diff options
-rw-r--r-- | drivers/gpu/drm/i915/i915_gem_evict.c | 143 |
1 files changed, 70 insertions, 73 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c index 3437ced76cb6..016be7316676 100644 --- a/drivers/gpu/drm/i915/i915_gem_evict.c +++ b/drivers/gpu/drm/i915/i915_gem_evict.c @@ -34,6 +34,19 @@ #include "i915_trace.h" static bool +gpu_is_idle(struct drm_i915_private *dev_priv) +{ + struct intel_engine_cs *engine; + + for_each_engine(engine, dev_priv) { + if (!list_empty(&engine->request_list)) + return false; + } + + return true; +} + +static bool mark_free(struct i915_vma *vma, struct list_head *unwind) { if (vma->pin_count) @@ -76,37 +89,31 @@ i915_gem_evict_something(struct drm_device *dev, struct i915_address_space *vm, unsigned long start, unsigned long end, unsigned flags) { - struct list_head eviction_list, unwind_list; - struct i915_vma *vma; - int ret = 0; - int pass = 0; + struct drm_i915_private *dev_priv = to_i915(dev); + struct list_head eviction_list; + struct list_head *phases[] = { + &vm->inactive_list, + &vm->active_list, + NULL, + }, **phase; + struct i915_vma *vma, *next; + int ret; trace_i915_gem_evict(dev, min_size, alignment, flags); /* * The goal is to evict objects and amalgamate space in LRU order. * The oldest idle objects reside on the inactive list, which is in - * retirement order. The next objects to retire are those on the (per - * ring) active list that do not have an outstanding flush. Once the - * hardware reports completion (the seqno is updated after the - * batchbuffer has been finished) the clean buffer objects would - * be retired to the inactive list. Any dirty objects would be added - * to the tail of the flushing list. So after processing the clean - * active objects we need to emit a MI_FLUSH to retire the flushing - * list, hence the retirement order of the flushing list is in - * advance of the dirty objects on the active lists. + * retirement order. The next objects to retire are those in flight, + * on the active list, again in retirement order. * * The retirement sequence is thus: * 1. Inactive objects (already retired) - * 2. Clean active objects - * 3. Flushing list - * 4. Dirty active objects. + * 2. Active objects (will stall on unbinding) * * On each list, the oldest objects lie at the HEAD with the freshest * object on the TAIL. */ - - INIT_LIST_HEAD(&unwind_list); if (start != 0 || end != vm->total) { drm_mm_init_scan_with_range(&vm->mm, min_size, alignment, cache_level, @@ -114,79 +121,71 @@ i915_gem_evict_something(struct drm_device *dev, struct i915_address_space *vm, } else drm_mm_init_scan(&vm->mm, min_size, alignment, cache_level); -search_again: - /* First see if there is a large enough contiguous idle region... */ - list_for_each_entry(vma, &vm->inactive_list, vm_link) { - if (mark_free(vma, &unwind_list)) - goto found; - } - if (flags & PIN_NONBLOCK) - goto none; + phases[1] = NULL; - /* Now merge in the soon-to-be-expired objects... */ - list_for_each_entry(vma, &vm->active_list, vm_link) { - if (mark_free(vma, &unwind_list)) - goto found; - } +search_again: + INIT_LIST_HEAD(&eviction_list); + phase = phases; + do { + list_for_each_entry(vma, *phase, vm_link) + if (mark_free(vma, &eviction_list)) + goto found; + } while (*++phase); -none: /* Nothing found, clean up and bail out! */ - while (!list_empty(&unwind_list)) { - vma = list_first_entry(&unwind_list, - struct i915_vma, - exec_list); + list_for_each_entry_safe(vma, next, &eviction_list, exec_list) { ret = drm_mm_scan_remove_block(&vma->node); BUG_ON(ret); - list_del_init(&vma->exec_list); + INIT_LIST_HEAD(&vma->exec_list); } /* Can we unpin some objects such as idle hw contents, - * or pending flips? + * or pending flips? But since only the GGTT has global entries + * such as scanouts, rinbuffers and contexts, we can skip the + * purge when inspecting per-process local address spaces. */ - if (flags & PIN_NONBLOCK) + if (!i915_is_ggtt(vm) || flags & PIN_NONBLOCK) return -ENOSPC; - /* Only idle the GPU and repeat the search once */ - if (pass++ == 0) { - struct drm_i915_private *dev_priv = to_i915(dev); - - if (i915_is_ggtt(vm)) { - ret = i915_gem_switch_to_kernel_context(dev_priv); - if (ret) - return ret; - } - - ret = i915_gem_wait_for_idle(dev_priv); - if (ret) - return ret; - - i915_gem_retire_requests(dev_priv); - goto search_again; + if (gpu_is_idle(dev_priv)) { + /* If we still have pending pageflip completions, drop + * back to userspace to give our workqueues time to + * acquire our locks and unpin the old scanouts. + */ + return intel_has_pending_fb_unpin(dev) ? -EAGAIN : -ENOSPC; } - /* If we still have pending pageflip completions, drop - * back to userspace to give our workqueues time to - * acquire our locks and unpin the old scanouts. + /* Not everything in the GGTT is tracked via vma (otherwise we + * could evict as required with minimal stalling) so we are forced + * to idle the GPU and explicitly retire outstanding requests in + * the hopes that we can then remove contexts and the like only + * bound by their active reference. */ - return intel_has_pending_fb_unpin(dev) ? -EAGAIN : -ENOSPC; + ret = i915_gem_switch_to_kernel_context(dev_priv); + if (ret) + return ret; + + ret = i915_gem_wait_for_idle(dev_priv); + if (ret) + return ret; + + i915_gem_retire_requests(dev_priv); + goto search_again; found: /* drm_mm doesn't allow any other other operations while - * scanning, therefore store to be evicted objects on a - * temporary list. */ - INIT_LIST_HEAD(&eviction_list); - while (!list_empty(&unwind_list)) { - vma = list_first_entry(&unwind_list, - struct i915_vma, - exec_list); - if (drm_mm_scan_remove_block(&vma->node)) { + * scanning, therefore store to-be-evicted objects on a + * temporary list and take a reference for all before + * calling unbind (which may remove the active reference + * of any of our objects, thus corrupting the list). + */ + list_for_each_entry_safe(vma, next, &eviction_list, exec_list) { + if (drm_mm_scan_remove_block(&vma->node)) vma->pin_count++; - list_move(&vma->exec_list, &eviction_list); - continue; - } - list_del_init(&vma->exec_list); + else + list_del_init(&vma->exec_list); } /* Unbinding will emit any required flushes */ @@ -200,7 +199,6 @@ found: if (ret == 0) ret = i915_vma_unbind(vma); } - return ret; } @@ -279,7 +277,6 @@ int i915_gem_evict_vm(struct i915_address_space *vm, bool do_idle) return ret; i915_gem_retire_requests(dev_priv); - WARN_ON(!list_empty(&vm->active_list)); } |