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Diffstat (limited to 'arch/powerpc/kernel/entry_64.S')
-rw-r--r--arch/powerpc/kernel/entry_64.S134
1 files changed, 59 insertions, 75 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index ed1718feb9d..4b01a25e29e 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -146,7 +146,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
REST_2GPRS(7,r1)
addi r9,r1,STACK_FRAME_OVERHEAD
#endif
- clrrdi r11,r1,THREAD_SHIFT
+ CURRENT_THREAD_INFO(r11, r1)
ld r10,TI_FLAGS(r11)
andi. r11,r10,_TIF_SYSCALL_T_OR_A
bne- syscall_dotrace
@@ -181,7 +181,7 @@ syscall_exit:
bl .do_show_syscall_exit
ld r3,RESULT(r1)
#endif
- clrrdi r12,r1,THREAD_SHIFT
+ CURRENT_THREAD_INFO(r12, r1)
ld r8,_MSR(r1)
#ifdef CONFIG_PPC_BOOK3S
@@ -197,7 +197,16 @@ syscall_exit:
wrteei 0
#else
ld r10,PACAKMSR(r13)
- mtmsrd r10,1
+ /*
+ * For performance reasons we clear RI the same time that we
+ * clear EE. We only need to clear RI just before we restore r13
+ * below, but batching it with EE saves us one expensive mtmsrd call.
+ * We have to be careful to restore RI if we branch anywhere from
+ * here (eg syscall_exit_work).
+ */
+ li r9,MSR_RI
+ andc r11,r10,r9
+ mtmsrd r11,1
#endif /* CONFIG_PPC_BOOK3E */
ld r9,TI_FLAGS(r12)
@@ -214,17 +223,6 @@ BEGIN_FTR_SECTION
END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
andi. r6,r8,MSR_PR
ld r4,_LINK(r1)
- /*
- * Clear RI before restoring r13. If we are returning to
- * userspace and we take an exception after restoring r13,
- * we end up corrupting the userspace r13 value.
- */
-#ifdef CONFIG_PPC_BOOK3S
- /* No MSR:RI on BookE */
- li r12,MSR_RI
- andc r11,r10,r12
- mtmsrd r11,1 /* clear MSR.RI */
-#endif /* CONFIG_PPC_BOOK3S */
beq- 1f
ACCOUNT_CPU_USER_EXIT(r11, r12)
@@ -262,7 +260,7 @@ syscall_dotrace:
ld r7,GPR7(r1)
ld r8,GPR8(r1)
addi r9,r1,STACK_FRAME_OVERHEAD
- clrrdi r10,r1,THREAD_SHIFT
+ CURRENT_THREAD_INFO(r10, r1)
ld r10,TI_FLAGS(r10)
b .Lsyscall_dotrace_cont
@@ -271,6 +269,9 @@ syscall_enosys:
b syscall_exit
syscall_exit_work:
+#ifdef CONFIG_PPC_BOOK3S
+ mtmsrd r10,1 /* Restore RI */
+#endif
/* If TIF_RESTOREALL is set, don't scribble on either r3 or ccr.
