From patchwork Tue Jul 19 12:27:42 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roman Pen X-Patchwork-Id: 650155 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3rtzqg13N4z9s5J for ; Tue, 19 Jul 2016 22:29:03 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=profitbricks-com.20150623.gappssmtp.com header.i=@profitbricks-com.20150623.gappssmtp.com header.b=RRL14y/g; dkim-atps=neutral Received: from localhost ([::1]:55536 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bPU8y-0007vB-Tt for incoming@patchwork.ozlabs.org; Tue, 19 Jul 2016 08:29:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36181) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bPU80-0006Sg-Pc for qemu-devel@nongnu.org; Tue, 19 Jul 2016 08:28:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bPU7z-0005eh-9d for qemu-devel@nongnu.org; Tue, 19 Jul 2016 08:28:00 -0400 Received: from mail-wm0-x235.google.com ([2a00:1450:400c:c09::235]:38751) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bPU7z-0005eb-31 for qemu-devel@nongnu.org; Tue, 19 Jul 2016 08:27:59 -0400 Received: by mail-wm0-x235.google.com with SMTP id o80so24385896wme.1 for ; Tue, 19 Jul 2016 05:27:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=profitbricks-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=6UH+3YJP9LdYNhY/GMuWPXX92yYw3YYwViMSV6vwiwc=; b=RRL14y/gf7f41/xD9MHcp+q7V3AhnlK5yM6X0noaD2DUVL0F1i1gecKqqvGuc8dluK fhgtkJgt+K0tIbDr5qLwe37P6GwKbCg7jCQBbyMYvWO3vhTVAfGxqe9qiTZSi07l91r4 BMniuTf626IVrhAVj8iXo2PLnrY2Ep3o4XCkc96p9xVVzj939F8hy5maW4glOYog4omH osW17MQ+SIFRx6pLvvMM/f/Bv5VJZCesLKmFuSdH5G7NVB8AYZyPQXLXvQk8Y6n63jfP 0rK/FwuY8Naf8qhIp09WIlyyFZo20hJVpRFEFl4ymTmfrQ5c8SYH2uTLbt6oTtibtDvp x/3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=6UH+3YJP9LdYNhY/GMuWPXX92yYw3YYwViMSV6vwiwc=; b=agtHPWOvqp5PZW/KMV8BbKGmcnvJHr6nRzpUKwxzDmWOx7uIltbZ5+tpdPHjgc9auQ UYXVOZ5IskEjfvV96A5wwD8irOW6RhzygNWUTQoMdwpmVYADGH9doEmO6/nPTeYfS1gC rmIC4G5b74Icu4F5RZ2EWQAQKVRpbxaKBbvy+ATf1ebcDp08z+vBJbUT5oqIHJInMrgd 4FvRQyCfHfiN6Ml0UWSkoi1WCE9BJmYMfPI/6MKMUrpSZZvGG5W0p83jk1Tv1NL4y07l MJNlPUwHK25kKNdV6hB4nIpk31ZHehWWkpjX0gI/Yb2ocGC5VSLVf/ExCXd7H639FMdW qJSQ== X-Gm-Message-State: ALyK8tKWuByIyi/loX+8kLG/nR1/yYSNlOGDTCyJjysPec0KHosnF6IF19L/e+AB1diaa8qC X-Received: by 10.28.37.134 with SMTP id l128mr4064547wml.49.1468931278399; Tue, 19 Jul 2016 05:27:58 -0700 (PDT) Received: from pb.pb.local ([62.217.45.26]) by smtp.gmail.com with ESMTPSA id d62sm22581855wmd.7.2016.07.19.05.27.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 19 Jul 2016 05:27:57 -0700 (PDT) From: Roman Pen To: Date: Tue, 19 Jul 2016 14:27:42 +0200 Message-Id: <1468931263-32667-3-git-send-email-roman.penyaev@profitbricks.com> X-Mailer: git-send-email 2.8.2 In-Reply-To: <1468931263-32667-1-git-send-email-roman.penyaev@profitbricks.com> References: <1468931263-32667-1-git-send-email-roman.penyaev@profitbricks.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:400c:c09::235 Subject: [Qemu-devel] [PATCH v2 2/3] linux-aio: split processing events function X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Stefan Hajnoczi , Roman Pen , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Prepare processing events function to be called from ioq_submit(), thus split function on two parts: the first harvests completed IO requests, the second submits pending requests. Signed-off-by: Roman Pen Cc: Stefan Hajnoczi Cc: Paolo Bonzini Cc: qemu-devel@nongnu.org --- block/linux-aio.c | 31 +++++++++++++++++++++---------- 1 file changed, 21 insertions(+), 10 deletions(-) diff --git a/block/linux-aio.c b/block/linux-aio.c index 3e29f1d..fae5c82 100644 --- a/block/linux-aio.c +++ b/block/linux-aio.c @@ -178,20 +178,20 @@ io_getevents_advance_and_peek(io_context_t ctx, return io_getevents_peek(ctx, events); } -/* The completion BH fetches completed I/O requests and invokes their - * callbacks. +/** + * qemu_laio_process_completions: + * @s: AIO state + * + * Fetches completed I/O requests and invokes their callbacks. * * The function is somewhat tricky because it supports nested event loops, for * example when a request callback invokes aio_poll(). In order to do this, - * the completion events array and index are kept in LinuxAioState. The BH - * reschedules itself as long as there are completions pending so it will - * either be called again in a nested event loop or will be called after all - * events have been completed. When there are no events left to complete, the - * BH returns without rescheduling. + * indices are kept in LinuxAioState. Function schedules BH completion so it + * can be called again in a nested event loop. When there are no events left + * to complete the BH is being canceled. */ -static void qemu_laio_completion_bh(void *opaque) +static void qemu_laio_process_completions(LinuxAioState *s) { - LinuxAioState *s = opaque; struct io_event *events; /* Reschedule so nested event loops see currently pending completions */ @@ -220,18 +220,29 @@ static void qemu_laio_completion_bh(void *opaque) * own `for` loop. If we are the last all counters droped to zero. */ s->event_max = 0; s->event_idx = 0; +} +static void qemu_laio_process_completions_and_submit(LinuxAioState *s) +{ + qemu_laio_process_completions(s); if (!s->io_q.plugged && !QSIMPLEQ_EMPTY(&s->io_q.pending)) { ioq_submit(s); } } +static void qemu_laio_completion_bh(void *opaque) +{ + LinuxAioState *s = opaque; + + qemu_laio_process_completions_and_submit(s); +} + static void qemu_laio_completion_cb(EventNotifier *e) { LinuxAioState *s = container_of(e, LinuxAioState, e); if (event_notifier_test_and_clear(&s->e)) { - qemu_laio_completion_bh(s); + qemu_laio_process_completions_and_submit(s); } }