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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 5D429C433E0 for ; Wed, 24 Jun 2020 23:39:20 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 255FB20738 for ; Wed, 24 Jun 2020 23:39:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="efWxPuz7"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="ghe0LNHZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 255FB20738 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=wXel4bvnZ5OfmR6vQWdt5xnikltfjIweMz+5hLqKaKw=; b=efWxPuz7Q6RiUPSfysUy3b2jt RZpfkhracNnwMldvg2VUTniRguH9hTXLb7ylwTQxzPz8hGPVtyjxo6GFYFYFYwN9z4tzCQNFK4Z5O 9yW1CT4L7256WYEaBOdTGVWM4DaEeme+3IpvvBZyFoBRDWT9R6/OtH1ngMMDENdMwLPbFD33gyP3g ExAqbs4QMIl/jWRojeBw95B9bmZYwpi9eYViLGAzpGFS3eF99w7XHn1PQCykb4gOeGmsZ87PnByV/ aqAY/Pxd2TvYZS1aJkvZXv3pMGa870L1jhLUD8sl26/qle+luwcTowJLxFZW6rSGVOgPaDoca7CjA IM5MkuTnQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1joExV-0002eJ-Fr; Wed, 24 Jun 2020 23:37:37 +0000 Received: from mail-pl1-x642.google.com ([2607:f8b0:4864:20::642]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1joExS-0002bd-0M for linux-arm-kernel@lists.infradead.org; Wed, 24 Jun 2020 23:37:34 +0000 Received: by mail-pl1-x642.google.com with SMTP id n2so1840325pld.13 for ; Wed, 24 Jun 2020 16:37:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=mo7Dwe07kJhP63QLmOzciNFvW218NBaVIlEPp4HbWlg=; b=ghe0LNHZStIXrutzWngNn1w8HnVKxzkKAANg+f3UNbpWa1VXDLTQLRRUxQiw0ETxf1 8IwO0ripMH+IKCR86WNY+ysG11jZ8MVO51xum9mEa475UtB+fdRpajYIKrof1LeRnhfw q/KZy9ALnBT7rcr/zSWyqYTnZ3OeY5pBxENZEDhKneGeIxS3jxNDb3T6z60V1Qc+Vdy6 OTaykXWX6WKsBL92+Zu8AYSrqkunkoROSncALDdIHd5jRSMEYzkTx2v4nRNz4Z77j4S9 tRCzT7qVWnXl4XZ9bSsfQVqiYUdUQyfJWFL+rlMfK7ACBBFVz6umkgQZxUMxIfkAgDuf rFfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=mo7Dwe07kJhP63QLmOzciNFvW218NBaVIlEPp4HbWlg=; b=glBSXJh1hi+uso8tp8YYU4D+KdIlnWpkwJhjB25YVVJueqjZ24NQ2aDOahCupe9ZQc ZtxnxyfV9jcHTMhaK92l7n/dKBghFmgv4jabDqDE34IuQwF7IFoRq5mQ81y0Iy3YBze4 8Tq4RgzAPNetGzcN7pOq2Fsl/7eHpr8Sp1kdT0hAKkcNF6r0SciRr8r3RfBjv35o1GEc Pks7YtpCHWS8g2M5TIys8WrndaZm8B61Dqfca/RlEqwWy4UR9hmbJNO98WaV89WAwKVX XRFoysadb+l+QMKJ/Tut4b6tW7B/33c6Gs1HOcOcPSpYzRs/FwCsDY2Cednbno+NoX2g 49FQ== X-Gm-Message-State: AOAM532/0pmD9w/y/HaccDzaBC1t1KD1D+LQcFbJ+cNeaGxqDSzOrzrq MP1PtytEQj7XD6565HAcO0xb6g== X-Google-Smtp-Source: ABdhPJzbL+A8YRu6cQqMhEnH4JVMHPuZevDUkJdMyUg1rfNtOurVArWJG2BoYxI9g7/QXZLvtzZHnQ== X-Received: by 2002:a17:90a:9d8b:: with SMTP id k11mr267919pjp.10.1593041850610; Wed, 24 Jun 2020 16:37:30 -0700 (PDT) Received: from google.com ([2620:15c:201:2:ce90:ab18:83b0:619]) by smtp.gmail.com with ESMTPSA id c9sm21338811pfr.72.2020.06.24.16.37.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Jun 2020 16:37:29 -0700 (PDT) Date: Wed, 24 Jun 2020 16:37:24 -0700 From: Sami Tolvanen To: Peter Zijlstra Subject: Re: [PATCH 06/22] kbuild: lto: limit inlining Message-ID: <20200624233724.GA94769@google.com> References: <20200624203200.78870-1-samitolvanen@google.com> <20200624203200.78870-7-samitolvanen@google.com> <20200624212055.GU4817@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200624212055.GU4817@hirez.programming.kicks-ass.net> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, x86@kernel.org, Kees Cook , "Paul E. McKenney" , kernel-hardening@lists.openwall.com, Greg Kroah-Hartman , Masahiro Yamada , linux-kbuild@vger.kernel.org, Nick Desaulniers , linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, George Burgess IV , linux-pci@vger.kernel.org, Will Deacon , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 24, 2020 at 11:20:55PM +0200, Peter Zijlstra wrote: > On Wed, Jun 24, 2020 at 01:31:44PM -0700, Sami Tolvanen wrote: > > This change limits function inlining across translation unit > > boundaries in order to reduce the binary size with LTO. > > > > The -import-instr-limit flag defines a size limit, as the number > > of LLVM IR instructions, for importing functions from other TUs. > > The default value is 100, and decreasing it to 5 reduces the size > > of a stripped arm64 defconfig vmlinux by 11%. > > Is that also the right number for x86? What about the effect on > performance? What did 6 do? or 4? This is the size limit we decided on for Android after testing on arm64, but the number is obviously a compromise between code size and performance. I'd be happy to benchmark this further once other concerns have been resolved. Sami _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel