![Chris Wilson](/assets/img/avatar_default.png)
The only time we need to emit a flush inside request emission is after an execbuffer, for which we can use the full __i915_add_request(). All other instances want the simpler i915_add_request() without flushing, so remove the useless helper. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170317114709.8388-1-chris@chris-wilson.co.uk
734 lines
25 KiB
C
734 lines
25 KiB
C
/*
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* Copyright © 2008-2015 Intel Corporation
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice (including the next
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* paragraph) shall be included in all copies or substantial portions of the
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* Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*
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*/
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#ifndef I915_GEM_REQUEST_H
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#define I915_GEM_REQUEST_H
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#include <linux/dma-fence.h>
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#include "i915_gem.h"
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#include "i915_sw_fence.h"
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struct drm_file;
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struct drm_i915_gem_object;
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struct drm_i915_gem_request;
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struct intel_wait {
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struct rb_node node;
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struct task_struct *tsk;
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struct drm_i915_gem_request *request;
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u32 seqno;
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};
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struct intel_signal_node {
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struct rb_node node;
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struct intel_wait wait;
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};
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struct i915_dependency {
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struct i915_priotree *signaler;
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struct list_head signal_link;
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struct list_head wait_link;
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struct list_head dfs_link;
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unsigned long flags;
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#define I915_DEPENDENCY_ALLOC BIT(0)
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};
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/* Requests exist in a complex web of interdependencies. Each request
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* has to wait for some other request to complete before it is ready to be run
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* (e.g. we have to wait until the pixels have been rendering into a texture
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* before we can copy from it). We track the readiness of a request in terms
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* of fences, but we also need to keep the dependency tree for the lifetime
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* of the request (beyond the life of an individual fence). We use the tree
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* at various points to reorder the requests whilst keeping the requests
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* in order with respect to their various dependencies.
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*/
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struct i915_priotree {
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struct list_head signalers_list; /* those before us, we depend upon */
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struct list_head waiters_list; /* those after us, they depend upon us */
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struct rb_node node;
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int priority;
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#define I915_PRIORITY_MAX 1024
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#define I915_PRIORITY_MIN (-I915_PRIORITY_MAX)
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};
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/**
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* Request queue structure.
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*
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* The request queue allows us to note sequence numbers that have been emitted
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* and may be associated with active buffers to be retired.
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*
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* By keeping this list, we can avoid having to do questionable sequence
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* number comparisons on buffer last_read|write_seqno. It also allows an
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* emission time to be associated with the request for tracking how far ahead
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* of the GPU the submission is.
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*
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* When modifying this structure be very aware that we perform a lockless
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* RCU lookup of it that may race against reallocation of the struct
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* from the slab freelist. We intentionally do not zero the structure on
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* allocation so that the lookup can use the dangling pointers (and is
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* cogniscent that those pointers may be wrong). Instead, everything that
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* needs to be initialised must be done so explicitly.
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*
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* The requests are reference counted.
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*/
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struct drm_i915_gem_request {
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struct dma_fence fence;
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spinlock_t lock;
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/** On Which ring this request was generated */
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struct drm_i915_private *i915;
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/**
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* Context and ring buffer related to this request
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* Contexts are refcounted, so when this request is associated with a
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* context, we must increment the context's refcount, to guarantee that
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* it persists while any request is linked to it. Requests themselves
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* are also refcounted, so the request will only be freed when the last
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* reference to it is dismissed, and the code in
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* i915_gem_request_free() will then decrement the refcount on the
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* context.
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*/
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struct i915_gem_context *ctx;
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struct intel_engine_cs *engine;
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struct intel_ring *ring;
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struct intel_timeline *timeline;
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struct intel_signal_node signaling;
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/* Fences for the various phases in the request's lifetime.
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*
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* The submit fence is used to await upon all of the request's
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* dependencies. When it is signaled, the request is ready to run.
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* It is used by the driver to then queue the request for execution.
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*/
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struct i915_sw_fence submit;
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wait_queue_t submitq;
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wait_queue_head_t execute;
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/* A list of everyone we wait upon, and everyone who waits upon us.
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* Even though we will not be submitted to the hardware before the
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* submit fence is signaled (it waits for all external events as well
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* as our own requests), the scheduler still needs to know the
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* dependency tree for the lifetime of the request (from execbuf
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* to retirement), i.e. bidirectional dependency information for the
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* request not tied to individual fences.
