#include <linux/debugobjects.h>
#include "gt/intel_engine_pm.h"
+#include "gt/intel_ring.h"
#include "i915_drv.h"
#include "i915_active.h"
#include "i915_globals.h"
-#define BKL(ref) (&(ref)->i915->drm.struct_mutex)
-
/*
* Active refs memory management
*
} global;
struct active_node {
- struct i915_active_request base;
+ struct i915_active_fence base;
struct i915_active *ref;
struct rb_node node;
u64 timeline;
};
static inline struct active_node *
-node_from_active(struct i915_active_request *active)
+node_from_active(struct i915_active_fence *active)
{
return container_of(active, struct active_node, base);
}
#define take_preallocated_barriers(x) llist_del_all(&(x)->preallocated_barriers)
-static inline bool is_barrier(const struct i915_active_request *active)
+static inline bool is_barrier(const struct i915_active_fence *active)
{
- return IS_ERR(rcu_access_pointer(active->request));
+ return IS_ERR(rcu_access_pointer(active->fence));
}
static inline struct llist_node *barrier_to_ll(struct active_node *node)
{
GEM_BUG_ON(!is_barrier(&node->base));
- return (struct llist_node *)&node->base.link;
+ return (struct llist_node *)&node->base.cb.node;
}
static inline struct intel_engine_cs *
__barrier_to_engine(struct active_node *node)
{
- return (struct intel_engine_cs *)READ_ONCE(node->base.link.prev);
+ return (struct intel_engine_cs *)READ_ONCE(node->base.cb.node.prev);
}
static inline struct intel_engine_cs *
static inline struct active_node *barrier_from_ll(struct llist_node *x)
{
return container_of((struct list_head *)x,
- struct active_node, base.link);
+ struct active_node, base.cb.node);
}
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM) && IS_ENABLED(CONFIG_DEBUG_OBJECTS)
static void debug_active_activate(struct i915_active *ref)
{
- debug_object_activate(ref, &active_debug_desc);
+ lockdep_assert_held(&ref->mutex);
+ if (!atomic_read(&ref->count)) /* before the first inc */
+ debug_object_activate(ref, &active_debug_desc);
}
static void debug_active_deactivate(struct i915_active *ref)
{
- debug_object_deactivate(ref, &active_debug_desc);
+ lockdep_assert_held(&ref->mutex);
+ if (!atomic_read(&ref->count)) /* after the last dec */
+ debug_object_deactivate(ref, &active_debug_desc);
}
static void debug_active_fini(struct i915_active *ref)
bool retire = false;
lockdep_assert_held(&ref->mutex);
+ GEM_BUG_ON(i915_active_is_idle(ref));
/* return the unused nodes to our slabcache -- flushing the allocator */
if (atomic_dec_and_test(&ref->count)) {
if (!retire)
return;
+ GEM_BUG_ON(rcu_access_pointer(ref->excl.fence));
rbtree_postorder_for_each_entry_safe(it, n, &root, node) {
- GEM_BUG_ON(i915_active_request_isset(&it->base));
+ GEM_BUG_ON(i915_active_fence_isset(&it->base));
kmem_cache_free(global.slab_cache, it);
}
/* After the final retire, the entire struct may be freed */
if (ref->retire)
ref->retire(ref);
+
+ /* ... except if you wait on it, you must manage your own references! */
+ wake_up_var(ref);
+}
+
+static void
+active_work(struct work_struct *wrk)
+{
+ struct i915_active *ref = container_of(wrk, typeof(*ref), work);
+
+ GEM_BUG_ON(!atomic_read(&ref->count));
+ if (atomic_add_unless(&ref->count, -1, 1))
+ return;
+
+ mutex_lock(&ref->mutex);
+ __active_retire(ref);
}
static void
