same batch? */
349 if (i915_vma_is_pinned(vma
)) {
351 if (vma
->exec_flags
&&
352 *vma
->exec_flags
& EXEC_OBJECT_PINNED
)
357 /* Never show fear in the face of dragons!
359 * We cannot directly remove this node from within this
360 * iterator and as with i915_gem_evict_something() we employ
361 * the vma pin_count in order to prevent the action of
362 * unbinding one vma from freeing (by dropping its active
363 * reference) another in our eviction list.
366 list_add(&vma
->evict_link
, &eviction_list
);
369 list_for_each_entry_safe(vma
, next
, &eviction_list
, evict_link
) {
370 __i915_vma_unpin(vma
);
372 ret
= i915_vma_unbind(vma
);
379 * i915_gem_evict_vm - Evict all idle vmas from a vm
380 * @vm: Address space to cleanse
382 * This function evicts all vmas from a vm.
384 * This is used by the execbuf code as a last-ditch effort to defragment the
387 * To clarify: This is for freeing up virtual address space, not for freeing
388 * memory in e.g. the shrinker.
390 int i915_gem_evict_vm(struct i915_address_space
*vm
)
392 struct list_head
*phases
[] = {
397 struct list_head eviction_list
;
398 struct i915_vma
*vma
, *next
;
401 lockdep_assert_held(&vm
->i915
->drm
.struct_mutex
);
402 trace_i915_gem_evict_vm(vm
);
404 /* Switch back to the default context in order to unpin
405 * the existing context objects. However, such objects only
406 * pin themselves inside the global GTT and performing the
407 * switch otherwise is ineffective.
409 if (i915_is_ggtt(vm
)) {
410 ret
= ggtt_flush(vm
->i915
);
415 INIT_LIST_HEAD(&eviction_list
);
418 list_for_each_entry(vma
, *phase
, vm_link
) {
419 if (i915_vma_is_pinned(vma
))
423 list_add(&vma
->evict_link
, &eviction_list
);
428 list_for_each_entry_safe(vma
, next
, &eviction_list
, evict_link
) {
429 __i915_vma_unpin(vma
);
431 ret
= i915_vma_unbind(vma
);
436 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
437 #include "selftests/i915_gem_evict.c"