From patchwork Sat Jul 9 10:56:55 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tixy X-Patchwork-Id: 959782 Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p69ExrRj017466 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sat, 9 Jul 2011 15:00:14 GMT Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QfVb0-0005ir-9t; Sat, 09 Jul 2011 11:21:14 +0000 Received: from localhost ([127.0.0.1] helo=canuck.infradead.org) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QfVNY-00071K-7H; Sat, 09 Jul 2011 11:07:20 +0000 Received: from smarthost03.mail.zen.net.uk ([212.23.3.142]) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QfVEO-0004KQ-Cc for linux-arm-kernel@lists.infradead.org; Sat, 09 Jul 2011 10:58:06 +0000 Received: from [82.69.122.217] (helo=plug1) by smarthost03.mail.zen.net.uk with esmtpsa (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.63) (envelope-from ) id 1QfVEM-0005de-Fd for linux-arm-kernel@lists.infradead.org; Sat, 09 Jul 2011 10:57:50 +0000 Received: from [192.168.2.20] (helo=computer2) by plug1 with esmtp (Exim 4.72) (envelope-from ) id 1QfVEL-0003ge-56 for linux-arm-kernel@lists.infradead.org; Sat, 09 Jul 2011 11:57:49 +0100 Received: from tixy by computer2 with local (Exim 4.72) (envelope-from ) id 1QfVEL-0005TT-1r for linux-arm-kernel@lists.infradead.org; Sat, 09 Jul 2011 11:57:49 +0100 From: Tixy To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 08/51] ARM: kprobes: Make str_pc_offset a constant on ARMv7 Date: Sat, 9 Jul 2011 11:56:55 +0100 Message-Id: <1310209058-20980-9-git-send-email-tixy@yxit.co.uk> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1310209058-20980-1-git-send-email-tixy@yxit.co.uk> References: <1310209058-20980-1-git-send-email-tixy@yxit.co.uk> X-Originating-Smarthost03-IP: [82.69.122.217] X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.6 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20110709_065753_136247_05F2D66E X-CRM114-Status: GOOD ( 16.45 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.3.1 on canuck.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [212.23.3.142 listed in list.dnswl.org] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Sat, 09 Jul 2011 15:00:14 +0000 (UTC) From: Jon Medhurst The str_pc_offset value is architecturally defined on ARMv7 onwards so we can make it a compile time constant. This means on Thumb kernels the runtime checking code isn't needed, which saves us from having to fix it to work for Thumb. Signed-off-by: Jon Medhurst --- arch/arm/kernel/kprobes.h | 14 ++++++++++++++ arch/arm/kernel/kprobes-common.c | 4 ++++ 2 files changed, 18 insertions(+), 0 deletions(-) diff --git a/arch/arm/kernel/kprobes.h b/arch/arm/kernel/kprobes.h index 43f630d..406bb2d 100644 --- a/arch/arm/kernel/kprobes.h +++ b/arch/arm/kernel/kprobes.h @@ -36,7 +36,21 @@ void __init arm_kprobe_decode_init(void); extern kprobe_check_cc * const kprobe_condition_checks[16]; + +#if __LINUX_ARM_ARCH__ >= 7 + +/* str_pc_offset is architecturally defined from ARMv7 onwards */ +#define str_pc_offset 8 +#define find_str_pc_offset() + +#else /* __LINUX_ARM_ARCH__ < 7 */ + +/* We need a run-time check to determine str_pc_offset */ extern int str_pc_offset; +void __init find_str_pc_offset(void); + +#endif + /* * Test if load/store instructions writeback the address register. diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c index e18576c..87e91ce 100644 --- a/arch/arm/kernel/kprobes-common.c +++ b/arch/arm/kernel/kprobes-common.c @@ -17,6 +17,8 @@ #include "kprobes.h" +#ifndef find_str_pc_offset + /* * For STR and STM instructions, an ARM core may choose to use either * a +8 or a +12 displacement from the current instruction's address. @@ -40,6 +42,8 @@ void __init find_str_pc_offset(void) str_pc_offset = ret; } +#endif /* !find_str_pc_offset */ + void __init arm_kprobe_decode_init(void) {