diff --git a/[refs] b/[refs]
index f960d4afbfd8..6dace9883359 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 468a15bb4cc61694495cc5ed7ffca29e87c79b69
+refs/heads/master: bf53de907dfdaac178c92d774aae7370d7b97d20
diff --git a/trunk/arch/x86/include/asm/ds.h b/trunk/arch/x86/include/asm/ds.h
index ee0ea3a96c11..a8f672ba100c 100644
--- a/trunk/arch/x86/include/asm/ds.h
+++ b/trunk/arch/x86/include/asm/ds.h
@@ -252,12 +252,21 @@ extern void __cpuinit ds_init_intel(struct cpuinfo_x86 *);
  */
 extern void ds_switch_to(struct task_struct *prev, struct task_struct *next);
 
+/*
+ * Task clone/init and cleanup work
+ */
+extern void ds_copy_thread(struct task_struct *tsk, struct task_struct *father);
+extern void ds_exit_thread(struct task_struct *tsk);
+
 #else /* CONFIG_X86_DS */
 
 struct cpuinfo_x86;
 static inline void __cpuinit ds_init_intel(struct cpuinfo_x86 *ignored) {}
 static inline void ds_switch_to(struct task_struct *prev,
 				struct task_struct *next) {}
+static inline void ds_copy_thread(struct task_struct *tsk,
+				  struct task_struct *father) {}
+static inline void ds_exit_thread(struct task_struct *tsk) {}
 
 #endif /* CONFIG_X86_DS */
 #endif /* _ASM_X86_DS_H */
diff --git a/trunk/arch/x86/include/asm/msr.h b/trunk/arch/x86/include/asm/msr.h
index b8a1799ea871..c2a812ebde89 100644
--- a/trunk/arch/x86/include/asm/msr.h
+++ b/trunk/arch/x86/include/asm/msr.h
@@ -85,8 +85,7 @@ static inline void native_write_msr(unsigned int msr,
 	asm volatile("wrmsr" : : "c" (msr), "a"(low), "d" (high) : "memory");
 }
 
-/* Can be uninlined because referenced by paravirt */
-notrace static inline int native_write_msr_safe(unsigned int msr,
+static inline int native_write_msr_safe(unsigned int msr,
 					unsigned low, unsigned high)
 {
 	int err;
diff --git a/trunk/arch/x86/include/asm/ptrace.h b/trunk/arch/x86/include/asm/ptrace.h
index fbf744215911..6d34d954c228 100644
--- a/trunk/arch/x86/include/asm/ptrace.h
+++ b/trunk/arch/x86/include/asm/ptrace.h
@@ -235,6 +235,13 @@ extern int do_get_thread_area(struct task_struct *p, int idx,
 extern int do_set_thread_area(struct task_struct *p, int idx,
 			      struct user_desc __user *info, int can_allocate);
 
+extern void x86_ptrace_untrace(struct task_struct *);
+extern void x86_ptrace_fork(struct task_struct *child,
+			    unsigned long clone_flags);
+
+#define arch_ptrace_untrace(tsk) x86_ptrace_untrace(tsk)
+#define arch_ptrace_fork(child, flags) x86_ptrace_fork(child, flags)
+
 #endif /* __KERNEL__ */
 
 #endif /* !__ASSEMBLY__ */
diff --git a/trunk/arch/x86/kernel/cpu/Makefile b/trunk/arch/x86/kernel/cpu/Makefile
index 4ae495a313f3..82ec6075c057 100644
--- a/trunk/arch/x86/kernel/cpu/Makefile
+++ b/trunk/arch/x86/kernel/cpu/Makefile
@@ -2,11 +2,6 @@
 # Makefile for x86-compatible CPU details and quirks
 #
 
