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 32 #include "i915_drv.h" 33 #include "intel_drv.h" 34 #include "i915_trace.h" 35 36 static bool ggtt_is_idle(struct drm_i915_private *dev_priv) 37 { 38 struct i915_ggtt *ggtt = &dev_priv->ggtt; 39 struct intel_engine_cs *engine; 40 enum intel_engine_id id; 41 42 for_each_engine(engine, dev_priv, id) { 43 struct intel_timeline *tl; 44 45 tl = &ggtt->base.timeline.engine[engine->id]; 46 if (i915_gem_active_isset(&tl->last_request)) 47 return false; 48 } 49 50 return true; 51 } 52 53 static bool 54 mark_free(struct i915_vma *vma, unsigned int flags, struct list_head *unwind) 55 { 56 if (i915_vma_is_pinned(vma)) 57 return false; 58 59 if (WARN_ON(!list_empty(&vma->exec_list))) 60 return false; 61 62 if (flags & PIN_NONFAULT && !list_empty(&vma->obj->userfault_link)) 63 return false; 64 65 list_add(&vma->exec_list, unwind); 66 return drm_mm_scan_add_block(&vma->node); 67 } 68 69 /** 70 * i915_gem_evict_something - Evict vmas to make room for binding a new one 71 * @vm: address space to evict from 72 * @min_size: size of the desired free space 73 * @alignment: alignment constraint of the desired free space 74 * @cache_level: cache_level for the desired space 75 * @start: start (inclusive) of the range from which to evict objects 76 * @end: end (exclusive) of the range from which to evict objects 77 * @flags: additional flags to control the eviction algorithm 78 * 79 * This function will try to evict vmas until a free space satisfying the 80 * requirements is found. Callers must check first whether any such hole exists 81 * already before calling this function. 82 * 83 * This function is used by the object/vma binding code. 84 * 85 * Since this function is only used to free up virtual address space it only 86 * ignores pinned vmas, and not object where the backing storage itself is 87 * pinned. Hence obj->pages_pin_count does not protect against eviction. 88 * 89 * To clarify: This is for freeing up virtual address space, not for freeing 90 * memory in e.g. the shrinker. 91 */ 92 int 93 i915_gem_evict_something(struct i915_address_space *vm, 94 u64 min_size, u64 alignment, 95 unsigned cache_level, 96 u64 start, u64 end, 97 unsigned flags) 98 { 99 struct drm_i915_private *dev_priv = to_i915(vm->dev); 100 struct list_head eviction_list; 101 struct list_head *phases[] = { 102 &vm->inactive_list, 103 &vm->active_list, 104 NULL, 105 }, **phase; 106 struct i915_vma *vma, *next; 107 int ret; 108 109 lockdep_assert_held(&vm->dev->struct_mutex); 110 trace_i915_gem_evict(vm, min_size, alignment, flags); 111 112 /* 113 * The goal is to evict objects and amalgamate space in LRU order. 114 * The oldest idle objects reside on the inactive list, which is in 115 * retirement order. The next objects to retire are those in flight, 116 * on the active list, again in retirement order. 117 * 118 * The retirement sequence is thus: 119 * 1. Inactive objects (already retired) 120 * 2. Active objects (will stall on unbinding) 121 * 122 * On each list, the oldest objects lie at the HEAD with the freshest 123 * object on the TAIL. 124 */ 125 if (start != 0 || end != vm->total) { 126 drm_mm_init_scan_with_range(&vm->mm, min_size, 127 alignment, cache_level, 128 start, end); 129 } else 130 drm_mm_init_scan(&vm->mm, min_size, alignment, cache_level); 131 132 if (flags & PIN_NONBLOCK) 133 phases[1] = NULL; 134 135 search_again: 136 INIT_LIST_HEAD(&eviction_list); 137 phase = phases; 138 do { 139 list_for_each_entry(vma, *phase, vm_link) 140 if (mark_free(vma, flags, &eviction_list)) 141 goto found; 142 } while (*++phase); 143 144 /* Nothing found, clean up and bail out! */ 145 list_for_each_entry_safe(vma, next, &eviction_list, exec_list) { 146 ret = drm_mm_scan_remove_block(&vma->node); 147 BUG_ON(ret); 148 149 INIT_LIST_HEAD(&vma->exec_list); 150 } 151 152 /* Can we unpin some objects such as idle hw contents, 153 * or pending flips? But since only the GGTT has global entries 154 * such as scanouts, rinbuffers and contexts, we can skip the 155 * purge when inspecting per-process local address spaces. 