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,
  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_priv;
  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         /*
  68          * The goal is to evict objects and amalgamate space in LRU order.
  69          * The oldest idle objects reside on the inactive list, which is in
  70          * retirement order. The next objects to retire are those on the (per
  71          * ring) active list that do not have an outstanding flush. Once the
  72          * hardware reports completion (the seqno is updated after the
  73          * batchbuffer has been finished) the clean buffer objects would
  74          * be retired to the inactive list. Any dirty objects would be added
  75          * to the tail of the flushing list. So after processing the clean
  76          * active objects we need to emit a MI_FLUSH to retire the flushing
  77          * list, hence the retirement order of the flushing list is in
  78          * advance of the dirty objects on the active lists.
  79          *
  80          * The retirement sequence is thus:
  81          *   1. Inactive objects (already retired)
  82          *   2. Clean active objects
  83          *   3. Flushing list
  84          *   4. Dirty active objects.
  85          *
  86          * On each list, the oldest objects lie at the HEAD with the freshest
  87          * object on the TAIL.
  88          */
  89
  90         INIT_LIST_HEAD(&unwind_list);
  91         if (mappable)
  92                 drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space, min_size,
  93                                             alignment, 0,
  94                                             dev_priv->mm.gtt_mappable_end);
  95         else
  96                 drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
  97
  98         /* First see if there is a large enough contiguous idle region... */
  99         list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, mm_list) {
 100                 if (mark_free(obj_priv, &unwind_list))
 101                         goto found;
 102         }
 103
 104         /* Now merge in the soon-to-be-expired objects... */
 105         list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 106                 /* Does the object require an outstanding flush? */
 107                 if (obj_priv->base.write_domain || obj_priv->pin_count)
 108                         continue;
 109
 110                 if (mark_free(obj_priv, &unwind_list))
 111                         goto found;
 112         }
 113
 114         /* Finally add anything with a pending flush (in order of retirement) */
 115         list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, mm_list) {
 116                 if (obj_priv->pin_count)
 117                         continue;
 118
 119                 if (mark_free(obj_priv, &unwind_list))
 120                         goto found;
 121         }
 122         list_for_each_entry(obj_priv, &dev_priv->mm.active_list, mm_list) {
 123                 if (! obj_priv->base.write_domain || obj_priv->pin_count)
 124                         continue;
 125
 126                 if (mark_free(obj_priv, &unwind_list))
 127                         goto found;
 128         }
 129
 130         /* Nothing found, clean up and bail out! */
 131         list_for_each_entry(obj_priv, &unwind_list, evict_list) {
 132                 ret = drm_mm_scan_remove_block(obj_priv->gtt_space);
 133                 BUG_ON(ret);
 134                 drm_gem_object_unreference(&obj_priv->base);
 135         }
 136
 137         /* We expect the caller to unpin, evict all and try again, or give up.
 138          * So calling i915_gem_evict_everything() is unnecessary.
 139          */
 140         return -ENOSPC;
 141
 142 found:
 143         /* drm_mm doesn't allow any other other operations while
 144          * scanning, therefore store to be evicted objects on a
 145          * temporary list. */
 146         INIT_LIST_HEAD(&eviction_list);
 147         while (!list_empty(&unwind_list)) {
 148                 obj_priv = list_first_entry(&unwind_list,
 149                                             struct drm_i915_gem_object,
 150                                             evict_list);
 151                 if (drm_mm_scan_remove_block(obj_priv->gtt_space)) {
 152                         list_move(&obj_priv->evict_list, &eviction_list);
 153                         continue;
 154                 }
 155                 list_del(&obj_priv->evict_list);
 156                 drm_gem_object_unreference(&obj_priv->base);
 157         }
 158
 159         /* Unbinding will emit any required flushes */
 160         while (!list_empty(&eviction_list)) {
 161                 obj_priv = list_first_entry(&eviction_list,
 162                                             struct drm_i915_gem_object,
 163                                             evict_list);
 164                 if (ret == 0)
 165                         ret = i915_gem_object_unbind(&obj_priv->base);
 166                 list_del(&obj_priv->evict_list);
 167                 drm_gem_object_unreference(&obj_priv->base);
 168         }
 169
 170         return ret;
 171 }
 172
 173 int
 174 i915_gem_evict_everything(struct drm_device *dev, bool purgeable_only)
 175 {
 176         drm_i915_private_t *dev_priv = dev->dev_private;
 177         int ret;
 178         bool lists_empty;
 179
 180         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 181                        list_empty(&dev_priv->mm.flushing_list) &&
 182                        list_empty(&dev_priv->mm.active_list));
 183         if (lists_empty)
 184                 return -ENOSPC;
 185
 186         /* Flush everything (on to the inactive lists) and evict */
 187         ret = i915_gpu_idle(dev);
 188         if (ret)
 189                 return ret;
 190
 191         BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
 192
 193         return i915_gem_evict_inactive(dev, purgeable_only);
 194 }
 195
 196 /** Unbinds all inactive objects. */
 197 int
 198 i915_gem_evict_inactive(struct drm_device *dev, bool purgeable_only)
 199 {
 200         drm_i915_private_t *dev_priv = dev->dev_private;
 201         struct drm_i915_gem_object *obj, *next;
 202
 203         list_for_each_entry_safe(obj, next,
 204                                  &dev_priv->mm.inactive_list, mm_list) {
 205                 if (!purgeable_only || obj->madv != I915_MADV_WILLNEED) {
 206                         int ret = i915_gem_object_unbind(&obj->base);
 207                         if (ret)
 208                                 return ret;
 209                 }
 210         }
 211
 212         return 0;
 213 }