-# Don't trace early stages of a secondary CPU boot
-ifdef CONFIG_FUNCTION_TRACER
-CFLAGS_REMOVE_common.o = -pg
-endif
-
 obj-y			:= intel_cacheinfo.o addon_cpuid_features.o
 obj-y			+= proc.o capflags.o powerflags.o common.o
 
diff --git a/trunk/arch/x86/kernel/ds.c b/trunk/arch/x86/kernel/ds.c
index 98d271e60e08..da91701a2348 100644
--- a/trunk/arch/x86/kernel/ds.c
+++ b/trunk/arch/x86/kernel/ds.c
@@ -1017,3 +1017,14 @@ void ds_switch_to(struct task_struct *prev, struct task_struct *next)
 
 	update_debugctlmsr(next->thread.debugctlmsr);
 }
+
+void ds_copy_thread(struct task_struct *tsk, struct task_struct *father)
+{
+	clear_tsk_thread_flag(tsk, TIF_DS_AREA_MSR);
+	tsk->thread.ds_ctx = NULL;
+}
+
+void ds_exit_thread(struct task_struct *tsk)
+{
+	WARN_ON(tsk->thread.ds_ctx);
+}
diff --git a/trunk/arch/x86/kernel/process_32.c b/trunk/arch/x86/kernel/process_32.c
index 605eff9a8ac0..3ba155d24884 100644
--- a/trunk/arch/x86/kernel/process_32.c
+++ b/trunk/arch/x86/kernel/process_32.c
@@ -60,6 +60,7 @@
 #include <asm/idle.h>
 #include <asm/syscalls.h>
 #include <asm/smp.h>
+#include <asm/ds.h>
 
 asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
 
@@ -251,17 +252,8 @@ void exit_thread(void)
 		tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;
 		put_cpu();
 	}
-#ifdef CONFIG_X86_DS
-	/* Free any BTS tracers that have not been properly released. */
-	if (unlikely(current->bts)) {
-		ds_release_bts(current->bts);
-		current->bts = NULL;
-
-		kfree(current->bts_buffer);
-		current->bts_buffer = NULL;
-		current->bts_size = 0;
-	}
-#endif /* CONFIG_X86_DS */
+
+	ds_exit_thread(current);
 }
 
 void flush_thread(void)
@@ -343,6 +335,12 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 		kfree(p->thread.io_bitmap_ptr);
 		p->thread.io_bitmap_max = 0;
 	}
+
+	ds_copy_thread(p, current);
+
+	clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
+	p->thread.debugctlmsr = 0;
+
 	return err;
 }
 
diff --git a/trunk/arch/x86/kernel/process_64.c b/trunk/arch/x86/kernel/process_64.c
index 1cfd2a4bf853..416fb9282f4f 100644
--- a/trunk/arch/x86/kernel/process_64.c
+++ b/trunk/arch/x86/kernel/process_64.c
@@ -53,6 +53,7 @@
 #include <asm/ia32.h>
 #include <asm/idle.h>
 #include <asm/syscalls.h>
+#include <asm/ds.h>
 
 asmlinkage extern void ret_from_fork(void);
 
@@ -236,17 +237,8 @@ void exit_thread(void)
 		t->io_bitmap_max = 0;
 		put_cpu();
 	}
-#ifdef CONFIG_X86_DS
-	/* Free any BTS tracers that have not been properly released. */
-	if (unlikely(current->bts)) {
-		ds_release_bts(current->bts);
-		current->bts = NULL;
-
-		kfree(current->bts_buffer);
-		current->bts_buffer = NULL;
-		current->bts_size = 0;
-	}
-#endif /* CONFIG_X86_DS */
+
+	ds_exit_thread(current);
 }
 
 void flush_thread(void)
@@ -376,6 +368,12 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 		if (err)
 			goto out;
 	}
+
+	ds_copy_thread(p, me);
+
+	clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
+	p->thread.debugctlmsr = 0;
+
 	err = 0;
 out:
 	if (err && p->thread.io_bitmap_ptr) {
diff --git a/trunk/arch/x86/kernel/ptrace.c b/trunk/arch/x86/kernel/ptrace.c
index 45e9855da2d2..6ad2bb607650 100644
--- a/trunk/arch/x86/kernel/ptrace.c
+++ b/trunk/arch/x86/kernel/ptrace.c
@@ -769,8 +769,47 @@ static int ptrace_bts_size(struct task_struct *child)
 
