From patchwork Wed Jul 6 20:15:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 12908695 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 6B108C43334 for ; Wed, 6 Jul 2022 21:49:11 +0000 (UTC) Received: from localhost ([::1]:56478 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1o9CtS-0002Yt-Ds for qemu-devel@archiver.kernel.org; Wed, 06 Jul 2022 17:49:10 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39216) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o9BRB-0005En-8Z for qemu-devel@nongnu.org; Wed, 06 Jul 2022 16:15:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:55337) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o9BR7-0007ET-0S for qemu-devel@nongnu.org; Wed, 06 Jul 2022 16:15:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1657138548; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pXXEWuTZjbY86kMHhS2xb1I9DX+F+DsvFH6sb6NeVxc=; b=WuTqkr2GHQOAvwUJm5giWYcvZs1y82AtEnHo5rnTw5xhrzWschYF9IoR0EgN/K/H6K6w6/ Un++nRdyRc30fuAff2o915z5/jRYxrrZ/dlFWv93ZIK/UmDxlHI55LIIUYTHXWeoKTxpWI pGSlLpwQvHT6R2Bxh0fCrIaf/dynhR4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-673-x8_kpHriP6iI9R3Q3p2Snw-1; Wed, 06 Jul 2022 16:15:44 -0400 X-MC-Unique: x8_kpHriP6iI9R3Q3p2Snw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 44B55101A59F; Wed, 6 Jul 2022 20:15:43 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id DDD6C1121320; Wed, 6 Jul 2022 20:15:42 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Cc: Kevin Wolf , Hanna Reitz , Paolo Bonzini , John Snow , Vladimir Sementsov-Ogievskiy , Wen Congyang , Xie Changlong , Markus Armbruster , Stefan Hajnoczi , Fam Zheng , qemu-devel@nongnu.org, Emanuele Giuseppe Esposito , Vladimir Sementsov-Ogievskiy Subject: [PATCH v9 04/21] aio-wait.h: introduce AIO_WAIT_WHILE_UNLOCKED Date: Wed, 6 Jul 2022 16:15:16 -0400 Message-Id: <20220706201533.289775-5-eesposit@redhat.com> In-Reply-To: <20220706201533.289775-1-eesposit@redhat.com> References: <20220706201533.289775-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Same as AIO_WAIT_WHILE macro, but if we are in the Main loop do not release and then acquire ctx_ 's aiocontext. Once all Aiocontext locks go away, this macro will replace AIO_WAIT_WHILE. Signed-off-by: Emanuele Giuseppe Esposito Reviewed-by: Stefan Hajnoczi Reviewed-by: Vladimir Sementsov-Ogievskiy --- include/block/aio-wait.h | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/include/block/aio-wait.h b/include/block/aio-wait.h index 54840f8622..a61f82c617 100644 --- a/include/block/aio-wait.h +++ b/include/block/aio-wait.h @@ -59,10 +59,13 @@ typedef struct { extern AioWait global_aio_wait; /** - * AIO_WAIT_WHILE: + * _AIO_WAIT_WHILE: * @ctx: the aio context, or NULL if multiple aio contexts (for which the * caller does not hold a lock) are involved in the polling condition. * @cond: wait while this conditional expression is true + * @unlock: whether to unlock and then lock again @ctx. This apples + * only when waiting for another AioContext from the main loop. + * Otherwise it's ignored. * * Wait while a condition is true. Use this to implement synchronous * operations that require event loop activity. @@ -75,7 +78,7 @@ extern AioWait global_aio_wait; * wait on conditions between two IOThreads since that could lead to deadlock, * go via the main loop instead. */ -#define AIO_WAIT_WHILE(ctx, cond) ({ \ +#define _AIO_WAIT_WHILE(ctx, cond, unlock) ({ \ bool waited_ = false; \ AioWait *wait_ = &global_aio_wait; \ AioContext *ctx_ = (ctx); \ @@ -92,11 +95,11 @@ extern AioWait global_aio_wait; assert(qemu_get_current_aio_context() == \ qemu_get_aio_context()); \ while ((cond)) { \ - if (ctx_) { \ + if (unlock && ctx_) { \ aio_context_release(ctx_); \ } \ aio_poll(qemu_get_aio_context(), true); \ - if (ctx_) { \ + if (unlock && ctx_) { \ aio_context_acquire(ctx_); \ } \ waited_ = true; \ @@ -105,6 +108,12 @@ extern AioWait global_aio_wait; qatomic_dec(&wait_->num_waiters); \ waited_; }) +#define AIO_WAIT_WHILE(ctx, cond) \ + _AIO_WAIT_WHILE(ctx, cond, true) + +#define AIO_WAIT_WHILE_UNLOCKED(ctx, cond) \ + _AIO_WAIT_WHILE(ctx, cond, false) + /** * aio_wait_kick: * Wake up the main thread if it is waiting on AIO_WAIT_WHILE(). During