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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 44F91C64EB8 for ; Tue, 9 Oct 2018 11:22:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C77220835 for ; Tue, 9 Oct 2018 11:22:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=rasmusvillemoes.dk header.i=@rasmusvillemoes.dk header.b="jN+iAXVu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C77220835 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=rasmusvillemoes.dk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727873AbeJISjD (ORCPT ); Tue, 9 Oct 2018 14:39:03 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:35610 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726764AbeJISg7 (ORCPT ); Tue, 9 Oct 2018 14:36:59 -0400 Received: by mail-ed1-f68.google.com with SMTP id y19-v6so1330043edd.2 for ; Tue, 09 Oct 2018 04:20:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rasmusvillemoes.dk; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Tny/9sbwvLv3IhW/IiVhHLLmo7Yu5TP6WDbTE1LgMVI=; b=jN+iAXVuDivoH2d82mpmHS0ug5K6lJhCv7b1QwCVw1BOP6un8sYDha5CHZT3Xee8Hf 1q/BnuCwKHXOzh/BUzolt7pOR/VkMMan7v2vklYMeJC7Gt4s/+Xoz3002QM4DbCvNm9J OyGel4EbFlIFb+gataTyTi7Oy/Hl0LS4P/Vow= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Tny/9sbwvLv3IhW/IiVhHLLmo7Yu5TP6WDbTE1LgMVI=; b=JnPkKjtKF0ZUhEHOP+kK4yaVfZauvfckkt8v1yzGBb6e6EF0iAMZTeVAlZw/rsvMGb ChOvRsVV/EgH3CKYdd78+7modHhVGfFcU4RYa2RQhcVkmgradtaZg63KskYnokArHlIQ +BTAkN0mjYKcSZbTFjllZoXaPrTogv2fRnF4wWYZTzLwwftTAxUyiG/dNrVMrgeQ9ERm wT3aQFkOkovmSZlZq19oqRohzFRclZOJK5v/08SUfX59BdYTUUHZAnm7MfCtUmFGtH1Z VznlTCrbpNp41eLbvaU3kWT2xJbJb7AFe4RNrsHeshcipPMitoZRaHL1sk2RyCxSwygI u3tg== X-Gm-Message-State: ABuFfogrmrvY05P4tEE/t2VPVgRGfaFJUuemQDkX2Xco0t0EhtxncZ4B Am3uuw70d0p3rK6IDqYt2mzlEg== X-Google-Smtp-Source: ACcGV61CMo8JHf6RykIjMzsGN/qCUOTvQGrgPAxDx7Gvttym8sTD7TO8Bgl4IU/1sUOhXco9wyUvzQ== X-Received: by 2002:aa7:dc4b:: with SMTP id g11-v6mr34160817edu.115.1539084029230; Tue, 09 Oct 2018 04:20:29 -0700 (PDT) Received: from prevas-ravi.vestasvisitor.net ([193.47.71.171]) by smtp.gmail.com with ESMTPSA id n23-v6sm3595821eja.41.2018.10.09.04.20.28 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 09 Oct 2018 04:20:28 -0700 (PDT) From: Rasmus Villemoes To: Jason Baron , Andrew Morton Cc: linux-kernel@vger.kernel.org, Rasmus Villemoes Subject: [PATCH v2 09/23] dynamic_debug: use pointer comparison in ddebug_remove_module Date: Tue, 9 Oct 2018 13:19:59 +0200 Message-Id: <20181009112013.14238-10-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.19.1.4.g721af0fda3 In-Reply-To: <20181009112013.14238-1-linux@rasmusvillemoes.dk> References: <20180919220444.23190-1-linux@rasmusvillemoes.dk> <20181009112013.14238-1-linux@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that we store the passed-in string directly in ddebug_add_module, we can use pointer equality instead of strcmp. This is a little more efficient, but more importantly, this also makes the code somewhat more correct: Currently, if one loads and then unloads a module whose name happens to match the KBUILD_MODNAME of some built-in functionality (which need not even be modular at all), all of their dynamic debug entries vanish along with those of the actual module. For example, loading and unloading a core.ko hides all pr_debugs from drivers/base/core.c and other built-in files called core.c (incidentally, there is an in-tree module whose name is core, but I just tested this with an out-of-tree trivial one). Acked-by: Jason Baron Signed-off-by: Rasmus Villemoes --- lib/dynamic_debug.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 2155e0e23530..ab81155f928d 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -929,9 +929,10 @@ int ddebug_remove_module(const char *mod_name) mutex_lock(&ddebug_lock); list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) { - if (!strcmp(dt->mod_name, mod_name)) { + if (dt->mod_name == mod_name) { ddebug_table_free(dt); ret = 0; + break; } } mutex_unlock(&ddebug_lock); -- 2.19.1.3.g1d92a00e68