diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index ccdd8de3c558..e122d241f17d 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -111,6 +111,7 @@ config PPC select HAVE_FTRACE_MCOUNT_RECORD select HAVE_DYNAMIC_FTRACE select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_GRAPH_TRACER if !DYNAMIC_FTRACE && PPC64 select ARCH_WANT_OPTIONAL_GPIOLIB select HAVE_IDE select HAVE_IOREMAP_PROT diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index d15992119085..583ba6493a62 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -18,12 +18,10 @@ CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog CFLAGS_REMOVE_btext.o = -pg -mno-sched-epilog CFLAGS_REMOVE_prom.o = -pg -mno-sched-epilog - -ifdef CONFIG_DYNAMIC_FTRACE -# dynamic ftrace setup. +# do not trace tracer code CFLAGS_REMOVE_ftrace.o = -pg -mno-sched-epilog -endif - +# timers used by tracing +CFLAGS_REMOVE_time.o = -pg -mno-sched-epilog endif obj-y := cputable.o ptrace.o syscalls.o \ @@ -95,6 +93,7 @@ obj-$(CONFIG_AUDIT) += audit.o obj64-$(CONFIG_AUDIT) += compat_audit.o obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o +obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_8XX_MINIMAL_FPEMU) += softemu8xx.o diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 383ed6eb0085..a32699e74c3c 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -931,13 +931,65 @@ _GLOBAL(_mcount) 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 -#endif +#endif /* CONFIG_DYNAMIC_FTRACE */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +ftrace_graph_caller: + /* load r4 with local address */ + ld r4, 128(r1) + subi r4, r4, MCOUNT_INSN_SIZE + + /* get the parent address */ + ld r11, 112(r1) + addi r3, r11, 16 + + bl .prepare_ftrace_return + nop + + ld r0, 128(r1) + mtlr r0 + addi r1, r1, 112 + blr + +_GLOBAL(return_to_handler) + /* need to save return values */ + std r4, -32(r1) + std r3, -24(r1) + /* save TOC */ + std r2, -16(r1) + std r31, -8(r1) + mr r31, r1 + stdu r1, -112(r1) + + /* update the TOC */ + LOAD_REG_IMMEDIATE(r4,ftrace_return_to_handler) + ld r2, 8(r4) + + bl .ftrace_return_to_handler + nop + + /* return value has real return address */ + mtlr r3 + + ld r1, 0(r1) + ld r4, -32(r1) + ld r3, -24(r1) + ld r2, -16(r1) + ld r31, -8(r1) + + /* Jump back to real return address */ + blr +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +#endif /* CONFIG_FUNCTION_TRACER */ diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c index 4112175183d3..c9b1547f65a5 100644 --- a/arch/powerpc/kernel/ftrace.c +++ b/arch/powerpc/kernel/ftrace.c @@ -5,6 +5,9 @@ * * Thanks goes out to P.A. Semi, Inc for supplying me with a PPC64 box. * + * Added function graph tracer code, taken from x86 that was written + * by Frederic Weisbecker, and ported to PPC by Steven Rostedt. + * */ #include @@ -20,8 +23,6 @@ #include #include -static unsigned int ftrace_nop = PPC_NOP_INSTR; - #ifdef CONFIG_PPC32 # define GET_ADDR(addr) addr #else @@ -29,6 +30,8 @@ static unsigned int ftrace_nop = PPC_NOP_INSTR; # define GET_ADDR(addr) (*(unsigned long *)addr) #endif +#ifdef CONFIG_DYNAMIC_FTRACE +static unsigned int ftrace_nop = PPC_NOP_INSTR; static unsigned int ftrace_calc_offset(long ip, long addr) { @@ -525,3 +528,75 @@ int __init ftrace_dyn_arch_init(void *data) return 0; } +#endif /* CONFIG_DYNAMIC_FTRACE */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + +/* + * Hook the return address and push it in the stack of return addrs + * in current thread info. + */ +void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) +{ + unsigned long old; + unsigned long long calltime; + int faulted; + struct ftrace_graph_ent trace; + unsigned long return_hooker = (unsigned long) + &return_to_handler; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + + return_hooker = GET_ADDR(return_hooker); + + /* + * Protect against fault, even if it shouldn't + * happen. This tool is too much intrusive to + * ignore such a protection. + */ + asm volatile( + "1: " PPC_LL "%[old], 0(%[parent])\n" + "2: " PPC_STL "%[return_hooker], 0(%[parent])\n" + " li %[faulted], 0\n" + "3:" + + ".section .fixup, \"ax\"\n" + "4: li %[faulted], 1\n" + " b 3b\n" + ".previous\n" + + ".section __ex_table,\"a\"\n" + PPC_LONG_ALIGN "\n" + PPC_LONG "1b,4b\n" + PPC_LONG "2b,4b\n" + ".previous" + + : [old] "=r" (old), [faulted] "=r" (faulted) + : [parent] "r" (parent), [return_hooker] "r" (return_hooker) + : "memory" + ); + + if (unlikely(faulted)) { + ftrace_graph_stop(); + WARN_ON(1); + return; + } + + calltime = cpu_clock(raw_smp_processor_id()); + + if (ftrace_push_return_trace(old, calltime, + self_addr, &trace.depth) == -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 */ diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index fb7049c054c0..8ede428e76c0 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -1008,6 +1009,14 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) unsigned long sp, ip, lr, newsp; int count = 0; int firstframe = 1; +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + int curr_frame = current->curr_ret_stack; + extern void return_to_handler(void); + unsigned long addr = (unsigned long)return_to_handler; +#ifdef CONFIG_PPC64 + addr = *(unsigned long*)addr; +#endif +#endif sp = (unsigned long) stack; if (tsk == NULL) @@ -1030,6 +1039,13 @@ void show_stack(struct task_struct *tsk, unsigned long *stack) ip = stack[STACK_FRAME_LR_SAVE]; if (!firstframe || ip != lr) { printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + if (ip == addr && curr_frame >= 0) { + printk(" (%pS)", + (void *)current->ret_stack[curr_frame].ret); + curr_frame--; + } +#endif if (firstframe) printk(" (unreliable)"); printk("\n"); diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 161b9b9691f0..895af44bf1f4 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -58,6 +58,7 @@ SECTIONS SCHED_TEXT LOCK_TEXT KPROBES_TEXT + IRQENTRY_TEXT #ifdef CONFIG_PPC32 *(.got1)