Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759681Ab1D0RBq (ORCPT ); Wed, 27 Apr 2011 13:01:46 -0400 Received: from mail-ww0-f44.google.com ([74.125.82.44]:43730 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759369Ab1D0RAN (ORCPT ); Wed, 27 Apr 2011 13:00:13 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=llwLQxIgZQ5eSs0yYfrDUVdPZzvee1om8uOePK+T0OvVv+1MX4zMliBkpM7KNn7uo+ Buv5d/nsb7ijpLsx/EAXx1u5G5hNnQGZuq2TzAMbMvlysC1MQu/48C0NF1c5SxrIX8PR gV/bAQvSO6TEIWQGTlpFeWQMbQ3Ih+HL9AgbE= From: Frederic Weisbecker To: LKML Cc: LKML , Frederic Weisbecker , Ingo Molnar , Peter Zijlstra , Will Deacon , Prasad , Paul Mundt Subject: [PATCH 1/6] hw_breakpoints: Split hardware breakpoints config Date: Wed, 27 Apr 2011 18:59:57 +0200 Message-Id: <1303923602-2923-2-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.7.3.2 In-Reply-To: <1303923602-2923-1-git-send-email-fweisbec@gmail.com> References: <1303923602-2923-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2937 Lines: 84 The hardware breakpoint config is only made of an ability. An arch that support this feature selects HAVE_HW_BREAKPOINT. If so, the feature is definetly built-in, the user can't decide to turn it off. As hw_breakpoints depend on perf, it also makes perf a mandatory feature. The whole is quite a piece of code and may not be desired on some embedded systems. In order to prepare to make this optable by the user, split the config into the more traditional couple (ability, user choice) by providing a new HW_BREAKPOINT config. It is default on and depends on CONFIG_EXPERT because breakpoint ptrace requests are part of the usual user ABI. The user must know what he's doing before turning that off. For now, only the archs that already implemented a conditional HAVE_HW_BREAKPOINT can turn off HW_BREAKPOINT. x86 and sh have it always selected because they need more background work to support this new modularity. Signed-off-by: Frederic Weisbecker Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Will Deacon Cc: Prasad Cc: Paul Mundt --- arch/sh/Kconfig | 1 + arch/x86/Kconfig | 1 + init/Kconfig | 10 ++++++++++ 3 files changed, 12 insertions(+), 0 deletions(-) diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index 4b89da2..0d4d124 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -44,6 +44,7 @@ config SUPERH32 select HAVE_FUNCTION_GRAPH_TRACER select HAVE_ARCH_KGDB select HAVE_HW_BREAKPOINT + select HW_BREAKPOINT select HAVE_MIXED_BREAKPOINTS_REGS select PERF_EVENTS select ARCH_HIBERNATION_POSSIBLE if MMU diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index cc6c53a..8b49bff 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -54,6 +54,7 @@ config X86 select HAVE_KERNEL_XZ select HAVE_KERNEL_LZO select HAVE_HW_BREAKPOINT + select HW_BREAKPOINT select HAVE_MIXED_BREAKPOINTS_REGS select PERF_EVENTS select HAVE_PERF_EVENTS_NMI diff --git a/init/Kconfig b/init/Kconfig index 56240e7..51f587f 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -924,6 +924,16 @@ menuconfig EXPERT environments which can tolerate a "non-standard" kernel. Only use this if you really know what you are doing. +config HW_BREAKPOINT + bool "Hardware breakpoints" if EXPERT + depends on HAVE_HW_BREAKPOINT + default y + help + Hardware breakpoints are a feature implemented by most CPUs + to trigger an event when an instruction or data fetch + matches a given pattern. This is typically used by ptrace + and perf events. + config EMBEDDED bool "Embedded system" select EXPERT -- 1.7.3.2 -- 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/