From patchwork Tue Jun 8 07:33:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 1489145 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=R6EyrcYO; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 4Fzhqv1z2pz9s24 for ; Tue, 8 Jun 2021 17:36:11 +1000 (AEST) Received: from localhost ([::1]:42750 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lqWHR-0008G8-9o for incoming@patchwork.ozlabs.org; Tue, 08 Jun 2021 03:36:09 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51740) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lqWFS-0003Vc-Ls for qemu-devel@nongnu.org; Tue, 08 Jun 2021 03:34:06 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:28945) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lqWFQ-0005GI-Ot for qemu-devel@nongnu.org; Tue, 08 Jun 2021 03:34:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623137644; 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=3kh0KqmdCWNV7x5VvloIjB4t8//cjeCMhlFWcIJ19HY=; b=R6EyrcYOgP97TASXnXjdO59nHKwgNm/xgCK0t89GlwEySTaj7jFhgVf3T1vYEwMPry5XId W0+rCKVqPmzbCs5tByB00GMjo+reN2ShfRLRvfASUia76n0ZFG/FMor/8b/Jzfb37m1dP/ Le3sUxeW4vAX1zaIP7r9u6zWrFMNB38= 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-160-vn1hwRGYPzKIhsFDNHCRrQ-1; Tue, 08 Jun 2021 03:34:02 -0400 X-MC-Unique: vn1hwRGYPzKIhsFDNHCRrQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3B5FB107ACCA; Tue, 8 Jun 2021 07:34:01 +0000 (UTC) Received: from localhost.localdomain (ovpn-113-225.ams2.redhat.com [10.36.113.225]) by smtp.corp.redhat.com (Postfix) with ESMTP id EC604608BA; Tue, 8 Jun 2021 07:33:58 +0000 (UTC) From: Emanuele Giuseppe Esposito To: qemu-block@nongnu.org Subject: [PATCH v3 5/5] block-copy: atomic .cancelled and .finished fields in BlockCopyCallState Date: Tue, 8 Jun 2021 09:33:44 +0200 Message-Id: <20210608073344.53637-6-eesposit@redhat.com> In-Reply-To: <20210608073344.53637-1-eesposit@redhat.com> References: <20210608073344.53637-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eesposit@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=eesposit@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.2, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no 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: Kevin Wolf , Emanuele Giuseppe Esposito , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, Max Reitz , Stefan Hajnoczi , Paolo Bonzini , John Snow Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" By adding acquire/release pairs, we ensure that .ret and .error_is_read fields are written by block_copy_dirty_clusters before .finished is true. The atomic here are necessary because the fields are concurrently modified also outside coroutines. Signed-off-by: Emanuele Giuseppe Esposito --- block/block-copy.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/block/block-copy.c b/block/block-copy.c index 56f62913e4..55b6ce6a57 100644 --- a/block/block-copy.c +++ b/block/block-copy.c @@ -56,11 +56,11 @@ typedef struct BlockCopyCallState { QLIST_ENTRY(BlockCopyCallState) list; /* State */ - bool finished; + bool finished; /* atomic */ QemuCoSleep sleep; /* TODO: protect API with a lock */ /* OUT parameters */ - bool cancelled; + bool cancelled; /* atomic */ /* Fields protected by lock in BlockCopyState */ bool error_is_read; int ret; @@ -648,7 +648,8 @@ block_copy_dirty_clusters(BlockCopyCallState *call_state) assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); assert(QEMU_IS_ALIGNED(bytes, s->cluster_size)); - while (bytes && aio_task_pool_status(aio) == 0 && !call_state->cancelled) { + while (bytes && aio_task_pool_status(aio) == 0 && + !qatomic_read(&call_state->cancelled)) { BlockCopyTask *task; int64_t status_bytes; @@ -758,7 +759,7 @@ static int coroutine_fn block_copy_common(BlockCopyCallState *call_state) do { ret = block_copy_dirty_clusters(call_state); - if (ret == 0 && !call_state->cancelled) { + if (ret == 0 && !qatomic_read(&call_state->cancelled)) { ret = block_copy_wait_one(call_state->s, call_state->offset, call_state->bytes); } @@ -772,9 +773,9 @@ static int coroutine_fn block_copy_common(BlockCopyCallState *call_state) * 2. We have waited for some intersecting block-copy request * It may have failed and produced new dirty bits. */ - } while (ret > 0 && !call_state->cancelled); + } while (ret > 0 && !qatomic_read(&call_state->cancelled)); - call_state->finished = true; + qatomic_store_release(&call_state->finished, true); if (call_state->cb) { call_state->cb(call_state->cb_opaque); @@ -837,35 +838,37 @@ void block_copy_call_free(BlockCopyCallState *call_state) return; } - assert(call_state->finished); + assert(qatomic_load_acquire(&call_state->finished)); g_free(call_state); } bool block_copy_call_finished(BlockCopyCallState *call_state) { - return call_state->finished; + return qatomic_load_acquire(&call_state->finished); } bool block_copy_call_succeeded(BlockCopyCallState *call_state) { - return call_state->finished && !call_state->cancelled && - call_state->ret == 0; + return qatomic_load_acquire(&call_state->finished) && + !qatomic_read(&call_state->cancelled) && + call_state->ret == 0; } bool block_copy_call_failed(BlockCopyCallState *call_state) { - return call_state->finished && !call_state->cancelled && - call_state->ret < 0; + return qatomic_load_acquire(&call_state->finished) && + !qatomic_read(&call_state->cancelled) && + call_state->ret < 0; } bool block_copy_call_cancelled(BlockCopyCallState *call_state) { - return call_state->cancelled; + return qatomic_read(&call_state->cancelled); } int block_copy_call_status(BlockCopyCallState *call_state, bool *error_is_read) { - assert(call_state->finished); + assert(qatomic_load_acquire(&call_state->finished)); if (error_is_read) { *error_is_read = call_state->error_is_read; } @@ -874,7 +877,7 @@ int block_copy_call_status(BlockCopyCallState *call_state, bool *error_is_read) void block_copy_call_cancel(BlockCopyCallState *call_state) { - call_state->cancelled = true; + qatomic_set(&call_state->cancelled, true); block_copy_kick(call_state); }