From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54798) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a1HvZ-0002Q0-H6 for qemu-devel@nongnu.org; Tue, 24 Nov 2015 13:02:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a1HvW-00069a-7J for qemu-devel@nongnu.org; Tue, 24 Nov 2015 13:02:53 -0500 From: Paolo Bonzini Date: Tue, 24 Nov 2015 19:01:29 +0100 Message-Id: <1448388091-117282-39-git-send-email-pbonzini@redhat.com> In-Reply-To: <1448388091-117282-1-git-send-email-pbonzini@redhat.com> References: <1448388091-117282-1-git-send-email-pbonzini@redhat.com> Subject: [Qemu-devel] [PATCH 38/40] aio-posix: partially inline aio_dispatch into aio_poll List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, qemu-block@nongnu.org This patch prepares for the removal of unnecessary lockcnt inc/dec pairs. Extract the dispatching loop for file descriptor handlers into a new function aio_dispatch_handlers, and then inline aio_dispatch into aio_poll. aio_dispatch can now become void. Signed-off-by: Paolo Bonzini --- aio-posix.c | 41 +++++++++++++++++------------------------ aio-win32.c | 11 ++++------- include/block/aio.h | 2 +- 3 files changed, 22 insertions(+), 32 deletions(-) diff --git a/aio-posix.c b/aio-posix.c index aabc4ae..b372816 100644 --- a/aio-posix.c +++ b/aio-posix.c @@ -305,26 +305,11 @@ bool aio_pending(AioContext *ctx) return result; } -bool aio_dispatch(AioContext *ctx) +static bool aio_dispatch_handlers(AioContext *ctx) { AioHandler *node, *tmp; bool progress = false; - /* - * If there are callbacks left that have been queued, we need to call them. - * Do not call select in this case, because it is possible that the caller - * does not need a complete flush (as is the case for aio_poll loops). - */ - if (aio_bh_poll(ctx)) { - progress = true; - } - - /* - * We have to walk very carefully in case aio_set_fd_handler is - * called while we're walking. - */ - qemu_lockcnt_inc(&ctx->list_lock); - QLIST_FOREACH_SAFE_RCU(node, &ctx->aio_handlers, node, tmp) { int revents; @@ -356,12 +341,18 @@ bool aio_dispatch(AioContext *ctx) } } - qemu_lockcnt_dec(&ctx->list_lock); + return progress; +} - /* Run our timers */ - progress |= timerlistgroup_run_timers(&ctx->tlg); +void aio_dispatch(AioContext *ctx) +{ + aio_bh_poll(ctx); - return progress; + qemu_lockcnt_inc(&ctx->list_lock); + aio_dispatch_handlers(ctx); + qemu_lockcnt_dec(&ctx->list_lock); + + timerlistgroup_run_timers(&ctx->tlg); } /* These thread-local variables are used only in a small part of aio_poll @@ -472,11 +463,13 @@ bool aio_poll(AioContext *ctx, bool blocking) npfd = 0; qemu_lockcnt_dec(&ctx->list_lock); - /* Run dispatch even if there were no readable fds to run timers */ - if (aio_dispatch(ctx)) { - progress = true; - } + progress |= aio_bh_poll(ctx); + + qemu_lockcnt_inc(&ctx->list_lock); + progress |= aio_dispatch_handlers(ctx); + qemu_lockcnt_dec(&ctx->list_lock); + progress |= timerlistgroup_run_timers(&ctx->tlg); return progress; } diff --git a/aio-win32.c b/aio-win32.c index 4479d3f..feffdc4 100644 --- a/aio-win32.c +++ b/aio-win32.c @@ -286,14 +286,11 @@ static bool aio_dispatch_handlers(AioContext *ctx, HANDLE event) return progress; } -bool aio_dispatch(AioContext *ctx) +void aio_dispatch(AioContext *ctx) { - bool progress; - - progress = aio_bh_poll(ctx); - progress |= aio_dispatch_handlers(ctx, INVALID_HANDLE_VALUE); - progress |= timerlistgroup_run_timers(&ctx->tlg); - return progress; + aio_bh_poll(ctx); + aio_dispatch_handlers(ctx, INVALID_HANDLE_VALUE); + timerlistgroup_run_timers(&ctx->tlg); } bool aio_poll(AioContext *ctx, bool blocking) diff --git a/include/block/aio.h b/include/block/aio.h index 21044af..05a41b2 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -277,7 +277,7 @@ bool aio_pending(AioContext *ctx); * * This is used internally in the implementation of the GSource. */ -bool aio_dispatch(AioContext *ctx); +void aio_dispatch(AioContext *ctx); /* Progress in completing AIO work to occur. This can issue new pending * aio as a result of executing I/O completion or bh callbacks. -- 1.8.3.1