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gpu / command_buffer / service / sync_point_manager.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif
#include "gpu/command_buffer/service/sync_point_manager.h"
#include <limits.h>
#include <stddef.h>
#include <stdint.h>
#include "base/functional/bind.h"
#include "base/location.h"
#include "base/logging.h"
#include "base/memory/scoped_refptr.h"
#include "base/metrics/histogram_macros.h"
#include "base/synchronization/lock.h"
#include "gpu/config/gpu_finch_features.h"
namespace gpu {
SyncPointOrderData::OrderFence::OrderFence(
uint32_t order,
uint64_t release,
scoped_refptr<SyncPointClientState> state,
uint64_t callback_id)
: order_num(order),
fence_release(release),
client_state(std::move(state)),
callback_id(callback_id) {}
SyncPointOrderData::OrderFence::OrderFence(const OrderFence& other) = default;
SyncPointOrderData::OrderFence::~OrderFence() = default;
SyncPointOrderData::SyncPointOrderData(SyncPointManager* sync_point_manager,
SequenceId sequence_id)
: sync_point_manager_(sync_point_manager), sequence_id_(sequence_id) {
// Creation could happen outside of GPU thread.
DETACH_FROM_THREAD(processing_thread_checker_);
}
SyncPointOrderData::~SyncPointOrderData() {
DCHECK(destroyed_);
}
void SyncPointOrderData::Destroy() {
// Because of circular references between the SyncPointOrderData and
// SyncPointClientState, we must remove the references on destroy. Releasing
// the fence syncs in the order fence queue would be redundant at this point
// because they are assumed to be released on the destruction of the
// SyncPointClientState.
{
base::AutoLock lock(lock_);
DCHECK(!destroyed_);
destroyed_ = true;
while (!order_fence_queue_.empty()) {
order_fence_queue_.pop();
}
}
// Now what we've marked ourselves as destroyed_, we can finally remove
// ourselves from the manager's map.
sync_point_manager_->RemoveSyncPointOrderData(base::WrapRefCounted(this));
}
uint32_t SyncPointOrderData::GenerateUnprocessedOrderNumber() {
base::AutoLock auto_lock(lock_);
DCHECK(!destroyed_);
last_unprocessed_order_num_ = sync_point_manager_->GenerateOrderNumber();
unprocessed_order_nums_.push(last_unprocessed_order_num_);
return last_unprocessed_order_num_;
}
void SyncPointOrderData::BeginProcessingOrderNumber(uint32_t order_num) {
DCHECK(processing_thread_checker_.CalledOnValidThread());
DCHECK_GE(order_num, current_order_num_);
// Use thread-safe accessors here because |processed_order_num_| and
// |unprocessed_order_num_| are protected by a lock.
DCHECK_GT(order_num, processed_order_num());
DCHECK_LE(order_num, unprocessed_order_num());
current_order_num_ = order_num;
paused_ = false;
}
void SyncPointOrderData::PauseProcessingOrderNumber(uint32_t order_num) {
DCHECK(processing_thread_checker_.CalledOnValidThread());
DCHECK_EQ(current_order_num_, order_num);
DCHECK(!paused_);
paused_ = true;
}
void SyncPointOrderData::FinishProcessingOrderNumber(uint32_t order_num) {
DCHECK(processing_thread_checker_.CalledOnValidThread());
DCHECK_EQ(current_order_num_, order_num);
DCHECK(!paused_);
// Catch invalid waits which were waiting on fence syncs that do not exist.
// When we end processing an order number, we should release any fence syncs
// which were suppose to be released during this order number.
