Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
ftrace: fix current_tracer error return
tracing: fix a build error on alpha
ftrace: use a real variable for ftrace_nop in x86
tracing/ftrace: make boot tracer select the sched_switch tracer
tracepoint: check if the probe has been registered
asm-generic: define DIE_OOPS in asm-generic
trace: fix printk warning for u64
ftrace: warning in kernel/trace/ftrace.c
ftrace: fix build failure
ftrace, powerpc, sparc64, x86: remove notrace from arch ftrace file
ftrace: remove ftrace hash
ftrace: remove mcount set
ftrace: remove daemon
ftrace: disable dynamic ftrace for all archs that use daemon
ftrace: add ftrace warn on to disable ftrace
ftrace: only have ftrace_kill atomic
ftrace: use probe_kernel
ftrace: comment arch ftrace code
ftrace: return error on failed modified text.
ftrace: dynamic ftrace process only text section
...

Makefile

···
 KBUILD_AFLAGS	+= -gdwarf-2
 endif
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 KBUILD_CFLAGS	+= -pg
 endif
 

arch/arm/Kconfig

···
 	select HAVE_ARCH_KGDB
 	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)
+	select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
 	select HAVE_GENERIC_DMA_COHERENT
 	help
 	  The ARM series is a line of low-power-consumption RISC chip designs

arch/arm/boot/compressed/Makefile

···
 targets       := vmlinux vmlinux.lds piggy.gz piggy.o font.o font.c \
 		 head.o misc.o $(OBJS)
 
-ifeq ($(CONFIG_FTRACE),y)
+ifeq ($(CONFIG_FUNCTION_TRACER),y)
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
 endif

arch/arm/include/asm/ftrace.h

···
 #ifndef _ASM_ARM_FTRACE
 #define _ASM_ARM_FTRACE
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #define MCOUNT_ADDR		((long)(mcount))
 #define MCOUNT_INSN_SIZE	4 /* sizeof mcount call */
 

arch/arm/kernel/armksyms.c

···
 
 EXPORT_SYMBOL(copy_page);
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 EXPORT_SYMBOL(mcount);
 #endif

arch/arm/kernel/entry-common.S

···
 #undef CALL
 #define CALL(x) .long x
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 ENTRY(mcount)
 	stmdb sp!, {r0-r3, lr}
···
 ftrace_stub:
 	mov pc, lr
 
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 /*=============================================================================
  * SWI handler

arch/arm/kernel/ftrace.c

···
 	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)
 {

arch/powerpc/Kconfig

···
 config PPC
 	bool
 	default y
-	select HAVE_DYNAMIC_FTRACE
-	select HAVE_FTRACE
+	select HAVE_FUNCTION_TRACER
 	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select HAVE_IDE
 	select HAVE_IOREMAP_PROT

arch/powerpc/Makefile

···
 endif
 
 # Work around a gcc code-gen bug with -fno-omit-frame-pointer.
-ifeq ($(CONFIG_FTRACE),y)
+ifeq ($(CONFIG_FUNCTION_TRACER),y)
 KBUILD_CFLAGS		+= -mno-sched-epilog
 endif
 

arch/powerpc/include/asm/ftrace.h

···
 #ifndef _ASM_POWERPC_FTRACE
 #define _ASM_POWERPC_FTRACE
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #define MCOUNT_ADDR		((long)(_mcount))
 #define MCOUNT_INSN_SIZE	4 /* sizeof mcount call */
 

arch/powerpc/kernel/Makefile

···
 CFLAGS_btext.o		+= -fPIC
 endif
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 # Do not trace early boot code
 CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog
 CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog

arch/powerpc/kernel/entry_32.S

···
 
 #endif /* CONFIG_PPC_RTAS */
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 _GLOBAL(mcount)
 _GLOBAL(_mcount)

arch/powerpc/kernel/entry_64.S

···
 	mtlr    r0
         blr
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 _GLOBAL(mcount)
 _GLOBAL(_mcount)

arch/powerpc/kernel/ftrace.c

···
 #endif
 
 
-static unsigned int notrace ftrace_calc_offset(long ip, long addr)
+static unsigned int ftrace_calc_offset(long ip, long addr)
 {
 	return (int)(addr - ip);
 }
 
-notrace unsigned char *ftrace_nop_replace(void)
+unsigned char *ftrace_nop_replace(void)
 {
 	return (char *)&ftrace_nop;
 }
 
-notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
 {
 	static unsigned int op;
 
···
 # define _ASM_PTR	" .long "
 #endif
 
-notrace int
+int
 ftrace_modify_code(unsigned long ip, unsigned char *old_code,
 		   unsigned char *new_code)
 {
···
 	return faulted;
 }
 
-notrace int ftrace_update_ftrace_func(ftrace_func_t func)
+int ftrace_update_ftrace_func(ftrace_func_t func)
 {
 	unsigned long ip = (unsigned long)(&ftrace_call);
 	unsigned char old[MCOUNT_INSN_SIZE], *new;
···
 	ret = ftrace_modify_code(ip, old, new);
 
 	return ret;
-}
-
-notrace int ftrace_mcount_set(unsigned long *data)
-{
-	unsigned long ip = (long)(&mcount_call);
-	unsigned long *addr = data;
-	unsigned char old[MCOUNT_INSN_SIZE], *new;
-
-	/*
-	 * Replace the mcount stub with a pointer to the
-	 * ip recorder function.
-	 */
-	memcpy(old, &mcount_call, MCOUNT_INSN_SIZE);
-	new = ftrace_call_replace(ip, *addr);
-	*addr = ftrace_modify_code(ip, old, new);
-
-	return 0;
 }
 
 int __init ftrace_dyn_arch_init(void *data)

arch/powerpc/kernel/ppc_ksyms.c

···
 EXPORT_SYMBOL(sys_sigreturn);
 #endif
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 EXPORT_SYMBOL(_mcount);
 #endif
 

arch/powerpc/platforms/powermac/Makefile

···
 CFLAGS_bootx_init.o  		+= -fPIC
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 # Do not trace early boot code
 CFLAGS_REMOVE_bootx_init.o = -pg -mno-sched-epilog
 endif

arch/sparc64/Kconfig

···
 config SPARC64
 	bool
 	default y
-	select HAVE_DYNAMIC_FTRACE
-	select HAVE_FTRACE
+	select HAVE_FUNCTION_TRACER
 	select HAVE_IDE
 	select HAVE_LMB
 	select HAVE_ARCH_KGDB

arch/sparc64/Kconfig.debug

···
 
 config MCOUNT
 	bool
-	depends on STACK_DEBUG || FTRACE
+	depends on STACK_DEBUG || FUNCTION_TRACER
 	default y
 
 config FRAME_POINTER

arch/sparc64/kernel/Makefile

···
 EXTRA_AFLAGS := -ansi
 EXTRA_CFLAGS := -Werror
 
+CFLAGS_REMOVE_ftrace.o = -pg
+
 extra-y		:= head.o init_task.o vmlinux.lds
 
 obj-y		:= process.o setup.o cpu.o idprom.o reboot.o \

arch/sparc64/kernel/ftrace.c

···
 
 static const u32 ftrace_nop = 0x01000000;
 
-notrace unsigned char *ftrace_nop_replace(void)
+unsigned char *ftrace_nop_replace(void)
 {
 	return (char *)&ftrace_nop;
 }
 
-notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
 {
 	static u32 call;
 	s32 off;
···
 	return (unsigned char *) &call;
 }
 
-notrace int
+int
 ftrace_modify_code(unsigned long ip, unsigned char *old_code,
 		   unsigned char *new_code)
 {
···
 	return faulted;
 }
 
-notrace int ftrace_update_ftrace_func(ftrace_func_t func)
+int ftrace_update_ftrace_func(ftrace_func_t func)
 {
 	unsigned long ip = (unsigned long)(&ftrace_call);
 	unsigned char old[MCOUNT_INSN_SIZE], *new;
···
 	new = ftrace_call_replace(ip, (unsigned long)func);
 	return ftrace_modify_code(ip, old, new);
 }
-
-notrace int ftrace_mcount_set(unsigned long *data)
-{
-	unsigned long ip = (long)(&mcount_call);
-	unsigned long *addr = data;
-	unsigned char old[MCOUNT_INSN_SIZE], *new;
-
-	/*
-	 * Replace the mcount stub with a pointer to the
-	 * ip recorder function.
-	 */
-	memcpy(old, &mcount_call, MCOUNT_INSN_SIZE);
-	new = ftrace_call_replace(ip, *addr);
-	*addr = ftrace_modify_code(ip, old, new);
-
-	return 0;
-}
-
 
 int __init ftrace_dyn_arch_init(void *data)
 {

arch/sparc64/lib/mcount.S

···
 	 nop
 1:
 #endif
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 	mov		%o7, %o0
 	.globl		mcount_call
···
 	.size		_mcount,.-_mcount
 	.size		mcount,.-mcount
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 	.globl		ftrace_stub
 	.type		ftrace_stub,#function
 ftrace_stub:

arch/x86/Kconfig

···
 	select HAVE_KRETPROBES
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_DYNAMIC_FTRACE
-	select HAVE_FTRACE
+	select HAVE_FUNCTION_TRACER
 	select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
 	select HAVE_ARCH_KGDB if !X86_VOYAGER
 	select HAVE_ARCH_TRACEHOOK

arch/x86/include/asm/ftrace.h

···
 #ifndef _ASM_X86_FTRACE_H
 #define _ASM_X86_FTRACE_H
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #define MCOUNT_ADDR		((long)(mcount))
 #define MCOUNT_INSN_SIZE	5 /* sizeof mcount call */
 
···
 }
 #endif
 
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 #endif /* _ASM_X86_FTRACE_H */

arch/x86/kernel/Makefile

···
 
 CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE)
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 # Do not profile debug and lowlevel utilities
 CFLAGS_REMOVE_tsc.o = -pg
 CFLAGS_REMOVE_rtc.o = -pg
 CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
+CFLAGS_REMOVE_ftrace.o = -pg
 endif
 
 #

arch/x86/kernel/entry_32.S

···
 
 #endif	/* CONFIG_XEN */
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 
 ENTRY(mcount)
···
 	jmp ftrace_stub
 END(mcount)
 #endif /* CONFIG_DYNAMIC_FTRACE */
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 .section .rodata,"a"
 #include "syscall_table_32.S"

arch/x86/kernel/entry_64.S

···
 
 	.code64
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 #ifdef CONFIG_DYNAMIC_FTRACE
 ENTRY(mcount)
 	retq
···
 	jmp ftrace_stub
 END(mcount)
 #endif /* CONFIG_DYNAMIC_FTRACE */
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 #ifndef CONFIG_PREEMPT
 #define retint_kernel retint_restore_args

arch/x86/kernel/ftrace.c

···
 #include <asm/nops.h>
 
 
-/* Long is fine, even if it is only 4 bytes ;-) */
-static unsigned long *ftrace_nop;
+static unsigned char ftrace_nop[MCOUNT_INSN_SIZE];
 
 union ftrace_code_union {
 	char code[MCOUNT_INSN_SIZE];
···
 };
 
 
-static int notrace ftrace_calc_offset(long ip, long addr)
+static int ftrace_calc_offset(long ip, long addr)
 {
 	return (int)(addr - ip);
 }
 
-notrace unsigned char *ftrace_nop_replace(void)
+unsigned char *ftrace_nop_replace(void)
 {
-	return (char *)ftrace_nop;
+	return ftrace_nop;
 }
 
-notrace unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
+unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr)
 {
 	static union ftrace_code_union calc;
 
···
 	return calc.code;
 }
 
-notrace int
+int
 ftrace_modify_code(unsigned long ip, unsigned char *old_code,
 		   unsigned char *new_code)
 {
···
 	/*
 	 * Note: Due to modules and __init, code can
 	 *  disappear and change, we need to protect against faulting
-	 *  as well as code changing.
+	 *  as well as code changing. We do this by using the
+	 *  probe_kernel_* functions.
 	 *
 	 * No real locking needed, this code is run through
 	 * kstop_machine, or before SMP starts.
 	 */
-	if (__copy_from_user_inatomic(replaced, (char __user *)ip, MCOUNT_INSN_SIZE))
-		return 1;
 
+	/* read the text we want to modify */
+	if (probe_kernel_read(replaced, (void *)ip, MCOUNT_INSN_SIZE))
+		return -EFAULT;
+
+	/* Make sure it is what we expect it to be */
 	if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0)
-		return 2;
+		return -EINVAL;
 
-	WARN_ON_ONCE(__copy_to_user_inatomic((char __user *)ip, new_code,
-				    MCOUNT_INSN_SIZE));
+	/* replace the text with the new text */
+	if (probe_kernel_write((void *)ip, new_code, MCOUNT_INSN_SIZE))
+		return -EPERM;
 
 	sync_core();
 
 	return 0;
 }
 
-notrace int ftrace_update_ftrace_func(ftrace_func_t func)
+int ftrace_update_ftrace_func(ftrace_func_t func)
 {
 	unsigned long ip = (unsigned long)(&ftrace_call);
 	unsigned char old[MCOUNT_INSN_SIZE], *new;
···
 	ret = ftrace_modify_code(ip, old, new);
 
 	return ret;
-}
-
-notrace int ftrace_mcount_set(unsigned long *data)
-{
-	/* mcount is initialized as a nop */
-	*data = 0;
-	return 0;
 }
 
 int __init ftrace_dyn_arch_init(void *data)
···
 	 * TODO: check the cpuid to determine the best nop.
 	 */
 	asm volatile (
-		"jmp ftrace_test_jmp\n"
-		/* This code needs to stay around */
-		".section .text, \"ax\"\n"
 		"ftrace_test_jmp:"
 		"jmp ftrace_test_p6nop\n"
 		"nop\n"
···
 		"jmp 1f\n"
 		"ftrace_test_nop5:"
 		".byte 0x66,0x66,0x66,0x66,0x90\n"
-		"jmp 1f\n"
-		".previous\n"
 		"1:"
 		".section .fixup, \"ax\"\n"
 		"2:	movl $1, %0\n"
···
 	switch (faulted) {
 	case 0:
 		pr_info("ftrace: converting mcount calls to 0f 1f 44 00 00\n");
-		ftrace_nop = (unsigned long *)ftrace_test_p6nop;
+		memcpy(ftrace_nop, ftrace_test_p6nop, MCOUNT_INSN_SIZE);
 		break;
 	case 1:
 		pr_info("ftrace: converting mcount calls to 66 66 66 66 90\n");
-		ftrace_nop = (unsigned long *)ftrace_test_nop5;
+		memcpy(ftrace_nop, ftrace_test_nop5, MCOUNT_INSN_SIZE);
 		break;
 	case 2:
 		pr_info("ftrace: converting mcount calls to jmp . + 5\n");
-		ftrace_nop = (unsigned long *)ftrace_test_jmp;
+		memcpy(ftrace_nop, ftrace_test_jmp, MCOUNT_INSN_SIZE);
 		break;
 	}
 

arch/x86/kernel/i386_ksyms_32.c

···
 #include <asm/desc.h>
 #include <asm/ftrace.h>
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 /* mcount is defined in assembly */
 EXPORT_SYMBOL(mcount);
 #endif

arch/x86/kernel/x8664_ksyms_64.c

···
 #include <asm/desc.h>
 #include <asm/ftrace.h>
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 /* mcount is defined in assembly */
 EXPORT_SYMBOL(mcount);
 #endif

arch/x86/xen/Makefile

···
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 # Do not profile debug and lowlevel utilities
 CFLAGS_REMOVE_spinlock.o = -pg
 CFLAGS_REMOVE_time.o = -pg

include/asm-generic/kdebug.h

···
 
 enum die_val {
 	DIE_UNUSED,
+	DIE_OOPS=1
 };
 