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*/
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struct i915_priotree priotree;
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struct i915_dependency dep;
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/** GEM sequence number associated with this request on the
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* global execution timeline. It is zero when the request is not
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* on the HW queue (i.e. not on the engine timeline list).
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* Its value is guarded by the timeline spinlock.
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*/
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u32 global_seqno;
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/** Position in the ring of the start of the request */
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u32 head;
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/**
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* Position in the ring of the start of the postfix.
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* This is required to calculate the maximum available ring space
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* without overwriting the postfix.
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*/
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u32 postfix;
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/** Position in the ring of the end of the whole request */
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u32 tail;
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/** Position in the ring of the end of any workarounds after the tail */
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u32 wa_tail;
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/** Preallocate space in the ring for the emitting the request */
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u32 reserved_space;
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/** Batch buffer related to this request if any (used for
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* error state dump only).
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*/
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struct i915_vma *batch;
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struct list_head active_list;
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/** Time at which this request was emitted, in jiffies. */
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unsigned long emitted_jiffies;
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/** engine->request_list entry for this request */
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struct list_head link;
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/** ring->request_list entry for this request */
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struct list_head ring_link;
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struct drm_i915_file_private *file_priv;
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/** file_priv list entry for this request */
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struct list_head client_link;
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};
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extern const struct dma_fence_ops i915_fence_ops;
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static inline bool dma_fence_is_i915(const struct dma_fence *fence)
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{
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return fence->ops == &i915_fence_ops;
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}
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struct drm_i915_gem_request * __must_check
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i915_gem_request_alloc(struct intel_engine_cs *engine,
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struct i915_gem_context *ctx);
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void i915_gem_request_retire_upto(struct drm_i915_gem_request *req);
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static inline struct drm_i915_gem_request *
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to_request(struct dma_fence *fence)
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{
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/* We assume that NULL fence/request are interoperable */
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BUILD_BUG_ON(offsetof(struct drm_i915_gem_request, fence) != 0);
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GEM_BUG_ON(fence && !dma_fence_is_i915(fence));
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return container_of(fence, struct drm_i915_gem_request, fence);
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}
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static inline struct drm_i915_gem_request *
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i915_gem_request_get(struct drm_i915_gem_request *req)
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{
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return to_request(dma_fence_get(&req->fence));
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}
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static inline struct drm_i915_gem_request *
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i915_gem_request_get_rcu(struct drm_i915_gem_request *req)
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{
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return to_request(dma_fence_get_rcu(&req->fence));
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}
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static inline void
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i915_gem_request_put(struct drm_i915_gem_request *req)
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{
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dma_fence_put(&req->fence);
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}
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static inline void i915_gem_request_assign(struct drm_i915_gem_request **pdst,
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struct drm_i915_gem_request *src)
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{
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if (src)
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i915_gem_request_get(src);
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if (*pdst)
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i915_gem_request_put(*pdst);
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*pdst = src;
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}
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/**
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* i915_gem_request_global_seqno - report the current global seqno
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* @request - the request
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*
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* A request is assigned a global seqno only when it is on the hardware
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* execution queue. The global seqno can be used to maintain a list of
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* requests on the same engine in retirement order, for example for
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* constructing a priority queue for waiting. Prior to its execution, or
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* if it is subsequently removed in the event of preemption, its global
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* seqno is zero. As both insertion and removal from the execution queue
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* may operate in IRQ context, it is not guarded by the usual struct_mutex
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* BKL. Instead those relying on the global seqno must be prepared for its
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* value to change between reads. Only when the request is complete can
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* the global seqno be stable (due to the memory barriers on submitting
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* the commands to the hardware to write the breadcrumb, if the HWS shows
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* that it has passed the global seqno and the global seqno is unchanged
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* after the read, it is indeed complete).
