[Patch 05/12] Use wrapper routines around debug registers in processor related functions

K.Prasad
2009-05-13T16:14:45Z

[-- Attachment #1: modify_processor_related_05 --]
[-- Type: text/plain, Size: 3525 bytes --]

From: Alan Stern <stern@rowland.harvard.edu>

This patch enables the use of wrapper routines to access the debug/breakpoint
registers.

[K.Prasad: Split-out from the bigger patch and minor changes following
re-basing]

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
---
arch/x86/kernel/smpboot.c | 3 +++
arch/x86/power/cpu_32.c | 16 +++-------------
arch/x86/power/cpu_64.c | 15 +++------------
3 files changed, 9 insertions(+), 25 deletions(-)

Index: arch/x86/kernel/smpboot.c
===================================================================
--- arch/x86/kernel/smpboot.c.orig
+++ arch/x86/kernel/smpboot.c
@@ -63,6 +63,7 @@
#include <asm/apic.h>
#include <asm/setup.h>
#include <asm/uv/uv.h>
+#include <asm/debugreg.h>
#include <linux/mc146818rtc.h>

#include <asm/smpboot_hooks.h>
@@ -326,6 +327,7 @@ notrace static void __cpuinit start_seco
setup_secondary_clock();

wmb();
+ load_debug_registers();
cpu_idle();
}

@@ -1252,6 +1254,7 @@ void cpu_disable_common(void)
remove_cpu_from_maps(cpu);
unlock_vector_lock();
fixup_irqs();
+ hw_breakpoint_disable();
}

int native_cpu_disable(void)
Index: arch/x86/power/cpu_32.c
===================================================================
--- arch/x86/power/cpu_32.c.orig
+++ arch/x86/power/cpu_32.c
@@ -13,6 +13,7 @@
#include <asm/mce.h>
#include <asm/xcr.h>
#include <asm/suspend.h>
+#include <asm/debugreg.h>

static struct saved_context saved_context;

@@ -48,6 +49,7 @@ static void __save_processor_state(struc
ctxt->cr2 = read_cr2();
ctxt->cr3 = read_cr3();
ctxt->cr4 = read_cr4_safe();
+ hw_breakpoint_disable();
}

/* Needed by apm.c */
@@ -80,19 +82,7 @@ static void fix_processor_context(void)
load_TR_desc(); /* This does ltr */
load_LDT(&current->active_mm->context); /* This does lldt */

- /*
- * Now maybe reload the debug registers
- */
- if (current->thread.debugreg7) {
- set_debugreg(current->thread.debugreg0, 0);
- set_debugreg(current->thread.debugreg1, 1);
- set_debugreg(current->thread.debugreg2, 2);
- set_debugreg(current->thread.debugreg3, 3);
- /* no 4 and 5 */
- set_debugreg(current->thread.debugreg6, 6);
- set_debugreg(current->thread.debugreg7, 7);
- }
-
+ load_debug_registers();
}

static void __restore_processor_state(struct saved_context *ctxt)
Index: arch/x86/power/cpu_64.c
===================================================================
--- arch/x86/power/cpu_64.c.orig
+++ arch/x86/power/cpu_64.c
@@ -16,6 +16,7 @@
#include <asm/mtrr.h>
#include <asm/xcr.h>
#include <asm/suspend.h>
+#include <asm/debugreg.h>

static void fix_processor_context(void);

@@ -71,6 +72,7 @@ static void __save_processor_state(struc
ctxt->cr3 = read_cr3();
ctxt->cr4 = read_cr4();
ctxt->cr8 = read_cr8();
+ hw_breakpoint_disable();
}

void save_processor_state(void)
@@ -159,16 +161,5 @@ static void fix_processor_context(void)
load_TR_desc(); /* This does ltr */
load_LDT(&current->active_mm->context); /* This does lldt */

- /*
- * Now maybe reload the debug registers
- */
- if (current->thread.debugreg7){
- loaddebug(&current->thread, 0);
- loaddebug(&current->thread, 1);
- loaddebug(&current->thread, 2);
- loaddebug(&current->thread, 3);
- /* no 4 and 5 */
- loaddebug(&current->thread, 6);
- loaddebug(&current->thread, 7);
- }
+ load_debug_registers();
}