From abf90d39213cca30e92f6d72452a05cbf29969b8 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 12 Jan 2017 19:07:56 +0100 Subject: [PATCH] aio: tweak walking in dispatch phase Preparing for the following patch, use QLIST_FOREACH_SAFE and modify the placement of walking_handlers increment/decrement. Reviewed-by: Stefan Hajnoczi Signed-off-by: Paolo Bonzini Reviewed-by: Fam Zheng Message-id: 20170112180800.21085-7-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi --- aio-posix.c | 26 ++++++++++++-------------- aio-win32.c | 26 ++++++++++++-------------- 2 files changed, 24 insertions(+), 28 deletions(-) diff --git a/aio-posix.c b/aio-posix.c index 25198d9013..f83b7af591 100644 --- a/aio-posix.c +++ b/aio-posix.c @@ -369,19 +369,17 @@ bool aio_pending(AioContext *ctx) static bool aio_dispatch_handlers(AioContext *ctx) { - AioHandler *node; + AioHandler *node, *tmp; bool progress = false; /* * We have to walk very carefully in case aio_set_fd_handler is * called while we're walking. */ - node = QLIST_FIRST(&ctx->aio_handlers); - while (node) { - AioHandler *tmp; - int revents; + ctx->walking_handlers++; - ctx->walking_handlers++; + QLIST_FOREACH_SAFE(node, &ctx->aio_handlers, node, tmp) { + int revents; revents = node->pfd.revents & node->pfd.events; node->pfd.revents = 0; @@ -405,17 +403,17 @@ static bool aio_dispatch_handlers(AioContext *ctx) 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); + if (node->deleted) { + ctx->walking_handlers--; + if (!ctx->walking_handlers) { + QLIST_REMOVE(node, node); + g_free(node); + } + ctx->walking_handlers++; } } + ctx->walking_handlers--; return progress; } diff --git a/aio-win32.c b/aio-win32.c index d19dc429d8..1ad459d7ec 100644 --- a/aio-win32.c +++ b/aio-win32.c @@ -227,20 +227,18 @@ bool aio_pending(AioContext *ctx) static bool aio_dispatch_handlers(AioContext *ctx, HANDLE event) { - AioHandler *node; + AioHandler *node, *tmp; bool progress = false; + ctx->walking_handlers++; + /* * We have to walk very carefully in case aio_set_fd_handler is * called while we're walking. */ - node = QLIST_FIRST(&ctx->aio_handlers); - while (node) { - AioHandler *tmp; + QLIST_FOREACH_SAFE(node, &ctx->aio_handlers, node, tmp) { int revents = node->pfd.revents; - ctx->walking_handlers++; - if (!node->deleted && (revents || event_notifier_get_handle(node->e) == event) && node->io_notify) { @@ -275,17 +273,17 @@ static bool aio_dispatch_handlers(AioContext *ctx, HANDLE event) } } - tmp = node; - node = QLIST_NEXT(node, node); - - ctx->walking_handlers--; - - if (!ctx->walking_handlers && tmp->deleted) { - QLIST_REMOVE(tmp, node); - g_free(tmp); + if (node->deleted) { + ctx->walking_handlers--; + if (!ctx->walking_handlers) { + QLIST_REMOVE(node, node); + g_free(node); + } + ctx->walking_handlers++; } } + ctx->walking_handlers--; return progress; } -- 2.11.0