Merge branch 'tracing/ftrace' into auto-ftrace-next

89 files changed, 8834 insertions, 115 deletions

diff --git a/Makefile b/Makefile
index 6315424a00b..8e519953d2d 100644
--- a/Makefile
+++ b/Makefile
@@ -528,6 +528,10 @@ KBUILD_CFLAGS	+= -g
 KBUILD_AFLAGS	+= -gdwarf-2
 endif
 
+ifdef CONFIG_FTRACE
+KBUILD_CFLAGS	+= -pg
+endif
+
 # We trigger additional mismatches with less inlining
 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index b786e68914d..3845e5c8a34 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -14,6 +14,8 @@ config ARM
 	select HAVE_OPROFILE
 	select HAVE_KPROBES if (!XIP_KERNEL)
 	select HAVE_KRETPROBES if (HAVE_KPROBES)
+	select HAVE_FTRACE if (!XIP_KERNEL)
+	select HAVE_DYNAMIC_FTRACE if (HAVE_FTRACE)
 	help
 	  The ARM series is a line of low-power-consumption RISC chip designs
 	  licensed by ARM Ltd and targeted at embedded applications and
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index de9d9ee5095..95baac4939e 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -69,6 +69,12 @@ SEDFLAGS	= s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/
 
 targets       := vmlinux vmlinux.lds piggy.gz piggy.o font.o font.c \
 		 head.o misc.o $(OBJS)
+
+ifeq ($(CONFIG_FTRACE),y)
+ORIG_CFLAGS := $(KBUILD_CFLAGS)
+KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
+endif
+
 EXTRA_CFLAGS  := -fpic -fno-builtin
 EXTRA_AFLAGS  :=
 
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index ad455ff5aeb..eb9092ca800 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -4,6 +4,10 @@
 
 AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
 
+ifdef CONFIG_DYNAMIC_FTRACE
+CFLAGS_REMOVE_ftrace.o = -pg
+endif
+
 # Object file lists.
 
 obj-y		:= compat.o entry-armv.o entry-common.o irq.o \
@@ -18,6 +22,7 @@ obj-$(CONFIG_ARTHUR)		+= arthur.o
 obj-$(CONFIG_ISA_DMA)		+= dma-isa.o
 obj-$(CONFIG_PCI)		+= bios32.o isa.o
 obj-$(CONFIG_SMP)		+= smp.o
+obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o
 obj-$(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/armksyms.c b/arch/arm/kernel/armksyms.c
index 688b7b1ee41..cc7b246e965 100644
--- a/arch/arm/kernel/armksyms.c
+++ b/arch/arm/kernel/armksyms.c
@@ -18,6 +18,7 @@
 #include <asm/io.h>
 #include <asm/system.h>
 #include <asm/uaccess.h>
+#include <asm/ftrace.h>
 
 /*
  * libgcc functions - functions that are used internally by the
@@ -181,3 +182,7 @@ EXPORT_SYMBOL(_find_next_bit_be);
 #endif
 
 EXPORT_SYMBOL(copy_page);
+
+#ifdef CONFIG_FTRACE
+EXPORT_SYMBOL(mcount);
+#endif
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 597ed00a08d..84694e88b42 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -9,6 +9,7 @@
  */
 
 #include <asm/unistd.h>
+#include <asm/ftrace.h>
 #include <asm/arch/entry-macro.S>
 
 #include "entry-header.S"
@@ -99,6 +100,56 @@ ENTRY(ret_from_fork)
 #undef CALL
 #define CALL(x) .long x
 
