powerpc: tracing: Give hypervisor call tracepoints access to arguments
While most users of the hcall tracepoints will only want the opcode
and return code, some will want all the arguments. To avoid the
complexity of using varargs we pass a pointer to the register save
area, which contains all the arguments.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 01e95ab..383a5d0 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -30,7 +30,7 @@
* in early init (eg when populating the MMU hashtable) by using an
* unconditional cpu feature.
*/
-#define HCALL_INST_PRECALL \
+#define HCALL_INST_PRECALL(FIRST_REG) \
BEGIN_FTR_SECTION; \
b 1f; \
END_FTR_SECTION(0, 1); \
@@ -47,6 +47,7 @@
std r9,STK_PARM(r9)(r1); \
std r10,STK_PARM(r10)(r1); \
std r0,16(r1); \
+ addi r4,r1,STK_PARM(FIRST_REG); \
stdu r1,-STACK_FRAME_OVERHEAD(r1); \
bl .__trace_hcall_entry; \
addi r1,r1,STACK_FRAME_OVERHEAD; \
@@ -68,7 +69,7 @@
* in early init (eg when populating the MMU hashtable) by using an
* unconditional cpu feature.
*/
-#define HCALL_INST_POSTCALL \
+#define __HCALL_INST_POSTCALL \
BEGIN_FTR_SECTION; \
b 1f; \
END_FTR_SECTION(0, 1); \
@@ -88,9 +89,19 @@
ld r3,STK_PARM(r3)(r1); \
mtlr r0; \
1:
+
+#define HCALL_INST_POSTCALL_NORETS \
+ li r5,0; \
+ __HCALL_INST_POSTCALL
+
+#define HCALL_INST_POSTCALL(BUFREG) \
+ mr r5,BUFREG; \
+ __HCALL_INST_POSTCALL
+
#else
-#define HCALL_INST_PRECALL
-#define HCALL_INST_POSTCALL
+#define HCALL_INST_PRECALL(FIRST_ARG)
+#define HCALL_INST_POSTCALL_NORETS
+#define HCALL_INST_POSTCALL(BUFREG)
#endif
.text
@@ -101,11 +112,11 @@
mfcr r0
stw r0,8(r1)
- HCALL_INST_PRECALL
+ HCALL_INST_PRECALL(r4)
HVSC /* invoke the hypervisor */
- HCALL_INST_POSTCALL
+ HCALL_INST_POSTCALL_NORETS
lwz r0,8(r1)
mtcrf 0xff,r0
@@ -117,7 +128,7 @@
mfcr r0
stw r0,8(r1)
- HCALL_INST_PRECALL
+ HCALL_INST_PRECALL(r5)
std r4,STK_PARM(r4)(r1) /* Save ret buffer */
@@ -136,7 +147,7 @@
std r6, 16(r12)
std r7, 24(r12)
- HCALL_INST_POSTCALL
+ HCALL_INST_POSTCALL(r12)
lwz r0,8(r1)
mtcrf 0xff,r0
@@ -183,7 +194,7 @@
mfcr r0
stw r0,8(r1)
- HCALL_INST_PRECALL
+ HCALL_INST_PRECALL(r5)
std r4,STK_PARM(r4)(r1) /* Save ret buffer */
@@ -211,7 +222,7 @@
std r11,56(r12)
std r0, 64(r12)
- HCALL_INST_POSTCALL
+ HCALL_INST_POSTCALL(r12)
lwz r0,8(r1)
mtcrf 0xff,r0