Add mocks for blockstore integration tests: timerfd, ring_loop_mock_t and disk_mock_t

src/util/ringloop.cpp

@@ -8,6 +8,7 @@
 
 #include <sys/eventfd.h>
 
+#include "malloc_or_die.h"
 #include "ringloop.h"
 
 ring_loop_t::ring_loop_t(int qd, bool multithreaded, bool sqe128)
@@ -228,3 +229,230 @@ int ring_loop_t::register_eventfd()
     loop();
     return ring_eventfd;
 }
+
+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(ring_loop_mock_t *loop, size_t size)
+{
+    this->loop = loop;
+    this->size = size;
+    this->data = (uint8_t*)malloc_or_die(size);
+}
+
+disk_mock_t::~disk_mock_t()
+{
+    free(data);
+}
+
+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++)
+        {
+            size_t cur = (off + v[i].iov_len > size ? size-off : v[i].iov_len);
+            if (trace)
+                printf("read %zu+%zu to %jx\n", off, cur, (uint64_t)v[i].iov_base);
+            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)
+    {
+        // Simple "immediate" mode. We should also implement "buffered" mode
+        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("write %zu+%zu from %jx\n", off, cur, (uint64_t)v[i].iov_base);
+            memcpy(data + off, v[i].iov_base, cur);
+            off += v[i].iov_len;
+        }
+        userdata->res = off - sqe->off;
+    }
+    else if (sqe->opcode == IORING_OP_FSYNC)
+    {
+        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
+    loop->mark_completed(userdata);
+    return true;
+}