powerpc: Make syscall tracing use tracehook.h helpers
This changes powerpc syscall tracing to use the new tracehook.h entry
points. There is no change, only cleanup.
In addition, the assembly changes allow do_syscall_trace_enter() to
abort the syscall without losing the information about the original
r0 value.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index da52269..e6fca6a 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -343,7 +343,12 @@
stw r0,_TRAP(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_syscall_trace_enter
- lwz r0,GPR0(r1) /* Restore original registers */
+ /*
+ * Restore argument registers possibly just changed.
+ * We use the return value of do_syscall_trace_enter
+ * for call number to look up in the table (r0).
+ */
+ mr r0,r3
lwz r3,GPR3(r1)
lwz r4,GPR4(r1)
lwz r5,GPR5(r1)