if (atomic_add_unless(&ref->count, -1, 1))
return;
- /* One active may be flushed from inside the acquire of another */
- mutex_lock_nested(&ref->mutex, SINGLE_DEPTH_NESTING);
+ /* If we are inside interrupt context (fence signaling), defer */
+ if (ref->flags & I915_ACTIVE_RETIRE_SLEEPS ||
+ !mutex_trylock(&ref->mutex)) {
+ queue_work(system_unbound_wq, &ref->work);
+ return;
+ }
+
__active_retire(ref);
}
static void
-node_retire(struct i915_active_request *base, struct i915_request *rq)
+node_retire(struct dma_fence *fence, struct dma_fence_cb *cb)
{
- active_retire(node_from_active(base)->ref);
+ i915_active_fence_cb(fence, cb);
+ active_retire(container_of(cb, struct active_node, base.cb)->ref);
}
-static struct i915_active_request *
+static void
+excl_retire(struct dma_fence *fence, struct dma_fence_cb *cb)
+{
+ i915_active_fence_cb(fence, cb);
+ active_retire(container_of(cb, struct i915_active, excl.cb));
+}
+
+static struct i915_active_fence *
active_instance(struct i915_active *ref, struct intel_timeline *tl)
{
struct active_node *node, *prealloc;
}
node = prealloc;
- i915_active_request_init(&node->base, &tl->mutex, NULL, node_retire);
+ __i915_active_fence_init(&node->base, &tl->mutex, NULL, node_retire);
node->ref = ref;
node->timeline = idx;
return &node->base;
}
-void __i915_active_init(struct drm_i915_private *i915,
- struct i915_active *ref,
+void __i915_active_init(struct i915_active *ref,
int (*active)(struct i915_active *ref),
void (*retire)(struct i915_active *ref),
struct lock_class_key *key)
{
+ unsigned long bits;
+
debug_active_init(ref);
- ref->i915 = i915;
ref->flags = 0;
ref->active = active;
- ref->retire = retire;
+ ref->retire = ptr_unpack_bits(retire, &bits, 2);
+ if (bits & I915_ACTIVE_MAY_SLEEP)
+ ref->flags |= I915_ACTIVE_RETIRE_SLEEPS;
+
ref->tree = RB_ROOT;
ref->cache = NULL;
init_llist_head(&ref->preallocated_barriers);
atomic_set(&ref->count, 0);
__mutex_init(&ref->mutex, "i915_active", key);
+ __i915_active_fence_init(&ref->excl, &ref->mutex, NULL, excl_retire);
+ INIT_WORK(&ref->work, active_work);
}
static bool ____active_del_barrier(struct i915_active *ref,
int i915_active_ref(struct i915_active *ref,
struct intel_timeline *tl,
- struct i915_request *rq)
+ struct dma_fence *fence)
{
- struct i915_active_request *active;
+ struct i915_active_fence *active;
int err;
lockdep_assert_held(&tl->mutex);
* request that we want to emit on the kernel_context.
*/
__active_del_barrier(ref, node_from_active(active));
- RCU_INIT_POINTER(active->request, NULL);
- INIT_LIST_HEAD(&active->link);
- } else {
- if (!i915_active_request_isset(active))
- atomic_inc(&ref->count);
+ RCU_INIT_POINTER(active->fence, NULL);
+ atomic_dec(&ref->count);
}
- GEM_BUG_ON(!atomic_read(&ref->count));
- __i915_active_request_set(active, rq);
+ if (!__i915_active_fence_set(active, fence))
+ atomic_inc(&ref->count);
out:
i915_active_release(ref);
return err;
}
+void i915_active_set_exclusive(struct i915_active *ref, struct dma_fence *f)
+{
+ /* We expect the caller to manage the exclusive timeline ordering */
+ GEM_BUG_ON(i915_active_is_idle(ref));
+
+ /*
+ * As we don't know which mutex the caller is using, we told a small
+ * lie to the debug code that it is using the i915_active.mutex;
+ * and now we must stick to that lie.
