Use Task in ConstraintBuilder2D (#1118)

master
gaschler 2018-04-26 12:33:36 +02:00 committed by Wally B. Feed
parent 666095cb41
commit c46fe073b4
2 changed files with 123 additions and 132 deletions

View File

@ -58,14 +58,17 @@ ConstraintBuilder2D::ConstraintBuilder2D(
common::ThreadPoolInterface* const thread_pool)
: options_(options),
thread_pool_(thread_pool),
finish_node_task_(common::make_unique<common::Task>()),
when_done_task_(common::make_unique<common::Task>()),
sampler_(options.sampling_ratio()),
ceres_scan_matcher_(options.ceres_scan_matcher_options()) {}
ConstraintBuilder2D::~ConstraintBuilder2D() {
common::MutexLocker locker(&mutex_);
CHECK_EQ(finish_node_task_->GetState(), common::Task::NEW);
CHECK_EQ(when_done_task_->GetState(), common::Task::NEW);
CHECK_EQ(constraints_.size(), 0) << "WhenDone() was not called";
CHECK_EQ(pending_computations_.size(), 0);
CHECK_EQ(submap_queued_work_items_.size(), 0);
CHECK_EQ(num_started_nodes_, num_finished_nodes_);
CHECK(when_done_ == nullptr);
}
@ -77,94 +80,101 @@ void ConstraintBuilder2D::MaybeAddConstraint(
options_.max_constraint_distance()) {
return;
}
if (sampler_.Pulse()) {
if (!sampler_.Pulse()) return;
common::MutexLocker locker(&mutex_);
if (when_done_) {
LOG(WARNING)
<< "MaybeAddConstraint was called while WhenDone was scheduled.";
}
constraints_.emplace_back();
kQueueLengthMetric->Set(constraints_.size());
auto* const constraint = &constraints_.back();
++pending_computations_[current_computation_];
const int current_computation = current_computation_;
ScheduleSubmapScanMatcherConstructionAndQueueWorkItem(
submap_id, submap->grid(), [=]() EXCLUDES(mutex_) {
ComputeConstraint(submap_id, submap, node_id,
false, /* match_full_submap */
constant_data, initial_relative_pose, constraint);
FinishComputation(current_computation);
const auto* scan_matcher =
DispatchScanMatcherConstruction(submap_id, submap->grid());
auto constraint_task = common::make_unique<common::Task>();
constraint_task->SetWorkItem([=]() EXCLUDES(mutex_) {
ComputeConstraint(submap_id, submap, node_id, false, /* match_full_submap */
constant_data, initial_relative_pose, *scan_matcher,
constraint);
});
}
constraint_task->AddDependency(scan_matcher->creation_task_handle);
auto constraint_task_handle =
thread_pool_->Schedule(std::move(constraint_task));
finish_node_task_->AddDependency(constraint_task_handle);
}
void ConstraintBuilder2D::MaybeAddGlobalConstraint(
const SubmapId& submap_id, const Submap2D* const submap,
const NodeId& node_id, const TrajectoryNode::Data* const constant_data) {
common::MutexLocker locker(&mutex_);
if (when_done_) {
LOG(WARNING)
<< "MaybeAddGlobalConstraint was called while WhenDone was scheduled.";
}
constraints_.emplace_back();
kQueueLengthMetric->Set(constraints_.size());
auto* const constraint = &constraints_.back();
++pending_computations_[current_computation_];
const int current_computation = current_computation_;
ScheduleSubmapScanMatcherConstructionAndQueueWorkItem(
submap_id, submap->grid(), [=]() EXCLUDES(mutex_) {
ComputeConstraint(
submap_id, submap, node_id, true, /* match_full_submap */
constant_data, transform::Rigid2d::Identity(), constraint);
FinishComputation(current_computation);
const auto* scan_matcher =
DispatchScanMatcherConstruction(submap_id, submap->grid());
auto constraint_task = common::make_unique<common::Task>();
constraint_task->SetWorkItem([=]() EXCLUDES(mutex_) {
ComputeConstraint(submap_id, submap, node_id, true, /* match_full_submap */
constant_data, transform::Rigid2d::Identity(),
*scan_matcher, constraint);
});
constraint_task->AddDependency(scan_matcher->creation_task_handle);
auto constraint_task_handle =
thread_pool_->Schedule(std::move(constraint_task));
finish_node_task_->AddDependency(constraint_task_handle);
}
void ConstraintBuilder2D::NotifyEndOfNode() {
common::MutexLocker locker(&mutex_);
++current_computation_;
CHECK(finish_node_task_ != nullptr);
finish_node_task_->SetWorkItem([this] {
common::MutexLocker locker(&mutex_);
++num_finished_nodes_;
});
auto finish_node_task_handle =
thread_pool_->Schedule(std::move(finish_node_task_));
finish_node_task_ = common::make_unique<common::Task>();
when_done_task_->AddDependency(finish_node_task_handle);
++num_started_nodes_;
}
void ConstraintBuilder2D::WhenDone(
const std::function<void(const ConstraintBuilder2D::Result&)>& callback) {
common::MutexLocker locker(&mutex_);
CHECK(when_done_ == nullptr);
// TODO(gaschler): Consider using just std::function, it can also be empty.
