Files
tromcho.net/src/test/ringloop_mock.cpp
T

399 lines
10 KiB
C++

// Copyright (c) Vitaliy Filippov, 2019+
// License: VNPL-1.1 or GNU GPL-2.0+ (see README.md for details)
#include <random>
#include "ringloop_mock.h"
#include "malloc_or_die.h"
ring_loop_mock_t::ring_loop_mock_t(int qd, std::function<void(io_uring_sqe *)> submit_cb)
{
this->submit_cb = std::move(submit_cb);
sqes.resize(qd);
ring_datas.resize(qd);
free_ring_datas.reserve(qd);
submit_ring_datas.reserve(qd);
completed_ring_datas.reserve(qd);
for (size_t i = 0; i < ring_datas.size(); i++)
{
free_ring_datas.push_back(ring_datas.data() + i);
}
in_loop = false;
}
void ring_loop_mock_t::register_consumer(ring_consumer_t *consumer)
{
unregister_consumer(consumer);
consumers.push_back(consumer);
}
void ring_loop_mock_t::unregister_consumer(ring_consumer_t *consumer)
{
for (int i = 0; i < consumers.size(); i++)
{
if (consumers[i] == consumer)
{
consumers.erase(consumers.begin()+i, consumers.begin()+i+1);
break;
}
}
}
void ring_loop_mock_t::wakeup()
{
loop_again = true;
}
void ring_loop_mock_t::set_immediate(const std::function<void()> & cb)
{
immediate_queue.push_back(cb);
wakeup();
}
unsigned ring_loop_mock_t::space_left()
{
return free_ring_datas.size();
}
bool ring_loop_mock_t::has_work()
{
return loop_again;
}
bool ring_loop_mock_t::has_sendmsg_zc()
{
return false;
}
int ring_loop_mock_t::register_eventfd()
{
return -1;
}
io_uring_sqe* ring_loop_mock_t::get_sqe()
{
if (free_ring_datas.size() == 0)
{
return NULL;
}
ring_data_t *d = free_ring_datas.back();
free_ring_datas.pop_back();
submit_ring_datas.push_back(d);
io_uring_sqe *sqe = &sqes[d - ring_datas.data()];
*sqe = { 0 };
io_uring_sqe_set_data(sqe, d);
return sqe;
}
int ring_loop_mock_t::submit()
{
for (size_t i = 0; i < submit_ring_datas.size(); i++)
{
submit_cb(&sqes[submit_ring_datas[i] - ring_datas.data()]);
}
submit_ring_datas.clear();
return 0;
}
int ring_loop_mock_t::wait()
{
return 0;
}
unsigned ring_loop_mock_t::save()
{
return submit_ring_datas.size();
}
void ring_loop_mock_t::restore(unsigned sqe_tail)
{
while (submit_ring_datas.size() > sqe_tail)
{
free_ring_datas.push_back(submit_ring_datas.back());
submit_ring_datas.pop_back();
}
}
void ring_loop_mock_t::loop()
{
if (in_loop)
{
return;
}
in_loop = true;
submit();
while (completed_ring_datas.size())
{
ring_data_t *d = completed_ring_datas.back();
completed_ring_datas.pop_back();
if (d->callback)
{
struct ring_data_t dl;
dl.iov = d->iov;
dl.res = d->res;
dl.more = dl.prev = false;
dl.callback.swap(d->callback);
free_ring_datas.push_back(d);
dl.callback(&dl);
}
else
{
fprintf(stderr, "Warning: empty callback in SQE\n");
free_ring_datas.push_back(d);
}
}
do
{
loop_again = false;
for (int i = 0; i < consumers.size(); i++)
{
consumers[i]->loop();
if (immediate_queue.size())
{
immediate_queue2.swap(immediate_queue);
for (auto & cb: immediate_queue2)
cb();
immediate_queue2.clear();
}
}
} while (loop_again);
in_loop = false;
}
void ring_loop_mock_t::mark_completed(ring_data_t *data)
{
completed_ring_datas.push_back(data);
wakeup();
}
disk_mock_t::disk_mock_t(size_t size, bool buffered)
{
this->size = size;
this->data = (uint8_t*)malloc_or_die(size);
this->buffered = buffered;
memset(this->data, 0, size);
}
disk_mock_t::~disk_mock_t()
{
discard_buffers(true, 0);
free(data);
}
void disk_mock_t::erase_buffers(uint64_t begin, uint64_t end)
{
for (auto it = buffers.upper_bound(begin); it != buffers.end(); )
{
const uint64_t bs = it->first - it->second.iov_len;
const uint64_t be = it->first;
if (bs >= end)
{
break;
}
if (bs >= begin && be <= end)
{
// Remove the whole buffer
buffers.erase(it++);
}
else if (bs < begin && be > end)
{
// Cut beginning & end & stop
uint8_t *ce = (uint8_t*)malloc_or_die(be-end);
memcpy(ce, it->second.iov_base + (end-bs), be-end);
uint8_t *cs = (uint8_t*)realloc(it->second.iov_base, begin-bs);
if (!cs)
throw std::bad_alloc();
buffers[begin] = (iovec){ .iov_base = cs, .iov_len = begin-bs };
buffers[be] = (iovec){ .iov_base = ce, .iov_len = be-end };
break;
}
else if (bs < begin)
{
// Cut beginning
