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