[PATCH 6/7][RFC] powerpc32, ftrace: port function graph tracer to ppc32, static only
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2009-02-12 01:14:37
Also in:
lkml
Subsystem:
function hooks (ftrace), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Steven Rostedt, Masami Hiramatsu, Madhavan Srinivasan, Linus Torvalds
From: Steven Rostedt <rostedt@goodmis.org> This patch ports the function graph tracer for PowerPC, but only for static function tracing. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> --- arch/powerpc/Kconfig | 2 +- arch/powerpc/kernel/entry_32.S | 43 +++++++++++++++++++++++++++++++++++++++- arch/powerpc/kernel/ftrace.c | 2 +- 3 files changed, 44 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 6e1ee1b..9e4bd20 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig@@ -111,7 +111,7 @@ config PPC select HAVE_FTRACE_MCOUNT_RECORD select HAVE_DYNAMIC_FTRACE select HAVE_FUNCTION_TRACER - select HAVE_FUNCTION_GRAPH_TRACER if PPC64 + select HAVE_FUNCTION_GRAPH_TRACER if PPC64 || !DYNAMIC_FTRACE select ARCH_WANT_OPTIONAL_GPIOLIB select HAVE_IDE select HAVE_IOREMAP_PROT
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index eb0c13e..9cf7083 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S@@ -1199,9 +1199,11 @@ _GLOBAL(_mcount) mtctr r5 bctrl - nop +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + b ftrace_graph_caller +#endif MCOUNT_RESTORE_FRAME bctr
@@ -1210,4 +1212,43 @@ _GLOBAL(_mcount) _GLOBAL(ftrace_stub) blr +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +_GLOBAL(ftrace_graph_caller) + /* load r4 with local address */ + lwz r4, 44(r1) + subi r4, r4, MCOUNT_INSN_SIZE + + /* get the parent address */ + addi r3, r1, 52 + + bl prepare_ftrace_return + nop + + MCOUNT_RESTORE_FRAME + /* old link register ends up in ctr reg */ + bctr + +_GLOBAL(return_to_handler) + /* need to save return values */ + stwu r1, -32(r1) + stw r3, 20(r1) + stw r4, 16(r1) + stw r31, 12(r1) + mr r31, r1 + + bl ftrace_return_to_handler + nop + + /* return value has real return address */ + mtlr r3 + + lwz r3, 20(r1) + lwz r4, 16(r1) + lwz r31,12(r1) + lwz r1, 0(r1) + + /* Jump back to real return address */ + blr +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ + #endif /* CONFIG_MCOUNT */
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 5c6dfa9..dddd99b 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c@@ -603,7 +603,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) "1: " PPC_LL "%[old], 0(%[parent])\n" "2: " PPC_STL "%[return_hooker], 0(%[parent])\n" " li %[faulted], 0\n" - "3:" + "3:\n" ".section .fixup, \"ax\"\n" "4: li %[faulted], 1\n"
--
1.5.6.5
--