+#ifdef CONFIG_FTRACE
+#ifdef CONFIG_DYNAMIC_FTRACE
+ENTRY(mcount)
+	stmdb sp!, {r0-r3, lr}
+	mov r0, lr
+	sub r0, r0, #MCOUNT_INSN_SIZE
+
+	.globl mcount_call
+mcount_call:
+	bl ftrace_stub
+	ldmia sp!, {r0-r3, pc}
+
+ENTRY(ftrace_caller)
+	stmdb sp!, {r0-r3, lr}
+	ldr r1, [fp, #-4]
+	mov r0, lr
+	sub r0, r0, #MCOUNT_INSN_SIZE
+
+	.globl ftrace_call
+ftrace_call:
+	bl ftrace_stub
+	ldmia sp!, {r0-r3, pc}
+
+#else
+
+ENTRY(mcount)
+	stmdb sp!, {r0-r3, lr}
+	ldr r0, =ftrace_trace_function
+	ldr r2, [r0]
+	adr r0, ftrace_stub
+	cmp r0, r2
+	bne trace
+	ldmia sp!, {r0-r3, pc}
+
+trace:
+	ldr r1, [fp, #-4]
+	mov r0, lr
+	sub r0, r0, #MCOUNT_INSN_SIZE
+	mov lr, pc
+	mov pc, r2
+	ldmia sp!, {r0-r3, pc}
+
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+	.globl ftrace_stub
+ftrace_stub:
+	mov pc, lr
+
+#endif /* CONFIG_FTRACE */
+
 /*=============================================================================
  * SWI handler
  *-----------------------------------------------------------------------------
diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c
new file mode 100644
index 00000000000..76d50e6091b
--- /dev/null
+++ b/arch/arm/kernel/ftrace.c
@@ -0,0 +1,116 @@
+/*
+ * Dynamic function tracing support.
+ *
+ * Copyright (C) 2008 Abhishek Sagar <sagar.abhishek@gmail.com>
+ *
+ * For licencing details, see COPYING.
+ *
+ * Defines low-level handling of mcount calls when the kernel
+ * is compiled with the -pg flag. When using dynamic ftrace, the
+ * mcount call-sites get patched lazily with NOP till they are
+ * enabled. All code mutation routines here take effect atomically.
+ */
+
+#include <linux/ftrace.h>
+
+#include <asm/cacheflush.h>
+#include <asm/ftrace.h>
+
+#define PC_OFFSET      8
+#define BL_OPCODE      0xeb000000
+#define BL_OFFSET_MASK 0x00ffffff
+
+static unsigned long bl_insn;
+static const unsigned long NOP = 0xe1a00000; /* mov r0, r0 */
+
+unsigned char *ftrace_nop_replace(void)
+{
+	return (char *)&NOP;
+}
+
+/* construct a branch (BL) instruction to addr */
+unsigned char *ftrace_call_replace(unsigned long pc, unsigned long addr)
+{
+	long offset;
+
+	offset = (long)addr - (long)(pc + PC_OFFSET);
+	if (unlikely(offset < -33554432 || offset > 33554428)) {
+		/* Can't generate branches that far (from ARM ARM). Ftrace
+		 * doesn't generate branches outside of kernel text.
+		 */
+		WARN_ON_ONCE(1);
+		return NULL;
+	}
+	offset = (offset >> 2) & BL_OFFSET_MASK;
+	bl_insn = BL_OPCODE | offset;
+	return (unsigned char *)&bl_insn;
+}
+
+int ftrace_modify_code(unsigned long pc, unsigned char *old_code,
+		       unsigned char *new_code)
+{
+	unsigned long err = 0, replaced = 0, old, new;
+
+	old = *(unsigned long *)old_code;
+	new = *(unsigned long *)new_code;
+
+	__asm__ __volatile__ (
+		"1:  ldr    %1, [%2]  \n"
+		"    cmp    %1, %4    \n"
+		"2:  streq  %3, [%2]  \n"
+		"    cmpne  %1, %3    \n"
+		"    movne  %0, #2    \n"
+		"3:\n"
+
+		".section .fixup, \"ax\"\n"
+		"4:  mov  %0, #1  \n"
+		"    b    3b      \n"
+		".previous\n"
+
+		".section __ex_table, \"a\"\n"
+		"    .long 1b, 4b \n"
+		"    .long 2b, 4b \n"
+		".previous\n"
+
+		: "=r"(err), "=r"(replaced)
+		: "r"(pc), "r"(new), "r"(old), "0"(err), "1"(replaced)
+		: "memory");
+
+	if (!err && (replaced == old))
+		flush_icache_range(pc, pc + MCOUNT_INSN_SIZE);
+
+	return err;
+}
+
+int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+	int ret;
+	unsigned long pc, old;
+	unsigned char *new;
+
+	pc = (unsigned long)&ftrace_call;
+	memcpy(&old, &ftrace_call, MCOUNT_INSN_SIZE);
+	new = ftrace_call_replace(pc, (unsigned long)func);
+	ret = ftrace_modify_code(pc, (unsigned char *)&old, new);
+	return ret;
+}
+
+int ftrace_mcount_set(unsigned long *data)
+{
+	unsigned long pc, old;
+	unsigned long *addr = data;
+	unsigned char *new;
+
+	pc = (unsigned long)&mcount_call;
+	memcpy(&old, &mcount_call, MCOUNT_INSN_SIZE);
+	new = ftrace_call_replace(pc, *addr);
+	*addr = ftrace_modify_code(pc, (unsigned char *)&old, new);
+	return 0;
+}
+
+/* run from kstop_machine */
+int __init ftrace_dyn_arch_init(void *data)
+{
+	ftrace_mcount_set(data);
+	return 0;
+}
diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c
index 5593dd20721..5ee39e10c8d 100644
--- a/arch/arm/kernel/kprobes.c
+++ b/arch/arm/kernel/kprobes.c
@@ -274,7 +274,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
  * for kretprobe handlers which should normally be interested in r0 only
  * anyway.
  */
-static void __attribute__((naked)) __kprobes kretprobe_trampoline(void)
+void __naked __kprobes kretprobe_trampoline(void)
 {
 	__asm__ __volatile__ (
 		"stmdb	sp!, {r0 - r11}		\n\t"
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3934e265940..a5e9912e2d3 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -105,11 +105,13 @@ config ARCH_NO_VIRT_TO_BUS
 config PPC
 	bool
 	default y
+	select HAVE_DYNAMIC_FTRACE
+	select HAVE_FTRACE
 	select HAVE_IDE
-	select HAVE_OPROFILE
 	select HAVE_KPROBES
 	select HAVE_KRETPROBES
 	select HAVE_LMB
+	select HAVE_OPROFILE
 
 config EARLY_PRINTK
 	bool
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 2346d271fbf..f3f5e264143 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -12,6 +12,18 @@ CFLAGS_prom_init.o      += -fPIC
 CFLAGS_btext.o		+= -fPIC
 endif
 