 #endif /* _ASM_GENERIC_KDEBUG_H */

include/linux/ftrace.h

···
 #include <linux/types.h>
 #include <linux/kallsyms.h>
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 
 extern int ftrace_enabled;
 extern int
···
 
 extern void ftrace_stub(unsigned long a0, unsigned long a1);
 
-#else /* !CONFIG_FTRACE */
+#else /* !CONFIG_FUNCTION_TRACER */
 # define register_ftrace_function(ops) do { } while (0)
 # define unregister_ftrace_function(ops) do { } while (0)
 # define clear_ftrace_function(ops) do { } while (0)
-static inline void ftrace_kill_atomic(void) { }
-#endif /* CONFIG_FTRACE */
+static inline void ftrace_kill(void) { }
+#endif /* CONFIG_FUNCTION_TRACER */
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-# define FTRACE_HASHBITS	10
-# define FTRACE_HASHSIZE	(1<<FTRACE_HASHBITS)
 
 enum {
 	FTRACE_FL_FREE		= (1 << 0),
···
 };
 
 struct dyn_ftrace {
-	struct hlist_node node;
-	unsigned long	  ip; /* address of mcount call-site */
-	unsigned long	  flags;
+	struct list_head	list;
+	unsigned long		ip; /* address of mcount call-site */
+	unsigned long		flags;
 };
 
 int ftrace_force_update(void);
···
 extern unsigned char *ftrace_nop_replace(void);
 extern unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr);
 extern int ftrace_dyn_arch_init(void *data);
-extern int ftrace_mcount_set(unsigned long *data);
-extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code,
-			      unsigned char *new_code);
 extern int ftrace_update_ftrace_func(ftrace_func_t func);
 extern void ftrace_caller(void);
 extern void ftrace_call(void);
 extern void mcount_call(void);
+
+/**
+ * ftrace_modify_code - modify code segment
+ * @ip: the address of the code segment
+ * @old_code: the contents of what is expected to be there
+ * @new_code: the code to patch in
+ *
+ * This is a very sensitive operation and great care needs
+ * to be taken by the arch.  The operation should carefully
+ * read the location, check to see if what is read is indeed
+ * what we expect it to be, and then on success of the compare,
+ * it should write to the location.
+ *
+ * Return must be:
+ *  0 on success
+ *  -EFAULT on error reading the location
+ *  -EINVAL on a failed compare of the contents
+ *  -EPERM  on error writing to the location
+ * Any other value will be considered a failure.
+ */
+extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code,
+			      unsigned char *new_code);
 
 extern int skip_trace(unsigned long ip);
 
···
 
 /* totally disable ftrace - can not re-enable after this */
 void ftrace_kill(void);
-void ftrace_kill_atomic(void);
 
 static inline void tracer_disable(void)
 {
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 	ftrace_enabled = 0;
 #endif
 }
···
  */
 static inline int __ftrace_enabled_save(void)
 {
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 	int saved_ftrace_enabled = ftrace_enabled;
 	ftrace_enabled = 0;
 	return saved_ftrace_enabled;
···
 
 static inline void __ftrace_enabled_restore(int enabled)
 {
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 	ftrace_enabled = enabled;
 #endif
 }

kernel/Makefile

···
 
 CFLAGS_REMOVE_sched.o = -mno-spe
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 # Do not trace debug files and internal ftrace files
 CFLAGS_REMOVE_lockdep.o = -pg
 CFLAGS_REMOVE_lockdep_proc.o = -pg
···
 obj-$(CONFIG_TRACEPOINTS) += tracepoint.o
 obj-$(CONFIG_LATENCYTOP) += latencytop.o
 obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o
-obj-$(CONFIG_FTRACE) += trace/
+obj-$(CONFIG_FUNCTION_TRACER) += trace/
 obj-$(CONFIG_TRACING) += trace/
 obj-$(CONFIG_SMP) += sched_cpupri.o
 

kernel/sysctl.c

···
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec,
 	},
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 	{
 		.ctl_name	= CTL_UNNUMBERED,
 		.procname	= "ftrace_enabled",

kernel/trace/Kconfig

···
 #
-# Architectures that offer an FTRACE implementation should select HAVE_FTRACE:
+# Architectures that offer an FUNCTION_TRACER implementation should
+#  select HAVE_FUNCTION_TRACER:
 #
 
 config NOP_TRACER
 	bool
 
-config HAVE_FTRACE
+config HAVE_FUNCTION_TRACER
 	bool
 	select NOP_TRACER
 
···
 	select STACKTRACE
 	select TRACEPOINTS
 
-config FTRACE
+menu "Tracers"
+
+config FUNCTION_TRACER
 	bool "Kernel Function Tracer"
-	depends on HAVE_FTRACE
+	depends on HAVE_FUNCTION_TRACER
 	depends on DEBUG_KERNEL
 	select FRAME_POINTER
 	select TRACING
···
 	default n
 	depends on TRACE_IRQFLAGS_SUPPORT
 	depends on GENERIC_TIME
-	depends on HAVE_FTRACE
 	depends on DEBUG_KERNEL
 	select TRACE_IRQFLAGS
 	select TRACING
···
 	default n
 	depends on GENERIC_TIME
 	depends on PREEMPT
-	depends on HAVE_FTRACE
 	depends on DEBUG_KERNEL
 	select TRACING
 	select TRACER_MAX_TRACE
···
 
 config SCHED_TRACER
 	bool "Scheduling Latency Tracer"
-	depends on HAVE_FTRACE
 	depends on DEBUG_KERNEL
 	select TRACING
 	select CONTEXT_SWITCH_TRACER
···
 
 config CONTEXT_SWITCH_TRACER
 	bool "Trace process context switches"
-	depends on HAVE_FTRACE
 	depends on DEBUG_KERNEL
 	select TRACING
 	select MARKERS
···
 
 config BOOT_TRACER
 	bool "Trace boot initcalls"
-	depends on HAVE_FTRACE
 	depends on DEBUG_KERNEL
 	select TRACING
+	select CONTEXT_SWITCH_TRACER
 	help
 	  This tracer helps developers to optimize boot times: it records
 	  the timings of the initcalls and traces key events and the identity
···
 
 config STACK_TRACER
 	bool "Trace max stack"
-	depends on HAVE_FTRACE
+	depends on HAVE_FUNCTION_TRACER
 	depends on DEBUG_KERNEL
-	select FTRACE
+	select FUNCTION_TRACER
 	select STACKTRACE
 	help
 	  This special tracer records the maximum stack footprint of the
···
 
 config DYNAMIC_FTRACE
 	bool "enable/disable ftrace tracepoints dynamically"
-	depends on FTRACE
+	depends on FUNCTION_TRACER
 	depends on HAVE_DYNAMIC_FTRACE
 	depends on DEBUG_KERNEL
 	default y
···
 	 with a No-Op instruction) as they are called. A table is
 	 created to dynamically enable them again.
 
-	 This way a CONFIG_FTRACE kernel is slightly larger, but otherwise
+	 This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but otherwise
 	 has native performance as long as no tracing is active.
 
 	 The changes to the code are done by a kernel thread that
···
 	  a series of tests are made to verify that the tracer is
 	  functioning properly. It will do tests on all the configured
 	  tracers of ftrace.
+
+endmenu

kernel/trace/Makefile

···
 
 # Do not instrument the tracer itself:
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
 
···
 obj-y += trace_selftest_dynamic.o
 endif
 
-obj-$(CONFIG_FTRACE) += libftrace.o
+obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o
 obj-$(CONFIG_RING_BUFFER) += ring_buffer.o
 
 obj-$(CONFIG_TRACING) += trace.o
 obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
 obj-$(CONFIG_SYSPROF_TRACER) += trace_sysprof.o
-obj-$(CONFIG_FTRACE) += trace_functions.o
+obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o
 obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
 obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
 obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o

kernel/trace/ftrace.c

···
 #include <linux/ftrace.h>
 #include <linux/sysctl.h>
 #include <linux/ctype.h>
-#include <linux/hash.h>
 #include <linux/list.h>
 
 #include <asm/ftrace.h>
 
 #include "trace.h"
+
+#define FTRACE_WARN_ON(cond)			\
+	do {					\
+		if (WARN_ON(cond))		\
+			ftrace_kill();		\
+	} while (0)
+
+#define FTRACE_WARN_ON_ONCE(cond)		\
+	do {					\
+		if (WARN_ON_ONCE(cond))		\
+			ftrace_kill();		\
+	} while (0)
 
 /* ftrace_enabled is a method to turn ftrace on or off */
 int ftrace_enabled __read_mostly;
···
 }
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-
 #ifndef CONFIG_FTRACE_MCOUNT_RECORD
-/*
- * The hash lock is only needed when the recording of the mcount
- * callers are dynamic. That is, by the caller themselves and
- * not recorded via the compilation.
- */
-static DEFINE_SPINLOCK(ftrace_hash_lock);
-#define ftrace_hash_lock(flags)	  spin_lock_irqsave(&ftrace_hash_lock, flags)
-#define ftrace_hash_unlock(flags) \
-			spin_unlock_irqrestore(&ftrace_hash_lock, flags)
-#else
-/* This is protected via the ftrace_lock with MCOUNT_RECORD. */
-#define ftrace_hash_lock(flags)   do { (void)(flags); } while (0)
-#define ftrace_hash_unlock(flags) do { } while(0)
+# error Dynamic ftrace depends on MCOUNT_RECORD
 #endif
 
 /*
···
  * it instead.
  */
 static unsigned long mcount_addr = MCOUNT_ADDR;
-
-static struct task_struct *ftraced_task;
 
 enum {
 	FTRACE_ENABLE_CALLS		= (1 << 0),
···
 
 static int ftrace_filtered;
 static int tracing_on;
-static int frozen_record_count;
 
-static struct hlist_head ftrace_hash[FTRACE_HASHSIZE];
+static LIST_HEAD(ftrace_new_addrs);
 
-static DEFINE_PER_CPU(int, ftrace_shutdown_disable_cpu);
-
-static DEFINE_MUTEX(ftraced_lock);
 static DEFINE_MUTEX(ftrace_regex_lock);
 
 struct ftrace_page {
···
 static struct ftrace_page	*ftrace_pages_start;
 static struct ftrace_page	*ftrace_pages;
 
-static int ftraced_trigger;
-static int ftraced_suspend;
-static int ftraced_stop;
-
-static int ftrace_record_suspend;
-
 static struct dyn_ftrace *ftrace_free_records;
 
 
 #ifdef CONFIG_KPROBES
+
+static int frozen_record_count;
+
 static inline void freeze_record(struct dyn_ftrace *rec)
 {
 	if (!(rec->flags & FTRACE_FL_FROZEN)) {
···
 # define unfreeze_record(rec)			({ 0; })
 # define record_frozen(rec)			({ 0; })
 #endif /* CONFIG_KPROBES */
-
-int skip_trace(unsigned long ip)
-{
-	unsigned long fl;
-	struct dyn_ftrace *rec;
-	struct hlist_node *t;
-	struct hlist_head *head;
-
-	if (frozen_record_count == 0)
-		return 0;
-
-	head = &ftrace_hash[hash_long(ip, FTRACE_HASHBITS)];
-	hlist_for_each_entry_rcu(rec, t, head, node) {
-		if (rec->ip == ip) {
-			if (record_frozen(rec)) {
-				if (rec->flags & FTRACE_FL_FAILED)
-					return 1;
-
-				if (!(rec->flags & FTRACE_FL_CONVERTED))
-					return 1;
-
-				if (!tracing_on || !ftrace_enabled)
-					return 1;
-
-				if (ftrace_filtered) {
-					fl = rec->flags & (FTRACE_FL_FILTER |
-							   FTRACE_FL_NOTRACE);
-					if (!fl || (fl & FTRACE_FL_NOTRACE))
-						return 1;
-				}
-			}
-			break;
-		}
-	}
-
-	return 0;
-}
-
-static inline int
-ftrace_ip_in_hash(unsigned long ip, unsigned long key)
-{
-	struct dyn_ftrace *p;
-	struct hlist_node *t;
-	int found = 0;
-
-	hlist_for_each_entry_rcu(p, t, &ftrace_hash[key], node) {
-		if (p->ip == ip) {
-			found = 1;
-			break;
-		}
-	}
-
-	return found;
-}
-
-static inline void
-ftrace_add_hash(struct dyn_ftrace *node, unsigned long key)
-{
-	hlist_add_head_rcu(&node->node, &ftrace_hash[key]);
-}
-
-/* called from kstop_machine */
-static inline void ftrace_del_hash(struct dyn_ftrace *node)
-{
-	hlist_del(&node->node);
-}
 
 static void ftrace_free_rec(struct dyn_ftrace *rec)
 {
···
 		}
 	}
 	spin_unlock(&ftrace_lock);
-
 }
 
 static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
···
 		rec = ftrace_free_records;
 
 		if (unlikely(!(rec->flags & FTRACE_FL_FREE))) {
-			WARN_ON_ONCE(1);
+			FTRACE_WARN_ON_ONCE(1);
 			ftrace_free_records = NULL;
-			ftrace_disabled = 1;
-			ftrace_enabled = 0;
 			return NULL;
 		}
 
···
 	}
 
 	if (ftrace_pages->index == ENTRIES_PER_PAGE) {
-		if (!ftrace_pages->next)
-			return NULL;
+		if (!ftrace_pages->next) {
+			/* allocate another page */
+			ftrace_pages->next =
+				(void *)get_zeroed_page(GFP_KERNEL);
+			if (!ftrace_pages->next)
+				return NULL;
+		}
 		ftrace_pages = ftrace_pages->next;
 	}
 
 	return &ftrace_pages->records[ftrace_pages->index++];
 }
 
-static void
+static struct dyn_ftrace *
 ftrace_record_ip(unsigned long ip)
 {
-	struct dyn_ftrace *node;
-	unsigned long flags;
-	unsigned long key;
-	int resched;
-	int cpu;
+	struct dyn_ftrace *rec;
 
 	if (!ftrace_enabled || ftrace_disabled)
-		return;
+		return NULL;
 
-	resched = need_resched();
-	preempt_disable_notrace();
+	rec = ftrace_alloc_dyn_node(ip);
+	if (!rec)
+		return NULL;
 
-	/*
-	 * We simply need to protect against recursion.
-	 * Use the the raw version of smp_processor_id and not
-	 * __get_cpu_var which can call debug hooks that can
-	 * cause a recursive crash here.
-	 */
-	cpu = raw_smp_processor_id();
-	per_cpu(ftrace_shutdown_disable_cpu, cpu)++;
-	if (per_cpu(ftrace_shutdown_disable_cpu, cpu) != 1)
-		goto out;
+	rec->ip = ip;
 
