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 1E37AC4332F for ; Wed, 23 Nov 2022 18:32:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239692AbiKWSc4 (ORCPT ); Wed, 23 Nov 2022 13:32:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60198 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239856AbiKWScE (ORCPT ); Wed, 23 Nov 2022 13:32:04 -0500 Received: from mail-pg1-x52a.google.com (mail-pg1-x52a.google.com [IPv6:2607:f8b0:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 987FA58BCB; Wed, 23 Nov 2022 10:31:57 -0800 (PST) Received: by mail-pg1-x52a.google.com with SMTP id q1so17448156pgl.11; Wed, 23 Nov 2022 10:31:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=0WaeNxRFAhW4+njSz3oymHAfGYjiGBjYSgTnlxkSAys=; b=jxxUgRm3rae626X/F21Ixmc+goaczD8yETEXBu7QKc5qDMcofymNGMqTIMRVMFSRgo MWh0pdG+HtHw/CoioHszw6hAOBoiZlBfcQaWru3S0hQoUOw0a150L6bPjTztvDXr6EHd LQHcc7w27lcEfmNURWK2YGbv5ooe00NXtY9/nHbuKrqPlRfT6GjcjDNIZQx7wHCcEeiK uFNz1BwW7Y/3JL5VqEoKKeLWI94+tneUv4fB0k9afElk693ZB3qerfUL+jP+GlR6/LAb AmqWawnah09OIwkxNg3OtH5d6XnCCa5Bp02R8mdnjDRzhKp8PWkO5lPULhVQTq8eJzxB cxdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0WaeNxRFAhW4+njSz3oymHAfGYjiGBjYSgTnlxkSAys=; b=qV2I9ZlBNcgVh7XNmZiRe0zt/KYqIWQ9WWH9Pl+LayIF0oQxeaZTiDAiMGOxo+rtr7 jJHLwPJKcP5lRMx8OT0bXhZzTsLc43sVq0QvLKluoTEf7ErlDBNMlrFlQ9j1gSUJocmV sikYP5NpOkQh84zYGUIN8jH/PORcFP6L6LA/pjhN2DDiLezFPOr8ASioCNHJ4ABviY84 8sjPJZMgbZ5Bg9absx0s2oRwQQ3aFcISFl4dzkGyF7nWpKhRnEkFf6ATPO+B49SFbzZr eNwDLWoiTaDv+U6G3rSLuvb4+jD7JXhMlSjvTAQf08c43GVaVNMhTPE3gYRh6Yvt6BJ9 f95A== X-Gm-Message-State: ANoB5pkXIx9p8hjO0tOvgHsRgnzsopvNf/iiVXF4uG/9qcJKfW8S/Sms TPGxP71G7V8nX8VSfy9EkiM= X-Google-Smtp-Source: AA0mqf6FUu+yUZDk/M5N06NEv5Vf/o2Bx8fJlwotaqECXvlaAArqcZacDD1GVmK05av44gGaKR8KTQ== X-Received: by 2002:aa7:810e:0:b0:56b:f23a:7854 with SMTP id b14-20020aa7810e000000b0056bf23a7854mr14683565pfi.66.1669228316945; Wed, 23 Nov 2022 10:31:56 -0800 (PST) Received: from localhost (2603-800c-1a02-1bae-a7fa-157f-969a-4cde.res6.spectrum.com. [2603:800c:1a02:1bae:a7fa:157f:969a:4cde]) by smtp.gmail.com with ESMTPSA id b1-20020a17090ae38100b002132f3e71c6sm1699262pjz.52.2022.11.23.10.31.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Nov 2022 10:31:56 -0800 (PST) Sender: Tejun Heo Date: Wed, 23 Nov 2022 08:31:55 -1000 From: Tejun Heo To: Kemeng Shi Cc: josef@toxicpanda.com, axboe@kernel.dk, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/11] blk-throttle: remove unnecessary check for validation of limit index Message-ID: References: <20221123060401.20392-1-shikemeng@huawei.com> <20221123060401.20392-10-shikemeng@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221123060401.20392-10-shikemeng@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 23, 2022 at 02:03:59PM +0800, Kemeng Shi wrote: > We always keep limit index valid as following: > Max limit is always valid and low limit can only be invalidated in > blk_throtl_update_limit_valid. Each time low limit may become invalid > after blk_throtl_update_limit_valid is called, we will check and make > sure current limit index is valid. > > It's reasonable to always keep limit index valid, so we can remove this > check. It's not obvious to me that it's correct and I'm not sure what we're gaining by removing this while risking subtle breakages. -- tejun