vserver 1.9.5.x5

[linux-2.6.git] / arch / ppc / kernel / entry.S

diff --git a/arch/ppc/kernel/entry.S b/arch/ppc/kernel/entry.S
index 91318c1..08083be 100644 (file)
--- a/arch/ppc/kernel/entry.S
+++ b/arch/ppc/kernel/entry.S
@@ -111,8 +111,10 @@ transfer_to_handler:
        addi    r11,r1,STACK_FRAME_OVERHEAD
        stw     r11,PT_REGS(r12)
 #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
-       lwz     r12,PTRACE-THREAD(r12)
-       andi.   r12,r12,PT_PTRACED
+       /* Check to see if the dbcr0 register is set up to debug.  Use the
+          single-step bit to do this. */
+       lwz     r12,THREAD_DBCR0(r12)
+       andis.  r12,r12,DBCR0_IC@h
        beq+    3f
        /* From user and task is ptraced - load up global dbcr0 */
        li      r12,-1                  /* clear all pending debug events */
@@ -242,9 +244,10 @@ ret_from_syscall:
        bne-    syscall_exit_work
 syscall_exit_cont:
 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
-       /* If the process has its own DBCR0 value, load it up */
-       lwz     r0,PTRACE(r2)
-       andi.   r0,r0,PT_PTRACED
+       /* If the process has its own DBCR0 value, load it up.  The single
+          step bit tells us that dbcr0 should be loaded. */
+       lwz     r0,THREAD+THREAD_DBCR0(r2)
+       andis.  r10,r0,DBCR0_IC@h
        bnel-   load_dbcr0
 #endif
        stwcx.  r0,0,r1                 /* to clear the reservation */
@@ -599,9 +602,10 @@ user_exc_return:           /* r10 contains MSR_KERNEL here */
 
 restore_user:
 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
-       /* Check whether this process has its own DBCR0 value */
-       lwz     r0,PTRACE(r2)
-       andi.   r0,r0,PT_PTRACED
+       /* Check whether this process has its own DBCR0 value.  The single
+          step bit tells us that dbcr0 should be loaded. */
+       lwz     r0,THREAD+THREAD_DBCR0(r2)
+       andis.  r10,r0,DBCR0_IC@h
        bnel-   load_dbcr0
 #endif
 
@@ -620,18 +624,8 @@ resume_kernel:
        beq+    restore
        andi.   r0,r3,MSR_EE    /* interrupts off? */
        beq     restore         /* don't schedule if so */
-1:     lis     r0,PREEMPT_ACTIVE@h
-       stw     r0,TI_PREEMPT(r9)
-       ori     r10,r10,MSR_EE
-       SYNC
-       MTMSRD(r10)             /* hard-enable interrupts */
-       bl      schedule
-       LOAD_MSR_KERNEL(r10,MSR_KERNEL)
-       SYNC
-       MTMSRD(r10)             /* disable interrupts */
+1:     bl      preempt_schedule_irq
        rlwinm  r9,r1,0,0,18
-       li      r0,0
-       stw     r0,TI_PREEMPT(r9)
        lwz     r3,TI_FLAGS(r9)
        andi.   r0,r3,_TIF_NEED_RESCHED
        bne-    1b
@@ -876,17 +870,17 @@ ret_from_mcheck_exc:
 
 /*
  * Load the DBCR0 value for a task that is being ptraced,
- * having first saved away the global DBCR0.
+ * having first saved away the global DBCR0.  Note that r0
+ * has the dbcr0 value to set upon entry to this.
  */
 load_dbcr0:
-       mfmsr   r0              /* first disable debug exceptions */
-       rlwinm  r0,r0,0,~MSR_DE
-       mtmsr   r0
+       mfmsr   r10             /* first disable debug exceptions */
+       rlwinm  r10,r10,0,~MSR_DE
+       mtmsr   r10
        isync
        mfspr   r10,SPRN_DBCR0
        lis     r11,global_dbcr0@ha
        addi    r11,r11,global_dbcr0@l
-       lwz     r0,THREAD+THREAD_DBCR0(r2)
        stw     r10,0(r11)
        mtspr   SPRN_DBCR0,r0
        lwz     r10,4(r11)