sys/dev/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 <drm/drmP.h>
  30 #include <drm/i915_drm.h>
  31 #include "i915_drv.h"
  32
  33 static bool
  34 mark_free(struct drm_i915_gem_object *obj, struct list_head *unwind)
  35 {
  36         if (obj->pin_count)
  37                 return false;
  38
  39         list_add(&obj->exec_list, unwind);
  40         return drm_mm_scan_add_block(obj->gtt_space);
  41 }
  42
  43 int
  44 i915_gem_evict_something(struct drm_device *dev, int min_size,
  45                          unsigned alignment, unsigned cache_level,
  46                          bool mappable, bool nonblocking)
  47 {
  48         drm_i915_private_t *dev_priv = dev->dev_private;
  49         struct list_head eviction_list, unwind_list;
  50         struct drm_i915_gem_object *obj;
  51         int ret = 0;
  52
  53         /*
  54          * The goal is to evict objects and amalgamate space in LRU order.
  55          * The oldest idle objects reside on the inactive list, which is in
  56          * retirement order. The next objects to retire are those on the (per
  57          * ring) active list that do not have an outstanding flush. Once the
  58          * hardware reports completion (the seqno is updated after the
  59          * batchbuffer has been finished) the clean buffer objects would
  60          * be retired to the inactive list. Any dirty objects would be added
  61          * to the tail of the flushing list. So after processing the clean
  62          * active objects we need to emit a MI_FLUSH to retire the flushing
  63          * list, hence the retirement order of the flushing list is in
  64          * advance of the dirty objects on the active lists.
  65          *
  66          * The retirement sequence is thus:
  67          *   1. Inactive objects (already retired)
  68          *   2. Clean active objects
  69          *   3. Flushing list
  70          *   4. Dirty active objects.
  71          *
  72          * On each list, the oldest objects lie at the HEAD with the freshest
  73          * object on the TAIL.
  74          */
  75
  76         INIT_LIST_HEAD(&unwind_list);
  77         if (mappable)
  78                 drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space,
  79                                             min_size, alignment, cache_level,
  80                                             0, dev_priv->mm.gtt_mappable_end);
  81         else
  82                 drm_mm_init_scan(&dev_priv->mm.gtt_space,
  83                                  min_size, alignment, cache_level);
  84
  85         /* First see if there is a large enough contiguous idle region... */
  86         list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
  87                 if (mark_free(obj, &unwind_list))
  88                         goto found;
  89         }
  90
  91         if (nonblocking)
  92                 goto none;
  93
  94         /* Now merge in the soon-to-be-expired objects... */
  95         list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
  96                 if (mark_free(obj, &unwind_list))
  97                         goto found;
  98         }
  99
 100 none:
 101         /* Nothing found, clean up and bail out! */
 102         while (!list_empty(&unwind_list)) {
 103                 obj = list_first_entry(&unwind_list,
 104                                        struct drm_i915_gem_object,
 105                                        exec_list);
 106
 107                 ret = drm_mm_scan_remove_block(obj->gtt_space);
 108                 BUG_ON(ret);
 109
 110                 list_del_init(&obj->exec_list);
 111         }
 112
 113         /* We expect the caller to unpin, evict all and try again, or give up.
 114          * So calling i915_gem_evict_everything() is unnecessary.
 115          */
 116         return -ENOSPC;
 117
 118 found:
 119         /* drm_mm doesn't allow any other other operations while
 120          * scanning, therefore store to be evicted objects on a
 121          * temporary list. */
 122         INIT_LIST_HEAD(&eviction_list);
 123         while (!list_empty(&unwind_list)) {
 124                 obj = list_first_entry(&unwind_list,
 125                                        struct drm_i915_gem_object,
 126                                        exec_list);
 127                 if (drm_mm_scan_remove_block(obj->gtt_space)) {
 128                         list_move(&obj->exec_list, &eviction_list);
 129                         drm_gem_object_reference(&obj->base);
 130                         continue;
 131                 }
 132                 list_del_init(&obj->exec_list);
 133         }
 134
 135         /* Unbinding will emit any required flushes */
 136         while (!list_empty(&eviction_list)) {
 137                 obj = list_first_entry(&eviction_list,
 138                                        struct drm_i915_gem_object,
 139                                        exec_list);
 140                 if (ret == 0)
 141                         ret = i915_gem_object_unbind(obj);
 142
 143                 list_del_init(&obj->exec_list);
 144                 drm_gem_object_unreference(&obj->base);
 145         }
 146
 147         return ret;
 148 }
 149
 150 int
 151 i915_gem_evict_everything(struct drm_device *dev)
 152 {
 153         drm_i915_private_t *dev_priv = dev->dev_private;
 154         struct drm_i915_gem_object *obj, *next;
 155         bool lists_empty;
 156         int ret;
 157
 158         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 159                        list_empty(&dev_priv->mm.active_list));
 160         if (lists_empty)
 161                 return -ENOSPC;
 162
 163         /* The gpu_idle will flush everything in the write domain to the
 164          * active list. Then we must move everything off the active list
 165          * with retire requests.
 166          */
 167         ret = i915_gpu_idle(dev);
 168         if (ret)
 169                 return ret;
 170
 171         i915_gem_retire_requests(dev);
 172
 173         /* Having flushed everything, unbind() should never raise an error */
 174         list_for_each_entry_safe(obj, next,
 175                                  &dev_priv->mm.inactive_list, mm_list)
 176                 if (obj->pin_count == 0)
 177                         WARN_ON(i915_gem_object_unbind(obj));
 178
 179         return 0;
 180 }