Files
scylladb/test/lib/reader_lifecycle_policy.hh

115 lines
4.9 KiB
C++

/*
* Copyright (C) 2020-present ScyllaDB
*/
/*
* SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
*/
#pragma once
#include "utils/assert.hh"
#include "readers/multishard.hh"
#include <seastar/core/gate.hh>
class test_reader_lifecycle_policy
: public reader_lifecycle_policy
, public enable_shared_from_this<test_reader_lifecycle_policy> {
public:
using reader_factory_function = std::function<mutation_reader(
schema_ptr,
reader_permit,
const dht::partition_range&,
const query::partition_slice&,
tracing::trace_state_ptr,
mutation_reader::forwarding)>;
class semaphore_factory {
public:
virtual ~semaphore_factory() = default;
virtual lw_shared_ptr<reader_concurrency_semaphore> create(sstring name) {
return make_lw_shared<reader_concurrency_semaphore>(reader_concurrency_semaphore::no_limits{}, std::move(name), reader_concurrency_semaphore::register_metrics::no);
}
virtual future<> stop(reader_concurrency_semaphore& semaphore) {
return semaphore.stop();
}
};
private:
struct reader_context {
lw_shared_ptr<reader_concurrency_semaphore> semaphore;
lw_shared_ptr<const dht::partition_range> range;
std::optional<const query::partition_slice> slice;
reader_context() = default;
reader_context(dht::partition_range range, query::partition_slice slice)
: range(make_lw_shared<const dht::partition_range>(std::move(range))), slice(std::move(slice)) {
}
};
reader_factory_function _reader_factory_function;
std::unique_ptr<semaphore_factory> _semaphore_factory;
std::vector<foreign_ptr<std::unique_ptr<reader_context>>> _contexts;
std::vector<future<>> _destroy_futures;
public:
explicit test_reader_lifecycle_policy(reader_factory_function reader_factory, std::unique_ptr<semaphore_factory> semaphore_factory_object = std::make_unique<semaphore_factory>())
: _reader_factory_function(std::move(reader_factory))
, _semaphore_factory(std::move(semaphore_factory_object))
, _contexts(smp::count) {
}
virtual mutation_reader create_reader(
schema_ptr schema,
reader_permit permit,
const dht::partition_range& range,
const query::partition_slice& slice,
tracing::trace_state_ptr trace_state,
mutation_reader::forwarding fwd_mr) override {
const auto shard = this_shard_id();
if (_contexts[shard]) {
_contexts[shard]->range = make_lw_shared<const dht::partition_range>(range);
_contexts[shard]->slice.emplace(slice);
} else {
_contexts[shard] = make_foreign(std::make_unique<reader_context>(range, slice));
}
return _reader_factory_function(std::move(schema), std::move(permit), *_contexts[shard]->range, *_contexts[shard]->slice, std::move(trace_state), fwd_mr);
}
virtual const dht::partition_range* get_read_range() const override {
const auto shard = this_shard_id();
SCYLLA_ASSERT(_contexts[shard]);
return _contexts[shard]->range.get();
}
void update_read_range(lw_shared_ptr<const dht::partition_range> range) override {
const auto shard = this_shard_id();
SCYLLA_ASSERT(_contexts[shard]);
_contexts[shard]->range = std::move(range);
}
virtual future<> destroy_reader(stopped_reader reader) noexcept override {
auto& ctx = _contexts[this_shard_id()];
auto reader_opt = ctx->semaphore->unregister_inactive_read(std::move(reader.handle));
auto ret = reader_opt ? reader_opt->close() : make_ready_future<>();
return ret.finally([this, &ctx] {
return _semaphore_factory->stop(*ctx->semaphore).finally([&ctx] {
ctx.release();
});
});
}
virtual reader_concurrency_semaphore& semaphore() override {
const auto shard = this_shard_id();
if (!_contexts[shard]) {
_contexts[shard] = make_foreign(std::make_unique<reader_context>());
} else if (_contexts[shard]->semaphore) {
return *_contexts[shard]->semaphore;
}
// To support multiple reader life-cycle instances alive at the same
// time, incorporate `this` into the name, to make their names unique.
auto name = format("tests::reader_lifecycle_policy@{}@shard_id={}", fmt::ptr(this), shard);
_contexts[shard]->semaphore = _semaphore_factory->create(std::move(name));
return *_contexts[shard]->semaphore;
}
virtual future<reader_permit> obtain_reader_permit(schema_ptr schema, const char* const description, db::timeout_clock::time_point timeout, tracing::trace_state_ptr trace_ptr) override {
return semaphore().obtain_permit(schema, description, 128 * 1024, timeout, std::move(trace_ptr));
}
};