156 */ 157 if (!i915_is_ggtt(vm) || flags & PIN_NONBLOCK) 158 return -ENOSPC; 159 160 if (ggtt_is_idle(dev_priv)) { 161 /* If we still have pending pageflip completions, drop 162 * back to userspace to give our workqueues time to 163 * acquire our locks and unpin the old scanouts. 164 */ 165 return intel_has_pending_fb_unpin(vm->dev) ? -EAGAIN : -ENOSPC; 166 } 167 168 /* Not everything in the GGTT is tracked via vma (otherwise we 169 * could evict as required with minimal stalling) so we are forced 170 * to idle the GPU and explicitly retire outstanding requests in 171 * the hopes that we can then remove contexts and the like only 172 * bound by their active reference. 173 */ 174 ret = i915_gem_switch_to_kernel_context(dev_priv); 175 if (ret) 176 return ret; 177 178 ret = i915_gem_wait_for_idle(dev_priv, 179 I915_WAIT_INTERRUPTIBLE | 180 I915_WAIT_LOCKED); 181 if (ret) 182 return ret; 183 184 i915_gem_retire_requests(dev_priv); 185 goto search_again; 186 187 found: 188 /* drm_mm doesn't allow any other other operations while 189 * scanning, therefore store to-be-evicted objects on a 190 * temporary list and take a reference for all before 191 * calling unbind (which may remove the active reference 192 * of any of our objects, thus corrupting the list). 193 */ 194 list_for_each_entry_safe(vma, next, &eviction_list, exec_list) { 195 if (drm_mm_scan_remove_block(&vma->node)) 196 __i915_vma_pin(vma); 197 else 198 list_del_init(&vma->exec_list); 199 } 200 201 /* Unbinding will emit any required flushes */ 202 ret = 0; 203 while (!list_empty(&eviction_list)) { 204 vma = list_first_entry(&eviction_list, 205 struct i915_vma, 206 exec_list); 207 208 list_del_init(&vma->exec_list); 209 __i915_vma_unpin(vma); 210 if (ret == 0) 211 ret = i915_vma_unbind(vma); 212 } 213 return ret; 214 } 215 216 int 217 i915_gem_evict_for_vma(struct i915_vma *target) 218 { 219 struct drm_mm_node *node, *next; 220 221 lockdep_assert_held(&target->vm->dev->struct_mutex); 222 223 list_for_each_entry_safe(node, next, 224 &target->vm->mm.head_node.node_list, 225 node_list) { 226 struct i915_vma *vma; 227 int ret; 228 229 if (node->start + node->size <= target->node.start) 230 continue; 231 if (node->start >= target->node.start + target->node.size) 232 break; 233 234 vma = container_of(node, typeof(*vma), node); 235 236 if (i915_vma_is_pinned(vma)) { 237 if (!vma->exec_entry || i915_vma_pin_count(vma) > 1) 238 /* Object is pinned for some other use */ 239 return -EBUSY; 240 241 /* We need to evict a buffer in the same batch */ 242 if (vma->exec_entry->flags & EXEC_OBJECT_PINNED) 243 /* Overlapping fixed objects in the same batch */ 244 return -EINVAL; 245 246 return -ENOSPC; 247 } 248 249 ret = i915_vma_unbind(vma); 250 if (ret) 251 return ret; 252 } 253 254 return 0; 255 } 256 257 /** 258 * i915_gem_evict_vm - Evict all idle vmas from a vm 259 * @vm: Address space to cleanse 260 * @do_idle: Boolean directing whether to idle first. 261 * 262 * This function evicts all idles vmas from a vm. If all unpinned vmas should be 263 * evicted the @do_idle needs to be set to true. 264 * 265 * This is used by the execbuf code as a last-ditch effort to defragment the 266 * address space. 267 * 268 * To clarify: This is for freeing up virtual address space, not for freeing 269 * memory in e.g. the shrinker. 270 */ 271 int i915_gem_evict_vm(struct i915_address_space *vm, bool do_idle) 272 { 273 struct i915_vma *vma, *next; 274 int ret; 275 276 lockdep_assert_held(&vm->dev->struct_mutex); 277 trace_i915_gem_evict_vm(vm); 278 279 if (do_idle) { 280 struct drm_i915_private *dev_priv = to_i915(vm->dev); 281 282 if (i915_is_ggtt(vm)) { 283 ret = i915_gem_switch_to_kernel_context(dev_priv); 284 if (ret) 285 return ret; 286 } 287 288 ret = i915_gem_wait_for_idle(dev_priv, 289 I915_WAIT_INTERRUPTIBLE | 290 I915_WAIT_LOCKED); 291 if (ret) 292 return ret; 293 294 i915_gem_retire_requests(dev_priv); 295 WARN_ON(!list_empty(&vm->active_list)); 296 } 297 298 list_for_each_entry_safe(vma, next, &vm->inactive_list, vm_link) 299 if (!i915_vma_is_pinned(vma)) 300 WARN_ON(i915_vma_unbind(vma)); 301 302 return 0; 303 } 304