 	return (trace->ds.top - trace->ds.begin) / trace->ds.size;
 }
+
+static void ptrace_bts_fork(struct task_struct *tsk)
+{
+	tsk->bts = NULL;
+	tsk->bts_buffer = NULL;
+	tsk->bts_size = 0;
+	tsk->thread.bts_ovfl_signal = 0;
+}
+
+static void ptrace_bts_untrace(struct task_struct *child)
+{
+	if (unlikely(child->bts)) {
+		ds_release_bts(child->bts);
+		child->bts = NULL;
+
+		kfree(child->bts_buffer);
+		child->bts_buffer = NULL;
+		child->bts_size = 0;
+	}
+}
+
+static void ptrace_bts_detach(struct task_struct *child)
+{
+	ptrace_bts_untrace(child);
+}
+#else
+static inline void ptrace_bts_fork(struct task_struct *tsk) {}
+static inline void ptrace_bts_detach(struct task_struct *child) {}
+static inline void ptrace_bts_untrace(struct task_struct *child) {}
 #endif /* CONFIG_X86_PTRACE_BTS */
 
+void x86_ptrace_fork(struct task_struct *child, unsigned long clone_flags)
+{
+	ptrace_bts_fork(child);
+}
+
+void x86_ptrace_untrace(struct task_struct *child)
+{
+	ptrace_bts_untrace(child);
+}
+
 /*
  * Called by kernel/ptrace.c when detaching..
  *
@@ -782,16 +821,7 @@ void ptrace_disable(struct task_struct *child)
 #ifdef TIF_SYSCALL_EMU
 	clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 #endif
-#ifdef CONFIG_X86_PTRACE_BTS
-	if (child->bts) {
-		ds_release_bts(child->bts);
-		child->bts = NULL;
-
-		kfree(child->bts_buffer);
-		child->bts_buffer = NULL;
-		child->bts_size = 0;
-	}
-#endif /* CONFIG_X86_PTRACE_BTS */
+	ptrace_bts_detach(child);
 }
 
 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
diff --git a/trunk/arch/x86/kernel/smpboot.c b/trunk/arch/x86/kernel/smpboot.c
index f6174d229024..f71f96fc9e62 100644
--- a/trunk/arch/x86/kernel/smpboot.c
+++ b/trunk/arch/x86/kernel/smpboot.c
@@ -287,7 +287,7 @@ static int __cpuinitdata unsafe_smp;
 /*
  * Activate a secondary processor.
  */
-notrace static void __cpuinit start_secondary(void *unused)
+static void __cpuinit start_secondary(void *unused)
 {
 	/*
 	 * Don't put *anything* before cpu_init(), SMP booting is too
diff --git a/trunk/include/linux/ftrace.h b/trunk/include/linux/ftrace.h
index 677432b9cb7e..04b52e6ebc66 100644
--- a/trunk/include/linux/ftrace.h
+++ b/trunk/include/linux/ftrace.h
@@ -303,7 +303,7 @@ extern void ftrace_dump(void);
 static inline void
 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
 static inline int
-ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
+ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 0)));
 
 static inline void tracing_start(void) { }
 static inline void tracing_stop(void) { }
diff --git a/trunk/include/linux/ptrace.h b/trunk/include/linux/ptrace.h
index 22641d5d45df..98b93ca4db06 100644
--- a/trunk/include/linux/ptrace.h
+++ b/trunk/include/linux/ptrace.h
@@ -94,6 +94,7 @@ extern void ptrace_notify(int exit_code);
 extern void __ptrace_link(struct task_struct *child,
 			  struct task_struct *new_parent);
 extern void __ptrace_unlink(struct task_struct *child);
+extern void ptrace_fork(struct task_struct *task, unsigned long clone_flags);
 #define PTRACE_MODE_READ   1
 #define PTRACE_MODE_ATTACH 2
 /* Returns 0 on success, -errno on denial. */
@@ -313,6 +314,27 @@ static inline void user_enable_block_step(struct task_struct *task)
 #define arch_ptrace_stop(code, info)		do { } while (0)
 #endif
 
