diff options
| -rw-r--r-- | arch/arm/kernel/Makefile | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/entry-common.S | 46 | ||||
| -rw-r--r-- | arch/arm/kernel/ftrace.c | 34 |
3 files changed, 82 insertions, 1 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 5b9b268f4fb..679851a9f58 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -5,7 +5,7 @@ CPPFLAGS_vmlinux.lds := -DTEXT_OFFSET=$(TEXT_OFFSET) AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) -ifdef CONFIG_DYNAMIC_FTRACE +ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_ftrace.o = -pg endif @@ -33,6 +33,7 @@ obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_HAVE_ARM_SCU) += smp_scu.o obj-$(CONFIG_HAVE_ARM_TWD) += smp_twd.o obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o +obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o obj-$(CONFIG_KPROBES) += kprobes.o kprobes-decode.o obj-$(CONFIG_ATAGS_PROC) += atags.o diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index fe1d5862b19..9f176621166 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -148,6 +148,20 @@ ENDPROC(ret_from_fork) adr r0, .Lftrace_stub cmp r0, r2 bne 1f + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + ldr r1, =ftrace_graph_return + ldr r2, [r1] + cmp r0, r2 + bne ftrace_graph_caller\suffix + + ldr r1, =ftrace_graph_entry + ldr r2, [r1] + ldr r0, =ftrace_graph_entry_stub + cmp r0, r2 + bne ftrace_graph_caller\suffix +#endif + mcount_exit 1: mcount_get_lr r1 @ lr of instrumented func @@ -172,6 +186,15 @@ ftrace_call\suffix: mcount_exit .endm +.macro __ftrace_graph_caller + sub r0, fp, #4 @ &lr of instrumented routine (&parent) + mov r1, lr @ instrumented routine (func) + sub r1, r1, #MCOUNT_INSN_SIZE + mov r2, fp @ frame pointer + bl prepare_ftrace_return + mcount_exit +.endm + #ifdef CONFIG_OLD_MCOUNT /* * mcount @@ -206,6 +229,12 @@ ENTRY(ftrace_caller_old) ENDPROC(ftrace_caller_old) #endif +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +ENTRY(ftrace_graph_caller_old) + __ftrace_graph_caller +ENDPROC(ftrace_graph_caller_old) +#endif + .purgem mcount_enter .purgem mcount_get_lr .purgem mcount_exit @@ -244,10 +273,27 @@ ENTRY(ftrace_caller) ENDPROC(ftrace_caller) #endif +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +ENTRY(ftrace_graph_caller) + __ftrace_graph_caller +ENDPROC(ftrace_graph_caller) +#endif + .purgem mcount_enter .purgem mcount_get_lr .purgem mcount_exit +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + .globl return_to_handler +return_to_handler: + stmdb sp!, {r0-r3} + mov r0, fp @ frame pointer + bl ftrace_return_to_handler + mov lr, r0 @ r0 has real ret addr + ldmia sp!, {r0-r3} + mov pc, lr +#endif + ENTRY(ftrace_stub) .Lftrace_stub: mov pc, lr diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index 971ac8c36ea..7a702a50287 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -24,6 +24,7 @@ #define NOP 0xe8bd4000 /* pop {lr} */ #endif +#ifdef CONFIG_DYNAMIC_FTRACE #ifdef CONFIG_OLD_MCOUNT #define OLD_MCOUNT_ADDR ((unsigned long) mcount) #define OLD_FTRACE_ADDR ((unsigned long) ftrace_caller_old) @@ -193,3 +194,36 @@ int __init ftrace_dyn_arch_init(void *data) return 0; } +#endif /* CONFIG_DYNAMIC_FTRACE */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, + unsigned long frame_pointer) +{ + unsigned long return_hooker = (unsigned long) &return_to_handler; + struct ftrace_graph_ent trace; + unsigned long old; + int err; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + old = *parent; + *parent = return_hooker; + + err = ftrace_push_return_trace(old, self_addr, &trace.depth, + frame_pointer); + if (err == -EBUSY) { + *parent = old; + return; + } + + trace.func = self_addr; + + /* Only trace if the calling function expects to */ + if (!ftrace_graph_entry(&trace)) { + current->curr_ret_stack--; + *parent = old; + } +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |