From patchwork Fri May 13 11:39:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 12848704 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 309AEC433EF for ; Fri, 13 May 2022 11:43:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379997AbiEMLnR (ORCPT ); Fri, 13 May 2022 07:43:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379963AbiEMLnL (ORCPT ); Fri, 13 May 2022 07:43:11 -0400 Received: from conuserg-07.nifty.com (conuserg-07.nifty.com [210.131.2.74]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7CDFD8081; Fri, 13 May 2022 04:42:32 -0700 (PDT) Received: from grover.sesame (133-32-177-133.west.xps.vectant.ne.jp [133.32.177.133]) (authenticated) by conuserg-07.nifty.com with ESMTP id 24DBeEwh008349; Fri, 13 May 2022 20:40:22 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-07.nifty.com 24DBeEwh008349 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1652442023; bh=OcOEuS6jEbLubdZRYm9mI6nzM08ugGxo0tuefY4hIgE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bp9jvRuF56C6r43GNXjG6BX+TvZHLTbdTLlR34dCXZg/oW32238SNreYsd6ecrnG6 PWr/NUZR0Fj64xkX3yxzCkcDwm8BUtpOQer8MUJE0kfUxAXrmqhHXhUVBDO1eaFvmZ Zd2DgWMNXGj/fTUiZ/fP4rrMZ0P/EShz6FzQ0fejjM7Fk5Mk+4x3zIAjw7LvNr3l8P 6RqksiC0umDQhSOQrTIO45Q7vzc3cdAd1y7uI/ao5m/kB6w/+AoM6bRZyfIpfL/JKy BLmQpIaa0h1Ej7NhYPC3vBgHWU9i3BlD07Dxm/NP3Kvu3JsIm6e+nmrjotY7EuCyv8 GgKFtSPjQ+KrA== X-Nifty-SrcIP: [133.32.177.133] From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Peter Zijlstra , linux-modules@vger.kernel.org, llvm@lists.linux.dev, Ard Biesheuvel , Sami Tolvanen , Masahiro Yamada Subject: [PATCH v6 08/10] kbuild: make *.mod rule robust against too long argument error Date: Fri, 13 May 2022 20:39:28 +0900 Message-Id: <20220513113930.10488-9-masahiroy@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220513113930.10488-1-masahiroy@kernel.org> References: <20220513113930.10488-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Like built-in.a, the command length of the *.mod rule scales with the depth of the directory times the number of objects in the Makefile. Add $(obj)/ by the shell command (awk) instead of by Make's builtin function. In-tree modules still have some room to the limit (ARG_MAX=2097152), but this is more future-proof for big modules in a deep directory. For example, you can build i915 as a module (CONFIG_DRM_I915=m) and compare drivers/gpu/drm/i915/.i915.mod.cmd with/without this commit. The issue is more critical for external modules because the M= path can be very long as Jeff Johnson reported before [1]. [1] https://lore.kernel.org/linux-kbuild/4c02050c4e95e4cb8cc04282695f8404@codeaurora.org/ Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier Tested-by: Nathan Chancellor --- (no changes since v2) Changes in v2: - New patch scripts/Makefile.build | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 8f1a355df7aa..f546b5f1f33f 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -270,8 +270,8 @@ $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE $(call if_changed_rule,cc_o_c) $(call cmd,force_checksrc) -cmd_mod = echo $(addprefix $(obj)/, $(call real-search, $*.o, .o, -objs -y -m)) | \ - $(AWK) -v RS='( |\n)' '!x[$$0]++' > $@ +cmd_mod = echo $(call real-search, $*.o, .o, -objs -y -m) | \ + $(AWK) -v RS='( |\n)' '!x[$$0]++ { print("$(obj)/"$$0) }' > $@ $(obj)/%.mod: FORCE $(call if_changed,mod)