drm/i915: Move GEM object waiting to its own file
Continuing the decluttering of i915_gem.c by moving the object wait decomposition into its own file. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190528092956.14910-11-chris@chris-wilson.co.uk
This commit is contained in:
parent
6951e5893b
commit
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@ -105,6 +105,7 @@ gem-y += \
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gem/i915_gem_stolen.o \
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gem/i915_gem_tiling.o \
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gem/i915_gem_userptr.o \
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gem/i915_gem_wait.o \
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gem/i915_gemfs.o
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i915-y += \
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$(gem-y) \
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@ -441,4 +441,12 @@ static inline void __start_cpu_write(struct drm_i915_gem_object *obj)
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obj->cache_dirty = true;
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}
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int i915_gem_object_wait(struct drm_i915_gem_object *obj,
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unsigned int flags,
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long timeout);
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int i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
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unsigned int flags,
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const struct i915_sched_attr *attr);
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#define I915_PRIORITY_DISPLAY I915_USER_PRIORITY(I915_PRIORITY_MAX)
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#endif
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@ -0,0 +1,277 @@
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/*
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* SPDX-License-Identifier: MIT
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*
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* Copyright © 2016 Intel Corporation
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*/
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#include <linux/dma-fence-array.h>
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#include <linux/jiffies.h>
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#include "gt/intel_engine.h"
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#include "i915_gem_ioctls.h"
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#include "i915_gem_object.h"
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static long
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i915_gem_object_wait_fence(struct dma_fence *fence,
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unsigned int flags,
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long timeout)
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{
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BUILD_BUG_ON(I915_WAIT_INTERRUPTIBLE != 0x1);
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if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags))
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return timeout;
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if (dma_fence_is_i915(fence))
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return i915_request_wait(to_request(fence), flags, timeout);
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return dma_fence_wait_timeout(fence,
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flags & I915_WAIT_INTERRUPTIBLE,
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timeout);
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}
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static long
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i915_gem_object_wait_reservation(struct reservation_object *resv,
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unsigned int flags,
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long timeout)
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{
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unsigned int seq = __read_seqcount_begin(&resv->seq);
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struct dma_fence *excl;
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bool prune_fences = false;
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if (flags & I915_WAIT_ALL) {
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struct dma_fence **shared;
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unsigned int count, i;
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int ret;
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ret = reservation_object_get_fences_rcu(resv,
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&excl, &count, &shared);
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if (ret)
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return ret;
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for (i = 0; i < count; i++) {
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timeout = i915_gem_object_wait_fence(shared[i],
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flags, timeout);
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if (timeout < 0)
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break;
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dma_fence_put(shared[i]);
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}
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for (; i < count; i++)
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dma_fence_put(shared[i]);
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kfree(shared);
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/*
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* If both shared fences and an exclusive fence exist,
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* then by construction the shared fences must be later
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* than the exclusive fence. If we successfully wait for
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* all the shared fences, we know that the exclusive fence
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* must all be signaled. If all the shared fences are
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* signaled, we can prune the array and recover the
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* floating references on the fences/requests.
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*/
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prune_fences = count && timeout >= 0;
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} else {
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excl = reservation_object_get_excl_rcu(resv);
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}
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if (excl && timeout >= 0)
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timeout = i915_gem_object_wait_fence(excl, flags, timeout);
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dma_fence_put(excl);
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/*
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* Opportunistically prune the fences iff we know they have *all* been
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* signaled and that the reservation object has not been changed (i.e.
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* no new fences have been added).