+#ifndef arch_ptrace_untrace
+/*
+ * Do machine-specific work before untracing child.
+ *
+ * This is called for a normal detach as well as from ptrace_exit()
+ * when the tracing task dies.
+ *
+ * Called with write_lock(&tasklist_lock) held.
+ */
+#define arch_ptrace_untrace(task)		do { } while (0)
+#endif
+
+#ifndef arch_ptrace_fork
+/*
+ * Do machine-specific work to initialize a new task.
+ *
+ * This is called from copy_process().
+ */
+#define arch_ptrace_fork(child, clone_flags)	do { } while (0)
+#endif
+
 extern int task_current_syscall(struct task_struct *target, long *callno,
 				unsigned long args[6], unsigned int maxargs,
 				unsigned long *sp, unsigned long *pc);
diff --git a/trunk/include/trace/sched.h b/trunk/include/trace/sched.h
index 0d81098ee9fc..bc4c9eadc6ba 100644
--- a/trunk/include/trace/sched.h
+++ b/trunk/include/trace/sched.h
@@ -17,8 +17,8 @@ DECLARE_TRACE(sched_wait_task,
 		TPARGS(rq, p));
 
 DECLARE_TRACE(sched_wakeup,
-	TPPROTO(struct rq *rq, struct task_struct *p, int success),
-		TPARGS(rq, p, success));
+	TPPROTO(struct rq *rq, struct task_struct *p),
+		TPARGS(rq, p));
 
 DECLARE_TRACE(sched_wakeup_new,
 	TPPROTO(struct rq *rq, struct task_struct *p, int success),
diff --git a/trunk/kernel/fork.c b/trunk/kernel/fork.c
index 7b93da72d4a2..65ce60adc8e8 100644
--- a/trunk/kernel/fork.c
+++ b/trunk/kernel/fork.c
@@ -1096,6 +1096,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #ifdef CONFIG_DEBUG_MUTEXES
 	p->blocked_on = NULL; /* not blocked yet */
 #endif
+	if (unlikely(ptrace_reparented(current)))
+		ptrace_fork(p, clone_flags);
 
 	/* Perform scheduler related setup. Assign this task to a CPU. */
 	sched_fork(p, clone_flags);
diff --git a/trunk/kernel/ptrace.c b/trunk/kernel/ptrace.c
index 4c8bcd7dd8e0..100a71cfdaba 100644
--- a/trunk/kernel/ptrace.c
+++ b/trunk/kernel/ptrace.c
@@ -25,6 +25,17 @@
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
 
+
+/*
+ * Initialize a new task whose father had been ptraced.
+ *
+ * Called from copy_process().
+ */
+void ptrace_fork(struct task_struct *child, unsigned long clone_flags)
+{
+	arch_ptrace_fork(child, clone_flags);
+}
+
 /*
  * ptrace a task: make the debugger its new parent and
  * move it to the ptrace list.
@@ -72,6 +83,7 @@ void __ptrace_unlink(struct task_struct *child)
 	child->parent = child->real_parent;
 	list_del_init(&child->ptrace_entry);
 
+	arch_ptrace_untrace(child);
 	if (task_is_traced(child))
 		ptrace_untrace(child);
 }
diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
index dcb39bc88f6c..ceda5799466e 100644
--- a/trunk/kernel/sched.c
+++ b/trunk/kernel/sched.c
@@ -2324,7 +2324,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
 	success = 1;
 
 out_running:
-	trace_sched_wakeup(rq, p, success);
+	trace_sched_wakeup(rq, p);
 	check_preempt_curr(rq, p, sync);
 
 	p->state = TASK_RUNNING;
diff --git a/trunk/kernel/trace/trace.c b/trunk/kernel/trace/trace.c
index 79db26e8216e..0eb6d48347f7 100644
--- a/trunk/kernel/trace/trace.c
+++ b/trunk/kernel/trace/trace.c
@@ -679,16 +679,6 @@ void tracing_reset(struct trace_array *tr, int cpu)
 	ftrace_enable_cpu();
 }
 
