sys/dev/drm2/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 <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <dev/drm2/drmP.h>
  33 #include <dev/drm2/drm.h>
  34 #include <dev/drm2/i915/i915_drm.h>
  35 #include <dev/drm2/i915/i915_drv.h>
  36
  37 static bool
  38 mark_free(struct drm_i915_gem_object *obj, struct list_head *unwind)
  39 {
  40         if (obj->pin_count)
  41                 return false;
  42
  43         list_add(&obj->exec_list, unwind);
  44         return drm_mm_scan_add_block(obj->gtt_space);
  45 }
  46
  47 int
  48 i915_gem_evict_something(struct drm_device *dev, int min_size,
  49                          unsigned alignment, bool mappable)
  50 {
  51         drm_i915_private_t *dev_priv = dev->dev_private;
  52         struct list_head eviction_list, unwind_list;
  53         struct drm_i915_gem_object *obj;
  54         int ret = 0;
  55
  56         CTR4(KTR_DRM, "evict_something %p %d %u %d", dev, min_size,
  57             alignment, mappable);
  58
  59         /*
  60          * The goal is to evict objects and amalgamate space in LRU order.
  61          * The oldest idle objects reside on the inactive list, which is in
  62          * retirement order. The next objects to retire are those on the (per
  63          * ring) active list that do not have an outstanding flush. Once the
  64          * hardware reports completion (the seqno is updated after the
  65          * batchbuffer has been finished) the clean buffer objects would
  66          * be retired to the inactive list. Any dirty objects would be added
  67          * to the tail of the flushing list. So after processing the clean
  68          * active objects we need to emit a MI_FLUSH to retire the flushing
  69          * list, hence the retirement order of the flushing list is in
  70          * advance of the dirty objects on the active lists.
  71          *
  72          * The retirement sequence is thus:
  73          *   1. Inactive objects (already retired)
  74          *   2. Clean active objects
  75          *   3. Flushing list
  76          *   4. Dirty active objects.
  77          *
  78          * On each list, the oldest objects lie at the HEAD with the freshest
  79          * object on the TAIL.
  80          */
  81
  82         INIT_LIST_HEAD(&unwind_list);
  83         if (mappable)
  84                 drm_mm_init_scan_with_range(&dev_priv->mm.gtt_space, min_size,
  85                                             alignment, 0, 0,
  86                                             dev_priv->mm.gtt_mappable_end);
  87         else
  88                 drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment, 0);
  89
  90         /* First see if there is a large enough contiguous idle region... */
  91         list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) {
  92                 if (mark_free(obj, &unwind_list))
  93                         goto found;
  94         }
  95
  96         /* Now merge in the soon-to-be-expired objects... */
  97         list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
  98                 /* Does the object require an outstanding flush? */
  99                 if (obj->base.write_domain)
 100                         continue;
 101
 102                 if (mark_free(obj, &unwind_list))
 103                         goto found;
 104         }
 105
 106         /* Finally add anything with a pending flush (in order of retirement) */
 107         list_for_each_entry(obj, &dev_priv->mm.flushing_list, mm_list) {
 108                 if (mark_free(obj, &unwind_list))
 109                         goto found;
 110         }
 111         list_for_each_entry(obj, &dev_priv->mm.active_list, mm_list) {
 112                 if (!obj->base.write_domain)
 113                         continue;
 114
 115                 if (mark_free(obj, &unwind_list))
 116                         goto found;
 117         }
 118
 119         /* Nothing found, clean up and bail out! */
 120         while (!list_empty(&unwind_list)) {
 121                 obj = list_first_entry(&unwind_list,
 122                                        struct drm_i915_gem_object,
 123                                        exec_list);
 124
 125                 ret = drm_mm_scan_remove_block(obj->gtt_space);
 126                 KASSERT(ret == 0, ("drm_mm_scan_remove_block failed %d", ret));
 127
 128                 list_del_init(&obj->exec_list);
 129         }
 130
 131         /* We expect the caller to unpin, evict all and try again, or give up.
 132          * So calling i915_gem_evict_everything() is unnecessary.
 133          */
 134         return -ENOSPC;
 135
 136 found:
 137         /* drm_mm doesn't allow any other other operations while
 138          * scanning, therefore store to be evicted objects on a
 139          * temporary list. */
 140         INIT_LIST_HEAD(&eviction_list);
 141         while (!list_empty(&unwind_list)) {
 142                 obj = list_first_entry(&unwind_list,
 143                                        struct drm_i915_gem_object,
 144                                        exec_list);
 145                 if (drm_mm_scan_remove_block(obj->gtt_space)) {
 146                         list_move(&obj->exec_list, &eviction_list);
 147                         drm_gem_object_reference(&obj->base);
 148                         continue;
 149                 }
 150                 list_del_init(&obj->exec_list);
 151         }
 152
 153         /* Unbinding will emit any required flushes */
 154         while (!list_empty(&eviction_list)) {
 155                 obj = list_first_entry(&eviction_list,
 156                                        struct drm_i915_gem_object,
 157                                        exec_list);
 158                 if (ret == 0)
 159                         ret = i915_gem_object_unbind(obj);
 160
 161                 list_del_init(&obj->exec_list);
 162                 drm_gem_object_unreference(&obj->base);
 163         }
 164
 165         return ret;
 166 }
 167
 168 int
 169 i915_gem_evict_everything(struct drm_device *dev, bool purgeable_only)
 170 {
 171         drm_i915_private_t *dev_priv = dev->dev_private;
 172         struct drm_i915_gem_object *obj, *next;
 173         bool lists_empty;
 174         int ret;
 175
 176         lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
 177                        list_empty(&dev_priv->mm.flushing_list) &&
 178                        list_empty(&dev_priv->mm.active_list));
 179         if (lists_empty)
 180                 return -ENOSPC;
 181
 182         CTR2(KTR_DRM, "evict_everything %p %d", dev, purgeable_only);
 183
 184         /* The gpu_idle will flush everything in the write domain to the
 185          * active list. Then we must move everything off the active list
 186          * with retire requests.
 187          */
 188         ret = i915_gpu_idle(dev);
 189         if (ret)
 190                 return ret;
 191
 192         i915_gem_retire_requests(dev);
 193
 194         KASSERT(list_empty(&dev_priv->mm.flushing_list),
 195             ("flush list not empty"));
 196
 197         /* Having flushed everything, unbind() should never raise an error */
 198         list_for_each_entry_safe(obj, next,
 199                                  &dev_priv->mm.inactive_list, mm_list) {
 200                 if (!purgeable_only || obj->madv != I915_MADV_WILLNEED) {
 201                         if (obj->pin_count == 0)
 202                                 i915_gem_object_unbind(obj);
 203                 }
 204         }
 205
 206         return 0;
 207 }