drm/i915: Allow asynchronous waits on the i915_active barriers

Allow the caller to also wait upon the barriers stored in i915_active.

v2: Hook up i915_request_await_active(I915_ACTIVE_AWAIT_BARRIER) as well
for completeness, and avoid the lazy GEM_BUG_ON()!

v3: Pull flush_lazy_signals() under the active-ref protection as it too
walks the rbtree and so we must be careful that we do not free it as we
iterate.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200406155840.1728-2-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2020-04-06 16:58:39 +01:00
parent 442dbc5c68
commit 3b0a05792e
2 changed files with 65 additions and 11 deletions

View File

@ -542,35 +542,88 @@ static int __await_active(struct i915_active_fence *active,
return 0;
}
struct wait_barrier {
struct wait_queue_entry base;
struct i915_active *ref;
};
static int
barrier_wake(wait_queue_entry_t *wq, unsigned int mode, int flags, void *key)
{
struct wait_barrier *wb = container_of(wq, typeof(*wb), base);
if (i915_active_is_idle(wb->ref)) {
list_del(&wq->entry);
i915_sw_fence_complete(wq->private);
kfree(wq);
}
return 0;
}
static int __await_barrier(struct i915_active *ref, struct i915_sw_fence *fence)
{
struct wait_barrier *wb;
wb = kmalloc(sizeof(*wb), GFP_KERNEL);
if (unlikely(!wb))
return -ENOMEM;
GEM_BUG_ON(i915_active_is_idle(ref));
if (!i915_sw_fence_await(fence)) {
kfree(wb);
return -EINVAL;
}
wb->base.flags = 0;
wb->base.func = barrier_wake;
wb->base.private = fence;
wb->ref = ref;
add_wait_queue(__var_waitqueue(ref), &wb->base);
return 0;
}
static int await_active(struct i915_active *ref,
unsigned int flags,
int (*fn)(void *arg, struct dma_fence *fence),
void *arg)
void *arg, struct i915_sw_fence *barrier)
{
int err = 0;
if (!i915_active_acquire_if_busy(ref))
return 0;
if (flags & I915_ACTIVE_AWAIT_EXCL &&
rcu_access_pointer(ref->excl.fence)) {
err = __await_active(&ref->excl, fn, arg);
if (err)
return err;
goto out;
}
if (flags & I915_ACTIVE_AWAIT_ACTIVE &&
i915_active_acquire_if_busy(ref)) {
if (flags & I915_ACTIVE_AWAIT_ACTIVE) {
struct active_node *it, *n;
rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node) {
err = __await_active(&it->base, fn, arg);
if (err)
break;
goto out;
}
i915_active_release(ref);
if (err)
return err;
}
return 0;
if (flags & I915_ACTIVE_AWAIT_BARRIER) {
err = flush_lazy_signals(ref);
if (err)
goto out;
err = __await_barrier(ref, barrier);
if (err)
goto out;
}
out:
i915_active_release(ref);
return err;
}
static int rq_await_fence(void *arg, struct dma_fence *fence)
@ -582,7 +635,7 @@ int i915_request_await_active(struct i915_request *rq,
struct i915_active *ref,
unsigned int flags)
{
return await_active(ref, flags, rq_await_fence, rq);
return await_active(ref, flags, rq_await_fence, rq, &rq->submit);
}
static int sw_await_fence(void *arg, struct dma_fence *fence)
@ -595,7 +648,7 @@ int i915_sw_fence_await_active(struct i915_sw_fence *fence,
struct i915_active *ref,
unsigned int flags)
{
return await_active(ref, flags, sw_await_fence, fence);
return await_active(ref, flags, sw_await_fence, fence, fence);
}
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)

View File

@ -195,6 +195,7 @@ int i915_request_await_active(struct i915_request *rq,
unsigned int flags);
#define I915_ACTIVE_AWAIT_EXCL BIT(0)
#define I915_ACTIVE_AWAIT_ACTIVE BIT(1)
#define I915_ACTIVE_AWAIT_BARRIER BIT(2)
int i915_active_acquire(struct i915_active *ref);
bool i915_active_acquire_if_busy(struct i915_active *ref);