Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

coroutine: experimental: generator: implement move and swap #2354

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

coroutine: experimental: generator: implement move and swap #2354

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
52 changes: 48 additions & 4 deletions include/seastar/coroutine/generator.hh
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -94,7 +94,6 @@ public:

generator_type get_return_object() noexcept;
void set_generator(generator_type* g) noexcept {
assert(!_generator);
_generator = g;
}

Expand Down Expand Up @@ -190,7 +189,6 @@ public:

auto get_return_object() noexcept -> generator_type;
void set_generator(generator_type* g) noexcept {
assert(!_generator);
_generator = g;
}

Expand Down Expand Up @@ -335,13 +333,27 @@ public:
generator(const generator&) = delete;
generator(generator&& other) noexcept
: _coro{std::exchange(other._coro, {})}
, _buffer_capacity{other._buffer_capacity} {}
, _promise(std::exchange(other._promise, nullptr))
, _values(std::move(other._values))
, _buffer_capacity{other._buffer_capacity}
, _exception(std::exchange(other._exception, nullptr)) {
if (_promise) {
_promise->set_generator(this);
}
}
generator& operator=(generator&& other) noexcept {
if (std::addressof(other) != this) {
auto old_coro = std::exchange(_coro, std::exchange(other._coro, {}));
if (old_coro) {
old_coro.destroy();
}
_promise = std::exchange(other._promise, nullptr);
if (_promise) {
_promise->set_generator(this);
}
_values = std::move(other._values);
const_cast<size_t&>(_buffer_capacity) = other._buffer_capacity;
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Maybe:

Suggested change
const_cast<size_t&>(_buffer_capacity) = other._buffer_capacity;
const_cast<size_t&>(_buffer_capacity) = std::exchange(other._buffer_capacity, 0);

_exception = std::exchange(other._exception, nullptr);
}
return *this;
}
Expand All @@ -353,6 +365,16 @@ public:

void swap(generator& other) noexcept {
std::swap(_coro, other._coro);
std::swap(_promise, other._promise);
if (_promise) {
_promise->set_generator(this);
}
if (other._promise) {
other._promise->set_generator(&other);
}
std::swap(_values, other._values);
std::swap(const_cast<size_t&>(_buffer_capacity), const_cast<size_t&>(other._buffer_capacity));
std::swap(_exception, other._exception);
}

internal::next_awaiter<T, generator> operator()() noexcept {
Expand Down Expand Up @@ -425,13 +447,26 @@ public:
}
generator(const generator&) = delete;
generator(generator&& other) noexcept
: _coro{std::exchange(other._coro, {})} {}
: _coro{std::exchange(other._coro, {})}
, _promise(std::exchange(other._promise, nullptr))
, _maybe_value(std::exchange(other._maybe_value, std::nullopt))
, _exception(std::exchange(other._exception, nullptr)) {
if (_promise) {
_promise->set_generator(this);
}
}
generator& operator=(generator&& other) noexcept {
if (std::addressof(other) != this) {
auto old_coro = std::exchange(_coro, std::exchange(other._coro, {}));
if (old_coro) {
old_coro.destroy();
}
_promise = std::exchange(other._promise, nullptr);
if (_promise) {
_promise->set_generator(this);
}
_maybe_value = std::exchange(other._maybe_value, std::nullopt);
_exception = std::exchange(other._exception, nullptr);
}
return *this;
}
Expand All @@ -443,6 +478,15 @@ public:

void swap(generator& other) noexcept {
std::swap(_coro, other._coro);
std::swap(_promise, other._promise);
if (_promise) {
_promise->set_generator(this);
}
if (other._promise) {
other._promise->set_generator(&other);
}
std::swap(_maybe_value, other._maybe_value);
std::swap(_exception, other._exception);
}

internal::next_awaiter<T, generator> operator()() noexcept {
Expand Down
94 changes: 90 additions & 4 deletions tests/unit/coroutines_test.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -741,6 +741,14 @@ SEASTAR_TEST_CASE(test_as_future_preemption) {
BOOST_REQUIRE_THROW(f0.get(), std::runtime_error);
}

std::vector<int> gen_expected_fibs(unsigned count) {
std::vector<int> expected_fibs = {0, 1};
for (unsigned i = 2; i < count; ++i) {
expected_fibs.emplace_back(expected_fibs[i-2] + expected_fibs[i-1]);
}
return expected_fibs;
}