// Release without the lock to avoid possible deadlocks.
std::vector<OrderFence> ensure_releases;
{
base::AutoLock auto_lock(lock_);
DCHECK_GT(order_num, processed_order_num_);
processed_order_num_ = order_num;
DCHECK(!unprocessed_order_nums_.empty());
DCHECK_EQ(order_num, unprocessed_order_nums_.front());
unprocessed_order_nums_.pop();
if (!sync_point_manager_->graph_validation_enabled()) {
uint32_t next_order_num = 0;
if (!unprocessed_order_nums_.empty()) {
next_order_num = unprocessed_order_nums_.front();
}
while (!order_fence_queue_.empty()) {
const OrderFence& order_fence = order_fence_queue_.top();
// It's possible for the fence's order number to equal next order
// number. This happens when the wait was enqueued with an order number
// greater than the last unprocessed order number. So don't release the
// fence yet.
if (!next_order_num || order_fence.order_num < next_order_num) {
ensure_releases.push_back(order_fence);
order_fence_queue_.pop();
continue;
}
break;
}
}
}
for (OrderFence& order_fence : ensure_releases) {
order_fence.client_state->EnsureWaitReleased(order_fence.fence_release,
order_fence.callback_id);
}
}
uint64_t SyncPointOrderData::ValidateReleaseOrderNumber(
scoped_refptr<SyncPointClientState> client_state,
uint32_t wait_order_num,
uint64_t fence_release) {
client_state->fence_sync_lock_.AssertAcquired(); // Can't statically check.
base::AutoLock lock(lock_);
if (destroyed_)
return 0;
if (sync_point_manager_->graph_validation_enabled()) {
return ++current_callback_id_;
}
// We should have unprocessed order numbers which could potentially release
// this fence.
if (unprocessed_order_nums_.empty()) {
return 0;
}
// We should have an unprocessed order number lower than the wait order
// number for the wait to be valid. It's not possible for wait order number to
// equal next unprocessed order number, but we handle that defensively.
if (wait_order_num <= unprocessed_order_nums_.front()) {
return 0;
}
// So far it could be valid, but add an order fence guard to be sure it
// gets released eventually.
uint32_t expected_order_num =
std::min(unprocessed_order_nums_.back(), wait_order_num);
uint64_t callback_id = ++current_callback_id_;
order_fence_queue_.emplace(expected_order_num, fence_release,
std::move(client_state), callback_id);
return callback_id;
}
SyncPointClientState::ReleaseCallback::ReleaseCallback(
uint64_t release,
base::OnceClosure callback,
uint64_t callback_id)
: release_count(release),
callback_closure(std::move(callback)),
callback_id(callback_id) {}
SyncPointClientState::ReleaseCallback::ReleaseCallback(
ReleaseCallback&& other) = default;
SyncPointClientState::ReleaseCallback::~ReleaseCallback() = default;
SyncPointClientState::SyncPointClientState(
SyncPointManager* sync_point_manager,
scoped_refptr<SyncPointOrderData> order_data,
CommandBufferNamespace namespace_id,
CommandBufferId command_buffer_id)
: sync_point_manager_(sync_point_manager),
order_data_(std::move(order_data)),
namespace_id_(namespace_id),
command_buffer_id_(command_buffer_id) {}
SyncPointClientState::~SyncPointClientState() {
DCHECK_EQ(UINT64_MAX, fence_sync_release_);
}
void SyncPointClientState::Destroy() {
sync_point_manager_->DestroySyncPointClientState(base::WrapRefCounted(this));
}
std::vector<base::OnceClosure>
SyncPointClientState::DestroyAndReturnCallbacks() {
base::AutoLock lock(fence_sync_lock_);
DCHECK(!destroyed_.IsSet());
destroyed_.Set();
std::vector<base::OnceClosure> callbacks;
callbacks.reserve(release_callback_queue_.size());
while (!release_callback_queue_.empty()) {
callbacks.push_back(
std::move(const_cast<ReleaseCallback&>(release_callback_queue_.top())
.callback_closure));
release_callback_queue_.pop();
}
fence_sync_release_ = UINT64_MAX;
return callbacks;
}
bool SyncPointClientState::IsFenceSyncReleased(uint64_t release) {
base::AutoLock lock(fence_sync_lock_);
return release <= fence_sync_release_;
}
bool SyncPointClientState::WaitForRelease(uint64_t release,
uint32_t wait_order_num,
base::OnceClosure callback) {
// Lock must be held the whole time while we validate otherwise it could be
// released while we are checking.
