From patchwork Thu Jul 13 16:36:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jim Cromie X-Patchwork-Id: 13312493 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8B35EC001DD for ; Thu, 13 Jul 2023 16:37:55 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B8CA810E75B; Thu, 13 Jul 2023 16:37:09 +0000 (UTC) Received: from mail-il1-x12b.google.com (mail-il1-x12b.google.com [IPv6:2607:f8b0:4864:20::12b]) by gabe.freedesktop.org (Postfix) with ESMTPS id BE0EE10E763; Thu, 13 Jul 2023 16:37:04 +0000 (UTC) Received: by mail-il1-x12b.google.com with SMTP id e9e14a558f8ab-3461053677eso1987805ab.0; Thu, 13 Jul 2023 09:37:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1689266223; x=1691858223; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=xtXcwS8d/IDIwtZ853/2GI+9Fn3yNRgVoZNcTx+O3Ew=; b=HlYsuUhPgjpXCZ9henX1PDwU0cw3h2N3V5/vsfI3JqIAfhpOmkW+trSjYWT65U3nyC jLebmc9PX5LkHYZtGISPEwFqP511fRUaV3p126UUUQ12cEoisYsRB0Ai0IFMoK/o+Zno rGguAhVV1T0Xtt56BsYcD8yFiSs4AzNYqyvja+HjPwA8MdQrfo408bDsxt9OJHXJyZ3y NcJt4Mr3dq/irqiTKq+AH7wN/d04UujVFnf3InP9dyq90JzGLKhF4XgF3DEE6WUMuJvX hlybq+IReegFZ0TKYVW5nMEdCMyQ4uQvKHiCH6vc07xhaWaOnWfaVWviGizRleqeG3TT UVIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689266223; x=1691858223; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=xtXcwS8d/IDIwtZ853/2GI+9Fn3yNRgVoZNcTx+O3Ew=; b=FyJsAeMwCWA15s+i8GmABq62rfXCCrUi+5cMSiHu6WbDzcQA0QFs13cinll2lOcddZ VsCAUYp90vR1jkthb6wItesV62QypkegzYkMInKV6ZQSSLO+uEgVI/QifWe7hg79TxUJ 1LApAv6qpDvGXYmS5g0kNeBamoCcxZSjncMmBkgEaAz4bdLmBKPuD+gFLeeY51/xGRyD 4CwIHZto9FjqL9AfODfWjbGatZ9QRtb9xM4rQ1eYyKkKyo4QdbeiCEgnxAnqlXIWPyIq ghMktL690JXPhjGvphLEhX27ZO4erJmDKfuCDvFUMbUf9S65FI4TjIBFhd4NnJHLWyvJ 6MuQ== X-Gm-Message-State: ABy/qLbAi8e1Emk1Yz/pK33KQTsSeBECVZ6Fiplwame19ae/t0K5+qRJ ujzyAZ7tSh6rjxmvwZ7q1x8BV5rgqWj5sA== X-Google-Smtp-Source: APBJJlGKK8QkvWwdEzHjGRc5A1ATdY9Dfw8qrHFYEawb7ulcwGWCKqqAd0Mg8QH2SMEdwJLdP2dZ3w== X-Received: by 2002:a92:6c0f:0:b0:346:7fc:4fb8 with SMTP id h15-20020a926c0f000000b0034607fc4fb8mr122786ilc.1.1689266223658; Thu, 13 Jul 2023 09:37:03 -0700 (PDT) Received: from frodo.. (c-73-78-62-130.hsd1.co.comcast.net. [73.78.62.130]) by smtp.googlemail.com with ESMTPSA id s7-20020a92d907000000b00345950d7e94sm2147571iln.20.2023.07.13.09.37.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Jul 2023 09:37:03 -0700 (PDT) From: Jim Cromie To: jbaron@akamai.com, daniel.vetter@ffwll.ch, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Subject: [PATCH v4 18/21] compiler.h: RFC - s/__LINE__/__COUNTER__/ in __UNIQUE_ID fallback Date: Thu, 13 Jul 2023 10:36:23 -0600 Message-ID: <20230713163626.31338-19-jim.cromie@gmail.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230713163626.31338-1-jim.cromie@gmail.com> References: <20230713163626.31338-1-jim.cromie@gmail.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jani.nikula@intel.com, gregkh@linuxfoundation.org, llvm@lists.linux.dev, Nick Desaulniers , linux-sparse@vger.kernel.org, Nathan Chancellor , seanpaul@chromium.org, Luc Van Oostenryck , Tom Rix Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" We currently have 3 defns for __UNIQUE_ID(); gcc and clang are using __COUNTER__ for real uniqueness, 3rd just uses __LINE__, which should fail on this (and harder to avoid situations): DECLARE_FOO(); DECLARE_FOO(); Its 2023, can we haz a no-fallback __UNIQUE_ID ? NOTE: This also changes __UNIQUE_ID_ to _kaUID_. Ive been getting lkp-reports of collisions on names which should be unique; this shouldnt happen on gcc & clang, but does on some older ones, on some platforms, on some allyes & rand-configs. Like this: mips64-linux-ld: drivers/gpu/drm/display/drm_dp_helper.o:(__dyndbg_class_users+0x0): multiple definition of `__UNIQUE_ID_ddebug_class_user405'; drivers/gpu/drm/drm_gem_shmem_helper.o:(__dyndbg_class_users+0x0): first defined here Like above, the collision reports appear to always be 3-digit counters, which look like line-numbers. Changing to _kaUID_ in this defn should make it more obvious (in *.i file) when a fallback has happened. To be clear, I havent seen it yet. Nor have I seen the multiple-defn problem above since adding this patch. Lets see what lkp-robot says about this. CC: Luc Van Oostenryck (maintainer:SPARSE CHECKER) CC: Nathan Chancellor (supporter:CLANG/LLVM BUILD SUPPORT) CC: Nick Desaulniers (supporter:CLANG/LLVM BUILD SUPPORT) CC: Tom Rix (reviewer:CLANG/LLVM BUILD SUPPORT) CC: linux-sparse@vger.kernel.org (open list:SPARSE CHECKER) CC: linux-kernel@vger.kernel.org (open list) CC: llvm@lists.linux.dev (open list:CLANG/LLVM BUILD SUPPORT) Signed-off-by: Jim Cromie --- include/linux/compiler.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index d7779a18b24f..677d6c47cd9e 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -177,9 +177,9 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, __asm__ ("" : "=r" (var) : "0" (var)) #endif -/* Not-quite-unique ID. */ +/* JFTI: to fix Not-quite-unique ID */ #ifndef __UNIQUE_ID -# define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __LINE__) +# define __UNIQUE_ID(prefix) __PASTE(__PASTE(_kaUID_, prefix), __COUNTER__) #endif /**