diff options
Diffstat (limited to 'arch/blackfin')
| -rw-r--r-- | arch/blackfin/Kconfig | 1 | ||||
| -rw-r--r-- | arch/blackfin/include/asm/ftrace.h | 14 | ||||
| -rw-r--r-- | arch/blackfin/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/blackfin/kernel/bfin_ksyms.c | 5 | ||||
| -rw-r--r-- | arch/blackfin/kernel/ftrace-entry.S | 72 |
5 files changed, 92 insertions, 1 deletions
diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig index d03fd638e9a..ea8d92c1d44 100644 --- a/arch/blackfin/Kconfig +++ b/arch/blackfin/Kconfig @@ -19,6 +19,7 @@ config RWSEM_XCHGADD_ALGORITHM config BLACKFIN def_bool y + select HAVE_FUNCTION_TRACER select HAVE_IDE select HAVE_KERNEL_GZIP select HAVE_KERNEL_BZIP2 diff --git a/arch/blackfin/include/asm/ftrace.h b/arch/blackfin/include/asm/ftrace.h index 40a8c178f10..8643680f0f7 100644 --- a/arch/blackfin/include/asm/ftrace.h +++ b/arch/blackfin/include/asm/ftrace.h @@ -1 +1,13 @@ -/* empty */ +/* + * Blackfin ftrace code + * + * Copyright 2009 Analog Devices Inc. + * Licensed under the GPL-2 or later. + */ + +#ifndef __ASM_BFIN_FTRACE_H__ +#define __ASM_BFIN_FTRACE_H__ + +#define MCOUNT_INSN_SIZE 8 /* sizeof mcount call: LINK + CALL */ + +#endif diff --git a/arch/blackfin/kernel/Makefile b/arch/blackfin/kernel/Makefile index a66dda4f4b1..d2ae285e5b6 100644 --- a/arch/blackfin/kernel/Makefile +++ b/arch/blackfin/kernel/Makefile @@ -15,6 +15,7 @@ else obj-y += time.o endif +obj-$(CONFIG_FUNCTION_TRACER) += ftrace-entry.o obj-$(CONFIG_IPIPE) += ipipe.o obj-$(CONFIG_IPIPE_TRACE_MCOUNT) += mcount.o obj-$(CONFIG_BFIN_GPTIMERS) += gptimers.o diff --git a/arch/blackfin/kernel/bfin_ksyms.c b/arch/blackfin/kernel/bfin_ksyms.c index 53e893ff708..aa05e638fb7 100644 --- a/arch/blackfin/kernel/bfin_ksyms.c +++ b/arch/blackfin/kernel/bfin_ksyms.c @@ -103,3 +103,8 @@ EXPORT_SYMBOL(__raw_smp_mark_barrier_asm); EXPORT_SYMBOL(__raw_smp_check_barrier_asm); #endif #endif + +#ifdef CONFIG_FUNCTION_TRACER +extern void _mcount(void); +EXPORT_SYMBOL(_mcount); +#endif diff --git a/arch/blackfin/kernel/ftrace-entry.S b/arch/blackfin/kernel/ftrace-entry.S new file mode 100644 index 00000000000..ce71487b515 --- /dev/null +++ b/arch/blackfin/kernel/ftrace-entry.S @@ -0,0 +1,72 @@ +/* + * mcount and friends -- ftrace stuff + * + * Copyright (C) 2009 Analog Devices Inc. + * Licensed under the GPL-2 or later. + */ + +#include <linux/linkage.h> +#include <asm/ftrace.h> + +.text + +/* GCC will have called us before setting up the function prologue, so we + * can clobber the normal scratch registers, but we need to make sure to + * save/restore the registers used for argument passing (R0-R2) in case + * the profiled function is using them. With data registers, R3 is the + * only one we can blow away. With pointer registers, we have P0-P2. + * + * Upon entry, the RETS will point to the top of the current profiled + * function. And since GCC setup the frame for us, the previous function + * will be waiting there. mmmm pie. + */ +ENTRY(__mcount) + /* save third function arg early so we can do testing below */ + [--sp] = r2; + + /* load the function pointer to the tracer */ + p0.l = _ftrace_trace_function; + p0.h = _ftrace_trace_function; + r3 = [p0]; + + /* optional micro optimization: don't call the stub tracer */ + r2.l = _ftrace_stub; + r2.h = _ftrace_stub; + cc = r2 == r3; + if ! cc jump .Ldo_trace; + + r2 = [sp++]; + rts; + +.Ldo_trace: + + /* save first/second function arg and the return register */ + [--sp] = r0; + [--sp] = r1; + [--sp] = rets; + + /* setup the tracer function */ + p0 = r3; + + /* tracer(ulong frompc, ulong selfpc): + * frompc: the pc that did the call to ... + * selfpc: ... this location + * the selfpc itself will need adjusting for the mcount call + */ + r1 = rets; + r0 = [fp + 4]; + r1 += -MCOUNT_INSN_SIZE; + + /* call the tracer */ + call (p0); + + /* restore state and get out of dodge */ + rets = [sp++]; + r1 = [sp++]; + r0 = [sp++]; + r2 = [sp++]; + +.globl _ftrace_stub +_ftrace_stub: + rts; +ENDPROC(__mcount) |