template<template<typename> class Container>
coroutine::experimental::generator<int, Container>
fibonacci_sequence(coroutine::experimental::buffer_size_t size, unsigned count) {
Expand All @@ -755,10 +763,8 @@ fibonacci_sequence(coroutine::experimental::buffer_size_t size, unsigned count)
}

template<template<typename> class Container>
seastar::future<> test_async_generator_drained() {
auto expected_fibs = {0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55};
auto fib = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2},
std::size(expected_fibs));
seastar::future<> test_async_generator_drained(coroutine::experimental::generator<int, Container> fib, unsigned count) {
auto expected_fibs = gen_expected_fibs(count);
for (auto expected_fib : expected_fibs) {
auto actual_fib = co_await fib();
BOOST_REQUIRE(actual_fib.has_value());
Expand All @@ -768,6 +774,37 @@ seastar::future<> test_async_generator_drained() {
BOOST_REQUIRE(!sentinel.has_value());
}

template<template<typename> class Container>
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The entire new section is missing some verbal explanations about the tests, the expected results and how they are achieved.

seastar::future<> test_async_generator_drained() {
unsigned count = 11;
co_await test_async_generator_drained(fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, count), count);
}

template<template<typename> class Container>
seastar::future<> test_move_async_generator_drained() {
unsigned count = 11;
auto fib0 = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, count);
co_await test_async_generator_drained(std::move(fib0), count);
auto fib1 = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, ++count);
fib0 = std::move(fib1);
co_await test_async_generator_drained(std::move(fib0), count);
fib0 = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, ++count);
fib1 = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, ++count);
fib0 = std::move(fib1);
co_await test_async_generator_drained(std::move(fib0), count);
}

template<template<typename> class Container>
seastar::future<> test_swap_async_generator_drained() {
unsigned count[2] = {11, 17};
auto fib0 = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, count[0]);
auto fib1 = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, count[1]);
std::swap(fib0, fib1);
std::swap(count[0], count[1]);
co_await test_async_generator_drained(std::move(fib0), count[0]);
co_await test_async_generator_drained(std::move(fib1), count[1]);
}

template<typename T>
using buffered_container = circular_buffer<T>;

Expand All @@ -779,6 +816,55 @@ SEASTAR_TEST_CASE(test_async_generator_drained_unbuffered) {
return test_async_generator_drained<std::optional>();
}

SEASTAR_TEST_CASE(test_move_async_generator_drained_buffered) {
return test_move_async_generator_drained<buffered_container>();
}

SEASTAR_TEST_CASE(test_move_async_generator_drained_unbuffered) {
return test_move_async_generator_drained<std::optional>();
}

SEASTAR_TEST_CASE(test_swap_async_generator_drained_buffered) {
return test_swap_async_generator_drained<buffered_container>();
}

SEASTAR_TEST_CASE(test_swap_async_generator_drained_unbuffered) {
return test_swap_async_generator_drained<std::optional>();
}

template<template<typename> class Container>
seastar::future<coroutine::experimental::generator<int, Container>> test_async_generator_drained_incrementally(coroutine::experimental::generator<int, Container> fib, std::optional<int> expected_value) {
auto actual_fib = co_await fib();
if (expected_value) {
BOOST_REQUIRE(actual_fib.has_value());
BOOST_REQUIRE_EQUAL(actual_fib.value(), *expected_value);
} else {
BOOST_REQUIRE(!actual_fib.has_value());
}
co_return fib;
}

template<template<typename> class Container>
seastar::future<> test_async_generator_drained_incrementally() {
unsigned count = 17;
auto expected_fibs = gen_expected_fibs(count);
auto fib = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2}, count);
for (auto it = expected_fibs.begin(); it != expected_fibs.end(); ++it) {
fib = co_await test_async_generator_drained_incrementally(std::move(fib), *it);
}
fib = co_await test_async_generator_drained_incrementally(std::move(fib), std::nullopt);
// once drained generator return std::nullopt
fib = co_await test_async_generator_drained_incrementally(std::move(fib), std::nullopt);
}

SEASTAR_TEST_CASE(test_async_generator_drained_incrementally_buffered) {
return test_async_generator_drained_incrementally<buffered_container>();
}

SEASTAR_TEST_CASE(test_async_generator_drained_incrementally_unbuffered) {
return test_async_generator_drained_incrementally<std::optional>();
}

template<template<typename> class Container>
seastar::future<> test_async_generator_not_drained() {
auto fib = fibonacci_sequence<Container>(coroutine::experimental::buffer_size_t{2},
Expand Down