drivers/gpu/drm/i915/i915_gem_evict.c

   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
  34 static bool
  35 mark_free(struct drm_i915_gem_object *obj_priv,
  36            struct list_head *unwind)
  37 {
  38         list_add(&obj_priv->evict_list, unwind);
  39         drm_gem_object_reference(&obj_priv->base);
  40         return drm_mm_scan_add_block(obj_priv->gtt_space);
  41 }
  42
  43 int
  44 i915_gem_evict_something(struct drm_device *dev, int min_size, unsigned alignment)
  45 {
  46         drm_i915_private_t *dev_priv = dev->dev_private;
  47         struct list_head eviction_list, unwind_list;
  48         struct drm_i915_gem_object *obj_priv;
  49         int ret = 0;
  50
  51         i915_gem_retire_requests(dev);
  52
  53         /* Re-check for free space after retiring requests */
  54         if (drm_mm_search_free(&dev_priv->mm.gtt_space,
  55                                min_size, alignment, 0))
  56                 return 0;
  57
  58         /*
  59          * The goal is to evict objects and amalgamate space in LRU order.
  60          * The oldest idle objects reside on the inactive list, which is in
  61          * retirement order. The next objects to retire are those on the (per
  62          * ring) active list that do not have an outstanding flush. Once the
  63          * hardware reports completion (the seqno is updated after the
  64          * batchbuffer has been finished) the clean buffer objects would
  65          * be retired to the inactive list. Any dirty objects would be added
  66          * to the tail of the flushing list. So after processing the clean
  67          * active objects we need to emit a MI_FLUSH to retire the flushing
  68          * list, hence the retirement order of the flushing list is in
  69          * advance of the dirty objects on the active lists.
  70          *
  71          * The retirement sequence is thus:
  72          *   1. Inactive objects (already retired)
  73          *   2. Clean active objects
  74          *   3. Flushing list
  75          *   4. Dirty active objects.
  76          *
  77          * On each list, the oldest objects lie at the HEAD with the freshest
  78          * object on the TAIL.
  79          */
  80
  81         INIT_LIST_HEAD(&unwind_list);
  82         drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
  83
  84         /* First see if there is a large enough contiguous idle region... */
  85         list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, mm_list) {
  86                 if (mark_free(obj_priv, &unwind_list))
  87                         goto found;
  88         }
  89
  90         /* Now merge in the soon-to-be-expired objects... */
  91         list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
  92                 /* Does the object require an outstanding flush? */
  93                 if (obj_priv->base.write_domain || obj_priv->pin_count)
  94                         continue;
  95
  96                 if (mark_free(obj_priv, &unwind_list))
  97                         goto found;
  98         }
  99
 100         /* Finally add anything with a pending flush (in order of retirement) */
 101         list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, mm_list) {
 102                 if (obj_priv->pin_count)
 103                         continue;
 104
 105                 if (mark_free(obj_priv, &unwind_list))
 106                         goto found;
 107         }
 108         list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 109                 if (! obj_priv->base.write_domain || obj_priv->pin_count)
 110                         continue;
 111
 112                 if (mark_free(obj_priv, &unwind_list))
 113                         goto found;
 114         }
 115
 116         /* Nothing found, clean up and bail out! */
 117         list_for_each_entry(obj_priv, &unwind_list, evict_list) {
 118                 ret = drm_mm_scan_remove_block(obj_priv->gtt_space);
 119                 BUG_ON(ret);
 120                 drm_gem_object_unreference(&obj_priv->base);
 121         }
 122
 123         /* We expect the caller to unpin, evict all and try again, or give up.
 124          * So calling i915_gem_evict_everything() is unnecessary.
 125          */
 126         return -ENOSPC;
 127
 128 found:
 129         /* drm_mm doesn't allow any other other operations while
 130          * scanning, therefore store to be evicted objects on a
 131          * temporary list. */
 132         INIT_LIST_HEAD(&eviction_list);
 133         while (!list_empty(&unwind_list)) {
 134                 obj_priv = list_first_entry(&unwind_list,
 135                                             struct drm_i915_gem_object,
 136                                             evict_list);
 137                 if (drm_mm_scan_remove_block(obj_priv->gtt_space)) {
 138                         list_move(&obj_priv->evict_list, &eviction_list);
 139                         continue;
 140                 }
 141                 list_del(&obj_priv->evict_list);
 142                 drm_gem_object_unreference(&obj_priv->base);
 143         }
 144
 145         /* Unbinding will emit any required flushes */
 146         while (!list_empty(&eviction_list)) {
 147                 obj_priv = list_first_entry(&eviction_list,
 148                                             struct drm_i915_gem_object,
 149                                             evict_list);
 150                 if (ret == 0)
 151                         ret = i915_gem_object_unbind(&obj_priv->base);
 152                 list_del(&obj_priv->evict_list);
 153                 drm_gem_object_unreference(&obj_priv->base);
 154         }
 155
 156         return ret;
 157 }
 158
 159 int
 160 i915_gem_evict_everything(struct drm_device *dev)
 161 {
 162         drm_i915_private_t *dev_priv = dev->dev_private;
 163         int ret;
 164         bool lists_empty;
 165
 166         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 167                        list_empty(&dev_priv->mm.flushing_list) &&
 168                        list_empty(&dev_priv->render_ring.active_list) &&
 169                        list_empty(&dev_priv->bsd_ring.active_list) &&
 170                        list_empty(&dev_priv->blt_ring.active_list));
 171         if (lists_empty)
 172                 return -ENOSPC;
 173
 174         /* Flush everything (on to the inactive lists) and evict */
 175         ret = i915_gpu_idle(dev);
 176         if (ret)
 177                 return ret;
 178
 179         BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
 180
 181         ret = i915_gem_evict_inactive(dev);
 182         if (ret)
 183                 return ret;
 184
 185         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 186                        list_empty(&dev_priv->mm.flushing_list) &&
 187                        list_empty(&dev_priv->render_ring.active_list) &&
 188                        list_empty(&dev_priv->bsd_ring.active_list) &&
 189                        list_empty(&dev_priv->blt_ring.active_list));
 190         BUG_ON(!lists_empty);
 191
 192         return 0;
 193 }
 194
 195 /** Unbinds all inactive objects. */
 196 int
 197 i915_gem_evict_inactive(struct drm_device *dev)
 198 {
 199         drm_i915_private_t *dev_priv = dev->dev_private;
 200
 201         while (!list_empty(&dev_priv->mm.inactive_list)) {
 202                 struct drm_gem_object *obj;
 203                 int ret;
 204
 205                 obj = &list_first_entry(&dev_priv->mm.inactive_list,
 206                                         struct drm_i915_gem_object,
 207                                         mm_list)->base;
 208
 209                 ret = i915_gem_object_unbind(obj);
 210                 if (ret != 0) {
 211                         DRM_ERROR("Error unbinding object: %d\n", ret);
 212                         return ret;
 213                 }
 214         }
 215
 216         return 0;
 217 }