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*/
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if (prune_fences && !__read_seqcount_retry(&resv->seq, seq)) {
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if (reservation_object_trylock(resv)) {
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if (!__read_seqcount_retry(&resv->seq, seq))
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reservation_object_add_excl_fence(resv, NULL);
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reservation_object_unlock(resv);
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}
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}
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return timeout;
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}
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static void __fence_set_priority(struct dma_fence *fence,
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const struct i915_sched_attr *attr)
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{
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struct i915_request *rq;
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struct intel_engine_cs *engine;
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if (dma_fence_is_signaled(fence) || !dma_fence_is_i915(fence))
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return;
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rq = to_request(fence);
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engine = rq->engine;
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local_bh_disable();
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rcu_read_lock(); /* RCU serialisation for set-wedged protection */
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if (engine->schedule)
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engine->schedule(rq, attr);
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rcu_read_unlock();
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local_bh_enable(); /* kick the tasklets if queues were reprioritised */
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}
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static void fence_set_priority(struct dma_fence *fence,
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const struct i915_sched_attr *attr)
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{
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/* Recurse once into a fence-array */
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if (dma_fence_is_array(fence)) {
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struct dma_fence_array *array = to_dma_fence_array(fence);
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int i;
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for (i = 0; i < array->num_fences; i++)
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__fence_set_priority(array->fences[i], attr);
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} else {
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__fence_set_priority(fence, attr);
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}
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}
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int
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i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
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unsigned int flags,
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const struct i915_sched_attr *attr)
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{
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struct dma_fence *excl;
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if (flags & I915_WAIT_ALL) {
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struct dma_fence **shared;
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unsigned int count, i;
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int ret;
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ret = reservation_object_get_fences_rcu(obj->resv,
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&excl, &count, &shared);
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if (ret)
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return ret;
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for (i = 0; i < count; i++) {
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fence_set_priority(shared[i], attr);
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dma_fence_put(shared[i]);
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}
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kfree(shared);
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} else {
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excl = reservation_object_get_excl_rcu(obj->resv);
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}
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if (excl) {
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fence_set_priority(excl, attr);
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dma_fence_put(excl);
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}
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return 0;
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}
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/**
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* Waits for rendering to the object to be completed
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* @obj: i915 gem object
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* @flags: how to wait (under a lock, for all rendering or just for writes etc)
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* @timeout: how long to wait
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*/
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int
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i915_gem_object_wait(struct drm_i915_gem_object *obj,
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unsigned int flags,
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long timeout)
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{
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might_sleep();
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GEM_BUG_ON(timeout < 0);
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timeout = i915_gem_object_wait_reservation(obj->resv, flags, timeout);
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return timeout < 0 ? timeout : 0;
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}
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static inline unsigned long nsecs_to_jiffies_timeout(const u64 n)
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{
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/* nsecs_to_jiffies64() does not guard against overflow */
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if (NSEC_PER_SEC % HZ &&
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div_u64(n, NSEC_PER_SEC) >= MAX_JIFFY_OFFSET / HZ)
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return MAX_JIFFY_OFFSET;
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return min_t(u64, MAX_JIFFY_OFFSET, nsecs_to_jiffies64(n) + 1);
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}
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static unsigned long to_wait_timeout(s64 timeout_ns)
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{
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if (timeout_ns < 0)
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return MAX_SCHEDULE_TIMEOUT;
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if (timeout_ns == 0)
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return 0;
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return nsecs_to_jiffies_timeout(timeout_ns);
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}
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/**
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* i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT
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* @dev: drm device pointer
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* @data: ioctl data blob
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* @file: drm file pointer
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*
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* Returns 0 if successful, else an error is returned with the remaining time in
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* the timeout parameter.