-	if (unlikely(ftrace_record_suspend))
-		goto out;
+	list_add(&rec->list, &ftrace_new_addrs);
 
-	key = hash_long(ip, FTRACE_HASHBITS);
-
-	WARN_ON_ONCE(key >= FTRACE_HASHSIZE);
-
-	if (ftrace_ip_in_hash(ip, key))
-		goto out;
-
-	ftrace_hash_lock(flags);
-
-	/* This ip may have hit the hash before the lock */
-	if (ftrace_ip_in_hash(ip, key))
-		goto out_unlock;
-
-	node = ftrace_alloc_dyn_node(ip);
-	if (!node)
-		goto out_unlock;
-
-	node->ip = ip;
-
-	ftrace_add_hash(node, key);
-
-	ftraced_trigger = 1;
-
- out_unlock:
-	ftrace_hash_unlock(flags);
- out:
-	per_cpu(ftrace_shutdown_disable_cpu, cpu)--;
-
-	/* prevent recursion with scheduler */
-	if (resched)
-		preempt_enable_no_resched_notrace();
-	else
-		preempt_enable_notrace();
+	return rec;
 }
 
 #define FTRACE_ADDR ((long)(ftrace_caller))
···
 				rec->flags |= FTRACE_FL_FAILED;
 				if ((system_state == SYSTEM_BOOTING) ||
 				    !core_kernel_text(rec->ip)) {
-					ftrace_del_hash(rec);
 					ftrace_free_rec(rec);
 				}
 			}
 		}
 	}
-}
-
-static void ftrace_shutdown_replenish(void)
-{
-	if (ftrace_pages->next)
-		return;
-
-	/* allocate another page */
-	ftrace_pages->next = (void *)get_zeroed_page(GFP_KERNEL);
 }
 
 static void print_ip_ins(const char *fmt, unsigned char *p)
···
 {
 	unsigned long ip;
 	unsigned char *nop, *call;
-	int failed;
+	int ret;
 
 	ip = rec->ip;
 
 	nop = ftrace_nop_replace();
 	call = ftrace_call_replace(ip, mcount_addr);
 
-	failed = ftrace_modify_code(ip, call, nop);
-	if (failed) {
-		switch (failed) {
-		case 1:
-			WARN_ON_ONCE(1);
+	ret = ftrace_modify_code(ip, call, nop);
+	if (ret) {
+		switch (ret) {
+		case -EFAULT:
+			FTRACE_WARN_ON_ONCE(1);
 			pr_info("ftrace faulted on modifying ");
 			print_ip_sym(ip);
 			break;
-		case 2:
-			WARN_ON_ONCE(1);
+		case -EINVAL:
+			FTRACE_WARN_ON_ONCE(1);
 			pr_info("ftrace failed to modify ");
 			print_ip_sym(ip);
 			print_ip_ins(" expected: ", call);
···
 			print_ip_ins(" replace: ", nop);
 			printk(KERN_CONT "\n");
 			break;
+		case -EPERM:
+			FTRACE_WARN_ON_ONCE(1);
+			pr_info("ftrace faulted on writing ");
+			print_ip_sym(ip);
+			break;
+		default:
+			FTRACE_WARN_ON_ONCE(1);
+			pr_info("ftrace faulted on unknown error ");
+			print_ip_sym(ip);
 		}
 
 		rec->flags |= FTRACE_FL_FAILED;
···
 	return 1;
 }
 
-static int __ftrace_update_code(void *ignore);
-
 static int __ftrace_modify_code(void *data)
 {
-	unsigned long addr;
 	int *command = data;
 
 	if (*command & FTRACE_ENABLE_CALLS) {
-		/*
-		 * Update any recorded ips now that we have the
-		 * machine stopped
-		 */
-		__ftrace_update_code(NULL);
 		ftrace_replace_code(1);
 		tracing_on = 1;
 	} else if (*command & FTRACE_DISABLE_CALLS) {
···
 	if (*command & FTRACE_UPDATE_TRACE_FUNC)
 		ftrace_update_ftrace_func(ftrace_trace_function);
 
-	if (*command & FTRACE_ENABLE_MCOUNT) {
-		addr = (unsigned long)ftrace_record_ip;
-		ftrace_mcount_set(&addr);
-	} else if (*command & FTRACE_DISABLE_MCOUNT) {
-		addr = (unsigned long)ftrace_stub;
-		ftrace_mcount_set(&addr);
-	}
-
 	return 0;
 }
 
···
 	stop_machine(__ftrace_modify_code, &command, NULL);
 }
 
-void ftrace_disable_daemon(void)
-{
-	/* Stop the daemon from calling kstop_machine */
-	mutex_lock(&ftraced_lock);
-	ftraced_stop = 1;
-	mutex_unlock(&ftraced_lock);
-
-	ftrace_force_update();
-}
-
-void ftrace_enable_daemon(void)
-{
-	mutex_lock(&ftraced_lock);
-	ftraced_stop = 0;
-	mutex_unlock(&ftraced_lock);
-
-	ftrace_force_update();
-}
-
 static ftrace_func_t saved_ftrace_func;
+static int ftrace_start;
+static DEFINE_MUTEX(ftrace_start_lock);
 
 static void ftrace_startup(void)
 {
···
 	if (unlikely(ftrace_disabled))
 		return;
 
-	mutex_lock(&ftraced_lock);
-	ftraced_suspend++;
-	if (ftraced_suspend == 1)
+	mutex_lock(&ftrace_start_lock);
+	ftrace_start++;
+	if (ftrace_start == 1)
 		command |= FTRACE_ENABLE_CALLS;
 
 	if (saved_ftrace_func != ftrace_trace_function) {
···
 
 	ftrace_run_update_code(command);
  out:
-	mutex_unlock(&ftraced_lock);
+	mutex_unlock(&ftrace_start_lock);
 }
 
 static void ftrace_shutdown(void)
···
 	if (unlikely(ftrace_disabled))
 		return;
 
-	mutex_lock(&ftraced_lock);
-	ftraced_suspend--;
-	if (!ftraced_suspend)
+	mutex_lock(&ftrace_start_lock);
+	ftrace_start--;
+	if (!ftrace_start)
 		command |= FTRACE_DISABLE_CALLS;
 
 	if (saved_ftrace_func != ftrace_trace_function) {
···
 
 	ftrace_run_update_code(command);
  out:
-	mutex_unlock(&ftraced_lock);
+	mutex_unlock(&ftrace_start_lock);
 }
 
 static void ftrace_startup_sysctl(void)
···
 	if (unlikely(ftrace_disabled))
 		return;
 
-	mutex_lock(&ftraced_lock);
+	mutex_lock(&ftrace_start_lock);
 	/* Force update next time */
 	saved_ftrace_func = NULL;
-	/* ftraced_suspend is true if we want ftrace running */
-	if (ftraced_suspend)
+	/* ftrace_start is true if we want ftrace running */
+	if (ftrace_start)
 		command |= FTRACE_ENABLE_CALLS;
 
 	ftrace_run_update_code(command);
-	mutex_unlock(&ftraced_lock);
+	mutex_unlock(&ftrace_start_lock);
 }
 
 static void ftrace_shutdown_sysctl(void)
···
 	if (unlikely(ftrace_disabled))
 		return;
 
-	mutex_lock(&ftraced_lock);
-	/* ftraced_suspend is true if ftrace is running */
-	if (ftraced_suspend)
+	mutex_lock(&ftrace_start_lock);
+	/* ftrace_start is true if ftrace is running */
+	if (ftrace_start)
 		command |= FTRACE_DISABLE_CALLS;
 
 	ftrace_run_update_code(command);
-	mutex_unlock(&ftraced_lock);
+	mutex_unlock(&ftrace_start_lock);
 }
 
 static cycle_t		ftrace_update_time;
 static unsigned long	ftrace_update_cnt;
 unsigned long		ftrace_update_tot_cnt;
 
