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 <drm/drmP.h>
  30 #include "i915_drv.h"
  31 #include <drm/i915_drm.h>
  32 #include "i915_trace.h"
  33
  34 static bool
  35 mark_free(struct drm_i915_gem_object *obj, struct list_head *unwind)
  36 {
  37         if (obj->pin_count)
  38                 return false;
  39
  40         list_add(&obj->exec_list, unwind);
  41         return drm_mm_scan_add_block(obj->gtt_space);
  42 }
  43
  44 int
  45 i915_gem_evict_something(struct drm_device *dev, int min_size,
  46                          unsigned alignment, unsigned cache_level,
  47                          bool mappable, bool nonblocking)
  48 {
  49         drm_i915_private_t *dev_priv = dev->dev_private;
  50         struct list_head eviction_list, unwind_list;
  51         struct drm_i915_gem_object *obj;
  52         int ret = 0;
  53
  54         trace_i915_gem_evict(dev, min_size, alignment, mappable);
  55
  56         /*
  57          * The goal is to evict objects and amalgamate space in LRU order.
  58          * The oldest idle objects reside on the inactive list, which is in
  59          * retirement order. The next objects to retire are those on the (per
  60          * ring) active list that do not have an outstanding flush. Once the
  61          * hardware reports completion (the seqno is updated after the
  62          * batchbuffer has been finished) the clean buffer objects would
  63          * be retired to the inactive list. Any dirty objects would be added
  64          * to the tail of the flushing list. So after processing the clean
  65          * active objects we need to emit a MI_FLUSH to retire the flushing
  66          * list, hence the retirement order of the flushing list is in
  67          * advance of the dirty objects on the active lists.
  68          *
  69          * The retirement sequence is thus:
  70          *   1. Inactive objects (already retired)
  71          *   2. Clean active objects
  72          *   3. Flushing list
  73          *   4. Dirty active objects.
  74          *
  75          * On each list, the oldest objects lie at the HEAD with the freshest
  76          * object on the TAIL.
  77          */
  78
  79         INIT_LIST_HEAD(&unwind_list);
  80         if (mappable)
  81                 drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space,
  82                                             min_size, alignment, cache_level,
  83                                             0, dev_priv->gtt.mappable_end);
  84         else
  85                 drm_mm_init_scan(&dev_priv->mm.gtt_space,
  86                                  min_size, alignment, cache_level);
  87
  88         /* First see if there is a large enough contiguous idle region... */
  89         list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
  90                 if (mark_free(obj, &unwind_list))
  91                         goto found;
  92         }
  93
  94         if (nonblocking)
  95                 goto none;
  96
  97         /* Now merge in the soon-to-be-expired objects... */
  98         list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
  99                 if (mark_free(obj, &unwind_list))
 100                         goto found;
 101         }
 102
 103 none:
 104         /* Nothing found, clean up and bail out! */
 105         while (!list_empty(&unwind_list)) {
 106                 obj = list_first_entry(&unwind_list,
 107                                        struct drm_i915_gem_object,
 108                                        exec_list);
 109
 110                 ret = drm_mm_scan_remove_block(obj->gtt_space);
 111                 BUG_ON(ret);
 112
 113                 list_del_init(&obj->exec_list);
 114         }
 115
 116         /* We expect the caller to unpin, evict all and try again, or give up.
 117          * So calling i915_gem_evict_everything() is unnecessary.
 118          */
 119         return -ENOSPC;
 120
 121 found:
 122         /* drm_mm doesn't allow any other other operations while
 123          * scanning, therefore store to be evicted objects on a
 124          * temporary list. */
 125         INIT_LIST_HEAD(&eviction_list);
 126         while (!list_empty(&unwind_list)) {
 127                 obj = list_first_entry(&unwind_list,
 128                                        struct drm_i915_gem_object,
 129                                        exec_list);
 130                 if (drm_mm_scan_remove_block(obj->gtt_space)) {
 131                         list_move(&obj->exec_list, &eviction_list);
 132                         drm_gem_object_reference(&obj->base);
 133                         continue;
 134                 }
 135                 list_del_init(&obj->exec_list);
 136         }
 137
 138         /* Unbinding will emit any required flushes */
 139         while (!list_empty(&eviction_list)) {
 140                 obj = list_first_entry(&eviction_list,
 141                                        struct drm_i915_gem_object,
 142                                        exec_list);
 143                 if (ret == 0)
 144                         ret = i915_gem_object_unbind(obj);
 145
 146                 list_del_init(&obj->exec_list);
 147                 drm_gem_object_unreference(&obj->base);
 148         }
 149
 150         return ret;
 151 }
 152
 153 int
 154 i915_gem_evict_everything(struct drm_device *dev)
 155 {
 156         drm_i915_private_t *dev_priv = dev->dev_private;
 157         struct drm_i915_gem_object *obj, *next;
 158         bool lists_empty;
 159         int ret;
 160
 161         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 162                        list_empty(&dev_priv->mm.active_list));
 163         if (lists_empty)
 164                 return -ENOSPC;
 165
 166         trace_i915_gem_evict_everything(dev);
 167
 168         /* The gpu_idle will flush everything in the write domain to the
 169          * active list. Then we must move everything off the active list
 170          * with retire requests.
 171          */
 172         ret = i915_gpu_idle(dev);
 173         if (ret)
 174                 return ret;
 175
 176         i915_gem_retire_requests(dev);
 177
 178         /* Having flushed everything, unbind() should never raise an error */
 179         list_for_each_entry_safe(obj, next,
 180                                  &dev_priv->mm.inactive_list, mm_list)
 181                 if (obj->pin_count == 0)
 182                         WARN_ON(i915_gem_object_unbind(obj));
 183
 184         return 0;
 185 }