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, struct list_head *unwind)
  36 {
  37         list_add(&obj->exec_list, unwind);
  38         drm_gem_object_reference(&obj->base);
  39         return drm_mm_scan_add_block(obj->gtt_space);
  40 }
  41
  42 int
  43 i915_gem_evict_something(struct drm_device *dev, int min_size,
  44                          unsigned alignment, bool mappable)
  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;
  49         int ret = 0;
  50
  51         i915_gem_retire_requests(dev);
  52
  53         /* Re-check for free space after retiring requests */
  54         if (mappable) {
  55                 if (drm_mm_search_free_in_range(&dev_priv->mm.gtt_space,
  56                                                 min_size, alignment, 0,
  57                                                 dev_priv->mm.gtt_mappable_end,
  58                                                 0))
  59                         return 0;
  60         } else {
  61                 if (drm_mm_search_free(&dev_priv->mm.gtt_space,
  62                                        min_size, alignment, 0))
  63                         return 0;
  64         }
  65
  66         /*
  67          * The goal is to evict objects and amalgamate space in LRU order.
  68          * The oldest idle objects reside on the inactive list, which is in
  69          * retirement order. The next objects to retire are those on the (per
  70          * ring) active list that do not have an outstanding flush. Once the
  71          * hardware reports completion (the seqno is updated after the
  72          * batchbuffer has been finished) the clean buffer objects would
  73          * be retired to the inactive list. Any dirty objects would be added
  74          * to the tail of the flushing list. So after processing the clean
  75          * active objects we need to emit a MI_FLUSH to retire the flushing
  76          * list, hence the retirement order of the flushing list is in
  77          * advance of the dirty objects on the active lists.
  78          *
  79          * The retirement sequence is thus:
  80          *   1. Inactive objects (already retired)
  81          *   2. Clean active objects
  82          *   3. Flushing list
  83          *   4. Dirty active objects.
  84          *
  85          * On each list, the oldest objects lie at the HEAD with the freshest
  86          * object on the TAIL.
  87          */
  88
  89         INIT_LIST_HEAD(&unwind_list);
  90         if (mappable)
  91                 drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space, min_size,
  92                                             alignment, 0,
  93                                             dev_priv->mm.gtt_mappable_end);
  94         else
  95                 drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
  96
  97         /* First see if there is a large enough contiguous idle region... */
  98         list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
  99                 if (mark_free(obj, &unwind_list))
 100                         goto found;
 101         }
 102
 103         /* Now merge in the soon-to-be-expired objects... */
 104         list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
 105                 /* Does the object require an outstanding flush? */
 106                 if (obj->base.write_domain || obj->pin_count)
 107                         continue;
 108
 109                 if (mark_free(obj, &unwind_list))
 110                         goto found;
 111         }
 112
 113         /* Finally add anything with a pending flush (in order of retirement) */
 114         list_for_each_entry(obj, &dev_priv->mm.flushing_list, mm_list) {
 115                 if (obj->pin_count)
 116                         continue;
 117
 118                 if (mark_free(obj, &unwind_list))
 119                         goto found;
 120         }
 121         list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
 122                 if (! obj->base.write_domain || obj->pin_count)
 123                         continue;
 124
 125                 if (mark_free(obj, &unwind_list))
 126                         goto found;
 127         }
 128
 129         /* Nothing found, clean up and bail out! */
 130         while (!list_empty(&unwind_list)) {
 131                 obj = list_first_entry(&unwind_list,
 132                                        struct drm_i915_gem_object,
 133                                        exec_list);
 134
 135                 ret = drm_mm_scan_remove_block(obj->gtt_space);
 136                 BUG_ON(ret);
 137
 138                 list_del_init(&obj->exec_list);
 139                 drm_gem_object_unreference(&obj->base);
 140         }
 141
 142         /* We expect the caller to unpin, evict all and try again, or give up.
 143          * So calling i915_gem_evict_everything() is unnecessary.
 144          */
 145         return -ENOSPC;
 146
 147 found:
 148         /* drm_mm doesn't allow any other other operations while
 149          * scanning, therefore store to be evicted objects on a
 150          * temporary list. */
 151         INIT_LIST_HEAD(&eviction_list);
 152         while (!list_empty(&unwind_list)) {
 153                 obj = list_first_entry(&unwind_list,
 154                                        struct drm_i915_gem_object,
 155                                        exec_list);
 156                 if (drm_mm_scan_remove_block(obj->gtt_space)) {
 157                         list_move(&obj->exec_list, &eviction_list);
 158                         continue;
 159                 }
 160                 list_del_init(&obj->exec_list);
 161                 drm_gem_object_unreference(&obj->base);
 162         }
 163
 164         /* Unbinding will emit any required flushes */
 165         while (!list_empty(&eviction_list)) {
 166                 obj = list_first_entry(&eviction_list,
 167                                        struct drm_i915_gem_object,
 168                                        exec_list);
 169                 if (ret == 0)
 170                         ret = i915_gem_object_unbind(obj);
 171
 172                 list_del_init(&obj->exec_list);
 173                 drm_gem_object_unreference(&obj->base);
 174         }
 175
 176         return ret;
 177 }
 178
 179 int
 180 i915_gem_evict_everything(struct drm_device *dev, bool purgeable_only)
 181 {
 182         drm_i915_private_t *dev_priv = dev->dev_private;
 183         int ret;
 184         bool lists_empty;
 185
 186         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 187                        list_empty(&dev_priv->mm.flushing_list) &&
 188                        list_empty(&dev_priv->mm.active_list));
 189         if (lists_empty)
 190                 return -ENOSPC;
 191
 192         /* Flush everything (on to the inactive lists) and evict */
 193         ret = i915_gpu_idle(dev);
 194         if (ret)
 195                 return ret;
 196
 197         BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
 198
 199         return i915_gem_evict_inactive(dev, purgeable_only);
 200 }
 201
 202 /** Unbinds all inactive objects. */
 203 int
 204 i915_gem_evict_inactive(struct drm_device *dev, bool purgeable_only)
 205 {
 206         drm_i915_private_t *dev_priv = dev->dev_private;
 207         struct drm_i915_gem_object *obj, *next;
 208
 209         list_for_each_entry_safe(obj, next,
 210                                  &dev_priv->mm.inactive_list, mm_list) {
 211                 if (!purgeable_only || obj->madv != I915_MADV_WILLNEED) {
 212                         int ret = i915_gem_object_unbind(obj);
 213                         if (ret)
 214                                 return ret;
 215                 }
 216         }
 217
 218         return 0;
 219 }