Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753009AbaGLOoV (ORCPT ); Sat, 12 Jul 2014 10:44:21 -0400 Received: from mail-we0-f176.google.com ([74.125.82.176]:38865 "EHLO mail-we0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752536AbaGLOoP (ORCPT ); Sat, 12 Jul 2014 10:44:15 -0400 From: Mathias Krause To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: Joe Perches , Rasmus Villemoes , Andrew Morton , linux-kernel@vger.kernel.org, Mathias Krause Subject: [PATCH v2 1/8] init.h: Add __init_str / __exit_str macros Date: Sat, 12 Jul 2014 16:43:25 +0200 Message-Id: <1405176212-12175-2-git-send-email-minipli@googlemail.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1405176212-12175-1-git-send-email-minipli@googlemail.com> References: <1405176212-12175-1-git-send-email-minipli@googlemail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add macros to be able to mark string literals used in __init / __exit functions. Signed-off-by: Mathias Krause --- v2: - use a better code example --- include/linux/init.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/include/linux/init.h b/include/linux/init.h index 2df8e8dd10..2c1cf10bb7 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -35,6 +35,20 @@ * Don't forget to initialize data not at file scope, i.e. within a function, * as gcc otherwise puts the data into the bss section and not into the init * section. + * + * For strings used in __init / __exit functions the __init_str() / + * __exit_str() macros will take care of marking the strings accordingly so + * they can be freed, too. Otherwise the strings would resist in memory, even + * though they are no longer referenced. + * + * Use them like this: + * + * static int __init my_setup(char *arg) + * { + * if (!strcmp(arg, __init_str("disable"))) + * enabled = false; + * } + * __setup("mydev=", my_setup); */ /* These are for everybody (although not all archs will actually @@ -45,6 +59,12 @@ #define __exitdata __section(.exit.data) #define __exit_call __used __section(.exitcall.exit) +/* Those can be used to mark strings used in __init / __exit functions. */ +#define __init_str(str) __mark_str(str, __UNIQUE_ID(_init_str_), __initconst) +#define __exit_str(str) __mark_str(str, __UNIQUE_ID(_exit_str_), __exitdata) +#define __mark_str(str, var, __section) \ + ({ static const char var[] __section __aligned(1) = str; var; }) + /* * Some architecture have tool chains which do not handle rodata attributes * correctly. For those disable special sections for const, so that other -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/