when_done_ =
common::make_unique<std::function<void(const Result&)>>(callback);
++pending_computations_[current_computation_];
const int current_computation = current_computation_;
thread_pool_->Schedule(
[this, current_computation] { FinishComputation(current_computation); });
}
void ConstraintBuilder2D::ScheduleSubmapScanMatcherConstructionAndQueueWorkItem(
const SubmapId& submap_id, const Grid2D* const grid,
const std::function<void()>& work_item) {
if (submap_scan_matchers_[submap_id].fast_correlative_scan_matcher !=
nullptr) {
thread_pool_->Schedule(work_item);
} else {
submap_queued_work_items_[submap_id].push_back(work_item);
if (submap_queued_work_items_[submap_id].size() == 1) {
thread_pool_->Schedule(
[=]() { ConstructSubmapScanMatcher(submap_id, grid); });
}
}
}
void ConstraintBuilder2D::ConstructSubmapScanMatcher(const SubmapId& submap_id,
const Grid2D* const grid) {
auto submap_scan_matcher =
common::make_unique<scan_matching::FastCorrelativeScanMatcher2D>(
*grid, options_.fast_correlative_scan_matcher_options());
common::MutexLocker locker(&mutex_);
submap_scan_matchers_[submap_id] = {grid, std::move(submap_scan_matcher)};
for (const std::function<void()>& work_item :
submap_queued_work_items_[submap_id]) {
thread_pool_->Schedule(work_item);
}
submap_queued_work_items_.erase(submap_id);
CHECK(when_done_task_ != nullptr);
when_done_task_->SetWorkItem([this] { RunWhenDoneCallback(); });
thread_pool_->Schedule(std::move(when_done_task_));
when_done_task_ = common::make_unique<common::Task>();
}
const ConstraintBuilder2D::SubmapScanMatcher*
ConstraintBuilder2D::GetSubmapScanMatcher(const SubmapId& submap_id) {
common::MutexLocker locker(&mutex_);
const SubmapScanMatcher* submap_scan_matcher =
&submap_scan_matchers_[submap_id];
CHECK(submap_scan_matcher->fast_correlative_scan_matcher != nullptr);
return submap_scan_matcher;
ConstraintBuilder2D::DispatchScanMatcherConstruction(const SubmapId& submap_id,
const Grid2D* const grid) {
if (submap_scan_matchers_.count(submap_id) != 0) {
return &submap_scan_matchers_.at(submap_id);
}
auto& submap_scan_matcher = submap_scan_matchers_[submap_id];
submap_scan_matcher.grid = grid;
auto& scan_matcher_options = options_.fast_correlative_scan_matcher_options();
auto scan_matcher_task = common::make_unique<common::Task>();
scan_matcher_task->SetWorkItem(
[&submap_scan_matcher, &scan_matcher_options]() {
submap_scan_matcher.fast_correlative_scan_matcher =
common::make_unique<scan_matching::FastCorrelativeScanMatcher2D>(
*submap_scan_matcher.grid, scan_matcher_options);
});
submap_scan_matcher.creation_task_handle =
thread_pool_->Schedule(std::move(scan_matcher_task));
return &submap_scan_matchers_.at(submap_id);
}
void ConstraintBuilder2D::ComputeConstraint(
@ -172,11 +182,10 @@ void ConstraintBuilder2D::ComputeConstraint(
const NodeId& node_id, bool match_full_submap,
const TrajectoryNode::Data* const constant_data,
const transform::Rigid2d& initial_relative_pose,
const SubmapScanMatcher& submap_scan_matcher,
std::unique_ptr<ConstraintBuilder2D::Constraint>* constraint) {
const transform::Rigid2d initial_pose =
ComputeSubmapPose(*submap) * initial_relative_pose;
const SubmapScanMatcher* const submap_scan_matcher =
GetSubmapScanMatcher(submap_id);
// The 'constraint_transform' (submap i <- node j) is computed from:
// - a 'filtered_gravity_aligned_point_cloud' in node j,
@ -192,7 +201,7 @@ void ConstraintBuilder2D::ComputeConstraint(
// 3. Refine.