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* -ETIME: object is still busy after timeout
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* -ERESTARTSYS: signal interrupted the wait
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* -ENONENT: object doesn't exist
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* Also possible, but rare:
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* -EAGAIN: incomplete, restart syscall
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* -ENOMEM: damn
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* -ENODEV: Internal IRQ fail
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* -E?: The add request failed
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*
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* The wait ioctl with a timeout of 0 reimplements the busy ioctl. With any
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* non-zero timeout parameter the wait ioctl will wait for the given number of
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* nanoseconds on an object becoming unbusy. Since the wait itself does so
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* without holding struct_mutex the object may become re-busied before this
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* function completes. A similar but shorter * race condition exists in the busy
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* ioctl
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*/
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int
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i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
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{
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struct drm_i915_gem_wait *args = data;
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struct drm_i915_gem_object *obj;
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ktime_t start;
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long ret;
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if (args->flags != 0)
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return -EINVAL;
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obj = i915_gem_object_lookup(file, args->bo_handle);
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if (!obj)
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return -ENOENT;
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start = ktime_get();
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ret = i915_gem_object_wait(obj,
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I915_WAIT_INTERRUPTIBLE |
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I915_WAIT_PRIORITY |
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I915_WAIT_ALL,
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to_wait_timeout(args->timeout_ns));
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if (args->timeout_ns > 0) {
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args->timeout_ns -= ktime_to_ns(ktime_sub(ktime_get(), start));
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if (args->timeout_ns < 0)
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args->timeout_ns = 0;
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/*
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* Apparently ktime isn't accurate enough and occasionally has a
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* bit of mismatch in the jiffies<->nsecs<->ktime loop. So patch
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* things up to make the test happy. We allow up to 1 jiffy.
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*
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* This is a regression from the timespec->ktime conversion.
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*/
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if (ret == -ETIME && !nsecs_to_jiffies(args->timeout_ns))
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args->timeout_ns = 0;
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/* Asked to wait beyond the jiffie/scheduler precision? */
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if (ret == -ETIME && args->timeout_ns)
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ret = -EAGAIN;
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}
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i915_gem_object_put(obj);
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return ret;
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}
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@ -2758,13 +2758,6 @@ void i915_gem_suspend(struct drm_i915_private *dev_priv);
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void i915_gem_suspend_late(struct drm_i915_private *dev_priv);
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void i915_gem_resume(struct drm_i915_private *dev_priv);
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vm_fault_t i915_gem_fault(struct vm_fault *vmf);
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int i915_gem_object_wait(struct drm_i915_gem_object *obj,
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unsigned int flags,
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long timeout);
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int i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
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unsigned int flags,
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const struct i915_sched_attr *attr);
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#define I915_PRIORITY_DISPLAY I915_USER_PRIORITY(I915_PRIORITY_MAX)
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int i915_gem_open(struct drm_i915_private *i915, struct drm_file *file);
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void i915_gem_release(struct drm_device *dev, struct drm_file *file);
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@ -125,178 +125,6 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj)
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return ret;
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}
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static long
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i915_gem_object_wait_fence(struct dma_fence *fence,
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unsigned int flags,
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long timeout)
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{
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BUILD_BUG_ON(I915_WAIT_INTERRUPTIBLE != 0x1);
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if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags))
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return timeout;
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if (dma_fence_is_i915(fence))
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return i915_request_wait(to_request(fence), flags, timeout);
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return dma_fence_wait_timeout(fence,
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flags & I915_WAIT_INTERRUPTIBLE,
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timeout);
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}
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static long
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i915_gem_object_wait_reservation(struct reservation_object *resv,
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unsigned int flags,
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long timeout)
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{
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unsigned int seq = __read_seqcount_begin(&resv->seq);
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struct dma_fence *excl;
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bool prune_fences = false;
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if (flags & I915_WAIT_ALL) {
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struct dma_fence **shared;
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unsigned int count, i;
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int ret;
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ret = reservation_object_get_fences_rcu(resv,
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&excl, &count, &shared);
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if (ret)
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return ret;
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for (i = 0; i < count; i++) {
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timeout = i915_gem_object_wait_fence(shared[i],
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flags, timeout);
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if (timeout < 0)
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break;
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dma_fence_put(shared[i]);
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}
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for (; i < count; i++)
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dma_fence_put(shared[i]);
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kfree(shared);
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/*
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* If both shared fences and an exclusive fence exist,
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* then by construction the shared fences must be later
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* than the exclusive fence. If we successfully wait for
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* all the shared fences, we know that the exclusive fence
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* must all be signaled. If all the shared fences are
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* signaled, we can prune the array and recover the
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* floating references on the fences/requests.
