From patchwork Fri Jan 15 15:12:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 8042581 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 39C5CBEEE5 for ; Fri, 15 Jan 2016 15:17:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7756020434 for ; Fri, 15 Jan 2016 15:17:43 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A70412041B for ; Fri, 15 Jan 2016 15:17:42 +0000 (UTC) Received: from localhost ([::1]:47513 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aK68D-0005sG-Ss for patchwork-qemu-devel@patchwork.kernel.org; Fri, 15 Jan 2016 10:17:41 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46329) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aK63U-0005r2-QN for qemu-devel@nongnu.org; Fri, 15 Jan 2016 10:12:49 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aK63T-0006Hn-PV for qemu-devel@nongnu.org; Fri, 15 Jan 2016 10:12:48 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50134) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aK63T-0006Hd-HP for qemu-devel@nongnu.org; Fri, 15 Jan 2016 10:12:47 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id 4440B19F22F for ; Fri, 15 Jan 2016 15:12:47 +0000 (UTC) Received: from donizetti.redhat.com (ovpn-112-70.ams2.redhat.com [10.36.112.70]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u0FFCJ4o003942; Fri, 15 Jan 2016 10:12:46 -0500 From: Paolo Bonzini To: qemu-devel@nongnu.org Date: Fri, 15 Jan 2016 16:12:19 +0100 Message-Id: <1452870739-28484-17-git-send-email-pbonzini@redhat.com> In-Reply-To: <1452870739-28484-1-git-send-email-pbonzini@redhat.com> References: <1452870739-28484-1-git-send-email-pbonzini@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: stefanha@redhat.com Subject: [Qemu-devel] [PATCH 16/16] aio: push aio_context_acquire/release down to dispatching X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The AioContext data structures are now protected by list_lock and/or they are walked with FOREACH_RCU primitives. There is no need anymore to acquire the AioContext for the entire duration of aio_dispatch. Instead, just acquire it before and after invoking the callbacks. The next step is then to push it further down. Signed-off-by: Paolo Bonzini --- aio-posix.c | 15 ++++++--------- aio-win32.c | 15 +++++++-------- async.c | 2 ++ 3 files changed, 15 insertions(+), 17 deletions(-) diff --git a/aio-posix.c b/aio-posix.c index e088173..7f290cd 100644 --- a/aio-posix.c +++ b/aio-posix.c @@ -333,7 +333,9 @@ bool aio_dispatch(AioContext *ctx) if (!node->deleted && (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR)) && node->io_read) { + aio_context_acquire(ctx); node->io_read(node->opaque); + aio_context_release(ctx); /* aio_notify() does not count as progress */ if (node->opaque != &ctx->notifier) { @@ -343,7 +345,9 @@ bool aio_dispatch(AioContext *ctx) if (!node->deleted && (revents & (G_IO_OUT | G_IO_ERR)) && node->io_write) { + aio_context_acquire(ctx); node->io_write(node->opaque); + aio_context_release(ctx); progress = true; } @@ -359,7 +363,9 @@ bool aio_dispatch(AioContext *ctx) qemu_lockcnt_dec(&ctx->list_lock); /* Run our timers */ + aio_context_acquire(ctx); progress |= timerlistgroup_run_timers(&ctx->tlg); + aio_context_release(ctx); return progress; } @@ -417,7 +423,6 @@ bool aio_poll_internal(AioContext *ctx, bool blocking) bool progress; int64_t timeout; - aio_context_acquire(ctx); progress = false; /* aio_notify can avoid the expensive event_notifier_set if @@ -446,9 +451,6 @@ bool aio_poll_internal(AioContext *ctx, bool blocking) timeout = blocking ? aio_compute_timeout(ctx) : 0; /* wait until next event */ - if (timeout) { - aio_context_release(ctx); - } if (aio_epoll_check_poll(ctx, pollfds, npfd, timeout)) { AioHandler epoll_handler; @@ -463,9 +465,6 @@ bool aio_poll_internal(AioContext *ctx, bool blocking) if (blocking) { atomic_sub(&ctx->notify_me, 2); } - if (timeout) { - aio_context_acquire(ctx); - } aio_notify_accept(ctx); @@ -484,8 +483,6 @@ bool aio_poll_internal(AioContext *ctx, bool blocking) progress = true; } - aio_context_release(ctx); - return progress; } diff --git a/aio-win32.c b/aio-win32.c index 9deaf24..f7c6509 100644 --- a/aio-win32.c +++ b/aio-win32.c @@ -244,7 +244,9 @@ static bool aio_dispatch_handlers(AioContext *ctx, HANDLE event) if (!node->deleted && (revents || event_notifier_get_handle(node->e) == event) && node->io_notify) { + aio_context_acquire(ctx); node->io_notify(node->e); + aio_context_release(ctx); /* aio_notify() does not count as progress */ if (node->e != &ctx->notifier) { @@ -255,11 +257,15 @@ static bool aio_dispatch_handlers(AioContext *ctx, HANDLE event) if (!node->deleted && (node->io_read || node->io_write)) { if ((revents & G_IO_IN) && node->io_read) { + aio_context_acquire(ctx); node->io_read(node->opaque); + aio_context_release(ctx); progress = true; } if ((revents & G_IO_OUT) && node->io_write) { + aio_context_acquire(ctx); node->io_write(node->opaque); + aio_context_release(ctx); progress = true; } @@ -304,7 +310,6 @@ bool aio_poll_internal(AioContext *ctx, bool blocking) int count; int timeout; - aio_context_acquire(ctx); progress = false; /* aio_notify can avoid the expensive event_notifier_set if @@ -346,17 +351,11 @@ bool aio_poll_internal(AioContext *ctx, bool 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); if (blocking) { assert(first); atomic_sub(&ctx->notify_me, 2); } - if (timeout) { - aio_context_acquire(ctx); - } if (first) { aio_notify_accept(ctx); @@ -379,8 +378,8 @@ bool aio_poll_internal(AioContext *ctx, bool blocking) progress |= aio_dispatch_handlers(ctx, event); } while (count > 0); + aio_context_acquire(ctx); progress |= timerlistgroup_run_timers(&ctx->tlg); - aio_context_release(ctx); return progress; } diff --git a/async.c b/async.c index 7c8a792..64a135d 100644 --- a/async.c +++ b/async.c @@ -87,7 +87,9 @@ int aio_bh_poll(AioContext *ctx) ret = 1; } bh->idle = 0; + aio_context_acquire(ctx); aio_bh_call(bh); + aio_context_release(ctx); } }