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*/
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static u32
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i915_gem_request_global_seqno(const struct drm_i915_gem_request *request)
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{
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return READ_ONCE(request->global_seqno);
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}
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int
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i915_gem_request_await_object(struct drm_i915_gem_request *to,
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struct drm_i915_gem_object *obj,
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bool write);
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int i915_gem_request_await_dma_fence(struct drm_i915_gem_request *req,
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struct dma_fence *fence);
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void __i915_add_request(struct drm_i915_gem_request *req, bool flush_caches);
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#define i915_add_request(req) \
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__i915_add_request(req, false)
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void __i915_gem_request_submit(struct drm_i915_gem_request *request);
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void i915_gem_request_submit(struct drm_i915_gem_request *request);
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void __i915_gem_request_unsubmit(struct drm_i915_gem_request *request);
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void i915_gem_request_unsubmit(struct drm_i915_gem_request *request);
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struct intel_rps_client;
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#define NO_WAITBOOST ERR_PTR(-1)
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#define IS_RPS_CLIENT(p) (!IS_ERR(p))
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#define IS_RPS_USER(p) (!IS_ERR_OR_NULL(p))
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long i915_wait_request(struct drm_i915_gem_request *req,
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unsigned int flags,
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long timeout)
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__attribute__((nonnull(1)));
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#define I915_WAIT_INTERRUPTIBLE BIT(0)
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#define I915_WAIT_LOCKED BIT(1) /* struct_mutex held, handle GPU reset */
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#define I915_WAIT_ALL BIT(2) /* used by i915_gem_object_wait() */
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static inline u32 intel_engine_get_seqno(struct intel_engine_cs *engine);
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/**
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* Returns true if seq1 is later than seq2.
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*/
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static inline bool i915_seqno_passed(u32 seq1, u32 seq2)
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{
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return (s32)(seq1 - seq2) >= 0;
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}
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static inline bool
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__i915_gem_request_started(const struct drm_i915_gem_request *req, u32 seqno)
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{
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GEM_BUG_ON(!seqno);
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return i915_seqno_passed(intel_engine_get_seqno(req->engine),
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seqno - 1);
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}
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static inline bool
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i915_gem_request_started(const struct drm_i915_gem_request *req)
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{
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u32 seqno;
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seqno = i915_gem_request_global_seqno(req);
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if (!seqno)
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return false;
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return __i915_gem_request_started(req, seqno);
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}
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static inline bool
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__i915_gem_request_completed(const struct drm_i915_gem_request *req, u32 seqno)
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{
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GEM_BUG_ON(!seqno);
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return i915_seqno_passed(intel_engine_get_seqno(req->engine), seqno) &&
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seqno == i915_gem_request_global_seqno(req);
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}
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static inline bool
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i915_gem_request_completed(const struct drm_i915_gem_request *req)
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{
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u32 seqno;
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seqno = i915_gem_request_global_seqno(req);
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if (!seqno)
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return false;
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return __i915_gem_request_completed(req, seqno);
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}
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bool __i915_spin_request(const struct drm_i915_gem_request *request,
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u32 seqno, int state, unsigned long timeout_us);
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static inline bool i915_spin_request(const struct drm_i915_gem_request *request,
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int state, unsigned long timeout_us)
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{
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u32 seqno;
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seqno = i915_gem_request_global_seqno(request);
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if (!seqno)
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return 0;
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return (__i915_gem_request_started(request, seqno) &&
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__i915_spin_request(request, seqno, state, timeout_us));
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}
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/* We treat requests as fences. This is not be to confused with our
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* "fence registers" but pipeline synchronisation objects ala GL_ARB_sync.
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* We use the fences to synchronize access from the CPU with activity on the
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* GPU, for example, we should not rewrite an object's PTE whilst the GPU
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* is reading them. We also track fences at a higher level to provide
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* implicit synchronisation around GEM objects, e.g. set-domain will wait
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* for outstanding GPU rendering before marking the object ready for CPU
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* access, or a pageflip will wait until the GPU is complete before showing
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* the frame on the scanout.
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*
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* In order to use a fence, the object must track the fence it needs to
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* serialise with. For example, GEM objects want to track both read and
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* write access so that we can perform concurrent read operations between
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* the CPU and GPU engines, as well as waiting for all rendering to
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* complete, or waiting for the last GPU user of a "fence register". The
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* object then embeds a #i915_gem_active to track the most recent (in
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* retirement order) request relevant for the desired mode of access.
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* The #i915_gem_active is updated with i915_gem_active_set() to track the
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* most recent fence request, typically this is done as part of
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* i915_vma_move_to_active().
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*
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* When the #i915_gem_active completes (is retired), it will
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* signal its completion to the owner through a callback as well as mark
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* itself as idle (i915_gem_active.request == NULL). The owner
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* can then perform any action, such as delayed freeing of an active
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* resource including itself.