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*/
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prune_fences = count && timeout >= 0;
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} else {
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excl = reservation_object_get_excl_rcu(resv);
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}
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if (excl && timeout >= 0)
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timeout = i915_gem_object_wait_fence(excl, flags, timeout);
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dma_fence_put(excl);
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/*
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* Opportunistically prune the fences iff we know they have *all* been
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* signaled and that the reservation object has not been changed (i.e.
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* no new fences have been added).
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*/
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if (prune_fences && !__read_seqcount_retry(&resv->seq, seq)) {
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if (reservation_object_trylock(resv)) {
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if (!__read_seqcount_retry(&resv->seq, seq))
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reservation_object_add_excl_fence(resv, NULL);
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reservation_object_unlock(resv);
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}
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}
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return timeout;
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}
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static void __fence_set_priority(struct dma_fence *fence,
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const struct i915_sched_attr *attr)
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{
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struct i915_request *rq;
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struct intel_engine_cs *engine;
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if (dma_fence_is_signaled(fence) || !dma_fence_is_i915(fence))
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return;
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rq = to_request(fence);
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engine = rq->engine;
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local_bh_disable();
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rcu_read_lock(); /* RCU serialisation for set-wedged protection */
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if (engine->schedule)
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engine->schedule(rq, attr);
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rcu_read_unlock();
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local_bh_enable(); /* kick the tasklets if queues were reprioritised */
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}
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static void fence_set_priority(struct dma_fence *fence,
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const struct i915_sched_attr *attr)
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{
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/* Recurse once into a fence-array */
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if (dma_fence_is_array(fence)) {
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struct dma_fence_array *array = to_dma_fence_array(fence);
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int i;
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for (i = 0; i < array->num_fences; i++)
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__fence_set_priority(array->fences[i], attr);
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} else {
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__fence_set_priority(fence, attr);
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}
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}
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int
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i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
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unsigned int flags,
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const struct i915_sched_attr *attr)
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{
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struct dma_fence *excl;
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if (flags & I915_WAIT_ALL) {
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struct dma_fence **shared;
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unsigned int count, i;
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int ret;
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ret = reservation_object_get_fences_rcu(obj->resv,
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&excl, &count, &shared);
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if (ret)
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return ret;
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for (i = 0; i < count; i++) {
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fence_set_priority(shared[i], attr);
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dma_fence_put(shared[i]);
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}
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kfree(shared);
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} else {
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excl = reservation_object_get_excl_rcu(obj->resv);
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}
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if (excl) {
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fence_set_priority(excl, attr);
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dma_fence_put(excl);
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}
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return 0;
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}
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/**
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* Waits for rendering to the object to be completed
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* @obj: i915 gem object
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* @flags: how to wait (under a lock, for all rendering or just for writes etc)
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* @timeout: how long to wait
|
||||
*/
|
||||
int
|
||||
i915_gem_object_wait(struct drm_i915_gem_object *obj,
|
||||
unsigned int flags,
|
||||
long timeout)
|
||||
{
|
||||
might_sleep();
|
||||
GEM_BUG_ON(timeout < 0);
|
||||
|
||||
timeout = i915_gem_object_wait_reservation(obj->resv, flags, timeout);
|
||||
return timeout < 0 ? timeout : 0;
|
||||
}
|
||||
|
||||
static int
|
||||
i915_gem_phys_pwrite(struct drm_i915_gem_object *obj,
|
||||
struct drm_i915_gem_pwrite *args,
|
||||
|
@ -1097,88 +925,6 @@ void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv)
|
|||
}
|
||||
}
|
||||
|
||||
static unsigned long to_wait_timeout(s64 timeout_ns)
|
||||
{
|
||||
if (timeout_ns < 0)
|
||||
return MAX_SCHEDULE_TIMEOUT;
|
||||
|
||||
if (timeout_ns == 0)
|
||||
return 0;
|
||||
|
||||
return nsecs_to_jiffies_timeout(timeout_ns);
|
||||
}
|
||||
|
||||
/**
|
||||
* i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT
|
||||
* @dev: drm device pointer
|
||||
* @data: ioctl data blob
|
||||
* @file: drm file pointer
|
||||
*
|
||||
* Returns 0 if successful, else an error is returned with the remaining time in
|
||||
* the timeout parameter.