+ifdef CONFIG_FTRACE
+# Do not trace early boot code
+CFLAGS_REMOVE_cputable.o = -pg
+CFLAGS_REMOVE_prom_init.o = -pg
+
+ifdef CONFIG_DYNAMIC_FTRACE
+# dynamic ftrace setup.
+CFLAGS_REMOVE_ftrace.o = -pg
+endif
+
+endif
+
 obj-y				:= cputable.o ptrace.o syscalls.o \
 				   irq.o align.o signal_32.o pmc.o vdso.o \
 				   init_task.o process.o systbl.o idle.o \
@@ -78,6 +90,8 @@ obj-$(CONFIG_KEXEC)		+= machine_kexec.o crash.o \
 obj-$(CONFIG_AUDIT)		+= audit.o
 obj64-$(CONFIG_AUDIT)		+= compat_audit.o
 
+obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o
+
 obj-$(CONFIG_8XX_MINIMAL_FPEMU) += softemu8xx.o
 
 ifneq ($(CONFIG_PPC_INDIRECT_IO),y)
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0c8614d9875..7231a708af0 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -30,6 +30,7 @@
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
+#include <asm/ftrace.h>
 
 #undef SHOW_SYSCALLS
 #undef SHOW_SYSCALLS_TASK
@@ -1035,3 +1036,129 @@ machine_check_in_rtas:
 	/* XXX load up BATs and panic */
 
 #endif /* CONFIG_PPC_RTAS */
+
+#ifdef CONFIG_FTRACE
+#ifdef CONFIG_DYNAMIC_FTRACE
+_GLOBAL(mcount)
+_GLOBAL(_mcount)
+	stwu	r1,-48(r1)
+	stw	r3, 12(r1)
+	stw	r4, 16(r1)
+	stw	r5, 20(r1)
+	stw	r6, 24(r1)
+	mflr	r3
+	stw	r7, 28(r1)
+	mfcr	r5
+	stw	r8, 32(r1)
+	stw	r9, 36(r1)
+	stw	r10,40(r1)
+	stw	r3, 44(r1)
+	stw	r5, 8(r1)
+	subi	r3, r3, MCOUNT_INSN_SIZE
+	.globl mcount_call
+mcount_call:
+	bl	ftrace_stub
+	nop
+	lwz	r6, 8(r1)
+	lwz	r0, 44(r1)
+	lwz	r3, 12(r1)
+	mtctr	r0
+	lwz	r4, 16(r1)
+	mtcr	r6
+	lwz	r5, 20(r1)
+	lwz	r6, 24(r1)
+	lwz	r0, 52(r1)
+	lwz	r7, 28(r1)
+	lwz	r8, 32(r1)
+	mtlr	r0
+	lwz	r9, 36(r1)
+	lwz	r10,40(r1)
+	addi	r1, r1, 48
+	bctr
+
+_GLOBAL(ftrace_caller)
+	/* Based off of objdump optput from glibc */
+	stwu	r1,-48(r1)
+	stw	r3, 12(r1)
+	stw	r4, 16(r1)
+	stw	r5, 20(r1)
+	stw	r6, 24(r1)
+	mflr	r3
+	lwz	r4, 52(r1)
+	mfcr	r5
+	stw	r7, 28(r1)
+	stw	r8, 32(r1)
+	stw	r9, 36(r1)
+	stw	r10,40(r1)
+	stw	r3, 44(r1)
+	stw	r5, 8(r1)
+	subi	r3, r3, MCOUNT_INSN_SIZE
+.globl ftrace_call
+ftrace_call:
+	bl	ftrace_stub
+	nop
+	lwz	r6, 8(r1)
+	lwz	r0, 44(r1)
+	lwz	r3, 12(r1)
+	mtctr	r0
+	lwz	r4, 16(r1)
+	mtcr	r6
+	lwz	r5, 20(r1)
+	lwz	r6, 24(r1)
+	lwz	r0, 52(r1)
+	lwz	r7, 28(r1)
+	lwz	r8, 32(r1)
+	mtlr	r0
+	lwz	r9, 36(r1)
+	lwz	r10,40(r1)
+	addi	r1, r1, 48
+	bctr
+#else
+_GLOBAL(mcount)
+_GLOBAL(_mcount)
+	stwu	r1,-48(r1)