From patchwork Thu Mar 26 15:36:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 1262082 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; dmarc=fail (p=none dis=none) header.from=redhat.com 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=TbbAxGUn; 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 48p8Jb4d0Zz9sRR for ; Fri, 27 Mar 2020 02:38:07 +1100 (AEDT) Received: from localhost ([::1]:55536 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jHUa5-000674-Hu for incoming@patchwork.ozlabs.org; Thu, 26 Mar 2020 11:38:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54458) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jHUYn-0005Vn-5p for qemu-devel@nongnu.org; Thu, 26 Mar 2020 11:36:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jHUYk-0002rO-M1 for qemu-devel@nongnu.org; Thu, 26 Mar 2020 11:36:44 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:49948) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jHUYi-0002pW-Ou for qemu-devel@nongnu.org; Thu, 26 Mar 2020 11:36:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585236999; 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=/8wyeUj06KXeS38TLcF04SKwHtzws1PB37ZwA+U4vxc=; b=TbbAxGUnv74qSx9Kwo1eEg4JTcy4dUZnRvkjDAo4prnUu0IwOfvJnmnzUuTMD2mDPAZ8s1 KPdTYWWbRb7YtQcqj27qWyWdc5W3s3XN6kMh38J5cPGmq7C2Cec9VDzks+WRLgTAXzdSYr d2dGL0dQ2AOdwVzW7S5x7lfB8RvzXY8= 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-306-NJixbO6bMdeyNjBOvkuDZw-1; Thu, 26 Mar 2020 11:36:37 -0400 X-MC-Unique: NJixbO6bMdeyNjBOvkuDZw-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 EEEB0A0CBF; Thu, 26 Mar 2020 15:36:36 +0000 (UTC) Received: from linux.fritz.box.com (ovpn-112-205.ams2.redhat.com [10.36.112.205]) by smtp.corp.redhat.com (Postfix) with ESMTP id A4A2D5C1BA; Thu, 26 Mar 2020 15:36:35 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Subject: [PATCH v2 1/2] Revert "mirror: Don't let an operation wait for itself" Date: Thu, 26 Mar 2020 16:36:27 +0100 Message-Id: <20200326153628.4869-2-kwolf@redhat.com> In-Reply-To: <20200326153628.4869-1-kwolf@redhat.com> References: <20200326153628.4869-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 63.128.21.74 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, jsnow@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This reverts commit 7e6c4ff792734e196c8ca82564c56b5e7c6288ca. The fix was incomplete as it only protected against requests waiting for themselves, but not against requests waiting for each other. We need a different solution. Signed-off-by: Kevin Wolf --- block/mirror.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index 447051dbc6..393131b135 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -283,14 +283,11 @@ static int mirror_cow_align(MirrorBlockJob *s, int64_t *offset, } static inline void coroutine_fn -mirror_wait_for_any_operation(MirrorBlockJob *s, MirrorOp *self, bool active) +mirror_wait_for_any_operation(MirrorBlockJob *s, bool active) { MirrorOp *op; QTAILQ_FOREACH(op, &s->ops_in_flight, next) { - if (self == op) { - continue; - } /* Do not wait on pseudo ops, because it may in turn wait on * some other operation to start, which may in fact be the * caller of this function. Since there is only one pseudo op @@ -305,10 +302,10 @@ mirror_wait_for_any_operation(MirrorBlockJob *s, MirrorOp *self, bool active) } static inline void coroutine_fn -mirror_wait_for_free_in_flight_slot(MirrorBlockJob *s, MirrorOp *self) +mirror_wait_for_free_in_flight_slot(MirrorBlockJob *s) { /* Only non-active operations use up in-flight slots */ - mirror_wait_for_any_operation(s, self, false); + mirror_wait_for_any_operation(s, false); } /* Perform a mirror copy operation. @@ -351,7 +348,7 @@ static void coroutine_fn mirror_co_read(void *opaque) while (s->buf_free_count < nb_chunks) { trace_mirror_yield_in_flight(s, op->offset, s->in_flight); - mirror_wait_for_free_in_flight_slot(s, op); + mirror_wait_for_free_in_flight_slot(s); } /* Now make a QEMUIOVector taking enough granularity-sized chunks @@ -558,7 +555,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) while (s->in_flight >= MAX_IN_FLIGHT) { trace_mirror_yield_in_flight(s, offset, s->in_flight); - mirror_wait_for_free_in_flight_slot(s, pseudo_op); + mirror_wait_for_free_in_flight_slot(s); } if (s->ret < 0) { @@ -612,7 +609,7 @@ static void mirror_free_init(MirrorBlockJob *s) static void coroutine_fn mirror_wait_for_all_io(MirrorBlockJob *s) { while (s->in_flight > 0) { - mirror_wait_for_free_in_flight_slot(s, NULL); + mirror_wait_for_free_in_flight_slot(s); } } @@ -809,7 +806,7 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) if (s->in_flight >= MAX_IN_FLIGHT) { trace_mirror_yield(s, UINT64_MAX, s->buf_free_count, s->in_flight); - mirror_wait_for_free_in_flight_slot(s, NULL); + mirror_wait_for_free_in_flight_slot(s); continue; } @@ -962,7 +959,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) /* Do not start passive operations while there are active * writes in progress */ while (s->in_active_write_counter) { - mirror_wait_for_any_operation(s, NULL, true); + mirror_wait_for_any_operation(s, true); } if (s->ret < 0) { @@ -988,7 +985,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp) if (s->in_flight >= MAX_IN_FLIGHT || s->buf_free_count == 0 || (cnt == 0 && s->in_flight > 0)) { trace_mirror_yield(s, cnt, s->buf_free_count, s->in_flight); - mirror_wait_for_free_in_flight_slot(s, NULL); + mirror_wait_for_free_in_flight_slot(s); continue; } else if (cnt != 0) { delay_ns = mirror_iteration(s);