hw-breakpoints: use wrapper routines around debug registers in processor related...

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

The hardcoded debug registers save and restore operations for threads
breakpoints are replaced by wrappers.

And now that we handle the kernel breakpoints too, we also need to handle them
on cpu hotplug operations.

[ Impact: adapt new hardware breakpoint api to cpu hotplug ]

Original-patch-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 58d24ef917d8b46e7c7faedc4dd3fc79266ad0cb..2b2652d205c0ed2a58725c7adcd87e8cdef929c4 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/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_secondary(void *unused)
        setup_secondary_clock();
 
        wmb();
+       load_debug_registers();
        cpu_idle();
 }
 
@@ -1250,6 +1252,7 @@ void cpu_disable_common(void)
        remove_cpu_from_maps(cpu);
        unlock_vector_lock();
        fixup_irqs();
+       hw_breakpoint_disable();
 }
 
 int native_cpu_disable(void)

diff --git a/arch/x86/power/cpu_32.c b/arch/x86/power/cpu_32.c
index 5199139480036f09098eecd37268010e954e452e..2bc3b016de90ee7ec595543f91ec2d047f0bee33 100644 (file)
--- a/arch/x86/power/cpu_32.c
+++ b/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(struct saved_context *ctxt)
        ctxt->cr2 = read_cr2();
        ctxt->cr3 = read_cr3();
        ctxt->cr4 = read_cr4_safe();
+       hw_breakpoint_disable();
 }
 
 /* Needed by apm.c */
@@ -83,16 +85,7 @@ static void fix_processor_context(void)
        /*
         * Now maybe reload the debug registers
         */
-       if (current->thread.debugreg7) {
-               set_debugreg(current->thread.debugreg[0], 0);
-               set_debugreg(current->thread.debugreg[1], 1);
-               set_debugreg(current->thread.debugreg[2], 2);
-               set_debugreg(current->thread.debugreg[3], 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)

diff --git a/arch/x86/power/cpu_64.c b/arch/x86/power/cpu_64.c
index 1e3bdcc959ffdfbf08cb9e86717eba13835c1f29..46866a13a93acac5e4db22228855f93b6c975caf 100644 (file)
--- a/arch/x86/power/cpu_64.c
+++ b/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(struct saved_context *ctxt)
        ctxt->cr3 = read_cr3();
        ctxt->cr4 = read_cr4();
        ctxt->cr8 = read_cr8();
+       hw_breakpoint_disable();
 }
 
 void save_processor_state(void)
@@ -162,13 +164,5 @@ static void fix_processor_context(void)
        /*
         * Now maybe reload the debug registers
         */
-       if (current->thread.debugreg7){
-               set_debugreg(current->thread.debugreg[0], 0);
-               set_debugreg(current->thread.debugreg[1], 1);
-               set_debugreg(current->thread.debugreg[2], 2);
-               set_debugreg(current->thread.debugreg[3], 3);
-                /* no 4 and 5 */
-                loaddebug(&current->thread, 6);
-                loaddebug(&current->thread, 7);
-       }
+       load_debug_registers();
 }