uint8_t *cs = (uint8_t*)realloc(it->second.iov_base, begin-bs);
if (!cs)
throw std::bad_alloc();
buffers[begin] = (iovec){ .iov_base = cs, .iov_len = begin-bs };
buffers.erase(it++);
}
else
{
// Cut end & stop
assert(be > end);
uint8_t *ce = (uint8_t*)malloc_or_die(be-end);
memcpy(ce, it->second.iov_base + (end-bs), be-end);
buffers[be] = (iovec){ .iov_base = ce, .iov_len = be-end };
buffers.erase(it);
break;
}
}
}
void disk_mock_t::clear(size_t offset, size_t len)
{
if (offset < size)
{
memset(data+offset, 0, len < size-offset ? len : size-offset);
}
}
void disk_mock_t::discard_buffers(bool all, uint32_t seed)
{
if (all)
{
if (trace)
printf("disk: discard all buffers (%zu)\n", buffers.size());
for (auto & b: buffers)
free(b.second.iov_base);
buffers.clear();
}
else
{
if (trace)
printf("disk: discard random buffers seed=%u\n", seed);
std::mt19937 rnd(seed);
for (auto it = buffers.begin(); it != buffers.end(); )
{
if (rnd() < 0x80000000)
{
free(it->second.iov_base);
buffers.erase(it++);
}
else
it++;
}
}
}
ssize_t disk_mock_t::copy_from_sqe(io_uring_sqe *sqe, uint8_t *to, uint64_t base_offset)
{
size_t off = sqe->off;
iovec *v = (iovec*)sqe->addr;
size_t n = sqe->len;
for (size_t i = 0; i < n; i++)
{
if (off >= size)
{
off = sqe->off - EINVAL; // :D
break;
}
size_t cur = (off + v[i].iov_len > size ? size-off : v[i].iov_len);
if (trace)
printf("disk: write %zu+%zu from %jx\n", off, cur, (uint64_t)v[i].iov_base);
memcpy(to + off - base_offset, v[i].iov_base, cur);
off += v[i].iov_len;
}
return off - sqe->off;
}
void disk_mock_t::read_item(uint8_t *to, uint64_t offset, uint64_t len)
{
uint64_t last = offset;
for (auto it = buffers.upper_bound(offset); it != buffers.end(); it++)
{
const uint64_t bs = it->first - it->second.iov_len;
const uint64_t be = it->first;
if (bs >= offset+len)
{
break;
}
if (last < bs)
{
// Fill the gap between buffers
memcpy(to+last-offset, data+last, bs-last);
last = bs;
}
if (last < offset)
{
last = offset;
}
uint64_t cur_end = be < offset+len ? be : offset+len;
memcpy(to+last-offset, it->second.iov_base+last-bs, cur_end-last);
last = be;
}
if (last < offset+len)
{
// Fill the gap in the end
memcpy(to+last-offset, data+last, offset+len-last);
}
}
bool disk_mock_t::submit(io_uring_sqe *sqe)
{
ring_data_t *userdata = (ring_data_t*)sqe->user_data;
if (sqe->opcode == IORING_OP_READV)
{
size_t off = sqe->off;
iovec *v = (iovec*)sqe->addr;
size_t n = sqe->len;
for (size_t i = 0; i < n; i++)
{
if (off < size)
{
size_t cur = (off + v[i].iov_len > size ? size-off : v[i].iov_len);
if (trace)
printf("disk: read %zu+%zu to %jx\n", off, cur, (uint64_t)v[i].iov_base);
if (buffers.size())
read_item((uint8_t*)v[i].iov_base, off, cur);
else
memcpy(v[i].iov_base, data + off, cur);
}
off += v[i].iov_len;
}
userdata->res = off - sqe->off;
}
else if (sqe->opcode == IORING_OP_WRITEV)
{
uint64_t end = 0;
if (buffered)
{
// Remove overwritten parts of buffers
end = sqe->off;
for (uint32_t i = 0; i < sqe->len; i++)
{
end += ((iovec*)sqe->addr)[i].iov_len;
}
erase_buffers(sqe->off, end);
}
if (!buffered || (sqe->rw_flags & RWF_DSYNC))
{
// Simple "immediate" mode
userdata->res = copy_from_sqe(sqe, data, 0);
}
else
{
// Buffered mode
uint8_t *buf = (uint8_t*)malloc_or_die(end - sqe->off);
userdata->res = copy_from_sqe(sqe, buf, sqe->off);
if (userdata->res == -EINVAL)
free(buf);
else
buffers[end] = (iovec){ .iov_base = buf, .iov_len = end-sqe->off };
}
}
else if (sqe->opcode == IORING_OP_FSYNC)
{
if (trace)
printf("disk: fsync\n");
if (buffers.size())
{
for (auto & b: buffers)
{
memcpy(data + b.first - b.second.iov_len, b.second.iov_base, b.second.iov_len);
free(b.second.iov_base);
}
buffers.clear();
}
userdata->res = 0;
}
else
{
return false;
}
// Execution variability should also be introduced:
// 1) reads submitted in parallel to writes (not after completing the write) should return old or new data randomly
// 2) parallel operation completions should be delivered in random order
// 3) when fsync is enabled, write cache should be sometimes lost during a simulated power outage
return true;
}