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 mark_free(struct i915_vma *vma, struct list_head *unwind) 38 { 39 if (vma->pin_count) 40 return false; 41 42 if (WARN_ON(!list_empty(&vma->exec_list))) 43 return false; 44 45 list_add(&vma->exec_list, unwind); 46 return drm_mm_scan_add_block(&vma->node); 47 } 48 49 /** 50 * i915_gem_evict_something - Evict vmas to make room for binding a new one 51 * @dev: drm_device 52 * @vm: address space to evict from 53 * @min_size: size of the desired free space 54 * @alignment: alignment constraint of the desired free space 55 * @cache_level: cache_level for the desired space 56 * @start: start (inclusive) of the range from which to evict objects 57 * @end: end (exclusive) of the range from which to evict objects 58 * @flags: additional flags to control the eviction algorithm 59 * 60 * This function will try to evict vmas until a free space satisfying the 61 * requirements is found. Callers must check first whether any such hole exists 62 * already before calling this function. 63 * 64 * This function is used by the object/vma binding code. 65 * 66 * Since this function is only used to free up virtual address space it only 67 * ignores pinned vmas, and not object where the backing storage itself is 68 * pinned. Hence obj->pages_pin_count does not protect against eviction. 69 * 70 * To clarify: This is for freeing up virtual address space, not for freeing 71 * memory in e.g. the shrinker. 72 */ 73 int 74 i915_gem_evict_something(struct drm_device *dev, struct i915_address_space *vm, 75 int min_size, unsigned alignment, unsigned cache_level, 76 unsigned long start, unsigned long end, 77 unsigned flags) 78 { 79 struct list_head eviction_list, unwind_list; 80 struct i915_vma *vma; 81 int ret = 0; 82 int pass = 0; 83 84 trace_i915_gem_evict(dev, min_size, alignment, flags); 85 86 /* 87 * The goal is to evict objects and amalgamate space in LRU order. 88 * The oldest idle objects reside on the inactive list, which is in 89 * retirement order. The next objects to retire are those on the (per 90 * ring) active list that do not have an outstanding flush. Once the 91 * hardware reports completion (the seqno is updated after the 92 * batchbuffer has been finished) the clean buffer objects would 93 * be retired to the inactive list. Any dirty objects would be added 94 * to the tail of the flushing list. So after processing the clean 95 * active objects we need to emit a MI_FLUSH to retire the flushing 96 * list, hence the retirement order of the flushing list is in 97 * advance of the dirty objects on the active lists. 98 * 99 * The retirement sequence is thus: 100 * 1. Inactive objects (already retired) 101 * 2. Clean active objects 102 * 3. Flushing list 103 * 4. Dirty active objects. 104 * 105 * On each list, the oldest objects lie at the HEAD with the freshest 106 * object on the TAIL. 107 */ 108 109 INIT_LIST_HEAD(&unwind_list); 110 if (start != 0 || end != vm->total) { 111 drm_mm_init_scan_with_range(&vm->mm, min_size, 112 alignment, cache_level, 113 start, end); 114 } else 115 drm_mm_init_scan(&vm->mm, min_size, alignment, cache_level); 116 117 search_again: 118 /* First see if there is a large enough contiguous idle region... */ 119 list_for_each_entry(vma, &vm->inactive_list, vm_link) { 120 if (mark_free(vma, &unwind_list)) 121 goto found; 122 } 123 124 if (flags & PIN_NONBLOCK) 125 goto none; 126 127 /* Now merge in the soon-to-be-expired objects... */ 128 list_for_each_entry(vma, &vm->active_list, vm_link) { 129 if (mark_free(vma, &unwind_list)) 130 goto found; 131 } 132 133 none: 134 /* Nothing found, clean up and bail out! */ 135 while (!list_empty(&unwind_list)) { 136 vma = list_first_entry(&unwind_list, 137 struct i915_vma, 138 exec_list); 139 ret = drm_mm_scan_remove_block(&vma->node); 140 BUG_ON(ret); 141 142 list_del_init(&vma->exec_list); 143 } 144 145 /* Can we unpin some objects such as idle hw contents, 146 * or pending flips? 