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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE051C433EF for ; Wed, 1 Jun 2022 08:38:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349312AbiFAIic (ORCPT ); Wed, 1 Jun 2022 04:38:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35456 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343797AbiFAIib (ORCPT ); Wed, 1 Jun 2022 04:38:31 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25A424D269; Wed, 1 Jun 2022 01:38:31 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id D14871F897; Wed, 1 Jun 2022 08:38:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1654072709; h=from:from:reply-to: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=6sRJx7dgkrP3lfQ1w9+FmL/xTk+6hJEOi+Q76uJOa+s=; b=gnq3y9WXYS1tb+Tz+KYQ6JTFI1uVEOhIwJDuBykhJIOGw1d2k6EiVq8J4FP/2dN7MCr8XD wlptnvtmfE0zmXxv0WTlzZ5war3KlL/HpjkNgZLMfmQ0XDw1ygOyi2+cCBfrHiIfLDdyPu B25E4US3VhWnjxoyVPz5EeWEJE+zWeY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1654072709; h=from:from:reply-to: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=6sRJx7dgkrP3lfQ1w9+FmL/xTk+6hJEOi+Q76uJOa+s=; b=zWAzszJYpDCB0DkfCK/db+u6SHB52Qys/480v4DJs75l1jjdlckXvxAmvT4dMM3nQIT5GF aSRFuveYLXQ6AZBw== Received: from quack3.suse.cz (unknown [10.163.28.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id C21862C141; Wed, 1 Jun 2022 08:38:29 +0000 (UTC) Received: by quack3.suse.cz (Postfix, from userid 1000) id 74833A0633; Wed, 1 Jun 2022 10:38:29 +0200 (CEST) Date: Wed, 1 Jun 2022 10:38:29 +0200 From: Jan Kara To: Yu Kuai Cc: paolo.valente@linaro.org, jack@suse.cz, axboe@kernel.dk, tj@kernel.org, linux-block@vger.kernel.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, yi.zhang@huawei.com Subject: Re: [PATCH -next v8 4/4] block, bfq: do not idle if only one group is activated Message-ID: <20220601083829.ywv4z5yfdmslcihv@quack3.lan> References: <20220531140858.3324294-1-yukuai3@huawei.com> <20220531140858.3324294-5-yukuai3@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220531140858.3324294-5-yukuai3@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue 31-05-22 22:08:58, Yu Kuai wrote: > Now that root group is counted into 'num_groups_with_pending_reqs', > 'num_groups_with_pending_reqs > 0' is always true in > bfq_asymmetric_scenario(). Thus change the condition to '> 1'. > > On the other hand, this change can enable concurrent sync io if only > one group is activated. > > Signed-off-by: Yu Kuai Looks good. Feel free to add: Reviewed-by: Jan Kara Just one language fixup below: > diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c > index 03b04892440c..d4aa8421968d 100644 > --- a/block/bfq-iosched.c > +++ b/block/bfq-iosched.c > @@ -820,7 +820,7 @@ bfq_pos_tree_add_move(struct bfq_data *bfqd, struct bfq_queue *bfqq) > * much easier to maintain the needed state: > * 1) all active queues have the same weight, > * 2) all active queues belong to the same I/O-priority class, > - * 3) there are no active groups. > + * 3) there are one active groups at most. ^^^ "there is at most one active group" Honza -- Jan Kara SUSE Labs, CR