-void tracing_reset_online_cpus(struct trace_array *tr)
-{
-	int cpu;
-
-	tr->time_start = ftrace_now(tr->cpu);
-
-	for_each_online_cpu(cpu)
-		tracing_reset(tr, cpu);
-}
-
 #define SAVED_CMDLINES 128
 static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
 static unsigned map_cmdline_to_pid[SAVED_CMDLINES];
diff --git a/trunk/kernel/trace/trace.h b/trunk/kernel/trace/trace.h
index cc7a4f864036..fc75dce7a664 100644
--- a/trunk/kernel/trace/trace.h
+++ b/trunk/kernel/trace/trace.h
@@ -374,7 +374,6 @@ struct trace_iterator {
 int tracing_is_enabled(void);
 void trace_wake_up(void);
 void tracing_reset(struct trace_array *tr, int cpu);
-void tracing_reset_online_cpus(struct trace_array *tr);
 int tracing_open_generic(struct inode *inode, struct file *filp);
 struct dentry *tracing_init_dentry(void);
 void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
diff --git a/trunk/kernel/trace/trace_boot.c b/trunk/kernel/trace/trace_boot.c
index 3ccebde28482..a4fa2c57e34e 100644
--- a/trunk/kernel/trace/trace_boot.c
+++ b/trunk/kernel/trace/trace_boot.c
@@ -37,6 +37,16 @@ void disable_boot_trace(void)
 		tracing_stop_sched_switch_record();
 }
 
+static void reset_boot_trace(struct trace_array *tr)
+{
+	int cpu;
+
+	tr->time_start = ftrace_now(tr->cpu);
+
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
+}
+
 static int boot_trace_init(struct trace_array *tr)
 {
 	int cpu;
@@ -120,7 +130,7 @@ struct tracer boot_tracer __read_mostly =
 {
 	.name		= "initcall",
 	.init		= boot_trace_init,
-	.reset		= tracing_reset_online_cpus,
+	.reset		= reset_boot_trace,
 	.print_line	= initcall_print_line,
 };
 
diff --git a/trunk/kernel/trace/trace_functions.c b/trunk/kernel/trace/trace_functions.c
index 9236d7e25a16..e74f6d0a3216 100644
--- a/trunk/kernel/trace/trace_functions.c
+++ b/trunk/kernel/trace/trace_functions.c
@@ -16,10 +16,20 @@
 
 #include "trace.h"
 
+static void function_reset(struct trace_array *tr)
+{
+	int cpu;
+
+	tr->time_start = ftrace_now(tr->cpu);
+
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
+}
+
 static void start_function_trace(struct trace_array *tr)
 {
 	tr->cpu = get_cpu();
-	tracing_reset_online_cpus(tr);
+	function_reset(tr);
 	put_cpu();
 
 	tracing_start_cmdline_record();
@@ -45,7 +55,7 @@ static void function_trace_reset(struct trace_array *tr)
 
 static void function_trace_start(struct trace_array *tr)
 {
-	tracing_reset_online_cpus(tr);
+	function_reset(tr);
 }
 
 static struct tracer function_trace __read_mostly =
diff --git a/trunk/kernel/trace/trace_hw_branches.c b/trunk/kernel/trace/trace_hw_branches.c
index b6a3e20a49a9..ee29e012aa97 100644
--- a/trunk/kernel/trace/trace_hw_branches.c
+++ b/trunk/kernel/trace/trace_hw_branches.c
@@ -25,6 +25,16 @@ static DEFINE_PER_CPU(unsigned char[SIZEOF_BTS], buffer);
 #define this_buffer per_cpu(buffer, smp_processor_id())
 
 
+static void bts_trace_reset(struct trace_array *tr)
+{
+	int cpu;
+
+	tr->time_start = ftrace_now(tr->cpu);
+
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
+}
+
 static void bts_trace_start_cpu(void *arg)
 {
 	if (this_tracer)
@@ -44,7 +54,7 @@ static void bts_trace_start(struct trace_array *tr)
 {
 	int cpu;
 