base::AutoLock auto_lock(fence_sync_lock_);
// Already released, do not run the callback.
if (release <= fence_sync_release_)
return false;
uint64_t callback_id =
order_data_->ValidateReleaseOrderNumber(this, wait_order_num, release);
if (callback_id) {
// Add the callback which will be called upon release.
release_callback_queue_.emplace(release, std::move(callback), callback_id);
return true;
}
DLOG(ERROR)
<< "Client waiting on non-existent sync token or sequence destroyed";
return false;
}
void SyncPointClientState::EnsureFenceSyncReleased(uint64_t release,
ReleaseCause cause) {
// Call callbacks without the lock to avoid possible deadlocks.
std::vector<base::OnceClosure> callback_list;
{
base::AutoLock auto_lock(fence_sync_lock_);
// Check that in the ReleaseCause::kExplicitClientRelease case, the
// release count must be larger than previously-seen release count from the
// client.
//
// For the ReleaseCause::kTaskCompletionRelease case, we relax the check a
// little bit to allow the release count to be "no less than"
// previously-seen release count from the client. That is because currently
// for some clients consecutive tasks may specify the same task release
// number, if no new fence sync is inserted.
//
// Please also note that if forceful release has happened to resolve invalid
// waits, the current `fence_sync_release_` may be larger than `release`.
if ((cause == ReleaseCause::kExplicitClientRelease &&
release <= client_fence_sync_release_) ||
(cause == ReleaseCause::kTaskCompletionRelease &&
release < client_fence_sync_release_)) {
static constexpr char error_message[] =
"Client attempted to release a fence sync that has been released.";
if (!sync_point_manager_->suppress_fatal_log_for_testing()) {
LOG(DFATAL) << error_message;
} else {
LOG(ERROR) << error_message;
}
}
if (cause == ReleaseCause::kExplicitClientRelease ||
cause == ReleaseCause::kTaskCompletionRelease) {
client_fence_sync_release_ = release;
}
if (release <= fence_sync_release_) {
DCHECK(release_callback_queue_.empty() ||
release_callback_queue_.top().release_count > release);
return;
}
fence_sync_release_ = release;
while (!release_callback_queue_.empty() &&
release_callback_queue_.top().release_count <= release) {
ReleaseCallback& release_callback =
const_cast<ReleaseCallback&>(release_callback_queue_.top());
callback_list.emplace_back(std::move(release_callback.callback_closure));
release_callback_queue_.pop();
}
}
for (base::OnceClosure& closure : callback_list)
std::move(closure).Run();
}
void SyncPointClientState::EnsureWaitReleased(uint64_t release,
uint64_t callback_id) {
// This method should not be called if graph-based validation is enabled.
DCHECK(!sync_point_manager_->graph_validation_enabled());
// Call callbacks without the lock to avoid possible deadlocks.
base::OnceClosure callback;
{
base::AutoLock auto_lock(fence_sync_lock_);
if (release <= fence_sync_release_)
return;
std::vector<ReleaseCallback> popped_callbacks;
popped_callbacks.reserve(release_callback_queue_.size());
while (!release_callback_queue_.empty() &&
release_callback_queue_.top().release_count <= release) {
ReleaseCallback& top_item =
const_cast<ReleaseCallback&>(release_callback_queue_.top());
if (top_item.release_count == release &&
top_item.callback_id == callback_id) {
// Call the callback, and discard this item from the callback queue.
callback = std::move(top_item.callback_closure);
} else {
// Store the item to be placed back into the callback queue later.
popped_callbacks.emplace_back(std::move(top_item));
}
release_callback_queue_.pop();
}
// Add back in popped items.
for (ReleaseCallback& popped_callback : popped_callbacks) {
release_callback_queue_.emplace(std::move(popped_callback));
}
}
if (callback) {
// This effectively releases the wait without releasing the fence.