If TIF_NOERROR is set, just save r3 as it is. */
@@ -499,7 +500,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
2:
#endif /* !CONFIG_PPC_BOOK3S */
- clrrdi r7,r8,THREAD_SHIFT /* base of new stack */
+ CURRENT_THREAD_INFO(r7, r8) /* base of new stack */
/* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE
because we don't need to leave the 288-byte ABI gap at the
top of the kernel stack. */
@@ -558,27 +559,54 @@ _GLOBAL(ret_from_except_lite)
mtmsrd r10,1 /* Update machine state */
#endif /* CONFIG_PPC_BOOK3E */
-#ifdef CONFIG_PREEMPT
- clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */
- li r0,_TIF_NEED_RESCHED /* bits to check */
+ CURRENT_THREAD_INFO(r9, r1)
ld r3,_MSR(r1)
ld r4,TI_FLAGS(r9)
- /* Move MSR_PR bit in r3 to _TIF_SIGPENDING position in r0 */
- rlwimi r0,r3,32+TIF_SIGPENDING-MSR_PR_LG,_TIF_SIGPENDING
- and. r0,r4,r0 /* check NEED_RESCHED and maybe SIGPENDING */
- bne do_work
-
-#else /* !CONFIG_PREEMPT */
- ld r3,_MSR(r1) /* Returning to user mode? */
andi. r3,r3,MSR_PR
- beq restore /* if not, just restore regs and return */
+ beq resume_kernel
/* Check current_thread_info()->flags */
- clrrdi r9,r1,THREAD_SHIFT
- ld r4,TI_FLAGS(r9)
andi. r0,r4,_TIF_USER_WORK_MASK
- bne do_work
-#endif /* !CONFIG_PREEMPT */
+ beq restore
+
+ andi. r0,r4,_TIF_NEED_RESCHED
+ beq 1f
+ bl .restore_interrupts
+ bl .schedule
+ b .ret_from_except_lite
+
+1: bl .save_nvgprs
+ bl .restore_interrupts
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .do_notify_resume
+ b .ret_from_except
+
+resume_kernel:
+#ifdef CONFIG_PREEMPT
+ /* Check if we need to preempt */
+ andi. r0,r4,_TIF_NEED_RESCHED
+ beq+ restore
+ /* Check that preempt_count() == 0 and interrupts are enabled */
+ lwz r8,TI_PREEMPT(r9)
+ cmpwi cr1,r8,0
+ ld r0,SOFTE(r1)
+ cmpdi r0,0
+ crandc eq,cr1*4+eq,eq
+ bne restore
+
+ /*
+ * Here we are preempting the current task. We want to make
+ * sure we are soft-disabled first
+ */
+ SOFT_DISABLE_INTS(r3,r4)
+1: bl .preempt_schedule_irq
+
+ /* Re-test flags and eventually loop */
+ CURRENT_THREAD_INFO(r9, r1)
+ ld r4,TI_FLAGS(r9)
+ andi. r0,r4,_TIF_NEED_RESCHED
+ bne 1b
+#endif /* CONFIG_PREEMPT */
.globl fast_exc_return_irq
fast_exc_return_irq:
@@ -759,50 +787,6 @@ restore_check_irq_replay:
#endif /* CONFIG_PPC_BOOK3E */
1: b .ret_from_except /* What else to do here ? */
-
-
-3:
-do_work:
-#ifdef CONFIG_PREEMPT
- andi. r0,r3,MSR_PR /* Returning to user mode? */
- bne user_work
- /* Check that preempt_count() == 0 and interrupts are enabled */
- lwz r8,TI_PREEMPT(r9)
- cmpwi cr1,r8,0
- ld r0,SOFTE(r1)
- cmpdi r0,0
- crandc eq,cr1*4+eq,eq
- bne restore
-
- /*
- * Here we are preempting the current task. We want to make
- * sure we are soft-disabled first
- */
- SOFT_DISABLE_INTS(r3,r4)
-1: bl .preempt_schedule_irq
-
- /* Re-test flags and eventually loop */
- clrrdi r9,r1,THREAD_SHIFT
- ld r4,TI_FLAGS(r9)
- andi. r0,r4,_TIF_NEED_RESCHED
- bne 1b
- b restore
-
-user_work:
-#endif /* CONFIG_PREEMPT */
-
- andi. r0,r4,_TIF_NEED_RESCHED
- beq 1f
- bl .restore_interrupts
- bl .schedule
- b .ret_from_except_lite
-
-1: bl .save_nvgprs
- bl .restore_interrupts
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl .do_notify_resume
- b .ret_from_except
-
unrecov_restore:
addi r3,r1,STACK_FRAME_OVERHEAD
bl .unrecoverable_exception