-	tracing_reset_online_cpus(tr);
+	bts_trace_reset(tr);
 
 	for_each_cpu_mask(cpu, cpu_possible_map)
 		smp_call_function_single(cpu, bts_trace_start_cpu, NULL, 1);
@@ -68,7 +78,7 @@ static void bts_trace_stop(struct trace_array *tr)
 
 static int bts_trace_init(struct trace_array *tr)
 {
-	tracing_reset_online_cpus(tr);
+	bts_trace_reset(tr);
 	bts_trace_start(tr);
 
 	return 0;
diff --git a/trunk/kernel/trace/trace_mmiotrace.c b/trunk/kernel/trace/trace_mmiotrace.c
index fffcb069f1dc..2fb6da6523b3 100644
--- a/trunk/kernel/trace/trace_mmiotrace.c
+++ b/trunk/kernel/trace/trace_mmiotrace.c
@@ -22,10 +22,14 @@ static unsigned long prev_overruns;
 
 static void mmio_reset_data(struct trace_array *tr)
 {
+	int cpu;
+
 	overrun_detected = false;
 	prev_overruns = 0;
+	tr->time_start = ftrace_now(tr->cpu);
 
-	tracing_reset_online_cpus(tr);
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
 }
 
 static int mmio_trace_init(struct trace_array *tr)
diff --git a/trunk/kernel/trace/trace_sched_switch.c b/trunk/kernel/trace/trace_sched_switch.c
index df175cb4564f..781d72ef873c 100644
--- a/trunk/kernel/trace/trace_sched_switch.c
+++ b/trunk/kernel/trace/trace_sched_switch.c
@@ -49,7 +49,7 @@ probe_sched_switch(struct rq *__rq, struct task_struct *prev,
 }
 
 static void
-probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success)
+probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee)
 {
 	struct trace_array_cpu *data;
 	unsigned long flags;
@@ -72,6 +72,16 @@ probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success)
 	local_irq_restore(flags);
 }
 
+static void sched_switch_reset(struct trace_array *tr)
+{
+	int cpu;
+
+	tr->time_start = ftrace_now(tr->cpu);
+
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
+}
+
 static int tracing_sched_register(void)
 {
 	int ret;
@@ -187,7 +197,7 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr)
 
 static void start_sched_trace(struct trace_array *tr)
 {
-	tracing_reset_online_cpus(tr);
+	sched_switch_reset(tr);
 	tracing_start_sched_switch_record();
 }
 
@@ -211,7 +221,7 @@ static void sched_switch_trace_reset(struct trace_array *tr)
 
 static void sched_switch_trace_start(struct trace_array *tr)
 {
-	tracing_reset_online_cpus(tr);
+	sched_switch_reset(tr);
 	tracing_start_sched_switch();
 }
 
diff --git a/trunk/kernel/trace/trace_sched_wakeup.c b/trunk/kernel/trace/trace_sched_wakeup.c
index 43586b689e31..0067b49746c1 100644
--- a/trunk/kernel/trace/trace_sched_wakeup.c
+++ b/trunk/kernel/trace/trace_sched_wakeup.c
@@ -211,7 +211,7 @@ static void wakeup_reset(struct trace_array *tr)
 }
 
 static void
-probe_wakeup(struct rq *rq, struct task_struct *p, int success)
+probe_wakeup(struct rq *rq, struct task_struct *p)
 {
 	int cpu = smp_processor_id();
 	unsigned long flags;
diff --git a/trunk/kernel/trace/trace_sysprof.c b/trunk/kernel/trace/trace_sysprof.c
index 01becf1f19ff..54960edb96d0 100644
--- a/trunk/kernel/trace/trace_sysprof.c
+++ b/trunk/kernel/trace/trace_sysprof.c
@@ -234,10 +234,20 @@ static void stop_stack_timers(void)
 		stop_stack_timer(cpu);
 }
 
+static void stack_reset(struct trace_array *tr)
+{
+	int cpu;
+
+	tr->time_start = ftrace_now(tr->cpu);
+
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
+}
+
 static void start_stack_trace(struct trace_array *tr)
 {
 	mutex_lock(&sample_timer_lock);
-	tracing_reset_online_cpus(tr);
+	stack_reset(tr);
 	start_stack_timers();
 	tracer_enabled = 1;
 	mutex_unlock(&sample_timer_lock);