DLOG(ERROR) << "Client did not release sync token as expected";
std::move(callback).Run();
}
}
SyncPointManager::SyncPointManager()
: graph_validation_enabled_(features::IsSyncPointGraphValidationEnabled()) {
// Order number 0 is treated as invalid, so increment the generator and return
// positive order numbers in GenerateOrderNumber() from now on.
order_num_generator_.GetNext();
}
SyncPointManager::~SyncPointManager() {
DCHECK(order_data_map_.empty());
for (const ClientStateMap& client_state_map : client_state_maps_)
DCHECK(client_state_map.empty());
}
scoped_refptr<SyncPointOrderData> SyncPointManager::CreateSyncPointOrderData() {
base::AutoLock auto_lock(lock_);
SequenceId sequence_id = sequence_id_generator_.GenerateNextId();
scoped_refptr<SyncPointOrderData> order_data =
new SyncPointOrderData(this, sequence_id);
DCHECK(!order_data_map_.count(sequence_id));
order_data_map_.insert(std::make_pair(sequence_id, order_data));
return order_data;
}
void SyncPointManager::RemoveSyncPointOrderData(
scoped_refptr<SyncPointOrderData> order_data) {
base::AutoLock auto_lock(lock_);
// destroyed_ is the flag used to check the validity of SyncPointOrderData. It
// must be destroyed before removing it from order_data_map_.
DCHECK(TS_UNCHECKED_READ(order_data->destroyed_));
const int num_erased = order_data_map_.erase(order_data->sequence_id());
DCHECK_EQ(num_erased, 1);
}
scoped_refptr<SyncPointClientState>
SyncPointManager::CreateSyncPointClientState(
CommandBufferNamespace namespace_id,
CommandBufferId command_buffer_id,
SequenceId sequence_id) {
base::AutoLock auto_lock(lock_);
scoped_refptr<SyncPointOrderData> order_data =
GetSyncPointOrderData(sequence_id);
scoped_refptr<SyncPointClientState> client_state = new SyncPointClientState(
this, order_data, namespace_id, command_buffer_id);
DCHECK_GE(namespace_id, 0);
DCHECK_LT(static_cast<size_t>(namespace_id), std::size(client_state_maps_));
const auto [_, inserted] = client_state_maps_[namespace_id].insert(
std::make_pair(command_buffer_id, client_state));
CHECK(inserted);
return client_state;
}
void SyncPointManager::DestroySyncPointClientState(
scoped_refptr<SyncPointClientState> client_state) {
std::vector<base::OnceClosure> callbacks;
// First, destroy the client state (which marks it as destroyed). Its pending
// callbacks will be executed after we remove the client state from our map.
{
base::AutoLock lock(lock_);
callbacks = client_state->DestroyAndReturnCallbacks();
const CommandBufferNamespace namespace_id = client_state->namespace_id();
const CommandBufferId command_buffer_id = client_state->command_buffer_id();
DCHECK_GE(namespace_id, 0);
DCHECK_LT(static_cast<size_t>(namespace_id), std::size(client_state_maps_));
DCHECK(client_state_maps_[namespace_id].count(command_buffer_id));
client_state_maps_[namespace_id].erase(command_buffer_id);
}
// At this point, if SyncPointClientState::Wait is called, it will (correctly)
// return false because client_state is removed from our map. It is safe to
// call the callbacks.
for (auto& closure : callbacks) {
std::move(closure).Run();
}
}
void SyncPointManager::EnsureFenceSyncReleased(const SyncToken& release,
ReleaseCause cause) {
scoped_refptr<SyncPointClientState> client_state;
{
base::AutoLock lock(lock_);
if (metrics_subsampler_.ShouldSample(0.01)) {
if (graph_validation_enabled_) {
UMA_HISTOGRAM_ENUMERATION("GPU.FenceSyncRelease.GraphValidation.Cause",
cause);
} else {
UMA_HISTOGRAM_ENUMERATION("GPU.FenceSyncrelease.OrderValidation.Cause",
cause);
}
}
if (cause == ReleaseCause::kForceRelease) {
if (graph_validation_enabled_) {
UMA_HISTOGRAM_ENUMERATION(
"GPU.FenceSyncRelease.GraphValidation.ForceReleaseNamespace",
release.namespace_id(),
CommandBufferNamespace::NUM_COMMAND_BUFFER_NAMESPACES);
} else {
NOTREACHED() << "ReleaseCause::kForceRelease is only used in "
"graph-based validation.";
}
}
client_state = GetSyncPointClientState(release.namespace_id(),
release.command_buffer_id());
}
if (client_state) {
// This must be called without holding `lock_`, because it may call release
// callbacks which are not supposed to be called under `lock_`.
