From 6b5f876252b7aeec43e319afdf17705f512be2bc Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 20 Feb 2013 11:28:32 +0100 Subject: aio: convert aio_poll() to g_poll(3) AioHandler already has a GPollFD so we can directly use its events/revents. Add the int pollfds_idx field to AioContext so we can map g_poll(3) results back to AioHandlers. Reuse aio_dispatch() to invoke handlers after g_poll(3). Signed-off-by: Stefan Hajnoczi Reviewed-by: Laszlo Ersek Message-id: 1361356113-11049-10-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori --- aio-posix.c | 67 ++++++++++++++++++++++--------------------------------------- 1 file changed, 24 insertions(+), 43 deletions(-) (limited to 'aio-posix.c') diff --git a/aio-posix.c b/aio-posix.c index 35131a3ef7..d755e16ee8 100644 --- a/aio-posix.c +++ b/aio-posix.c @@ -25,6 +25,7 @@ struct AioHandler IOHandler *io_write; AioFlushHandler *io_flush; int deleted; + int pollfds_idx; void *opaque; QLIST_ENTRY(AioHandler) node; }; @@ -85,6 +86,7 @@ void aio_set_fd_handler(AioContext *ctx, node->io_write = io_write; node->io_flush = io_flush; node->opaque = opaque; + node->pollfds_idx = -1; node->pfd.events = (io_read ? G_IO_IN | G_IO_HUP : 0); node->pfd.events |= (io_write ? G_IO_OUT : 0); @@ -177,10 +179,7 @@ static bool aio_dispatch(AioContext *ctx) bool aio_poll(AioContext *ctx, bool blocking) { - static struct timeval tv0; AioHandler *node; - fd_set rdfds, wrfds; - int max_fd = -1; int ret; bool busy, progress; @@ -206,12 +205,13 @@ bool aio_poll(AioContext *ctx, bool blocking) ctx->walking_handlers++; - FD_ZERO(&rdfds); - FD_ZERO(&wrfds); + g_array_set_size(ctx->pollfds, 0); - /* fill fd sets */ + /* fill pollfds */ busy = false; QLIST_FOREACH(node, &ctx->aio_handlers, node) { + node->pollfds_idx = -1; + /* If there aren't pending AIO operations, don't invoke callbacks. * Otherwise, if there are no AIO requests, qemu_aio_wait() would * wait indefinitely. @@ -222,13 +222,13 @@ bool aio_poll(AioContext *ctx, bool blocking) } busy = true; } - if (!node->deleted && node->io_read) { - FD_SET(node->pfd.fd, &rdfds); - max_fd = MAX(max_fd, node->pfd.fd + 1); - } - if (!node->deleted && node->io_write) { - FD_SET(node->pfd.fd, &wrfds); - max_fd = MAX(max_fd, node->pfd.fd + 1); + if (!node->deleted && node->pfd.events) { + GPollFD pfd = { + .fd = node->pfd.fd, + .events = node->pfd.events, + }; + node->pollfds_idx = ctx->pollfds->len; + g_array_append_val(ctx->pollfds, pfd); } } @@ -240,41 +240,22 @@ bool aio_poll(AioContext *ctx, bool blocking) } /* wait until next event */ - ret = select(max_fd, &rdfds, &wrfds, NULL, blocking ? NULL : &tv0); + ret = g_poll((GPollFD *)ctx->pollfds->data, + ctx->pollfds->len, + blocking ? -1 : 0); /* if we have any readable fds, dispatch event */ if (ret > 0) { - /* we have to walk very carefully in case - * qemu_aio_set_fd_handler is called while we're walking */ - node = QLIST_FIRST(&ctx->aio_handlers); - while (node) { - AioHandler *tmp; - - ctx->walking_handlers++; - - if (!node->deleted && - FD_ISSET(node->pfd.fd, &rdfds) && - node->io_read) { - node->io_read(node->opaque); - progress = true; - } - if (!node->deleted && - FD_ISSET(node->pfd.fd, &wrfds) && - node->io_write) { - node->io_write(node->opaque); - progress = true; - } - - tmp = node; - node = QLIST_NEXT(node, node); - - ctx->walking_handlers--; - - if (!ctx->walking_handlers && tmp->deleted) { - QLIST_REMOVE(tmp, node); - g_free(tmp); + QLIST_FOREACH(node, &ctx->aio_handlers, node) { + if (node->pollfds_idx != -1) { + GPollFD *pfd = &g_array_index(ctx->pollfds, GPollFD, + node->pollfds_idx); + node->pfd.revents = pfd->revents; } } + if (aio_dispatch(ctx)) { + progress = true; + } } assert(progress || busy); -- cgit v1.2.3