* GNU GPL, version 2 or (at your option) any later version.
*/
+#include "qemu/osdep.h"
#include "qemu-common.h"
#include "block/block.h"
#include "qemu/queue.h"
GPollFD pfd;
int deleted;
void *opaque;
+ bool is_external;
QLIST_ENTRY(AioHandler) node;
};
void aio_set_fd_handler(AioContext *ctx,
int fd,
+ bool is_external,
IOHandler *io_read,
IOHandler *io_write,
void *opaque)
node->opaque = opaque;
node->io_read = io_read;
node->io_write = io_write;
+ node->is_external = is_external;
event = event_notifier_get_handle(&ctx->notifier);
WSAEventSelect(node->pfd.fd, event,
void aio_set_event_notifier(AioContext *ctx,
EventNotifier *e,
+ bool is_external,
EventNotifierHandler *io_notify)
{
AioHandler *node;
node->e = e;
node->pfd.fd = (uintptr_t)event_notifier_get_handle(e);
node->pfd.events = G_IO_IN;
+ node->is_external = is_external;
QLIST_INSERT_HEAD(&ctx->aio_handlers, node, node);
g_source_add_poll(&ctx->source, &node->pfd);
{
AioHandler *node;
HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
- bool was_dispatching, progress, have_select_revents, first;
+ bool progress, have_select_revents, first;
int count;
int timeout;
- have_select_revents = aio_prepare(ctx);
- if (have_select_revents) {
- blocking = false;
- }
-
- was_dispatching = ctx->dispatching;
+ aio_context_acquire(ctx);
progress = false;
/* aio_notify can avoid the expensive event_notifier_set if
* everything (file descriptors, bottom halves, timers) will
* be re-evaluated before the next blocking poll(). This is
* already true when aio_poll is called with blocking == false;
- * if blocking == true, it is only true after poll() returns.
- *
- * If we're in a nested event loop, ctx->dispatching might be true.
- * In that case we can restore it just before returning, but we
- * have to clear it now.
+ * if blocking == true, it is only true after poll() returns,
+ * so disable the optimization now.
*/
- aio_set_dispatching(ctx, !blocking);
+ if (blocking) {
+ atomic_add(&ctx->notify_me, 2);
+ }
+
+ have_select_revents = aio_prepare(ctx);
ctx->walking_handlers++;
/* fill fd sets */
count = 0;
QLIST_FOREACH(node, &ctx->aio_handlers, node) {
- if (!node->deleted && node->io_notify) {
+ if (!node->deleted && node->io_notify
+ && aio_node_check(ctx, node->is_external)) {
events[count++] = event_notifier_get_handle(node->e);
}
}
ctx->walking_handlers--;
first = true;
- /* wait until next event */
- while (count > 0) {
+ /* ctx->notifier is always registered. */
+ assert(count > 0);
+
+ /* Multiple iterations, all of them non-blocking except the first,
+ * may be necessary to process all pending events. After the first
+ * WaitForMultipleObjects call ctx->notify_me will be decremented.
+ */
+ do {
HANDLE event;
int ret;
- timeout = blocking
+ timeout = blocking && !have_select_revents
? qemu_timeout_ns_to_ms(aio_compute_timeout(ctx)) : 0;
+ if (timeout) {
+ aio_context_release(ctx);
+ }
ret = WaitForMultipleObjects(count, events, FALSE, timeout);
- aio_set_dispatching(ctx, true);
+ if (blocking) {
+ assert(first);
+ atomic_sub(&ctx->notify_me, 2);
+ }
+ if (timeout) {
+ aio_context_acquire(ctx);
+ }
- if (first && aio_bh_poll(ctx)) {
- progress = true;
+ if (first) {
+ aio_notify_accept(ctx);
+ progress |= aio_bh_poll(ctx);
+ first = false;
}
- first = false;
/* if we have any signaled events, dispatch event */
event = NULL;
blocking = false;
progress |= aio_dispatch_handlers(ctx, event);
- }
+ } while (count > 0);
progress |= timerlistgroup_run_timers(&ctx->tlg);
- aio_set_dispatching(ctx, was_dispatching);
+ aio_context_release(ctx);
return progress;
}
+
+void aio_context_setup(AioContext *ctx)
+{
+}