if (match_full_submap) {
kGlobalConstraintsSearchedMetric->Increment();
if (submap_scan_matcher->fast_correlative_scan_matcher->MatchFullSubmap(
if (submap_scan_matcher.fast_correlative_scan_matcher->MatchFullSubmap(
constant_data->filtered_gravity_aligned_point_cloud,
options_.global_localization_min_score(), &score, &pose_estimate)) {
CHECK_GT(score, options_.global_localization_min_score());
@ -205,7 +214,7 @@ void ConstraintBuilder2D::ComputeConstraint(
}
} else {
kConstraintsSearchedMetric->Increment();
if (submap_scan_matcher->fast_correlative_scan_matcher->Match(
if (submap_scan_matcher.fast_correlative_scan_matcher->Match(
initial_pose, constant_data->filtered_gravity_aligned_point_cloud,
options_.min_score(), &score, &pose_estimate)) {
// We've reported a successful local match.
@ -227,7 +236,7 @@ void ConstraintBuilder2D::ComputeConstraint(
ceres::Solver::Summary unused_summary;
ceres_scan_matcher_.Match(pose_estimate.translation(), pose_estimate,
constant_data->filtered_gravity_aligned_point_cloud,
*submap_scan_matcher->grid, &pose_estimate,
*submap_scan_matcher.grid, &pose_estimate,
&unused_summary);
const transform::Rigid2d constraint_transform =
@ -258,22 +267,16 @@ void ConstraintBuilder2D::ComputeConstraint(
}
}
void ConstraintBuilder2D::FinishComputation(const int computation_index) {
void ConstraintBuilder2D::RunWhenDoneCallback() {
Result result;
std::unique_ptr<std::function<void(const Result&)>> callback;
{
common::MutexLocker locker(&mutex_);
if (--pending_computations_[computation_index] == 0) {
pending_computations_.erase(computation_index);
}
if (pending_computations_.empty()) {
CHECK_EQ(submap_queued_work_items_.size(), 0);
if (when_done_ != nullptr) {
CHECK(when_done_ != nullptr);
for (const std::unique_ptr<Constraint>& constraint : constraints_) {
if (constraint != nullptr) {
if (constraint == nullptr) continue;
result.push_back(*constraint);
}
}
if (options_.log_matches()) {
LOG(INFO) << constraints_.size() << " computations resulted in "
<< result.size() << " additional constraints.";
@ -282,26 +285,22 @@ void ConstraintBuilder2D::FinishComputation(const int computation_index) {
constraints_.clear();
callback = std::move(when_done_);
when_done_.reset();
}
}
kQueueLengthMetric->Set(constraints_.size());
}
if (callback != nullptr) {
(*callback)(result);
}
}
int ConstraintBuilder2D::GetNumFinishedNodes() {
common::MutexLocker locker(&mutex_);
if (pending_computations_.empty()) {
return current_computation_;
}
return pending_computations_.begin()->first;
return num_finished_nodes_;
}
void ConstraintBuilder2D::DeleteScanMatcher(const SubmapId& submap_id) {
common::MutexLocker locker(&mutex_);
CHECK(pending_computations_.empty());
if (when_done_) {
LOG(WARNING)
<< "DeleteScanMatcher was called while WhenDone was scheduled.";
}
submap_scan_matchers_.erase(submap_id);
}

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@ -29,6 +29,7 @@
#include "cartographer/common/histogram.h"
#include "cartographer/common/math.h"
#include "cartographer/common/mutex.h"
#include "cartographer/common/task.h"
#include "cartographer/common/thread_pool.h"
#include "cartographer/mapping/2d/submap_2d.h"
#include "cartographer/mapping/internal/2d/scan_matching/ceres_scan_matcher_2d.h"
@ -49,10 +50,10 @@ transform::Rigid2d ComputeSubmapPose(const Submap2D& submap);
// Asynchronously computes constraints.
//
// Intermingle an arbitrary number of calls to MaybeAddConstraint() or
// MaybeAddGlobalConstraint, then call WhenDone(). After all computations are
// done the 'callback' will be called with the result and another
// MaybeAdd(Global)Constraint()/WhenDone() cycle can follow.
// Intermingle an arbitrary number of calls to 'MaybeAddConstraint',
// 'MaybeAddGlobalConstraint', and 'NotifyEndOfNode', then call 'WhenDone' once.
// After all computations are done the 'callback' will be called with the result
// and another MaybeAdd(Global)Constraint()/WhenDone() cycle can follow.