147 */ 148 if (flags & PIN_NONBLOCK) 149 return -ENOSPC; 150 151 /* Only idle the GPU and repeat the search once */ 152 if (pass++ == 0) { 153 ret = i915_gpu_idle(dev); 154 if (ret) 155 return ret; 156 157 i915_gem_retire_requests(dev); 158 goto search_again; 159 } 160 161 /* 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(dev) ? -EAGAIN : -ENOSPC; 166 167 found: 168 /* drm_mm doesn't allow any other other operations while 169 * scanning, therefore store to be evicted objects on a 170 * temporary list. */ 171 INIT_LIST_HEAD(&eviction_list); 172 while (!list_empty(&unwind_list)) { 173 vma = list_first_entry(&unwind_list, 174 struct i915_vma, 175 exec_list); 176 if (drm_mm_scan_remove_block(&vma->node)) { 177 list_move(&vma->exec_list, &eviction_list); 178 drm_gem_object_reference(&vma->obj->base); 179 continue; 180 } 181 list_del_init(&vma->exec_list); 182 } 183 184 /* Unbinding will emit any required flushes */ 185 while (!list_empty(&eviction_list)) { 186 struct drm_gem_object *obj; 187 vma = list_first_entry(&eviction_list, 188 struct i915_vma, 189 exec_list); 190 191 obj = &vma->obj->base; 192 list_del_init(&vma->exec_list); 193 if (ret == 0) 194 ret = i915_vma_unbind(vma); 195 196 drm_gem_object_unreference(obj); 197 } 198 199 return ret; 200 } 201 202 int 203 i915_gem_evict_for_vma(struct i915_vma *target) 204 { 205 struct drm_mm_node *node, *next; 206 207 list_for_each_entry_safe(node, next, 208 &target->vm->mm.head_node.node_list, 209 node_list) { 210 struct i915_vma *vma; 211 int ret; 212 213 if (node->start + node->size <= target->node.start) 214 continue; 215 if (node->start >= target->node.start + target->node.size) 216 break; 217 218 vma = container_of(node, typeof(*vma), node); 219 220 if (vma->pin_count) { 221 if (!vma->exec_entry || (vma->pin_count > 1)) 222 /* Object is pinned for some other use */ 223 return -EBUSY; 224 225 /* We need to evict a buffer in the same batch */ 226 if (vma->exec_entry->flags & EXEC_OBJECT_PINNED) 227 /* Overlapping fixed objects in the same batch */ 228 return -EINVAL; 229 230 return -ENOSPC; 231 } 232 233 ret = i915_vma_unbind(vma); 234 if (ret) 235 return ret; 236 } 237 238 return 0; 239 } 240 241 /** 242 * i915_gem_evict_vm - Evict all idle vmas from a vm 243 * @vm: Address space to cleanse 244 * @do_idle: Boolean directing whether to idle first. 245 * 246 * This function evicts all idles vmas from a vm. If all unpinned vmas should be 247 * evicted the @do_idle needs to be set to true. 248 * 249 * This is used by the execbuf code as a last-ditch effort to defragment the 250 * address space. 251 * 252 * To clarify: This is for freeing up virtual address space, not for freeing 253 * memory in e.g. the shrinker. 254 */ 255 int i915_gem_evict_vm(struct i915_address_space *vm, bool do_idle) 256 { 257 struct i915_vma *vma, *next; 258 int ret; 259 260 WARN_ON(!mutex_is_locked(&vm->dev->struct_mutex)); 261 trace_i915_gem_evict_vm(vm); 262 263 if (do_idle) { 264 ret = i915_gpu_idle(vm->dev); 265 if (ret) 266 return ret; 267 268 i915_gem_retire_requests(vm->dev); 269 270 WARN_ON(!list_empty(&vm->active_list)); 271 } 272 273 list_for_each_entry_safe(vma, next, &vm->inactive_list, vm_link) 274 if (vma->pin_count == 0) 275 WARN_ON(i915_vma_unbind(vma)); 276 277 return 0; 278 } 279