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=-2.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 4C3F3C0651F for ; Thu, 4 Jul 2019 14:32:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20AD0218A3 for ; Thu, 4 Jul 2019 14:32:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="XA9XKA4y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727744AbfGDOc2 (ORCPT ); Thu, 4 Jul 2019 10:32:28 -0400 Received: from mail-ed1-f66.google.com ([209.85.208.66]:34038 "EHLO mail-ed1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727246AbfGDOc2 (ORCPT ); Thu, 4 Jul 2019 10:32:28 -0400 Received: by mail-ed1-f66.google.com with SMTP id s49so5643016edb.1; Thu, 04 Jul 2019 07:32:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=hG94lb2mfNpipyjyuBXQyz3ZoROecI4LdyTS4Vj1aUM=; b=XA9XKA4yi6IQLxDBOZSLzJDJ1P24RGWiALToGJfWjOvu6I+Lke7v4PE6vpt4zTO45f KiGPVmx1c1YtAzr2WZyJp0525y0uUiM0nG9LLRg6mxDNCw6Xjp57vDWhre5xVltjNySp f8Kfe+ewF1z6ILjMGeW6+dSFXbKC6OMpbRdbLLXxVMTBh5vM6N1C3hDZs5renLsWJYFu 9ZITRK7Bq4lRDxMwAHxLE18gAr8rESKdd5uHipVnCKM2I/iaZ66fShyrSwZuIKR2f0G4 eoPyMPB/TzopgZTTNzImjgnkfQ6OHld219zrdZGZLVZ0mATlt7Ix7UlE54yZgAgYouJV SU+A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=hG94lb2mfNpipyjyuBXQyz3ZoROecI4LdyTS4Vj1aUM=; b=B9yyrZbSuQ1ZVpOKBvXQCNTuG0TCNtLR6ykh7Hyx/EdwPc9E5rwbyEF8SrxWvWfS92 G8hNWhJITHoSvhnwMgR/hQOnotAgQCaSxVv8ViVpOsIXunj4Kqqwm07flLd8dxM71xeg 5OMsnQ9JtpJAqIAr9dkR2Xmfa6OwImL2rYYLXm7QlwQ7cKWWYVuy6U69Emv6H3ZkA6BH XQ8DCdtTrnPJD6kEmYIgdMBBiG5piHKeMD9Rgt5DcXfxaBRGBUQELw45Nt70FeyrWe+h h0/2HMKWYWgUXYFYaflOP9Rsup65E9N0tt8qybYQWvPGN3xe7XwwpPGOR1eHb7qmhAoW m5JQ== X-Gm-Message-State: APjAAAUpS5EqjbE+AXH71UjJZ0uIh6mLZFF1Y/G/19zokNwJRKAt72dY sy9BZ+duRdIpxaNw8aqQuFk+GeOu X-Google-Smtp-Source: APXvYqzT2XlfYr+uxPrC/zJOphkRAdeGPMcKImu0CzVFB9O9lFTTq1YMhHbw65sOeQXrNnJ2ydEjqA== X-Received: by 2002:a17:906:1f43:: with SMTP id d3mr29380618ejk.169.1562250745941; Thu, 04 Jul 2019 07:32:25 -0700 (PDT) Received: from [10.68.217.182] ([217.70.211.18]) by smtp.gmail.com with ESMTPSA id x10sm1708831edd.73.2019.07.04.07.32.24 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Thu, 04 Jul 2019 07:32:25 -0700 (PDT) Subject: Re: [PATCH] dax: Fix missed PMD wakeups To: Matthew Wilcox Cc: Dan Williams , linux-fsdevel , Jan Kara , stable , Robert Barror , Seema Pandit , linux-nvdimm , Linux Kernel Mailing List References: <156213869409.3910140.7715747316991468148.stgit@dwillia2-desk3.amr.corp.intel.com> <20190703121743.GH1729@bombadil.infradead.org> <20190703195302.GJ1729@bombadil.infradead.org> <20190704032728.GK1729@bombadil.infradead.org> <20190704135804.GL1729@bombadil.infradead.org> From: Boaz Harrosh Message-ID: Date: Thu, 4 Jul 2019 17:32:23 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20190704135804.GL1729@bombadil.infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-MW Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 04/07/2019 16:58, Matthew Wilcox wrote: > On Thu, Jul 04, 2019 at 04:00:00PM +0300, Boaz Harrosh wrote: <> >> Matthew you must be kidding an ilog2 in binary is zero clocks >> (Return the highest bit or something like that) > > You might want to actually check the documentation instead of just > making shit up. > Yes you are right I stand corrected. Must be smoking ;-) > https://www.agner.org/optimize/instruction_tables.pdf > > I think in this instance what we want is BSR (aka ffz) since the input is > going to be one of 0, 1, 3, 7, 15 or 31 (and we want 0, 1, 2, 3, 4, 5 as > results). > <> > The compiler doesn't know the range of 'sibs'. Unless we do the > profile-feedback thing. > Would you please consider the use of get_order() macro from #include Just for the sake of understanding? (Or at least a comment) Thanks Boaz