From patchwork Wed Jun 24 20:31:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11624253 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7110214E3 for ; Wed, 24 Jun 2020 20:34:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 58CC920899 for ; Wed, 24 Jun 2020 20:34:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="EWRzLy7u" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406492AbgFXUee (ORCPT ); Wed, 24 Jun 2020 16:34:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50548 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406462AbgFXUdN (ORCPT ); Wed, 24 Jun 2020 16:33:13 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A846C061795 for ; Wed, 24 Jun 2020 13:33:13 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id n11so3511192ybg.15 for ; Wed, 24 Jun 2020 13:33:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=RZTReFFMdjgTHNlONDHd9zt1v7eMyKbgxXLu5A5pzj0=; b=EWRzLy7ubn55a8LmKy3CDH4ngbdy7XK7KBx2ndgKQ/3d1qkgK3E2e2e0LoML9LtpAP te8DFa082g+gVIfEAqVPkw42n2K5N8oZDQPqI2EE+tN42iDW7P8u4zkwFKaeUaEIL3oq RsZa2tBkB8ErLDOh0+LYJEGFNduXUPYCZZp6PS5HSeXJMWIblGduZ6jmagNoIsWizsER wasijgerBJQ81R7rPMfgWDc43sju3PnN23fU0SKh+4T9fa3wRlwROOUy5biDfDpraPBM LfcrqPMgzOl+e9NbqEnHTOdpcfO4/PQ3tkVTmfAbrRs5+l+SSnKRsruNnEenHpqLqPiQ nuGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=RZTReFFMdjgTHNlONDHd9zt1v7eMyKbgxXLu5A5pzj0=; b=B2UZWDFEBB85y876yim+EcErS+uxE4v8MZV0A+cU8l128FVUFv8mEEZh97rtPF69vZ KgeSi48Zz/HuU2f/FTaKuQyTDhFJ4uxAuR5zosp8k91sbJtI6xFJmXOfuT9BdLW5SiP1 aRcoCCcbxwfq9G9s93BD5Yfw7OF0nUwvuCNTuZW2l5Uob32z5eMIR0J5POmXF24WUm56 GE34cOTEwb8oRLMlHCElrfve1LMqzKfwibyGZuItiGzOvLbItizrzfZQr2myGX9KJw9J YIsjww1q+iRwx3y9ttH8dtpHEV+Ogg3P61tV5d1fRUF0dqghGrJqwdgNPr6ozzibIZRQ fwdg== X-Gm-Message-State: AOAM533jW2crV0ZmmqnIVAa4rSxxA18/c6tgiQqC0TGsY7Xu3x+hNFSz ev8VVgPt4y+HawcqFFxltLBiFOK3yO3hRPEQLWI= X-Google-Smtp-Source: ABdhPJyU2t1AXfcgSNz/10D8PjugKl8rMw6I/kYhEGKclSW1I55A11LPtvbV37/K4/NXZ5XrSzlUdSrpZ+Ia6K6teRs= X-Received: by 2002:a25:4e0a:: with SMTP id c10mr44794280ybb.346.1593030792698; Wed, 24 Jun 2020 13:33:12 -0700 (PDT) Date: Wed, 24 Jun 2020 13:31:46 -0700 In-Reply-To: <20200624203200.78870-1-samitolvanen@google.com> Message-Id: <20200624203200.78870-9-samitolvanen@google.com> Mime-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> X-Mailer: git-send-email 2.27.0.212.ge8ba1cc988-goog Subject: [PATCH 08/22] kbuild: lto: remove duplicate dependencies from .mod files From: Sami Tolvanen To: Masahiro Yamada , Will Deacon Cc: Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With LTO, llvm-nm prints out symbols for each archive member separately, which results in a lot of duplicate dependencies in the .mod file when CONFIG_TRIM_UNUSED_SYMS is enabled. When a module consists of several compilation units, the output can exceed the default xargs command size limit and split the dependency list to multiple lines, which results in used symbols getting trimmed. This change removes duplicate dependencies, which will reduce the probability of this happening and makes .mod files smaller and easier to read. Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 82977350f5a6..82b465ce3ca0 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -291,7 +291,7 @@ endef # List module undefined symbols (or empty line if not enabled) ifdef CONFIG_TRIM_UNUSED_KSYMS -cmd_undef_syms = $(NM) $< | sed -n 's/^ *U //p' | xargs echo +cmd_undef_syms = $(NM) $< | sed -n 's/^ *U //p' | sort -u | xargs echo else cmd_undef_syms = echo endif