From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 B20BEC2BB1D for ; Thu, 9 Apr 2020 01:24:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A9FF2085B for ; Thu, 9 Apr 2020 01:24:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HFf879Xb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726654AbgDIBYw (ORCPT ); Wed, 8 Apr 2020 21:24:52 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:34518 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726552AbgDIBYw (ORCPT ); Wed, 8 Apr 2020 21:24:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1586395492; 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: in-reply-to:in-reply-to:references:references; bh=NbqUujqUBgWimkq47tbzopEW+FIVMfLk+fggqhU1i0c=; b=HFf879XbJCOPWBf9EO9dJ9rR9VSmiMKhMsurL47+DmO0z2UP3nDRN1liMjBQH8fv6X+qe2 PgNJha53Rgoc7MLk35QrYEApDRfv8fcbUMn5aF7F3j0oKRw2+eFqfrjXYh/iC0nDOiCQ0R GysrQ33whGywK0ylaEVaOavFzQ1QC5c= 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-279-qVDO5DX0OIiAl8SojBTAHw-1; Wed, 08 Apr 2020 21:24:48 -0400 X-MC-Unique: qVDO5DX0OIiAl8SojBTAHw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4FB808017F5; Thu, 9 Apr 2020 01:24:46 +0000 (UTC) Received: from localhost.localdomain (ovpn-8-27.pek2.redhat.com [10.72.8.27]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7DF1A46; Thu, 9 Apr 2020 01:24:35 +0000 (UTC) Date: Thu, 9 Apr 2020 09:24:30 +0800 From: Ming Lei To: Douglas Anderson Cc: axboe@kernel.dk, jejb@linux.ibm.com, martin.petersen@oracle.com, paolo.valente@linaro.org, groeck@chromium.org, Gwendal Grignou , linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, sqazi@google.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 4/4] Revert "scsi: core: run queue if SCSI device queue isn't ready and queue is idle" Message-ID: <20200409012430.GC369792@localhost.localdomain> References: <20200408150402.21208-1-dianders@chromium.org> <20200408080255.v4.4.I630e6ca4cdcf9ab13ea899274745f9e3174eb12b@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200408080255.v4.4.I630e6ca4cdcf9ab13ea899274745f9e3174eb12b@changeid> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 08, 2020 at 08:04:02AM -0700, Douglas Anderson wrote: > This reverts commit 7e70aa789d4a0c89dbfbd2c8a974a4df717475ec. > > Now that we have the patches ("blk-mq: In blk_mq_dispatch_rq_list() > "no budget" is a reason to kick") and ("blk-mq: Rerun dispatching in > the case of budget contention") we should no longer need the fix in > the SCSI code. Revert it, resolving conflicts with other patches that > have touched this code. > > With this revert (and the two new patches) I can run the script that > was in commit 7e70aa789d4a ("scsi: core: run queue if SCSI device > queue isn't ready and queue is idle") in a loop with no failure. If I > do this revert without the two new patches I can easily get a failure. > > Signed-off-by: Douglas Anderson > --- > I don't know for sure that we can revert this patch, but in the very > least the original test case now passes. If there is any question > about this, we can just drop this patch. I think it is safe to revert this patch. This patch should have been one workaround in case of dispatch from hctx->dispatch, since there is one race. When dispatch from scheduler queue, any IO completion will re-run all hctxs, so no need to do the trick. Reviewed-by: Ming Lei thanks, Ming