From patchwork Thu May 31 00:43:23 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Snow X-Patchwork-Id: 10440119 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id AB45A60380 for ; Thu, 31 May 2018 00:44:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9E67B29388 for ; Thu, 31 May 2018 00:44:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9371F2939B; Thu, 31 May 2018 00:44:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3320129388 for ; Thu, 31 May 2018 00:44:53 +0000 (UTC) Received: from localhost ([::1]:41355 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fOBi0-0006Pz-FZ for patchwork-qemu-devel@patchwork.kernel.org; Wed, 30 May 2018 20:44:52 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59172) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fOBgf-0005Go-FC for qemu-devel@nongnu.org; Wed, 30 May 2018 20:43:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fOBge-0006uE-OD for qemu-devel@nongnu.org; Wed, 30 May 2018 20:43:29 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:43446 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fOBgb-0006sS-6k; Wed, 30 May 2018 20:43:25 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BC0FA818BAF8; Thu, 31 May 2018 00:43:24 +0000 (UTC) Received: from probe.bos.redhat.com (dhcp-17-177.bos.redhat.com [10.18.17.177]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7F064200A4B6; Thu, 31 May 2018 00:43:24 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org, qemu-block@nongnu.org Date: Wed, 30 May 2018 20:43:23 -0400 Message-Id: <20180531004323.4611-4-jsnow@redhat.com> In-Reply-To: <20180531004323.4611-1-jsnow@redhat.com> References: <20180531004323.4611-1-jsnow@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Thu, 31 May 2018 00:43:24 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Thu, 31 May 2018 00:43:24 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jsnow@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH 3/3] ahci: don't schedule unnecessary BH 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: John Snow Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The comment gives us a hint. *Maybe* we still have something to process. Well, why not check? Signed-off-by: John Snow Reviewed-by: Jeff Cody --- hw/ide/ahci.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c index a9558e45e7..380366b038 100644 --- a/hw/ide/ahci.c +++ b/hw/ide/ahci.c @@ -1427,8 +1427,7 @@ static void ahci_cmd_done(IDEDMA *dma) /* update d2h status */ ahci_write_fis_d2h(ad); - if (!ad->check_bh) { - /* maybe we still have something to process, check later */ + if (ad->port_regs.cmd_issue && !ad->check_bh) { ad->check_bh = qemu_bh_new(ahci_check_cmd_bh, ad); qemu_bh_schedule(ad->check_bh); }