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>

2 files changed, 7 insertions, 5 deletions

diff --git a/arch/sparc64/kernel/ftrace.c b/arch/sparc64/kernel/ftrace.c
index c17373195b1e..4298d0aee713 100644
--- a/arch/sparc64/kernel/ftrace.c
+++ b/arch/sparc64/kernel/ftrace.c
@@ -5,6 +5,8 @@
 #include <linux/init.h>
 #include <linux/list.h>
 
+#include <asm/ftrace.h>
+
 static const u32 ftrace_nop = 0x01000000;
 
 notrace unsigned char *ftrace_nop_replace(void)
@@ -60,9 +62,9 @@ ftrace_modify_code(unsigned long ip, unsigned char *old_code,
 notrace int ftrace_update_ftrace_func(ftrace_func_t func)
 {
         unsigned long ip = (unsigned long)(&ftrace_call);
-        unsigned char old[4], *new;
+        unsigned char old[MCOUNT_INSN_SIZE], *new;
 
-        memcpy(old, &ftrace_call, 4);
+        memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE);
         new = ftrace_call_replace(ip, (unsigned long)func);
         return ftrace_modify_code(ip, old, new);
 }
@@ -71,13 +73,13 @@ notrace int ftrace_mcount_set(unsigned long *data)
 {
         unsigned long ip = (long)(&mcount_call);
         unsigned long *addr = data;
-        unsigned char old[4], *new;
+        unsigned char old[MCOUNT_INSN_SIZE], *new;
 
         /*
          * Replace the mcount stub with a pointer to the
          * ip recorder function.
          */
-        memcpy(old, &mcount_call, 4);
+        memcpy(old, &mcount_call, MCOUNT_INSN_SIZE);
         new = ftrace_call_replace(ip, *addr);
         *addr = ftrace_modify_code(ip, old, new);
 
diff --git a/arch/sparc64/kernel/sparc64_ksyms.c b/arch/sparc64/kernel/sparc64_ksyms.c
index 8ac0b99f2c55..b80d982a29c6 100644
--- a/arch/sparc64/kernel/sparc64_ksyms.c
+++ b/arch/sparc64/kernel/sparc64_ksyms.c
@@ -53,6 +53,7 @@
 #include <asm/ns87303.h>
 #include <asm/timer.h>
 #include <asm/cpudata.h>
+#include <asm/ftrace.h>
 
 struct poll {
         int fd;
@@ -112,7 +113,6 @@ EXPORT_SYMBOL(smp_call_function);
 #endif /* CONFIG_SMP */
 
 #if defined(CONFIG_MCOUNT)
-extern void _mcount(void);
 EXPORT_SYMBOL(_mcount);
 #endif