Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757258AbXKYVz7 (ORCPT ); Sun, 25 Nov 2007 16:55:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755556AbXKYVzv (ORCPT ); Sun, 25 Nov 2007 16:55:51 -0500 Received: from mx1.redhat.com ([66.187.233.31]:53980 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755037AbXKYVzu (ORCPT ); Sun, 25 Nov 2007 16:55:50 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Andrew Morton , Linus Torvalds Cc: linux-kernel@vger.kernel.org X-Fcc: ~/Mail/linus Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Subject: [PATCH 01/27] ptrace: arch_has_single_step X-Shopping-List: (1) Mighty baskets (2) Noxious hobnobbing prescriptions (3) Constant selector commissions (4) Righteous nutrition Message-Id: <20071125215507.4B89226F8C5@magilla.localdomain> Date: Sun, 25 Nov 2007 13:55:07 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2749 Lines: 76 This defines the new macro arch_has_single_step() in linux/ptrace.h, a default for when asm/ptrace.h does not define it. It declares the new user_enable_single_step and user_disable_single_step functions. This is not used yet, but paves the way to harmonize on this interface for the arch-specific calls on all machines. Signed-off-by: Roland McGrath --- include/linux/ptrace.h | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 46 insertions(+), 0 deletions(-) diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index ae8146a..a6effc8 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -128,6 +128,52 @@ int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data); #define force_successful_syscall_return() do { } while (0) #endif +/* + * should define the following things inside #ifdef __KERNEL__. + * + * These do-nothing inlines are used when the arch does not + * implement single-step. The kerneldoc comments are here + * to document the interface for all arch definitions. + */ + +#ifndef arch_has_single_step +/** + * arch_has_single_step - does this CPU support user-mode single-step? + * + * If this is defined, then there must be function declarations or + * inlines for user_enable_single_step() and user_disable_single_step(). + * arch_has_single_step() should evaluate to nonzero iff the machine + * supports instruction single-step for user mode. + * It can be a constant or it can test a CPU feature bit. + */ +#define arch_has_single_step() (0) + +/** + * user_enable_single_step - single-step in user-mode task + * @task: either current or a task stopped in %TASK_TRACED + * + * This can only be called when arch_has_single_step() has returned nonzero. + * Set @task so that when it returns to user mode, it will trap after the + * next single instruction executes. + */ +static inline void user_enable_single_step(struct task_struct *task) +{ + BUG(); /* This can never be called. */ +} + +/** + * user_disable_single_step - cancel user-mode single-step + * @task: either current or a task stopped in %TASK_TRACED + * + * Clear @task of the effects of user_enable_single_step(). This can + * be called whether or not user_enable_single_step() was ever called + * on @task, and even if arch_has_single_step() returned zero. + */ +static inline void user_disable_single_step(struct task_struct *task) +{ +} +#endif /* arch_has_single_step */ + #endif #endif -- 1.5.3.4 - 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/