+ */
+ mutex_acquire(&ref->mutex.dep_map, 0, 0, _THIS_IP_);
+ if (!__i915_active_fence_set(&ref->excl, f))
+ atomic_inc(&ref->count);
+ mutex_release(&ref->mutex.dep_map, 0, _THIS_IP_);
+}
+
+bool i915_active_acquire_if_busy(struct i915_active *ref)
+{
+ debug_active_assert(ref);
+ return atomic_add_unless(&ref->count, 1, 0);
+}
+
int i915_active_acquire(struct i915_active *ref)
{
int err;
- debug_active_assert(ref);
- if (atomic_add_unless(&ref->count, 1, 0))
+ if (i915_active_acquire_if_busy(ref))
return 0;
err = mutex_lock_interruptible(&ref->mutex);
active_retire(ref);
}
-static void __active_ungrab(struct i915_active *ref)
+static void enable_signaling(struct i915_active_fence *active)
{
- clear_and_wake_up_bit(I915_ACTIVE_GRAB_BIT, &ref->flags);
-}
+ struct dma_fence *fence;
-bool i915_active_trygrab(struct i915_active *ref)
-{
- debug_active_assert(ref);
-
- if (test_and_set_bit(I915_ACTIVE_GRAB_BIT, &ref->flags))
- return false;
-
- if (!atomic_add_unless(&ref->count, 1, 0)) {
- __active_ungrab(ref);
- return false;
- }
-
- return true;
-}
-
-void i915_active_ungrab(struct i915_active *ref)
-{
- GEM_BUG_ON(!test_bit(I915_ACTIVE_GRAB_BIT, &ref->flags));
+ fence = i915_active_fence_get(active);
+ if (!fence)
+ return;
- active_retire(ref);
- __active_ungrab(ref);
+ dma_fence_enable_sw_signaling(fence);
+ dma_fence_put(fence);
}
int i915_active_wait(struct i915_active *ref)
{
struct active_node *it, *n;
- int err;
+ int err = 0;
might_sleep();
- might_lock(&ref->mutex);
-
- if (i915_active_is_idle(ref))
- return 0;
-
- err = mutex_lock_interruptible(&ref->mutex);
- if (err)
- return err;
- if (!atomic_add_unless(&ref->count, 1, 0)) {
- mutex_unlock(&ref->mutex);
+ if (!i915_active_acquire_if_busy(ref))
return 0;
- }
+ /* Flush lazy signals */
+ enable_signaling(&ref->excl);
rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node) {
- if (is_barrier(&it->base)) { /* unconnected idle-barrier */
- err = -EBUSY;
- break;
- }
+ if (is_barrier(&it->base)) /* unconnected idle barrier */
+ continue;
- err = i915_active_request_retire(&it->base, BKL(ref));
- if (err)
- break;
+ enable_signaling(&it->base);
}
+ /* Any fence added after the wait begins will not be auto-signaled */
- __active_retire(ref);
+ i915_active_release(ref);
if (err)
return err;
- if (wait_on_bit(&ref->flags, I915_ACTIVE_GRAB_BIT, TASK_KILLABLE))
+ if (wait_var_event_interruptible(ref, i915_active_is_idle(ref)))
return -EINTR;
- if (!i915_active_is_idle(ref))
- return -EBUSY;
-
return 0;
}
-int i915_request_await_active_request(struct i915_request *rq,
- struct i915_active_request *active)
-{
- struct i915_request *barrier =
- i915_active_request_raw(active, &rq->i915->drm.struct_mutex);
-
- return barrier ? i915_request_await_dma_fence(rq, &barrier->fence) : 0;
-}
-
int i915_request_await_active(struct i915_request *rq, struct i915_active *ref)
{
- struct active_node *it, *n;
- int err;
-
- if (RB_EMPTY_ROOT(&ref->tree))
- return 0;
+ int err = 0;
- /* await allocates and so we need to avoid hitting the shrinker */
- err = i915_active_acquire(ref);
- if (err)
- return err;
