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[23.128.96.18]) by mx.google.com with ESMTP id do17si1418929ejc.266.2020.04.23.06.56.37; Thu, 23 Apr 2020 06:57:02 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@joelfernandes.org header.s=google header.b=URkDANZ1; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728639AbgDWNwJ (ORCPT + 99 others); Thu, 23 Apr 2020 09:52:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728613AbgDWNwI (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 71591C08E934 for ; Thu, 23 Apr 2020 06:52:08 -0700 (PDT) Received: by mail-il1-x141.google.com with SMTP id q10so5598299ile.0 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=dL+W5bx0EgnSnooFufSbAnl48k6IHCvnJM/ikNzNVHkCCtusRSE7EDlOKxeF4u41lP CV42r8bH6cqhnzXQUPspUbHskWoy87uIDfuMhwF4B3ldDun8JJ2k2GSt5Zlj+yvsLAaU MwZnk4Bi4r8LMURzt+yWZfTlRU+6w8CGT/ntsgQ5dlg7czlkg0hjeypYU6oQ5+g186T2 QjxiQv6mD3wt6d5ey+jFsw/smeL3hE2j8r20qS5PTE0ntBjujSEoF9n6LS+j3+ng6IHO Z9tvGsZ7ConswxqHNFTRtXg9omC3KxDvdkoUlkpMiPi5UkajjEZjeHl4WcMuJK4/IR14 45Jw== X-Gm-Message-State: AGi0PubLGWE8ClC1iNTMZfO5RJXDbrACJUt6ozaC4KUp86p3BTQNAeQU GAeW3BgmOC86ekQl8yqVBQWeEyjrLnQDPK8p1+LblO1N 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-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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