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*/
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struct i915_gem_active;
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typedef void (*i915_gem_retire_fn)(struct i915_gem_active *,
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struct drm_i915_gem_request *);
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struct i915_gem_active {
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struct drm_i915_gem_request __rcu *request;
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struct list_head link;
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i915_gem_retire_fn retire;
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};
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void i915_gem_retire_noop(struct i915_gem_active *,
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struct drm_i915_gem_request *request);
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/**
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* init_request_active - prepares the activity tracker for use
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* @active - the active tracker
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* @func - a callback when then the tracker is retired (becomes idle),
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* can be NULL
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*
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* init_request_active() prepares the embedded @active struct for use as
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* an activity tracker, that is for tracking the last known active request
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* associated with it. When the last request becomes idle, when it is retired
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* after completion, the optional callback @func is invoked.
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*/
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static inline void
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init_request_active(struct i915_gem_active *active,
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i915_gem_retire_fn retire)
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{
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INIT_LIST_HEAD(&active->link);
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active->retire = retire ?: i915_gem_retire_noop;
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}
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/**
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* i915_gem_active_set - updates the tracker to watch the current request
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* @active - the active tracker
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* @request - the request to watch
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*
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* i915_gem_active_set() watches the given @request for completion. Whilst
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* that @request is busy, the @active reports busy. When that @request is
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* retired, the @active tracker is updated to report idle.
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*/
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static inline void
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i915_gem_active_set(struct i915_gem_active *active,
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struct drm_i915_gem_request *request)
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{
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list_move(&active->link, &request->active_list);
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rcu_assign_pointer(active->request, request);
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}
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/**
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* i915_gem_active_set_retire_fn - updates the retirement callback
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* @active - the active tracker
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* @fn - the routine called when the request is retired
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* @mutex - struct_mutex used to guard retirements
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*
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* i915_gem_active_set_retire_fn() updates the function pointer that
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* is called when the final request associated with the @active tracker
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* is retired.
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*/
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static inline void
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i915_gem_active_set_retire_fn(struct i915_gem_active *active,
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i915_gem_retire_fn fn,
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struct mutex *mutex)
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{
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lockdep_assert_held(mutex);
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active->retire = fn ?: i915_gem_retire_noop;
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}
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static inline struct drm_i915_gem_request *
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__i915_gem_active_peek(const struct i915_gem_active *active)
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{
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/* Inside the error capture (running with the driver in an unknown
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* state), we want to bend the rules slightly (a lot).
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*
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* Work is in progress to make it safer, in the meantime this keeps
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* the known issue from spamming the logs.
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*/
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return rcu_dereference_protected(active->request, 1);
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}
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/**
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* i915_gem_active_raw - return the active request
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* @active - the active tracker
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*
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* i915_gem_active_raw() returns the current request being tracked, or NULL.
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* It does not obtain a reference on the request for the caller, so the caller
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* must hold struct_mutex.
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*/
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static inline struct drm_i915_gem_request *
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i915_gem_active_raw(const struct i915_gem_active *active, struct mutex *mutex)
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{
|
|
return rcu_dereference_protected(active->request,
|
|
lockdep_is_held(mutex));
|
|
}
|
|
|
|
/**
|
|
* i915_gem_active_peek - report the active request being monitored
|
|
* @active - the active tracker
|
|
*
|
|
* i915_gem_active_peek() returns the current request being tracked if
|
|
* still active, or NULL. It does not obtain a reference on the request
|
|
* for the caller, so the caller must hold struct_mutex.
|
|
*/
|
|
static inline struct drm_i915_gem_request *
|
|
i915_gem_active_peek(const struct i915_gem_active *active, struct mutex *mutex)
|
|
{
|
|
struct drm_i915_gem_request *request;
|
|
|
|
request = i915_gem_active_raw(active, mutex);
|
|
if (!request || i915_gem_request_completed(request))
|
|
return NULL;
|
|
|
|
return request;
|
|
}
|
|
|
|
/**
|
|
* i915_gem_active_get - return a reference to the active request
|
|
* @active - the active tracker
|
|
*
|
|
* i915_gem_active_get() returns a reference to the active request, or NULL
|
|
* if the active tracker is idle. The caller must hold struct_mutex.
|
|
*/
|
|
static inline struct drm_i915_gem_request *
|
|
i915_gem_active_get(const struct i915_gem_active *active, struct mutex *mutex)
|
|
{
|
|
return i915_gem_request_get(i915_gem_active_peek(active, mutex));
|
|
}
|
|
|
|
/**
|
|
* __i915_gem_active_get_rcu - return a reference to the active request
|
|
* @active - the active tracker
|
|
*
|
|
* __i915_gem_active_get() returns a reference to the active request, or NULL
|
|
* if the active tracker is idle. The caller must hold the RCU read lock, but
|
|
* the returned pointer is safe to use outside of RCU.