+ if (rcu_access_pointer(ref->excl.fence)) {
+ struct dma_fence *fence;
- mutex_lock(&ref->mutex);
- rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node) {
- err = i915_request_await_active_request(rq, &it->base);
- if (err)
- break;
+ rcu_read_lock();
+ fence = dma_fence_get_rcu_safe(&ref->excl.fence);
+ rcu_read_unlock();
+ if (fence) {
+ err = i915_request_await_dma_fence(rq, fence);
+ dma_fence_put(fence);
+ }
}
- mutex_unlock(&ref->mutex);
- i915_active_release(ref);
+ /* In the future we may choose to await on all fences */
+
return err;
}
void i915_active_fini(struct i915_active *ref)
{
debug_active_fini(ref);
- GEM_BUG_ON(!RB_EMPTY_ROOT(&ref->tree));
GEM_BUG_ON(atomic_read(&ref->count));
+ GEM_BUG_ON(work_pending(&ref->work));
+ GEM_BUG_ON(!RB_EMPTY_ROOT(&ref->tree));
mutex_destroy(&ref->mutex);
}
#endif
static inline bool is_idle_barrier(struct active_node *node, u64 idx)
{
- return node->timeline == idx && !i915_active_request_isset(&node->base);
+ return node->timeline == idx && !i915_active_fence_isset(&node->base);
}
static struct active_node *reuse_idle_barrier(struct i915_active *ref, u64 idx)
int i915_active_acquire_preallocate_barrier(struct i915_active *ref,
struct intel_engine_cs *engine)
{
- struct drm_i915_private *i915 = engine->i915;
intel_engine_mask_t tmp, mask = engine->mask;
+ 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));
/*
* We can then use the preallocated nodes in
* i915_active_acquire_barrier()
*/
- for_each_engine_masked(engine, i915, mask, tmp) {
+ for_each_engine_masked(engine, gt, mask, tmp) {
u64 idx = engine->kernel_context->timeline->fence_context;
struct active_node *node;
node->base.lock =
&engine->kernel_context->timeline->mutex;
#endif
- RCU_INIT_POINTER(node->base.request, NULL);
- node->base.retire = node_retire;
+ RCU_INIT_POINTER(node->base.fence, NULL);
+ node->base.cb.func = node_retire;
node->timeline = idx;
node->ref = ref;
}
- if (!i915_active_request_isset(&node->base)) {
+ if (!i915_active_fence_isset(&node->base)) {
/*
* Mark this as being *our* unconnected proto-node.
*
* and then we can use the rb_node and list pointers
* for our tracking of the pending barrier.
*/
- RCU_INIT_POINTER(node->base.request, ERR_PTR(-EAGAIN));
- node->base.link.prev = (void *)engine;
+ RCU_INIT_POINTER(node->base.fence, ERR_PTR(-EAGAIN));
+ node->base.cb.node.prev = (void *)engine;
atomic_inc(&ref->count);
}
rb_link_node(&node->node, parent, p);
rb_insert_color(&node->node, &ref->tree);
+ GEM_BUG_ON(!intel_engine_pm_is_awake(engine));
llist_add(barrier_to_ll(node), &engine->barrier_tasks);
intel_engine_pm_put(engine);
}
{
struct intel_engine_cs *engine = rq->engine;
struct llist_node *node, *next;
+ unsigned long flags;
GEM_BUG_ON(intel_engine_is_virtual(engine));
- GEM_BUG_ON(rq->timeline != engine->kernel_context->timeline);
+ GEM_BUG_ON(i915_request_timeline(rq) != engine->kernel_context->timeline);
+ node = llist_del_all(&engine->barrier_tasks);
+ if (!node)
+ return;
/*
* Attach the list of proto-fences to the in-flight request such
* that the parent i915_active will be released when this request
* is retired.
