[PATCH 6/8] powerpc/ftrace: Add support for HAVE_FUNCTION_GRAPH_FP_TEST for -mprofile-kernel
Naveen N. Rao
naveen.n.rao at linux.vnet.ibm.com
Thu May 4 14:36:19 AEST 2017
This is very handy to catch potential crashes due to unexpected
interactions of function_graph tracer with weird things like
jprobes.
Signed-off-by: Naveen N. Rao <naveen.n.rao at linux.vnet.ibm.com>
---
arch/powerpc/include/asm/asm-prototypes.h | 3 ++-
arch/powerpc/include/asm/ftrace.h | 3 +++
arch/powerpc/kernel/trace/ftrace.c | 4 ++--
arch/powerpc/kernel/trace/ftrace_64.S | 1 +
arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 1 +
5 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 7330150bfe34..14964ab80a53 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -124,6 +124,7 @@ extern int __ucmpdi2(u64, u64);
/* tracing */
void _mcount(void);
-unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip);
+unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,
+ unsigned long fp);
#endif /* _ASM_POWERPC_ASM_PROTOTYPES_H */
diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h
index 686c5f70eb84..2b89043b0c61 100644
--- a/arch/powerpc/include/asm/ftrace.h
+++ b/arch/powerpc/include/asm/ftrace.h
@@ -6,6 +6,9 @@
#ifdef CONFIG_FUNCTION_TRACER
#define MCOUNT_ADDR ((unsigned long)(_mcount))
#define MCOUNT_INSN_SIZE 4 /* sizeof mcount call */
+#ifdef CONFIG_MPROFILE_KERNEL
+#define HAVE_FUNCTION_GRAPH_FP_TEST
+#endif
#ifdef __ASSEMBLY__
diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index 32509de6ce4c..7e3e099cdfe4 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -572,7 +572,7 @@ int ftrace_disable_ftrace_graph_caller(void)
* Hook the return address and push it in the stack of return addrs
* in current thread info. Return the address we want to divert to.
*/
-unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip)
+unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long fp)
{
struct ftrace_graph_ent trace;
unsigned long return_hooker;
@@ -592,7 +592,7 @@ unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip)
if (!ftrace_graph_entry(&trace))
goto out;
- if (ftrace_push_return_trace(parent, ip, &trace.depth, 0,
+ if (ftrace_push_return_trace(parent, ip, &trace.depth, fp,
NULL) == -EBUSY)
goto out;
diff --git a/arch/powerpc/kernel/trace/ftrace_64.S b/arch/powerpc/kernel/trace/ftrace_64.S
index e5ccea19821e..57ab4f73a5c4 100644
--- a/arch/powerpc/kernel/trace/ftrace_64.S
+++ b/arch/powerpc/kernel/trace/ftrace_64.S
@@ -68,6 +68,7 @@ _GLOBAL(return_to_handler)
*/
ld r2, PACATOC(r13)
+ addi r3, r1, 112
bl ftrace_return_to_handler
nop
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index 981b99dc3029..fb6910e48f22 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -241,6 +241,7 @@ _GLOBAL(ftrace_graph_caller)
ld r3, _LINK(r1)
subi r4, r14, MCOUNT_INSN_SIZE /* load saved original NIP */
+ addi r5, r1, SWITCH_FRAME_SIZE
bl prepare_ftrace_return
nop
--
2.12.2
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