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 i915_vma *vma, struct list_head *unwind)
  36 {
  37         if (vma->obj->pin_count)
  38                 return false;
  39
  40         list_add(&vma->exec_list, unwind);
  41         return drm_mm_scan_add_block(&vma->node);
  42 }
  43
  44 int
  45 i915_gem_evict_something(struct drm_device *dev, struct i915_address_space *vm,
  46                          int min_size, 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 i915_vma *vma;
  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                 BUG_ON(!i915_is_ggtt(vm));
  82                 drm_mm_init_scan_with_range(&vm->mm, min_size,
  83                                             alignment, cache_level, 0,
  84                                             dev_priv->gtt.mappable_end);
  85         } else
  86                 drm_mm_init_scan(&vm->mm, min_size, alignment, cache_level);
  87
  88         /* First see if there is a large enough contiguous idle region... */
  89         list_for_each_entry(vma, &vm->inactive_list, mm_list) {
  90                 if (mark_free(vma, &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(vma, &vm->active_list, mm_list) {
  99                 if (mark_free(vma, &unwind_list))
 100                         goto found;
 101         }
 102
 103 none:
 104         /* Nothing found, clean up and bail out! */
 105         while (!list_empty(&unwind_list)) {
 106                 vma = list_first_entry(&unwind_list,
 107                                        struct i915_vma,
 108                                        exec_list);
 109                 ret = drm_mm_scan_remove_block(&vma->node);
 110                 BUG_ON(ret);
 111
 112                 list_del_init(&vma->exec_list);
 113         }
 114
 115         /* We expect the caller to unpin, evict all and try again, or give up.
 116          * So calling i915_gem_evict_everything() is unnecessary.
 117          */
 118         return -ENOSPC;
 119
 120 found:
 121         /* drm_mm doesn't allow any other other operations while
 122          * scanning, therefore store to be evicted objects on a
 123          * temporary list. */
 124         INIT_LIST_HEAD(&eviction_list);
 125         while (!list_empty(&unwind_list)) {
 126                 vma = list_first_entry(&unwind_list,
 127                                        struct i915_vma,
 128                                        exec_list);
 129                 if (drm_mm_scan_remove_block(&vma->node)) {
 130                         list_move(&vma->exec_list, &eviction_list);
 131                         drm_gem_object_reference(&vma->obj->base);
 132                         continue;
 133                 }
 134                 list_del_init(&vma->exec_list);
 135         }
 136
 137         /* Unbinding will emit any required flushes */
 138         while (!list_empty(&eviction_list)) {
 139                 struct drm_gem_object *obj;
 140                 vma = list_first_entry(&eviction_list,
 141                                        struct i915_vma,
 142                                        exec_list);
 143
 144                 obj =  &vma->obj->base;
 145                 list_del_init(&vma->exec_list);
 146                 if (ret == 0)
 147                         ret = i915_vma_unbind(vma);
 148
 149                 drm_gem_object_unreference(obj);
 150         }
 151
 152         return ret;
 153 }
 154
 155 int
 156 i915_gem_evict_everything(struct drm_device *dev)
 157 {
 158         drm_i915_private_t *dev_priv = dev->dev_private;
 159         struct i915_address_space *vm;
 160         struct i915_vma *vma, *next;
 161         bool lists_empty = true;
 162         int ret;
 163
 164         list_for_each_entry(vm, &dev_priv->vm_list, global_link) {
 165                 lists_empty = (list_empty(&vm->inactive_list) &&
 166                                list_empty(&vm->active_list));
 167                 if (!lists_empty)
 168                         lists_empty = false;
 169         }
 170
 171         if (lists_empty)
 172                 return -ENOSPC;
 173
 174         trace_i915_gem_evict_everything(dev);
 175
 176         /* The gpu_idle will flush everything in the write domain to the
 177          * active list. Then we must move everything off the active list
 178          * with retire requests.
 179          */
 180         ret = i915_gpu_idle(dev);
 181         if (ret)
 182                 return ret;
 183
 184         i915_gem_retire_requests(dev);
 185
 186         /* Having flushed everything, unbind() should never raise an error */
 187         list_for_each_entry(vm, &dev_priv->vm_list, global_link) {
 188                 list_for_each_entry_safe(vma, next, &vm->inactive_list, mm_list)
 189                         if (vma->obj->pin_count == 0)
 190                                 WARN_ON(i915_vma_unbind(vma));
 191         }
 192
 193         return 0;
 194 }