client_state->EnsureFenceSyncReleased(release.release_count(), cause);
}
}
bool SyncPointManager::IsSyncTokenReleased(const SyncToken& sync_token) {
base::AutoLock auto_lock(lock_);
scoped_refptr<SyncPointClientState> release_state = GetSyncPointClientState(
sync_token.namespace_id(), sync_token.command_buffer_id());
// release_state can't be destroyed while we hold lock_.
if (release_state)
return release_state->IsFenceSyncReleased(sync_token.release_count());
return true;
}
SequenceId SyncPointManager::GetSyncTokenReleaseSequenceId(
const SyncToken& sync_token) {
base::AutoLock auto_lock(lock_);
return GetSyncTokenReleaseSequenceIdInternal(sync_token);
}
SequenceId SyncPointManager::GetSyncTokenReleaseSequenceIdInternal(
const SyncToken& sync_token) {
scoped_refptr<SyncPointClientState> client_state = GetSyncPointClientState(
sync_token.namespace_id(), sync_token.command_buffer_id());
if (client_state) {
return client_state->sequence_id();
}
return SequenceId();
}
uint32_t SyncPointManager::GetProcessedOrderNum() const {
base::AutoLock auto_lock(lock_);
uint32_t processed_order_num = 0;
for (const auto& kv : order_data_map_) {
processed_order_num =
std::max(processed_order_num, kv.second->processed_order_num());
}
return processed_order_num;
}
uint32_t SyncPointManager::GetUnprocessedOrderNum() const {
base::AutoLock auto_lock(lock_);
uint32_t unprocessed_order_num = 0;
for (const auto& kv : order_data_map_) {
unprocessed_order_num =
std::max(unprocessed_order_num, kv.second->unprocessed_order_num());
}
return unprocessed_order_num;
}
bool SyncPointManager::Wait(const SyncToken& sync_token,
SequenceId sequence_id,
uint32_t wait_order_num,
base::OnceClosure callback) {
base::AutoLock auto_lock(lock_);
if (sequence_id == GetSyncTokenReleaseSequenceIdInternal(sync_token)) {
return false;
}
scoped_refptr<SyncPointClientState> release_state = GetSyncPointClientState(
sync_token.namespace_id(), sync_token.command_buffer_id());
if (release_state &&
release_state->WaitForRelease(sync_token.release_count(), wait_order_num,
std::move(callback))) {
return true;
}
// Do not run callback if wait is invalid.
return false;
}
uint32_t SyncPointManager::GenerateOrderNumber() {
return order_num_generator_.GetNext();
}
scoped_refptr<SyncPointClientState> SyncPointManager::GetSyncPointClientState(
CommandBufferNamespace namespace_id,
CommandBufferId command_buffer_id) {
if (namespace_id >= 0) {
DCHECK_LT(static_cast<size_t>(namespace_id), std::size(client_state_maps_));
ClientStateMap& client_state_map = client_state_maps_[namespace_id];
auto it = client_state_map.find(command_buffer_id);
if (it != client_state_map.end())
return it->second;
}
return nullptr;
}
scoped_refptr<SyncPointOrderData> SyncPointManager::GetSyncPointOrderData(
SequenceId sequence_id) {
auto it = order_data_map_.find(sequence_id);
if (it != order_data_map_.end())
return it->second;
return nullptr;
}
} // namespace gpu