ftrace: store mcount address in rec->ip

Record the address of the mcount call-site. Currently all archs except sparc64
record the address of the instruction following the mcount call-site. Some
general cleanups are entailed. Storing mcount addresses in rec->ip enables
looking them up in the kprobe hash table later on to check if they're kprobe'd.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Cc: davem@davemloft.net
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 2c4d9e056ead..2f511a969d2c 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -31,6 +31,7 @@
 #include <asm/bug.h>
 #include <asm/ptrace.h>
 #include <asm/irqflags.h>
+#include <asm/ftrace.h>
 
 /*
  * System calls.
@@ -879,6 +880,7 @@ _GLOBAL(_mcount)
         mflr    r3
         stdu    r1, -112(r1)
         std     r3, 128(r1)
+        subi    r3, r3, MCOUNT_INSN_SIZE
         .globl mcount_call
 mcount_call:
         bl      ftrace_stub
@@ -895,6 +897,7 @@ _GLOBAL(ftrace_caller)
         stdu    r1, -112(r1)
         std     r3, 128(r1)
         ld      r4, 16(r11)
+        subi    r3, r3, MCOUNT_INSN_SIZE
 .globl ftrace_call
 ftrace_call:
         bl      ftrace_stub
@@ -916,7 +919,7 @@ _GLOBAL(_mcount)
         std     r3, 128(r1)
         ld      r4, 16(r11)
 
-
+        subi    r3, r3, MCOUNT_INSN_SIZE
         LOAD_REG_ADDR(r5,ftrace_trace_function)
         ld      r5,0(r5)
         ld      r5,0(r5)