[RFC PATCH 2/2] powerpc: Only support DYNAMIC_FTRACE not static
From: Michael Ellerman
Date: Fri Mar 16 2018 - 09:46:58 EST
We've had dynamic ftrace support for over 9 years since Steve first
wrote it, all the distros use dynamic, and static is basically
untested these days, so drop support for static ftrace.
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/ftrace.h | 4 +---
arch/powerpc/include/asm/module.h | 5 -----
arch/powerpc/kernel/trace/ftrace.c | 2 --
arch/powerpc/kernel/trace/ftrace_32.S | 20 ------------------
arch/powerpc/kernel/trace/ftrace_64.S | 29 --------------------------
arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 3 ---
arch/powerpc/kernel/trace/ftrace_64_pg.S | 2 --
8 files changed, 2 insertions(+), 64 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 73ce5dd07642..23a325df784a 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -189,6 +189,7 @@ config PPC
select HAVE_DEBUG_STACKOVERFLOW
select HAVE_DMA_API_DEBUG
select HAVE_DYNAMIC_FTRACE
+ select HAVE_DYNAMIC_FTRACE_ONLY
select HAVE_DYNAMIC_FTRACE_WITH_REGS if MPROFILE_KERNEL
select HAVE_EBPF_JIT if PPC64
select HAVE_EFFICIENT_UNALIGNED_ACCESS if !(CPU_LITTLE_ENDIAN && POWER7_CPU)
diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h
index 9abddde372ab..e6c34d740ee9 100644
--- a/arch/powerpc/include/asm/ftrace.h
+++ b/arch/powerpc/include/asm/ftrace.h
@@ -48,7 +48,6 @@
#else /* !__ASSEMBLY__ */
extern void _mcount(void);
-#ifdef CONFIG_DYNAMIC_FTRACE
# define FTRACE_ADDR ((unsigned long)ftrace_caller)
# define FTRACE_REGS_ADDR FTRACE_ADDR
static inline unsigned long ftrace_call_adjust(unsigned long addr)
@@ -60,13 +59,12 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr)
struct dyn_arch_ftrace {
struct module *mod;
};
-#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* __ASSEMBLY__ */
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
#define ARCH_SUPPORTS_FTRACE_OPS 1
#endif
-#endif
+#endif /* CONFIG_FUNCTION_TRACER */
#if defined(CONFIG_FTRACE_SYSCALLS) && !defined(__ASSEMBLY__)
#ifdef PPC64_ELF_ABI_v1
diff --git a/arch/powerpc/include/asm/module.h b/arch/powerpc/include/asm/module.h
index 7e28442827f1..e09c96d0db69 100644
--- a/arch/powerpc/include/asm/module.h
+++ b/arch/powerpc/include/asm/module.h
@@ -90,11 +90,6 @@ int module_trampoline_target(struct module *mod, unsigned long trampoline,
#ifdef CONFIG_DYNAMIC_FTRACE
int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs);
-#else
-static inline int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
-{
- return 0;
-}
#endif
#endif /* __KERNEL__ */
diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index 4741fe112f05..c6d196d85260 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -538,7 +538,6 @@ int __init ftrace_dyn_arch_init(void)
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-#ifdef CONFIG_DYNAMIC_FTRACE
extern void ftrace_graph_call(void);
extern void ftrace_graph_stub(void);
@@ -567,7 +566,6 @@ int ftrace_disable_ftrace_graph_caller(void)
return ftrace_modify_code(ip, old, new);
}
-#endif /* CONFIG_DYNAMIC_FTRACE */
/*
* Hook the return address and push it in the stack of return addrs
diff --git a/arch/powerpc/kernel/trace/ftrace_32.S b/arch/powerpc/kernel/trace/ftrace_32.S
index afef2c076282..2c29098f630f 100644
--- a/arch/powerpc/kernel/trace/ftrace_32.S
+++ b/arch/powerpc/kernel/trace/ftrace_32.S
@@ -14,7 +14,6 @@
#include <asm/ftrace.h>
#include <asm/export.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL(mcount)
_GLOBAL(_mcount)
/*
@@ -47,26 +46,7 @@ _GLOBAL(ftrace_graph_stub)
MCOUNT_RESTORE_FRAME
/* old link register ends up in ctr reg */
bctr
-#else
-_GLOBAL(mcount)
-_GLOBAL(_mcount)
-
- MCOUNT_SAVE_FRAME
- subi r3, r3, MCOUNT_INSN_SIZE
- LOAD_REG_ADDR(r5, ftrace_trace_function)
- lwz r5,0(r5)
-
- mtctr r5
- bctrl
- nop
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- b ftrace_graph_caller
-#endif
- MCOUNT_RESTORE_FRAME
- bctr
-#endif
EXPORT_SYMBOL(_mcount)
_GLOBAL(ftrace_stub)
diff --git a/arch/powerpc/kernel/trace/ftrace_64.S b/arch/powerpc/kernel/trace/ftrace_64.S
index e5ccea19821e..e25f77c10a72 100644
--- a/arch/powerpc/kernel/trace/ftrace_64.S
+++ b/arch/powerpc/kernel/trace/ftrace_64.S
@@ -14,7 +14,6 @@
#include <asm/ppc-opcode.h>
#include <asm/export.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL(mcount)
_GLOBAL(_mcount)
EXPORT_SYMBOL(_mcount)
@@ -23,34 +22,6 @@ EXPORT_SYMBOL(_mcount)
mtlr r0
bctr
-#else /* CONFIG_DYNAMIC_FTRACE */
-_GLOBAL_TOC(_mcount)
-EXPORT_SYMBOL(_mcount)
- /* Taken from output of objdump from lib64/glibc */
- mflr r3
- ld r11, 0(r1)
- stdu r1, -112(r1)
- 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)
- mtctr r5
- bctrl
- nop
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- b ftrace_graph_caller
-#endif
- ld r0, 128(r1)
- mtlr r0
- addi r1, r1, 112
-_GLOBAL(ftrace_stub)
- blr
-#endif /* CONFIG_DYNAMIC_FTRACE */
-
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(return_to_handler)
/* need to save return values */
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index 3f3e81852422..625f9b758da7 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -17,7 +17,6 @@
#include <asm/bug.h>
#include <asm/ptrace.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
/*
*
* ftrace_caller() is the function that replaces _mcount() when ftrace is
@@ -236,8 +235,6 @@ livepatch_handler:
blr
#endif /* CONFIG_LIVEPATCH */
-#endif /* CONFIG_DYNAMIC_FTRACE */
-
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)
stdu r1, -112(r1)
diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.S b/arch/powerpc/kernel/trace/ftrace_64_pg.S
index f095358da96e..f18762827e51 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_pg.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_pg.S
@@ -14,7 +14,6 @@
#include <asm/ppc-opcode.h>
#include <asm/export.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL_TOC(ftrace_caller)
/* Taken from output of objdump from lib64/glibc */
mflr r3
@@ -39,7 +38,6 @@ _GLOBAL(ftrace_graph_stub)
_GLOBAL(ftrace_stub)
blr
-#endif /* CONFIG_DYNAMIC_FTRACE */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)
--
2.14.1