| 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 | |
| 9 | void i915_gem_ww_ctx_init(struct i915_gem_ww_ctx *ww, bool intr) |
| 10 | { |
| 11 | ww_acquire_init(ctx: &ww->ctx, ww_class: &reservation_ww_class); |
| 12 | INIT_LIST_HEAD(list: &ww->obj_list); |
| 13 | ww->intr = intr; |
| 14 | ww->contended = NULL; |
| 15 | } |
| 16 | |
| 17 | static 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(entry: &obj->obj_link); |
| 23 | i915_gem_object_unlock(obj); |
| 24 | i915_gem_object_put(obj); |
| 25 | } |
| 26 | } |
| 27 | |
| 28 | void i915_gem_ww_unlock_single(struct drm_i915_gem_object *obj) |
| 29 | { |
| 30 | list_del(entry: &obj->obj_link); |
| 31 | i915_gem_object_unlock(obj); |
| 32 | i915_gem_object_put(obj); |
| 33 | } |
| 34 | |
| 35 | void 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(ctx: &ww->ctx); |
| 40 | } |
| 41 | |
| 42 | int __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(obj: ww->contended->base.resv, ctx: &ww->ctx); |
| 52 | else |
| 53 | dma_resv_lock_slow(obj: ww->contended->base.resv, ctx: &ww->ctx); |
| 54 | |
| 55 | if (!ret) |
| 56 | list_add_tail(new: &ww->contended->obj_link, head: &ww->obj_list); |
| 57 | else |
| 58 | i915_gem_object_put(obj: ww->contended); |
| 59 | |
| 60 | ww->contended = NULL; |
| 61 | |
| 62 | return ret; |
| 63 | } |
| 64 |