|
|
*/
|
|
static inline struct drm_i915_gem_request *
|
|
__i915_gem_active_get_rcu(const struct i915_gem_active *active)
|
|
{
|
|
/* Performing a lockless retrieval of the active request is super
|
|
* tricky. SLAB_DESTROY_BY_RCU merely guarantees that the backing
|
|
* slab of request objects will not be freed whilst we hold the
|
|
* RCU read lock. It does not guarantee that the request itself
|
|
* will not be freed and then *reused*. Viz,
|
|
*
|
|
* Thread A Thread B
|
|
*
|
|
* req = active.request
|
|
* retire(req) -> free(req);
|
|
* (req is now first on the slab freelist)
|
|
* active.request = NULL
|
|
*
|
|
* req = new submission on a new object
|
|
* ref(req)
|
|
*
|
|
* To prevent the request from being reused whilst the caller
|
|
* uses it, we take a reference like normal. Whilst acquiring
|
|
* the reference we check that it is not in a destroyed state
|
|
* (refcnt == 0). That prevents the request being reallocated
|
|
* whilst the caller holds on to it. To check that the request
|
|
* was not reallocated as we acquired the reference we have to
|
|
* check that our request remains the active request across
|
|
* the lookup, in the same manner as a seqlock. The visibility
|
|
* of the pointer versus the reference counting is controlled
|
|
* by using RCU barriers (rcu_dereference and rcu_assign_pointer).
|
|
*
|
|
* In the middle of all that, we inspect whether the request is
|
|
* complete. Retiring is lazy so the request may be completed long
|
|
* before the active tracker is updated. Querying whether the
|
|
* request is complete is far cheaper (as it involves no locked
|
|
* instructions setting cachelines to exclusive) than acquiring
|
|
* the reference, so we do it first. The RCU read lock ensures the
|
|
* pointer dereference is valid, but does not ensure that the
|
|
* seqno nor HWS is the right one! However, if the request was
|
|
* reallocated, that means the active tracker's request was complete.
|
|
* If the new request is also complete, then both are and we can
|
|
* just report the active tracker is idle. If the new request is
|
|
* incomplete, then we acquire a reference on it and check that
|
|
* it remained the active request.
|
|
*
|
|
* It is then imperative that we do not zero the request on
|
|
* reallocation, so that we can chase the dangling pointers!
|
|
* See i915_gem_request_alloc().
|
|
*/
|
|
do {
|
|
struct drm_i915_gem_request *request;
|
|
|
|
request = rcu_dereference(active->request);
|
|
if (!request || i915_gem_request_completed(request))
|
|
return NULL;
|
|
|
|
/* An especially silly compiler could decide to recompute the
|
|
* result of i915_gem_request_completed, more specifically
|
|
* re-emit the load for request->fence.seqno. A race would catch
|
|
* a later seqno value, which could flip the result from true to
|
|
* false. Which means part of the instructions below might not
|
|
* be executed, while later on instructions are executed. Due to
|
|
* barriers within the refcounting the inconsistency can't reach
|
|
* past the call to i915_gem_request_get_rcu, but not executing
|
|
* that while still executing i915_gem_request_put() creates
|
|
* havoc enough. Prevent this with a compiler barrier.
|
|
*/
|
|
barrier();
|
|
|
|
request = i915_gem_request_get_rcu(request);
|
|
|
|
/* What stops the following rcu_access_pointer() from occurring
|
|
* before the above i915_gem_request_get_rcu()? If we were
|
|
* to read the value before pausing to get the reference to
|
|
* the request, we may not notice a change in the active
|
|
* tracker.
|
|
*
|
|
* The rcu_access_pointer() is a mere compiler barrier, which
|
|
* means both the CPU and compiler are free to perform the
|
|
* memory read without constraint. The compiler only has to
|
|
* ensure that any operations after the rcu_access_pointer()
|
|
* occur afterwards in program order. This means the read may
|
|
* be performed earlier by an out-of-order CPU, or adventurous
|
|
* compiler.
|
|
*
|
|
* The atomic operation at the heart of
|
|
* i915_gem_request_get_rcu(), see dma_fence_get_rcu(), is
|
|
* atomic_inc_not_zero() which is only a full memory barrier
|
|
* when successful. That is, if i915_gem_request_get_rcu()
|
|
* returns the request (and so with the reference counted
|
|
* incremented) then the following read for rcu_access_pointer()
|
|
* must occur after the atomic operation and so confirm
|
|
* that this request is the one currently being tracked.