-static int __ftrace_update_code(void *ignore)
+static int ftrace_update_code(void)
 {
-	int i, save_ftrace_enabled;
+	struct dyn_ftrace *p, *t;
 	cycle_t start, stop;
-	struct dyn_ftrace *p;
-	struct hlist_node *t, *n;
-	struct hlist_head *head, temp_list;
-
-	/* Don't be recording funcs now */
-	ftrace_record_suspend++;
-	save_ftrace_enabled = ftrace_enabled;
-	ftrace_enabled = 0;
 
 	start = ftrace_now(raw_smp_processor_id());
 	ftrace_update_cnt = 0;
 
-	/* No locks needed, the machine is stopped! */
-	for (i = 0; i < FTRACE_HASHSIZE; i++) {
-		INIT_HLIST_HEAD(&temp_list);
-		head = &ftrace_hash[i];
+	list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) {
 
-		/* all CPUS are stopped, we are safe to modify code */
-		hlist_for_each_entry_safe(p, t, n, head, node) {
-			/* Skip over failed records which have not been
-			 * freed. */
-			if (p->flags & FTRACE_FL_FAILED)
-				continue;
+		/* If something went wrong, bail without enabling anything */
+		if (unlikely(ftrace_disabled))
+			return -1;
 
-			/* Unconverted records are always at the head of the
-			 * hash bucket. Once we encounter a converted record,
-			 * simply skip over to the next bucket. Saves ftraced
-			 * some processor cycles (ftrace does its bid for
-			 * global warming :-p ). */
-			if (p->flags & (FTRACE_FL_CONVERTED))
-				break;
+		list_del_init(&p->list);
 
-			/* Ignore updates to this record's mcount site.
-			 * Reintroduce this record at the head of this
-			 * bucket to attempt to "convert" it again if
-			 * the kprobe on it is unregistered before the
-			 * next run. */
-			if (get_kprobe((void *)p->ip)) {
-				ftrace_del_hash(p);
-				INIT_HLIST_NODE(&p->node);
-				hlist_add_head(&p->node, &temp_list);
-				freeze_record(p);
-				continue;
-			} else {
-				unfreeze_record(p);
-			}
-
-			/* convert record (i.e, patch mcount-call with NOP) */
-			if (ftrace_code_disable(p)) {
-				p->flags |= FTRACE_FL_CONVERTED;
-				ftrace_update_cnt++;
-			} else {
-				if ((system_state == SYSTEM_BOOTING) ||
-				    !core_kernel_text(p->ip)) {
-					ftrace_del_hash(p);
-					ftrace_free_rec(p);
-				}
-			}
-		}
-
-		hlist_for_each_entry_safe(p, t, n, &temp_list, node) {
-			hlist_del(&p->node);
-			INIT_HLIST_NODE(&p->node);
-			hlist_add_head(&p->node, head);
-		}
+		/* convert record (i.e, patch mcount-call with NOP) */
+		if (ftrace_code_disable(p)) {
+			p->flags |= FTRACE_FL_CONVERTED;
+			ftrace_update_cnt++;
+		} else
+			ftrace_free_rec(p);
 	}
 
 	stop = ftrace_now(raw_smp_processor_id());
 	ftrace_update_time = stop - start;
 	ftrace_update_tot_cnt += ftrace_update_cnt;
-	ftraced_trigger = 0;
-
-	ftrace_enabled = save_ftrace_enabled;
-	ftrace_record_suspend--;
 
 	return 0;
-}
-
-static int ftrace_update_code(void)
-{
-	if (unlikely(ftrace_disabled) ||
-	    !ftrace_enabled || !ftraced_trigger)
-		return 0;
-
-	stop_machine(__ftrace_update_code, NULL, NULL);
-
-	return 1;
 }
 
 static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
···
 	pg = ftrace_pages = ftrace_pages_start;
 
 	cnt = num_to_init / ENTRIES_PER_PAGE;
-	pr_info("ftrace: allocating %ld hash entries in %d pages\n",
+	pr_info("ftrace: allocating %ld entries in %d pages\n",
 		num_to_init, cnt);
 
 	for (i = 0; i < cnt; i++) {
···
 	}
 
 	mutex_lock(&ftrace_sysctl_lock);
-	mutex_lock(&ftraced_lock);
-	if (iter->filtered && ftraced_suspend && ftrace_enabled)
+	mutex_lock(&ftrace_start_lock);
+	if (iter->filtered && ftrace_start && ftrace_enabled)
 		ftrace_run_update_code(FTRACE_ENABLE_CALLS);
-	mutex_unlock(&ftraced_lock);
+	mutex_unlock(&ftrace_start_lock);
 	mutex_unlock(&ftrace_sysctl_lock);
 
 	kfree(iter);
···
 ftrace_notrace_release(struct inode *inode, struct file *file)
 {
 	return ftrace_regex_release(inode, file, 0);
-}
-
-static ssize_t
-ftraced_read(struct file *filp, char __user *ubuf,
-		     size_t cnt, loff_t *ppos)
-{
-	/* don't worry about races */
-	char *buf = ftraced_stop ? "disabled\n" : "enabled\n";
-	int r = strlen(buf);
-
-	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-}
-
-static ssize_t
-ftraced_write(struct file *filp, const char __user *ubuf,
-		      size_t cnt, loff_t *ppos)
-{
-	char buf[64];
-	long val;
-	int ret;
-
-	if (cnt >= sizeof(buf))
-		return -EINVAL;
-
-	if (copy_from_user(&buf, ubuf, cnt))
-		return -EFAULT;
-
-	if (strncmp(buf, "enable", 6) == 0)
-		val = 1;
-	else if (strncmp(buf, "disable", 7) == 0)
-		val = 0;
-	else {
-		buf[cnt] = 0;
-
-		ret = strict_strtoul(buf, 10, &val);
-		if (ret < 0)
-			return ret;
-
-		val = !!val;
-	}
-
-	if (val)
-		ftrace_enable_daemon();
-	else
-		ftrace_disable_daemon();
-
-	filp->f_pos += cnt;
-
-	return cnt;
 }
 
 static struct file_operations ftrace_avail_fops = {
···
 	.release = ftrace_notrace_release,
 };
 
-static struct file_operations ftraced_fops = {
-	.open = tracing_open_generic,
-	.read = ftraced_read,
-	.write = ftraced_write,
-};
-
-/**
- * ftrace_force_update - force an update to all recording ftrace functions
- */
-int ftrace_force_update(void)
-{
-	int ret = 0;
-
-	if (unlikely(ftrace_disabled))
-		return -ENODEV;
-
-	mutex_lock(&ftrace_sysctl_lock);
-	mutex_lock(&ftraced_lock);
-
-	/*
-	 * If ftraced_trigger is not set, then there is nothing
-	 * to update.
-	 */
-	if (ftraced_trigger && !ftrace_update_code())
-		ret = -EBUSY;
-
-	mutex_unlock(&ftraced_lock);
-	mutex_unlock(&ftrace_sysctl_lock);
-
-	return ret;
-}
-
-static void ftrace_force_shutdown(void)
-{
-	struct task_struct *task;
-	int command = FTRACE_DISABLE_CALLS | FTRACE_UPDATE_TRACE_FUNC;
-
-	mutex_lock(&ftraced_lock);
-	task = ftraced_task;
-	ftraced_task = NULL;
-	ftraced_suspend = -1;
-	ftrace_run_update_code(command);
-	mutex_unlock(&ftraced_lock);
-
-	if (task)
-		kthread_stop(task);
-}
-
 static __init int ftrace_init_debugfs(void)
 {
 	struct dentry *d_tracer;
···
 		pr_warning("Could not create debugfs "
 			   "'set_ftrace_notrace' entry\n");
 