//
// This class is thread-safe.
class ConstraintBuilder2D {
@ -92,7 +93,8 @@ class ConstraintBuilder2D {
void NotifyEndOfNode();
// Registers the 'callback' to be called with the results, after all
// computations triggered by MaybeAddConstraint() have finished.
// computations triggered by 'MaybeAdd*Constraint' have finished.
// 'callback' is executed in the 'ThreadPool'.
void WhenDone(const std::function<void(const Result&)>& callback);
// Returns the number of consecutive finished nodes.
@ -108,21 +110,13 @@ class ConstraintBuilder2D {
const Grid2D* grid;
std::unique_ptr<scan_matching::FastCorrelativeScanMatcher2D>
fast_correlative_scan_matcher;
std::weak_ptr<common::Task> creation_task_handle;
};
// Either schedules the 'work_item', or if needed, schedules the scan matcher
// construction and queues the 'work_item'.
void ScheduleSubmapScanMatcherConstructionAndQueueWorkItem(
const SubmapId& submap_id, const Grid2D* grid,
const std::function<void()>& work_item) REQUIRES(mutex_);
// Constructs the scan matcher for a 'submap', then schedules its work items.
void ConstructSubmapScanMatcher(const SubmapId& submap_id, const Grid2D* grid)
EXCLUDES(mutex_);
// Returns the scan matcher for a submap, which has to exist.
const SubmapScanMatcher* GetSubmapScanMatcher(const SubmapId& submap_id)
EXCLUDES(mutex_);
// The returned 'grid' and 'fast_correlative_scan_matcher' must only be
// accessed after 'creation_task_handle' has completed.
const SubmapScanMatcher* DispatchScanMatcherConstruction(
const SubmapId& submap_id, const Grid2D* grid) REQUIRES(mutex_);
// Runs in a background thread and does computations for an additional
// constraint, assuming 'submap' and 'compressed_point_cloud' do not change
@ -131,12 +125,11 @@ class ConstraintBuilder2D {
const NodeId& node_id, bool match_full_submap,
const TrajectoryNode::Data* const constant_data,
const transform::Rigid2d& initial_relative_pose,
const SubmapScanMatcher& submap_scan_matcher,
std::unique_ptr<Constraint>* constraint)
EXCLUDES(mutex_);
// Decrements the 'pending_computations_' count. If all computations are done,
// runs the 'when_done_' callback and resets the state.
void FinishComputation(int computation_index) EXCLUDES(mutex_);
void RunWhenDoneCallback() EXCLUDES(mutex_);
const constraints::proto::ConstraintBuilderOptions options_;
common::ThreadPoolInterface* thread_pool_;
@ -146,28 +139,27 @@ class ConstraintBuilder2D {
std::unique_ptr<std::function<void(const Result&)>> when_done_
GUARDED_BY(mutex_);
// Index of the node in reaction to which computations are currently
// added. This is always the highest node index seen so far, even when older
// TODO(gaschler): Use atomics instead of mutex to access these counters.
// Number of the node in reaction to which computations are currently
// added. This is always the number of nodes seen so far, even when older
// nodes are matched against a new submap.
int current_computation_ GUARDED_BY(mutex_) = 0;
int num_started_nodes_ GUARDED_BY(mutex_) = 0;
// For each added node, maps to the number of pending computations that were
// added for it.
std::map<int, int> pending_computations_ GUARDED_BY(mutex_);
int num_finished_nodes_ GUARDED_BY(mutex_) = 0;
std::unique_ptr<common::Task> finish_node_task_ GUARDED_BY(mutex_);
std::unique_ptr<common::Task> when_done_task_ GUARDED_BY(mutex_);
// Constraints currently being computed in the background. A deque is used to
// keep pointers valid when adding more entries.
// keep pointers valid when adding more entries. Constraint search results
// with below-threshold scores are also 'nullptr'.
std::deque<std::unique_ptr<Constraint>> constraints_ GUARDED_BY(mutex_);
// Map of already constructed scan matchers by 'submap_id'.
// Map of dispatched or constructed scan matchers by 'submap_id'.
std::map<SubmapId, SubmapScanMatcher> submap_scan_matchers_
GUARDED_BY(mutex_);
// Map by 'submap_id' of scan matchers under construction, and the work
// to do once construction is done.
std::map<SubmapId, std::vector<std::function<void()>>>
submap_queued_work_items_ GUARDED_BY(mutex_);
common::FixedRatioSampler sampler_;
scan_matching::CeresScanMatcher2D ceres_scan_matcher_;