|
||||
* -ETIME: object is still busy after timeout
|
||||
* -ERESTARTSYS: signal interrupted the wait
|
||||
* -ENONENT: object doesn't exist
|
||||
* Also possible, but rare:
|
||||
* -EAGAIN: incomplete, restart syscall
|
||||
* -ENOMEM: damn
|
||||
* -ENODEV: Internal IRQ fail
|
||||
* -E?: The add request failed
|
||||
*
|
||||
* The wait ioctl with a timeout of 0 reimplements the busy ioctl. With any
|
||||
* non-zero timeout parameter the wait ioctl will wait for the given number of
|
||||
* nanoseconds on an object becoming unbusy. Since the wait itself does so
|
||||
* without holding struct_mutex the object may become re-busied before this
|
||||
* function completes. A similar but shorter * race condition exists in the busy
|
||||
* ioctl
|
||||
*/
|
||||
int
|
||||
i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
|
||||
{
|
||||
struct drm_i915_gem_wait *args = data;
|
||||
struct drm_i915_gem_object *obj;
|
||||
ktime_t start;
|
||||
long ret;
|
||||
|
||||
if (args->flags != 0)
|
||||
return -EINVAL;
|
||||
|
||||
obj = i915_gem_object_lookup(file, args->bo_handle);
|
||||
if (!obj)
|
||||
return -ENOENT;
|
||||
|
||||
start = ktime_get();
|
||||
|
||||
ret = i915_gem_object_wait(obj,
|
||||
I915_WAIT_INTERRUPTIBLE |
|
||||
I915_WAIT_PRIORITY |
|
||||
I915_WAIT_ALL,
|
||||
to_wait_timeout(args->timeout_ns));
|
||||
|
||||
if (args->timeout_ns > 0) {
|
||||
args->timeout_ns -= ktime_to_ns(ktime_sub(ktime_get(), start));
|
||||
if (args->timeout_ns < 0)
|
||||
args->timeout_ns = 0;
|
||||
|
||||
/*
|
||||
* Apparently ktime isn't accurate enough and occasionally has a
|
||||
* bit of mismatch in the jiffies<->nsecs<->ktime loop. So patch
|
||||
* things up to make the test happy. We allow up to 1 jiffy.
|
||||
*
|
||||
* This is a regression from the timespec->ktime conversion.
|
||||
*/
|
||||
if (ret == -ETIME && !nsecs_to_jiffies(args->timeout_ns))
|
||||
args->timeout_ns = 0;
|
||||
|
||||
/* Asked to wait beyond the jiffie/scheduler precision? */
|
||||
if (ret == -ETIME && args->timeout_ns)
|
||||
ret = -EAGAIN;
|
||||
}
|
||||
|
||||
i915_gem_object_put(obj);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int wait_for_engines(struct drm_i915_private *i915)
|
||||
{
|
||||
if (wait_for(intel_engines_are_idle(i915), I915_IDLE_ENGINES_TIMEOUT)) {
|
||||
|
|
|
@ -220,16 +220,6 @@ static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m)
|
|||
return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1);
|
||||
}
|
||||
|
||||
static inline unsigned long nsecs_to_jiffies_timeout(const u64 n)
|
||||
{
|
||||
/* nsecs_to_jiffies64() does not guard against overflow */
|
||||
if (NSEC_PER_SEC % HZ &&
|
||||
div_u64(n, NSEC_PER_SEC) >= MAX_JIFFY_OFFSET / HZ)
|
||||
return MAX_JIFFY_OFFSET;
|
||||
|
||||
return min_t(u64, MAX_JIFFY_OFFSET, nsecs_to_jiffies64(n) + 1);
|
||||
}
|
||||
|
||||
/*
|
||||
* If you need to wait X milliseconds between events A and B, but event B
|
||||
* doesn't happen exactly after event A, you record the timestamp (jiffies) of
|
||||
|
|
Loading…
Reference in New Issue