-	entry = debugfs_create_file("ftraced_enabled", 0644, d_tracer,
-				    NULL, &ftraced_fops);
-	if (!entry)
-		pr_warning("Could not create debugfs "
-			   "'ftraced_enabled' entry\n");
 	return 0;
 }
 
 fs_initcall(ftrace_init_debugfs);
 
-#ifdef CONFIG_FTRACE_MCOUNT_RECORD
 static int ftrace_convert_nops(unsigned long *start,
 			       unsigned long *end)
 {
···
 	unsigned long addr;
 	unsigned long flags;
 
+	mutex_lock(&ftrace_start_lock);
 	p = start;
 	while (p < end) {
 		addr = ftrace_call_adjust(*p++);
-		/* should not be called from interrupt context */
-		spin_lock(&ftrace_lock);
 		ftrace_record_ip(addr);
-		spin_unlock(&ftrace_lock);
-		ftrace_shutdown_replenish();
 	}
 
-	/* p is ignored */
+	/* disable interrupts to prevent kstop machine */
 	local_irq_save(flags);
-	__ftrace_update_code(p);
+	ftrace_update_code();
 	local_irq_restore(flags);
+	mutex_unlock(&ftrace_start_lock);
 
 	return 0;
 }
···
  failed:
 	ftrace_disabled = 1;
 }
-#else /* CONFIG_FTRACE_MCOUNT_RECORD */
-static int ftraced(void *ignore)
-{
-	unsigned long usecs;
-
-	while (!kthread_should_stop()) {
-
-		set_current_state(TASK_INTERRUPTIBLE);
-
-		/* check once a second */
-		schedule_timeout(HZ);
-
-		if (unlikely(ftrace_disabled))
-			continue;
-
-		mutex_lock(&ftrace_sysctl_lock);
-		mutex_lock(&ftraced_lock);
-		if (!ftraced_suspend && !ftraced_stop &&
-		    ftrace_update_code()) {
-			usecs = nsecs_to_usecs(ftrace_update_time);
-			if (ftrace_update_tot_cnt > 100000) {
-				ftrace_update_tot_cnt = 0;
-				pr_info("hm, dftrace overflow: %lu change%s"
-					" (%lu total) in %lu usec%s\n",
-					ftrace_update_cnt,
-					ftrace_update_cnt != 1 ? "s" : "",
-					ftrace_update_tot_cnt,
-					usecs, usecs != 1 ? "s" : "");
-				ftrace_disabled = 1;
-				WARN_ON_ONCE(1);
-			}
-		}
-		mutex_unlock(&ftraced_lock);
-		mutex_unlock(&ftrace_sysctl_lock);
-
-		ftrace_shutdown_replenish();
-	}
-	__set_current_state(TASK_RUNNING);
-	return 0;
-}
-
-static int __init ftrace_dynamic_init(void)
-{
-	struct task_struct *p;
-	unsigned long addr;
-	int ret;
-
-	addr = (unsigned long)ftrace_record_ip;
-
-	stop_machine(ftrace_dyn_arch_init, &addr, NULL);
-
-	/* ftrace_dyn_arch_init places the return code in addr */
-	if (addr) {
-		ret = (int)addr;
-		goto failed;
-	}
-
-	ret = ftrace_dyn_table_alloc(NR_TO_INIT);
-	if (ret)
-		goto failed;
-
-	p = kthread_run(ftraced, NULL, "ftraced");
-	if (IS_ERR(p)) {
-		ret = -1;
-		goto failed;
-	}
-
-	last_ftrace_enabled = ftrace_enabled = 1;
-	ftraced_task = p;
-
-	return 0;
-
- failed:
-	ftrace_disabled = 1;
-	return ret;
-}
-
-core_initcall(ftrace_dynamic_init);
-#endif /* CONFIG_FTRACE_MCOUNT_RECORD */
 
 #else
 # define ftrace_startup()		do { } while (0)
 # define ftrace_shutdown()		do { } while (0)
 # define ftrace_startup_sysctl()	do { } while (0)
 # define ftrace_shutdown_sysctl()	do { } while (0)
-# define ftrace_force_shutdown()	do { } while (0)
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 /**
- * ftrace_kill_atomic - kill ftrace from critical sections
+ * ftrace_kill - kill ftrace
  *
  * This function should be used by panic code. It stops ftrace
  * but in a not so nice way. If you need to simply kill ftrace
  * from a non-atomic section, use ftrace_kill.
  */
-void ftrace_kill_atomic(void)
-{
-	ftrace_disabled = 1;
-	ftrace_enabled = 0;
-#ifdef CONFIG_DYNAMIC_FTRACE
-	ftraced_suspend = -1;
-#endif
-	clear_ftrace_function();
-}
-
-/**
- * ftrace_kill - totally shutdown ftrace
- *
- * This is a safety measure. If something was detected that seems
- * wrong, calling this function will keep ftrace from doing
- * any more modifications, and updates.
- * used when something went wrong.
- */
 void ftrace_kill(void)
 {
-	mutex_lock(&ftrace_sysctl_lock);
 	ftrace_disabled = 1;
 	ftrace_enabled = 0;
-
 	clear_ftrace_function();
-	mutex_unlock(&ftrace_sysctl_lock);
-
-	/* Try to totally disable ftrace */
-	ftrace_force_shutdown();
 }
 
 /**
···
 	mutex_unlock(&ftrace_sysctl_lock);
 	return ret;
 }
+

kernel/trace/ring_buffer.c

···
 static inline void free_buffer_page(struct buffer_page *bpage)
 {
 	if (bpage->page)
-		__free_page(bpage->page);
+		free_page((unsigned long)bpage->page);
 	kfree(bpage);
 }
 
···
 	if (unlikely(*delta > (1ULL << 59) && !once++)) {
 		printk(KERN_WARNING "Delta way too big! %llu"
 		       " ts=%llu write stamp = %llu\n",
-		       *delta, *ts, cpu_buffer->write_stamp);
+		       (unsigned long long)*delta,
+		       (unsigned long long)*ts,
+		       (unsigned long long)cpu_buffer->write_stamp);
 		WARN_ON(1);
 	}
 

kernel/trace/trace.c

···
 
 #include <linux/stacktrace.h>
 #include <linux/ring_buffer.h>
+#include <linux/irqflags.h>
 
 #include "trace.h"
 
···
 	preempt_enable_notrace();
 }
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 static void
 function_trace_call(unsigned long ip, unsigned long parent_ip)
 {
···
 	int pc;
 
 	if (unlikely(!ftrace_function_enabled))
-		return;
-
-	if (skip_trace(ip))
 		return;
 
 	pc = preempt_count();
···
 	int i;
 	size_t ret;
 
+	ret = cnt;
+
 	if (cnt > max_tracer_type_len)
 		cnt = max_tracer_type_len;
-	ret = cnt;
 
 	if (copy_from_user(&buf, ubuf, cnt))
 		return -EFAULT;
···
  out:
 	mutex_unlock(&trace_types_lock);
 
-	if (ret == cnt)
-		filp->f_pos += cnt;
+	if (ret > 0)
+		filp->f_pos += ret;
 
 	return ret;
 }
···
 	dump_ran = 1;
 