*/
- llist_for_each_safe(node, next, llist_del_all(&engine->barrier_tasks)) {
- RCU_INIT_POINTER(barrier_from_ll(node)->base.request, rq);
+ spin_lock_irqsave(&rq->lock, flags);
+ llist_for_each_safe(node, next, node) {
+ RCU_INIT_POINTER(barrier_from_ll(node)->base.fence, &rq->fence);
smp_wmb(); /* serialise with reuse_idle_barrier */
- list_add_tail((struct list_head *)node, &rq->active_list);
+ list_add_tail((struct list_head *)node, &rq->fence.cb_list);
}
+ spin_unlock_irqrestore(&rq->lock, flags);
}
-int i915_active_request_set(struct i915_active_request *active,
- struct i915_request *rq)
+#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
+#define active_is_held(active) lockdep_is_held((active)->lock)
+#else
+#define active_is_held(active) true
+#endif
+
+/*
+ * __i915_active_fence_set: Update the last active fence along its timeline
+ * @active: the active tracker
+ * @fence: the new fence (under construction)
+ *
+ * Records the new @fence as the last active fence along its timeline in
+ * this active tracker, moving the tracking callbacks from the previous
+ * fence onto this one. Returns the previous fence (if not already completed),
+ * which the caller must ensure is executed before the new fence. To ensure
+ * that the order of fences within the timeline of the i915_active_fence is
+ * maintained, it must be locked by the caller.
+ */
+struct dma_fence *
+__i915_active_fence_set(struct i915_active_fence *active,
+ struct dma_fence *fence)
{
- int err;
+ struct dma_fence *prev;
+ unsigned long flags;
+
+ /* NB: must be serialised by an outer timeline mutex (active->lock) */
+ spin_lock_irqsave(fence->lock, flags);
+ GEM_BUG_ON(test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags));
+
+ prev = rcu_dereference_protected(active->fence, active_is_held(active));
+ if (prev) {
+ GEM_BUG_ON(prev == fence);
+ spin_lock_nested(prev->lock, SINGLE_DEPTH_NESTING);
+ __list_del_entry(&active->cb.node);
+ spin_unlock(prev->lock); /* serialise with prev->cb_list */
+
+ /*
+ * active->fence is reset by the callback from inside
+ * interrupt context. We need to serialise our list
+ * manipulation with the fence->lock to prevent the prev
+ * being lost inside an interrupt (it can't be replaced as
+ * no other caller is allowed to enter __i915_active_fence_set
+ * as we hold the timeline lock). After serialising with
+ * the callback, we need to double check which ran first,
+ * our list_del() [decoupling prev from the callback] or
+ * the callback...
+ */
+ prev = rcu_access_pointer(active->fence);
+ }
+
+ rcu_assign_pointer(active->fence, fence);
+ list_add_tail(&active->cb.node, &fence->cb_list);
+
+ spin_unlock_irqrestore(fence->lock, flags);
+
+ return prev;
+}
+
+int i915_active_fence_set(struct i915_active_fence *active,
+ struct i915_request *rq)
+{
+ struct dma_fence *fence;
+ int err = 0;
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
lockdep_assert_held(active->lock);
#endif
- /* Must maintain ordering wrt previous active requests */
- err = i915_request_await_active_request(rq, active);
- if (err)
- return err;
+ /* Must maintain timeline ordering wrt previous active requests */
+ rcu_read_lock();
+ fence = __i915_active_fence_set(active, &rq->fence);
+ if (fence) /* but the previous fence may not belong to that timeline! */
+ fence = dma_fence_get_rcu(fence);
+ rcu_read_unlock();
+ if (fence) {
+ err = i915_request_await_dma_fence(rq, fence);
+ dma_fence_put(fence);
+ }
- __i915_active_request_set(active, rq);
- return 0;
+ return err;
}
-void i915_active_retire_noop(struct i915_active_request *active,
- struct i915_request *request)
+void i915_active_noop(struct dma_fence *fence, struct dma_fence_cb *cb)
{
- /* Space left intentionally blank */
+ i915_active_fence_cb(fence, cb);
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
projects / linux-2.6-block.git / blobdiff