1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2020 Intel Corporation 4 */ 5 #include <linux/dma-resv.h> 6 #include "i915_gem_ww.h" 7 #include "gem/i915_gem_object.h" 8 i915_gem_ww_ctx_init(struct i915_gem_ww_ctx * ww,bool intr)9void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ww, bool intr) 10 { 11 ww_acquire_init(&ww->ctx, &reservation_ww_class); 12 INIT_LIST_HEAD(&ww->obj_list); 13 ww->intr = intr; 14 ww->contended = NULL; 15 } 16 i915_gem_ww_ctx_unlock_all(struct i915_gem_ww_ctx * ww)17static void i915_gem_ww_ctx_unlock_all(struct i915_gem_ww_ctx *ww) 18 { 19 struct drm_i915_gem_object *obj; 20 21 while ((obj = list_first_entry_or_null(&ww->obj_list, struct drm_i915_gem_object, obj_link))) { 22 list_del(&obj->obj_link); 23 i915_gem_object_unlock(obj); 24 i915_gem_object_put(obj); 25 } 26 } 27 i915_gem_ww_unlock_single(struct drm_i915_gem_object * obj)28void i915_gem_ww_unlock_single(struct drm_i915_gem_object *obj) 29 { 30 list_del(&obj->obj_link); 31 i915_gem_object_unlock(obj); 32 i915_gem_object_put(obj); 33 } 34 i915_gem_ww_ctx_fini(struct i915_gem_ww_ctx * ww)35void i915_gem_ww_ctx_fini(struct i915_gem_ww_ctx *ww) 36 { 37 i915_gem_ww_ctx_unlock_all(ww); 38 WARN_ON(ww->contended); 39 ww_acquire_fini(&ww->ctx); 40 } 41 i915_gem_ww_ctx_backoff(struct i915_gem_ww_ctx * ww)42int __must_check i915_gem_ww_ctx_backoff(struct i915_gem_ww_ctx *ww) 43 { 44 int ret = 0; 45 46 if (WARN_ON(!ww->contended)) 47 return -EINVAL; 48 49 i915_gem_ww_ctx_unlock_all(ww); 50 if (ww->intr) 51 ret = dma_resv_lock_slow_interruptible(ww->contended->base.resv, &ww->ctx); 52 else 53 dma_resv_lock_slow(ww->contended->base.resv, &ww->ctx); 54 55 if (!ret) 56 list_add_tail(&ww->contended->obj_link, &ww->obj_list); 57 else 58 i915_gem_object_put(ww->contended); 59 60 ww->contended = NULL; 61 62 return ret; 63 } 64