|
|
*
|
|
* The corresponding write barrier is part of
|
|
* rcu_assign_pointer().
|
|
*/
|
|
if (!request || request == rcu_access_pointer(active->request))
|
|
return rcu_pointer_handoff(request);
|
|
|
|
i915_gem_request_put(request);
|
|
} while (1);
|
|
}
|
|
|
|
/**
|
|
* i915_gem_active_get_unlocked - return a reference to the active request
|
|
* @active - the active tracker
|
|
*
|
|
* i915_gem_active_get_unlocked() returns a reference to the active request,
|
|
* or NULL if the active tracker is idle. The reference is obtained under RCU,
|
|
* so no locking is required by the caller.
|
|
*
|
|
* The reference should be freed with i915_gem_request_put().
|
|
*/
|
|
static inline struct drm_i915_gem_request *
|
|
i915_gem_active_get_unlocked(const struct i915_gem_active *active)
|
|
{
|
|
struct drm_i915_gem_request *request;
|
|
|
|
rcu_read_lock();
|
|
request = __i915_gem_active_get_rcu(active);
|
|
rcu_read_unlock();
|
|
|
|
return request;
|
|
}
|
|
|
|
/**
|
|
* i915_gem_active_isset - report whether the active tracker is assigned
|
|
* @active - the active tracker
|
|
*
|
|
* i915_gem_active_isset() returns true if the active tracker is currently
|
|
* assigned to a request. Due to the lazy retiring, that request may be idle
|
|
* and this may report stale information.
|
|
*/
|
|
static inline bool
|
|
i915_gem_active_isset(const struct i915_gem_active *active)
|
|
{
|
|
return rcu_access_pointer(active->request);
|
|
}
|
|
|
|
/**
|
|
* i915_gem_active_wait - waits until the request is completed
|
|
* @active - the active request on which to wait
|
|
* @flags - how to wait
|
|
* @timeout - how long to wait at most
|
|
* @rps - userspace client to charge for a waitboost
|
|
*
|
|
* i915_gem_active_wait() waits until the request is completed before
|
|
* returning, without requiring any locks to be held. Note that it does not
|
|
* retire any requests before returning.
|
|
*
|
|
* This function relies on RCU in order to acquire the reference to the active
|
|
* request without holding any locks. See __i915_gem_active_get_rcu() for the
|
|
* glory details on how that is managed. Once the reference is acquired, we
|
|
* can then wait upon the request, and afterwards release our reference,
|
|
* free of any locking.
|
|
*
|
|
* This function wraps i915_wait_request(), see it for the full details on
|
|
* the arguments.
|
|
*
|
|
* Returns 0 if successful, or a negative error code.
|
|
*/
|
|
static inline int
|
|
i915_gem_active_wait(const struct i915_gem_active *active, unsigned int flags)
|
|
{
|
|
struct drm_i915_gem_request *request;
|
|
long ret = 0;
|
|
|
|
request = i915_gem_active_get_unlocked(active);
|
|
if (request) {
|
|
ret = i915_wait_request(request, flags, MAX_SCHEDULE_TIMEOUT);
|
|
i915_gem_request_put(request);
|
|
}
|
|
|
|
return ret < 0 ? ret : 0;
|
|
}
|
|
|
|
/**
|
|
* i915_gem_active_retire - waits until the request is retired
|
|
* @active - the active request on which to wait
|
|
*
|
|
* i915_gem_active_retire() waits until the request is completed,
|
|
* and then ensures that at least the retirement handler for this
|
|
* @active tracker is called before returning. If the @active
|
|
* tracker is idle, the function returns immediately.
|
|
*/
|
|
static inline int __must_check
|
|
i915_gem_active_retire(struct i915_gem_active *active,
|
|
struct mutex *mutex)
|
|
{
|
|
struct drm_i915_gem_request *request;
|
|
long ret;
|
|
|
|
request = i915_gem_active_raw(active, mutex);
|
|
if (!request)
|
|
return 0;
|
|
|
|
ret = i915_wait_request(request,
|
|
I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED,
|
|
MAX_SCHEDULE_TIMEOUT);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
list_del_init(&active->link);
|
|
RCU_INIT_POINTER(active->request, NULL);
|
|
|
|
active->retire(active, request);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define for_each_active(mask, idx) \
|
|
for (; mask ? idx = ffs(mask) - 1, 1 : 0; mask &= ~BIT(idx))
|
|
|
|
#endif /* I915_GEM_REQUEST_H */
|