blob: eb97a98a2d2e93e75eefaa7cb875171a5a4855bf [file] [log] [blame]
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <android-base/logging.h>
#include <condition_variable>
#include <memory>
#include <mutex>
#include <queue>
#include "AsyncIO.h"
void read_func(struct aiocb *aiocbp) {
aiocbp->ret = TEMP_FAILURE_RETRY(pread(aiocbp->aio_fildes,
aiocbp->aio_buf, aiocbp->aio_nbytes, aiocbp->aio_offset));
if (aiocbp->ret == -1) aiocbp->error = errno;
}
void write_func(struct aiocb *aiocbp) {
aiocbp->ret = TEMP_FAILURE_RETRY(pwrite(aiocbp->aio_fildes,
aiocbp->aio_buf, aiocbp->aio_nbytes, aiocbp->aio_offset));
if (aiocbp->ret == -1) aiocbp->error = errno;
}
void splice_read_func(struct aiocb *aiocbp) {
loff_t long_offset = aiocbp->aio_offset;
aiocbp->ret = TEMP_FAILURE_RETRY(splice(aiocbp->aio_fildes,
&long_offset, aiocbp->aio_sink,
NULL, aiocbp->aio_nbytes, 0));
if (aiocbp->ret == -1) aiocbp->error = errno;
}
void splice_write_func(struct aiocb *aiocbp) {
loff_t long_offset = aiocbp->aio_offset;
aiocbp->ret = TEMP_FAILURE_RETRY(splice(aiocbp->aio_fildes, NULL,
aiocbp->aio_sink, &long_offset,
aiocbp->aio_nbytes, 0));
if (aiocbp->ret == -1) aiocbp->error = errno;
}
std::queue<std::unique_ptr<struct aiocb>> queue;
std::mutex queue_lock;
std::condition_variable queue_cond;
std::condition_variable write_cond;
int done = 1;
void splice_write_pool_func(int) {
while(1) {
std::unique_lock<std::mutex> lk(queue_lock);
queue_cond.wait(lk, []{return !queue.empty() || done;});
if (queue.empty() && done) {
return;
}
std::unique_ptr<struct aiocb> aiocbp = std::move(queue.front());
queue.pop();
lk.unlock();
write_cond.notify_one();
splice_write_func(aiocbp.get());
close(aiocbp->aio_fildes);
}
}
void write_pool_func(int) {
while(1) {
std::unique_lock<std::mutex> lk(queue_lock);
queue_cond.wait(lk, []{return !queue.empty() || done;});
if (queue.empty() && done) {
return;
}
std::unique_ptr<struct aiocb> aiocbp = std::move(queue.front());
queue.pop();
lk.unlock();
write_cond.notify_one();
aiocbp->ret = TEMP_FAILURE_RETRY(pwrite(aiocbp->aio_fildes,
aiocbp->aio_pool_buf.get(), aiocbp->aio_nbytes, aiocbp->aio_offset));
if (aiocbp->ret == -1) aiocbp->error = errno;
}
}
constexpr int NUM_THREADS = 1;
constexpr int MAX_QUEUE_SIZE = 10;
std::thread pool[NUM_THREADS];
aiocb::~aiocb() {
CHECK(!thread.joinable());
}
void aio_pool_init(void(f)(int)) {
CHECK(done == 1);
done = 0;
for (int i = 0; i < NUM_THREADS; i++) {
pool[i] = std::thread(f, i);
}
}
void aio_pool_splice_init() {
aio_pool_init(splice_write_pool_func);
}
void aio_pool_write_init() {
aio_pool_init(write_pool_func);
}
void aio_pool_end() {
done = 1;
for (int i = 0; i < NUM_THREADS; i++) {
std::unique_lock<std::mutex> lk(queue_lock);
lk.unlock();
queue_cond.notify_one();
}
for (int i = 0; i < NUM_THREADS; i++) {
pool[i].join();
}
}
// used for both writes and splices depending on which init was used before.
int aio_pool_write(struct aiocb *aiocbp) {
std::unique_lock<std::mutex> lk(queue_lock);
write_cond.wait(lk, []{return queue.size() < MAX_QUEUE_SIZE;});
queue.push(std::unique_ptr<struct aiocb>(aiocbp));
lk.unlock();
queue_cond.notify_one();
return 0;
}
int aio_read(struct aiocb *aiocbp) {
aiocbp->thread = std::thread(read_func, aiocbp);
return 0;
}
int aio_write(struct aiocb *aiocbp) {
aiocbp->thread = std::thread(write_func, aiocbp);
return 0;
}
int aio_splice_read(struct aiocb *aiocbp) {
aiocbp->thread = std::thread(splice_read_func, aiocbp);
return 0;
}
int aio_splice_write(struct aiocb *aiocbp) {
aiocbp->thread = std::thread(splice_write_func, aiocbp);
return 0;
}
int aio_error(const struct aiocb *aiocbp) {
return aiocbp->error;
}
ssize_t aio_return(struct aiocb *aiocbp) {
return aiocbp->ret;
}
int aio_suspend(struct aiocb *aiocbp[], int n,
const struct timespec *) {
for (int i = 0; i < n; i++) {
aiocbp[i]->thread.join();
}
return 0;
}
int aio_cancel(int, struct aiocb *) {
// Not implemented
return -1;
}