From patchwork Thu May 28 15:37:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 281749 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB93FC433DF for ; Thu, 28 May 2020 15:45:07 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6D3CC2073B for ; Thu, 28 May 2020 15:45:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ixIynWnl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D3CC2073B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:51918 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jeKiQ-000429-Ii for qemu-devel@archiver.kernel.org; Thu, 28 May 2020 11:45:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:32926) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jeKbs-00046f-AV for qemu-devel@nongnu.org; Thu, 28 May 2020 11:38:20 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:40383 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jeKbr-000408-NG for qemu-devel@nongnu.org; Thu, 28 May 2020 11:38:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590680299; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Lo5ghy4/6swF4SaorYSBPt6xs1iD/Sty59dCX1STZ9g=; b=ixIynWnlM+omA1qWay5QgS5aNOTtG+CF46ELKMbTegj5lfbFpjdQZA0iAplHd2smBrX43m PPl6OpVDhAQUab0N3GwF0gSw7BCh2B8sKm+p7qG8tYRadLew5loXnpDSM7FS2cw721j+Ea 4kar33bmouuzn1o4X6hrBhhCvcdBbTI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-175-mN3beuX3OGOKdJB-3DWwCg-1; Thu, 28 May 2020 11:38:15 -0400 X-MC-Unique: mN3beuX3OGOKdJB-3DWwCg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 542B4474; Thu, 28 May 2020 15:38:14 +0000 (UTC) Received: from linux.fritz.box.com (ovpn-114-117.ams2.redhat.com [10.36.114.117]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2ACE010098AC; Thu, 28 May 2020 15:38:10 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Subject: [PATCH v6 10/12] util/async: Add aio_co_reschedule_self() Date: Thu, 28 May 2020 17:37:40 +0200 Message-Id: <20200528153742.274164-11-kwolf@redhat.com> In-Reply-To: <20200528153742.274164-1-kwolf@redhat.com> References: <20200528153742.274164-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=kwolf@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/28 03:11:04 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, marcandre.lureau@gmail.com, armbru@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Add a function that can be used to move the currently running coroutine to a different AioContext (and therefore potentially a different thread). Signed-off-by: Kevin Wolf --- include/block/aio.h | 10 ++++++++++ util/async.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+) diff --git a/include/block/aio.h b/include/block/aio.h index b2f703fa3f..c37617b404 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -17,6 +17,7 @@ #ifdef CONFIG_LINUX_IO_URING #include #endif +#include "qemu/coroutine.h" #include "qemu/queue.h" #include "qemu/event_notifier.h" #include "qemu/thread.h" @@ -654,6 +655,15 @@ static inline bool aio_node_check(AioContext *ctx, bool is_external) */ void aio_co_schedule(AioContext *ctx, struct Coroutine *co); +/** + * aio_co_reschedule_self: + * @new_ctx: the new context + * + * Move the currently running coroutine to new_ctx. If the coroutine is already + * running in new_ctx, do nothing. + */ +void coroutine_fn aio_co_reschedule_self(AioContext *new_ctx); + /** * aio_co_wake: * @co: the coroutine diff --git a/util/async.c b/util/async.c index 1319eee3bc..b68e73f488 100644 --- a/util/async.c +++ b/util/async.c @@ -559,6 +559,36 @@ void aio_co_schedule(AioContext *ctx, Coroutine *co) aio_context_unref(ctx); } +typedef struct AioCoRescheduleSelf { + Coroutine *co; + AioContext *new_ctx; +} AioCoRescheduleSelf; + +static void aio_co_reschedule_self_bh(void *opaque) +{ + AioCoRescheduleSelf *data = opaque; + aio_co_schedule(data->new_ctx, data->co); +} + +void coroutine_fn aio_co_reschedule_self(AioContext *new_ctx) +{ + AioContext *old_ctx = qemu_get_current_aio_context(); + + if (old_ctx != new_ctx) { + AioCoRescheduleSelf data = { + .co = qemu_coroutine_self(), + .new_ctx = new_ctx, + }; + /* + * We can't directly schedule the coroutine in the target context + * because this would be racy: The other thread could try to enter the + * coroutine before it has yielded in this one. + */ + aio_bh_schedule_oneshot(old_ctx, aio_co_reschedule_self_bh, &data); + qemu_coroutine_yield(); + } +} + void aio_co_wake(struct Coroutine *co) { AioContext *ctx;