 	/* No turning back! */
-	ftrace_kill_atomic();
+	ftrace_kill();
 
 	for_each_tracing_cpu(cpu) {
 		atomic_inc(&global_trace.data[cpu]->disabled);

kernel/trace/trace.h

···
 
 extern cycle_t ftrace_now(int cpu);
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 void tracing_start_function_trace(void);
 void tracing_stop_function_trace(void);
 #else

kernel/trace/trace_functions.c

···
 
 static struct tracer function_trace __read_mostly =
 {
-	.name	     = "ftrace",
+	.name	     = "function",
 	.init	     = function_trace_init,
 	.reset	     = function_trace_reset,
 	.ctrl_update = function_trace_ctrl_update,

kernel/trace/trace_irqsoff.c

···
  */
 static __cacheline_aligned_in_smp	unsigned long max_sequence;
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 /*
  * irqsoff uses its own tracer function to keep the overhead down:
  */
···
 {
 	.func = irqsoff_tracer_call,
 };
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 /*
  * Should this new latency be reported/recorded?

kernel/trace/trace_sched_wakeup.c

···
 
 static void __wakeup_reset(struct trace_array *tr);
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 /*
  * irqsoff uses its own tracer function to keep the overhead down:
  */
···
 {
 	.func = wakeup_tracer_call,
 };
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 /*
  * Should this new latency be reported/recorded?

kernel/trace/trace_selftest.c

···
 	return ret;
 }
 
-#ifdef CONFIG_FTRACE
+#ifdef CONFIG_FUNCTION_TRACER
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 
···
 
 	/* passed in by parameter to fool gcc from optimizing */
 	func();
-
-	/* update the records */
-	ret = ftrace_force_update();
-	if (ret) {
-		printk(KERN_CONT ".. ftraced failed .. ");
-		return ret;
-	}
 
 	/*
 	 * Some archs *cough*PowerPC*cough* add charachters to the
···
 	/* make sure msleep has been recorded */
 	msleep(1);
 
-	/* force the recorded functions to be traced */
-	ret = ftrace_force_update();
-	if (ret) {
-		printk(KERN_CONT ".. ftraced failed .. ");
-		return ret;
-	}
-
 	/* start the tracing */
 	ftrace_enabled = 1;
 	tracer_enabled = 1;
···
 
 	return ret;
 }
-#endif /* CONFIG_FTRACE */
+#endif /* CONFIG_FUNCTION_TRACER */
 
 #ifdef CONFIG_IRQSOFF_TRACER
 int

kernel/trace/trace_stack.c

···
 	if (this_size <= max_stack_size)
 		return;
 
+	/* we do not handle interrupt stacks yet */
+	if (!object_is_on_stack(&this_size))
+		return;
+
 	raw_local_irq_save(flags);
 	__raw_spin_lock(&max_stack_lock);
 

kernel/tracepoint.c

···
 
 	old = entry->funcs;
 
+	if (!old)
+		return NULL;
+
 	debug_print_probes(entry);
 	/* (N -> M), (N > 1, M >= 0) probes */
 	for (nr_probes = 0; old[nr_probes]; nr_probes++) {
···
 	if (entry->rcu_pending)
 		rcu_barrier_sched();
 	old = tracepoint_entry_remove_probe(entry, probe);
+	if (!old) {
+		printk(KERN_WARNING "Warning: Trying to unregister a probe"
+				    "that doesn't exist\n");
+		goto end;
+	}
 	mutex_unlock(&tracepoints_mutex);
 	tracepoint_update_probes();		/* may update entry */
 	mutex_lock(&tracepoints_mutex);

lib/Makefile

···
 # Makefile for some libs needed in the kernel.
 #
 
-ifdef CONFIG_FTRACE
+ifdef CONFIG_FUNCTION_TRACER
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
 endif

scripts/Makefile.build

···
 	fi;
 endif
 
+ifdef CONFIG_64BIT
+arch_bits = 64
+else
+arch_bits = 32
+endif
+
 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl \
-	"$(ARCH)" "$(OBJDUMP)" "$(OBJCOPY)" "$(CC)" "$(LD)" "$(NM)" "$(RM)" \
-	"$(MV)" "$(@)";
+	"$(ARCH)" "$(arch_bits)" "$(OBJDUMP)" "$(OBJCOPY)" "$(CC)" "$(LD)" \
+	"$(NM)" "$(RM)" "$(MV)" "$(@)";
 endif
 
 define rule_cc_o_c

scripts/bootgraph.pl

···
 # 	dmesg | perl scripts/bootgraph.pl > output.svg
 #
 
-my %start, %end;
+use strict;
+
+my %start;
+my %end;
 my $done = 0;
 my $maxtime = 0;
 my $firsttime = 100;
···
 my $stylecounter = 0;
 my %rows;
 my $rowscount = 1;
-while (($key,$value) = each %start) {
+my @initcalls = sort { $start{$a} <=> $start{$b} } keys(%start);
+my $key;
+foreach $key (@initcalls) {
 	my $duration = $end{$key} - $start{$key};
 
 	if ($duration >= $threshold) {
-		my $s, $s2, $e, $y;
-		$pid = $pids{$key};
+		my ($s, $s2, $e, $w, $y, $y2, $style);
+		my $pid = $pids{$key};
 
 		if (!defined($rows{$pid})) {
 			$rows{$pid} = $rowscount;
 			$rowscount = $rowscount + 1;
 		}
-		$s = ($value - $firsttime) * $mult;
+		$s = ($start{$key} - $firsttime) * $mult;
 		$s2 = $s + 6;
 		$e = ($end{$key} - $firsttime) * $mult;
 		$w = $e - $s;
···
 my $time = $firsttime;
 my $step = ($maxtime - $firsttime) / 15;
 while ($time < $maxtime) {
-	my $s2 = ($time - $firsttime) * $mult;
+	my $s3 = ($time - $firsttime) * $mult;
 	my $tm = int($time * 100) / 100.0;
-	print "<text transform=\"translate($s2,89) rotate(90)\">$tm</text>\n";
+	print "<text transform=\"translate($s3,89) rotate(90)\">$tm</text>\n";
 	$time = $time + $step;
 }
 

scripts/recordmcount.pl

···
 	exit(1);
 }
 
-my ($arch, $objdump, $objcopy, $cc, $ld, $nm, $rm, $mv, $inputfile) = @ARGV;
+my ($arch, $bits, $objdump, $objcopy, $cc,
+    $ld, $nm, $rm, $mv, $inputfile) = @ARGV;
+
+# Acceptable sections to record.
+my %text_sections = (
+     ".text" => 1,
+);
 
 $objdump = "objdump" if ((length $objdump) == 0);
 $objcopy = "objcopy" if ((length $objcopy) == 0);
···
 			#    (return offset and func name)
 my $mcount_regex;	# Find the call site to mcount (return offset)
 
+if ($arch eq "x86") {
+    if ($bits == 64) {
+	$arch = "x86_64";
+    } else {
+	$arch = "i386";
+    }
+}
+
 if ($arch eq "x86_64") {
-    $section_regex = "Disassembly of section";
+    $section_regex = "Disassembly of section\\s+(\\S+):";
     $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:";
     $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount([+-]0x[0-9a-zA-Z]+)?\$";
     $type = ".quad";
···
     $cc .= " -m64";
 
 } elsif ($arch eq "i386") {
-    $section_regex = "Disassembly of section";
+    $section_regex = "Disassembly of section\\s+(\\S+):";
     $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:";
     $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount\$";
     $type = ".long";
···
 while (<IN>) {
     # is it a section?
     if (/$section_regex/) {
-	$read_function = 1;
+
+	# Only record text sections that we know are safe
+	if (defined($text_sections{$1})) {
+	    $read_function = 1;
+	} else {
+	    $read_function = 0;
+	}
 	# print out any recorded offsets
 	update_funcs() if ($text_found);