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=-11.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 17D10C4363C for ; Thu, 1 Apr 2021 17:51:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E88876112E for ; Thu, 1 Apr 2021 17:51:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234556AbhDARvv (ORCPT ); Thu, 1 Apr 2021 13:51:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:48902 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236330AbhDARsA (ORCPT ); Thu, 1 Apr 2021 13:48:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8D6A7611CB; Thu, 1 Apr 2021 12:59:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617281962; bh=QFBvSxpFBe+JRLuZOO99kIhfEMTprfAcsBarAbnDeB4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AaizDmKnP+8Q4qYSu0tQ8ujlblwti05LFGjCWGhiRTuK+AYogq5z1pOMOsZJrr+tG RYUKsyFsylCUs0z+9eSvZAhsrXccM8ZDaYQxgyKocKxJJj7HjB0kg24bPJMcfy2Y59 xjMI1ppE05HQYRetrSrBNwXMgVSI8/rDhdIbGx9yRKYzygrvIcHmf9N2aGcYPhfQkZ UKxTbvPA15PzL5VoRjkBcUomSlyO7RUTKF7QspBiFMTGJOt1MU1k/1ACQ1v7R0fJNV 5GSSlf6tKAYcHBD3YyA7eXaX5H9FE7obzEBaxRO9gLllY5e92vj4b0L/IXOJn4Ixhv C0BUUmqG4mf1g== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id DF52940647; Thu, 1 Apr 2021 09:59:19 -0300 (-03) Date: Thu, 1 Apr 2021 09:59:19 -0300 From: Arnaldo Carvalho de Melo To: Yonghong Song Cc: Arnaldo Carvalho de Melo , dwarves@vger.kernel.org, Alexei Starovoitov , Andrii Nakryiko , Bill Wendling , bpf@vger.kernel.org, David Blaikie , =?utf-8?B?RsSBbmctcnXDrCBTw7JuZw==?= , kernel-team@fb.com, Nick Desaulniers Subject: Re: [PATCH dwarves 0/2] dwarf_loader: improve cus__merging_cu() Message-ID: References: <20210401025815.2254256-1-yhs@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210401025815.2254256-1-yhs@fb.com> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Em Wed, Mar 31, 2021 at 07:58:15PM -0700, Yonghong Song escreveu: > Function cus__merging_cu() is introduced in Commit 39227909db3c > ("dwarf_loader: Permit merging all DWARF CU's for clang LTO built > binary") to test whether cross-cu references may happen. > The original implementation anticipates compilation flags > in dwarf, but later some concerns about binary size surfaced > and the decision is to scan .debug_abbrev as a faster way > to check cross-cu references. Also putting a note in vmlinux > to indicate whether lto is enabled for built or not can > provide a much faster way. Great work! Reviewing/testing right now. - Arnaldo > This patch set implemented this two approaches, first > checking the note (in Patch #2), if not found, then > check .debug_abbrev (in Patch #1). > > Yonghong Song (2): > dwarf_loader: check .debug_abbrev for cross-cu references > dwarf_loader: check .notes section for lto build info > > dwarf_loader.c | 76 ++++++++++++++++++++++++++++++++++++-------------- > 1 file changed, 55 insertions(+), 21 deletions(-) > > -- > 2.30.2 > -- - Arnaldo