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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 BE38CC55186 for ; Thu, 23 Apr 2020 13:52:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9CE8F20728 for ; Thu, 23 Apr 2020 13:52:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="URkDANZ1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728636AbgDWNwJ (ORCPT ); Thu, 23 Apr 2020 09:52:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726926AbgDWNwI (ORCPT ); Thu, 23 Apr 2020 09:52:08 -0400 Received: from mail-il1-x141.google.com (mail-il1-x141.google.com [IPv6:2607:f8b0:4864:20::141]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 768DAC08ED7D for ; Thu, 23 Apr 2020 06:52:08 -0700 (PDT) Received: by mail-il1-x141.google.com with SMTP id e8so5567266ilm.7 for ; Thu, 23 Apr 2020 06:52:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=K0kiSpJdpt5NzjR2rc87lSUDGTW+J0mkXavjC7NX4h0=; b=URkDANZ18i7l8EMTaDnbsvv9CKA6pBNYrsSuVcozBJdAlFu+Fm88JzkvHTwro//ZXr s4VnlFHqww7tuoLrRodMANhPeZYIS3CaqJqrlssyMUUIeKf7badVaQEllGFc3uO/0ovb OgW4aNCG2x/2w2XaDfybOCC65I9HMeKWIYYMQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=K0kiSpJdpt5NzjR2rc87lSUDGTW+J0mkXavjC7NX4h0=; b=KzyF/vO/sihud1NSHVqBvFDorlsdiwxWZXMTeLuqbAWiPK3g/lcXp70NZGP/dXhDuF xBRW3SWD10XwH/CiLZXwCx6rYhYFTMtPuRG4/u2mdENrjpRuQ+c2PtNDNczYjI/Tb6+K dM8XkcS7bYW6MYNF5kQ/UCabCI4as8pJH9kR/yHdqhzM93LyPsKh+NxIIDp8qBZSxu3g cqgEgxb8MCsGTPK5omlsSSiV37+ZmXJ02HqnXnNuyzYmB6koni9WZNlbkfnykFiRJqLX SW2OgCms0YQaoGa9kwJ+EtY8GjADbWKCBpa4RILkNLsvsvMBXwVtSMEgqGghodCGjTv9 2Hkw== X-Gm-Message-State: AGi0PuYOZE6Bvnbil81D4rQLJsO1/5kfxPrgaB12hJvEvzAGN/d4jkwM Dl/rqKXEUTsRpck2scOyLtooWpldrGpA56YSrvgGbQ== X-Google-Smtp-Source: APiQypJE+c0suQ0XLykWP3NEC/rlj/rHRfrunXiI2/nKj47l8PHG5g0xmK+UP5b30nEX3sMv8Tw6exgnCYtYG1Q7RoI= X-Received: by 2002:a92:3509:: with SMTP id c9mr1052016ila.262.1587649927663; Thu, 23 Apr 2020 06:52:07 -0700 (PDT) MIME-Version: 1.0 References: <20200423044050.162093-1-joel@joelfernandes.org> <20200423114008.GB13910@bombadil.infradead.org> In-Reply-To: From: Joel Fernandes Date: Thu, 23 Apr 2020 09:51:56 -0400 Message-ID: Subject: Re: [RFC] fs: Use slab constructor to initialize conn objects in fsnotify To: Matthew Wilcox Cc: LKML , Amir Goldstein , Jan Kara , Linux FS Devel Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Apr 23, 2020 at 9:20 AM Joel Fernandes wrote: > > There's one improvement (although probably verys small) that the paper mentions: > Also according to the paper you referenced, the instruction cache is > what would also benefit. Those spinlock and hlist initialization > instructions wouldn't cost L1 I-cache footprint for every allocation. Just to add to my statement: Obviously, this benefit gives diminishing returns in this code path considering that the allocations here are infrequent. But I just mentioned it here for completeness sake. Thanks, - Joel