From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754433AbZBOKeH (ORCPT ); Sun, 15 Feb 2009 05:34:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751906AbZBOKdy (ORCPT ); Sun, 15 Feb 2009 05:33:54 -0500 Received: from e28smtp04.in.ibm.com ([59.145.155.4]:45029 "EHLO e28smtp04.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751885AbZBOKdx (ORCPT ); Sun, 15 Feb 2009 05:33:53 -0500 Date: Sun, 15 Feb 2009 16:03:44 +0530 From: "K.Prasad" To: Ingo Molnar Cc: Andrew Morton , Alan Stern , Roland McGrath , richardj_moore@uk.ibm.com, jason.wessel@windriver.com, Linux Kernel Mailing List Subject: [Patch 4/10] Introduce virtual debug register in thread_struct and wrapper-routines around process related functions Message-ID: <20090215103344.GE6855@in.ibm.com> Reply-To: prasad@linux.vnet.ibm.com References: <20090215103008.GA6855@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090215103008.GA6855@in.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce virtual debug register in thread_struct and wrapper-routines around process related functions From: Alan Stern This patch introduces virtual debug registers to used by the per-thread structure ad wrapper routines to manage debug registers by process-related functions. [K.Prasad: Split-out from the bigger patch and minor changes following re-basing] Signed-off-by: K.Prasad Signed-off-by: Alan Stern --- arch/x86/include/asm/debugreg.h | 27 +++++++++++++++++++++++++++ arch/x86/include/asm/processor.h | 10 +++------- 2 files changed, 30 insertions(+), 7 deletions(-) Index: linux-2.6-tip.hbkpt/arch/x86/include/asm/debugreg.h =================================================================== --- linux-2.6-tip.hbkpt.orig/arch/x86/include/asm/debugreg.h +++ linux-2.6-tip.hbkpt/arch/x86/include/asm/debugreg.h @@ -49,6 +49,8 @@ #define DR_LOCAL_ENABLE_SHIFT 0 /* Extra shift to the local enable bit */ #define DR_GLOBAL_ENABLE_SHIFT 1 /* Extra shift to the global enable bit */ +#define DR_LOCAL_ENABLE (0x1) /* Local enable for reg 0 */ +#define DR_GLOBAL_ENABLE (0x2) /* Global enable for reg 0 */ #define DR_ENABLE_SIZE 2 /* 2 enable bits per register */ #define DR_LOCAL_ENABLE_MASK (0x55) /* Set local bits for all 4 regs */ @@ -67,4 +69,29 @@ #define DR_LOCAL_SLOWDOWN (0x100) /* Local slow the pipeline */ #define DR_GLOBAL_SLOWDOWN (0x200) /* Global slow the pipeline */ +/* + * HW breakpoint additions + */ +#ifdef __KERNEL__ + +/* For process management */ +void flush_thread_hw_breakpoint(struct task_struct *tsk); +int copy_thread_hw_breakpoint(struct task_struct *tsk, + struct task_struct *child, unsigned long clone_flags); +void dump_thread_hw_breakpoint(struct task_struct *tsk, int u_debugreg[8]); +void switch_to_thread_hw_breakpoint(struct task_struct *tsk); + +/* For CPU management */ +void load_debug_registers(void); +static inline void disable_debug_registers(void) +{ + set_debugreg(0UL, 7); +} + +/* For use by ptrace */ +unsigned long thread_get_debugreg(struct task_struct *tsk, int n); +int thread_set_debugreg(struct task_struct *tsk, int n, unsigned long val); + +#endif /* __KERNEL__ */ + #endif /* _ASM_X86_DEBUGREG_H */ Index: linux-2.6-tip.hbkpt/arch/x86/include/asm/processor.h =================================================================== --- linux-2.6-tip.hbkpt.orig/arch/x86/include/asm/processor.h +++ linux-2.6-tip.hbkpt/arch/x86/include/asm/processor.h @@ -427,13 +427,9 @@ struct thread_struct { unsigned long ip; unsigned long fs; unsigned long gs; - /* Hardware debugging registers: */ - unsigned long debugreg0; - unsigned long debugreg1; - unsigned long debugreg2; - unsigned long debugreg3; - unsigned long debugreg6; - unsigned long debugreg7; + /* Hardware breakpoint info */ + unsigned long vdr6; + struct thread_hw_breakpoint *hw_breakpoint_info; /* Fault info: */ unsigned long cr2; unsigned long trap_no;