From: Mahesh Salgaonkar <mah...@linux.vnet.ibm.com>
This patch splits the common exception prolog logic into three parts to
facilitate reuse of existing code in the next patch. This patch also
re-arranges few instructions in such a way that the second part now deals
with saving register values from paca save area to stack frame, and
the third part deals with saving current register values to stack frame.
The second and third part will be reused in the machine check exception
routine in the subsequent patch.
Please note that this patch does not introduce or change existing code
logic. Instead it is just a code movement and instruction re-ordering.
Patch Acked-by Paul. But made some minor modification (explained above) to
address Paul's comment in the later patch(3).
Signed-off-by: Mahesh Salgaonkar <mah...@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <pau...@samba.org>
---
arch/powerpc/include/asm/exception-64s.h | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/exception-64s.h
b/arch/powerpc/include/asm/exception-64s.h
index 07ca627..94ab2d2 100644
--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -281,9 +281,12 @@ do_kvm_##n:
\
beq 4f; /* if from kernel mode */ \
ACCOUNT_CPU_USER_ENTRY(r9, r10); \
SAVE_PPR(area, r9, r10); \
-4: std r2,GPR2(r1); /* save r2 in stackframe */ \
- SAVE_4GPRS(3, r1); /* save r3 - r6 in stackframe */ \
- SAVE_2GPRS(7, r1); /* save r7, r8 in stackframe */ \
+4: EXCEPTION_PROLOG_COMMON_2(area) \
+ EXCEPTION_PROLOG_COMMON_3(n) \
+ ACCOUNT_STOLEN_TIME
+
+/* Save original regs values from save area to stack frame. */
+#define EXCEPTION_PROLOG_COMMON_2(area)
\
ld r9,area+EX_R9(r13); /* move r9, r10 to stackframe */ \
ld r10,area+EX_R10(r13); \
std r9,GPR9(r1); \
@@ -298,9 +301,14 @@ do_kvm_##n:
\
ld r10,area+EX_CFAR(r13); \
std r10,ORIG_GPR3(r1); \
END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66); \
- GET_LR(r9,area); /* Get LR, later save to stack */ \
+ GET_LR(r9,area); /* Save LR to stack */ \
+ std r9,_LINK(r1);
+
+#define EXCEPTION_PROLOG_COMMON_3(n) \
+ std r2,GPR2(r1); /* save r2 in stackframe */ \
+ SAVE_4GPRS(3, r1); /* save r3 - r6 in stackframe */ \
+ SAVE_2GPRS(7, r1); /* save r7, r8 in stackframe */ \
ld r2,PACATOC(r13); /* get kernel TOC into r2 */ \
- std r9,_LINK(r1); \
mfctr r10; /* save CTR in stackframe */ \
std r10,_CTR(r1); \
lbz r10,PACASOFTIRQEN(r13); \
@@ -312,8 +320,7 @@ do_kvm_##n:
\
li r10,0; \
ld r11,exception_marker@toc(r2); \
std r10,RESULT(r1); /* clear regs->result */ \
- std r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame */ \
- ACCOUNT_STOLEN_TIME
+ std r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame */
/*
* Exception vectors.
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