@@ -122,22 +122,14 @@ int __intel_context_do_pin(struct intel_context *ce)
void intel_context_unpin(struct intel_context *ce)
{
- if (likely(atomic_add_unless(&ce->pin_count, -1, 1)))
+ if (!atomic_dec_and_test(&ce->pin_count))
return;
- /* We may be called from inside intel_context_pin() to evict another */
- intel_context_get(ce);
- mutex_lock_nested(&ce->pin_mutex, SINGLE_DEPTH_NESTING);
-
- if (likely(atomic_dec_and_test(&ce->pin_count))) {
- CE_TRACE(ce, "retire\n");
+ CE_TRACE(ce, "unpin\n");
+ ce->ops->unpin(ce);
- ce->ops->unpin(ce);
-
- intel_context_active_release(ce);
- }
-
- mutex_unlock(&ce->pin_mutex);
+ intel_context_get(ce);
+ intel_context_active_release(ce);
intel_context_put(ce);
}
@@ -605,12 +605,15 @@ int i915_active_acquire_preallocate_barrier(struct i915_active *ref,
struct intel_engine_cs *engine)
{
intel_engine_mask_t tmp, mask = engine->mask;
+ struct llist_node *pos = NULL, *next;
struct intel_gt *gt = engine->gt;
- struct llist_node *pos, *next;
int err;
GEM_BUG_ON(i915_active_is_idle(ref));
- GEM_BUG_ON(!llist_empty(&ref->preallocated_barriers));
+
+ /* Wait until the previous preallocation is completed */
+ while (!llist_empty(&ref->preallocated_barriers))
+ cond_resched();
/*
* Preallocate a node for each physical engine supporting the target
@@ -653,16 +656,25 @@ int i915_active_acquire_preallocate_barrier(struct i915_active *ref,
GEM_BUG_ON(rcu_access_pointer(node->base.fence) != ERR_PTR(-EAGAIN));
GEM_BUG_ON(barrier_to_engine(node) != engine);
- llist_add(barrier_to_ll(node), &ref->preallocated_barriers);
+ next = barrier_to_ll(node);
+ next->next = pos;
+ if (!pos)
+ pos = next;
intel_engine_pm_get(engine);
}
+ GEM_BUG_ON(!llist_empty(&ref->preallocated_barriers));
+ llist_add_batch(next, pos, &ref->preallocated_barriers);
+
return 0;
unwind:
- llist_for_each_safe(pos, next, take_preallocated_barriers(ref)) {
+ while (pos) {
struct active_node *node = barrier_from_ll(pos);
+ next = pos->next;
+ pos = next;
+
atomic_dec(&ref->count);
intel_engine_pm_put(barrier_to_engine(node));
The last remaining reason for serialising the pin/unpin of the intel_context is to ensure that our preallocated wakerefs are not consumed too early (i.e. the unpin of the previous phase does not emit the idle barriers for this phase before we even submit). All of the other operations within the context pin/unpin are supposed to be atomic... Therefore, we can reduce the serialisation to being just on the i915_active.preallocated_barriers itself and drop the nested pin_mutex from intel_context_unpin(). Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> --- drivers/gpu/drm/i915/gt/intel_context.c | 18 +++++------------- drivers/gpu/drm/i915/i915_active.c | 20 ++++++++++++++++---- 2 files changed, 21 insertions(+), 17 deletions(-)