Commit 281b3714 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

Merge branch 'tip/tracing/core' of... 

Merge branch 'tip/tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/core
parents 64b9fb57 7b60997f

arch/x86/kernel/ftrace.c

+26 −0
Original line number Diff line number Diff line
@@ -30,14 +30,32 @@ 


#ifdef CONFIG_DYNAMIC_FTRACE



/*

 * modifying_code is set to notify NMIs that they need to use

 * memory barriers when entering or exiting. But we don't want

 * to burden NMIs with unnecessary memory barriers when code

 * modification is not being done (which is most of the time).

 *

 * A mutex is already held when ftrace_arch_code_modify_prepare

 * and post_process are called. No locks need to be taken here.

 *

 * Stop machine will make sure currently running NMIs are done

 * and new NMIs will see the updated variable before we need

 * to worry about NMIs doing memory barriers.

 */

static int modifying_code __read_mostly;

static DEFINE_PER_CPU(int, save_modifying_code);



int ftrace_arch_code_modify_prepare(void)

{

	set_kernel_text_rw();

	modifying_code = 1;

	return 0;

}



int ftrace_arch_code_modify_post_process(void)

{

	modifying_code = 0;

	set_kernel_text_ro();

	return 0;

}
@@ -149,6 +167,11 @@ static void ftrace_mod_code(void) 


void ftrace_nmi_enter(void)

{

	__get_cpu_var(save_modifying_code) = modifying_code;



	if (!__get_cpu_var(save_modifying_code))

		return;



	if (atomic_inc_return(&nmi_running) & MOD_CODE_WRITE_FLAG) {

		smp_rmb();

		ftrace_mod_code();
@@ -160,6 +183,9 @@ void ftrace_nmi_enter(void) 


void ftrace_nmi_exit(void)

{

	if (!__get_cpu_var(save_modifying_code))

		return;



	/* Finish all executions before clearing nmi_running */

	smp_mb();

	atomic_dec(&nmi_running);

include/linux/syscalls.h

+4 −2
Original line number Diff line number Diff line
@@ -132,7 +132,8 @@ struct perf_event_attr; 


#define SYSCALL_TRACE_ENTER_EVENT(sname)				\

	static const struct syscall_metadata __syscall_meta_##sname;	\

	static struct ftrace_event_call event_enter_##sname;		\

	static struct ftrace_event_call					\

	__attribute__((__aligned__(4))) event_enter_##sname;		\

	static struct trace_event enter_syscall_print_##sname = {	\

		.trace                  = print_syscall_enter,		\

	};								\
@@ -153,7 +154,8 @@ struct perf_event_attr; 


#define SYSCALL_TRACE_EXIT_EVENT(sname)					\

	static const struct syscall_metadata __syscall_meta_##sname;	\

	static struct ftrace_event_call event_exit_##sname;		\

	static struct ftrace_event_call					\

	__attribute__((__aligned__(4))) event_exit_##sname;		\

	static struct trace_event exit_syscall_print_##sname = {	\

		.trace                  = print_syscall_exit,		\

	};								\

include/trace/ftrace.h

+2 −1
Original line number Diff line number Diff line
@@ -65,7 +65,8 @@ 
	};

#undef DEFINE_EVENT

#define DEFINE_EVENT(template, name, proto, args)	\

	static struct ftrace_event_call event_##name

	static struct ftrace_event_call			\

	__attribute__((__aligned__(4))) event_##name



#undef DEFINE_EVENT_PRINT

#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\

kernel/trace/Kconfig

+0 −9
Original line number Diff line number Diff line
@@ -328,15 +328,6 @@ config BRANCH_TRACER 


	  Say N if unsure.



config POWER_TRACER

	bool "Trace power consumption behavior"

	depends on X86

	select GENERIC_TRACER

	help

	  This tracer helps developers to analyze and optimize the kernel's

	  power management decisions, specifically the C-state and P-state

	  behavior.



config KSYM_TRACER

	bool "Trace read and write access on kernel memory locations"

	depends on HAVE_HW_BREAKPOINT

kernel/trace/trace.h

+2 −1
Original line number Diff line number Diff line
@@ -792,7 +792,8 @@ extern const char *__stop___trace_bprintk_fmt[]; 


#undef FTRACE_ENTRY

#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)		\

	extern struct ftrace_event_call event_##call;

	extern struct ftrace_event_call					\

	__attribute__((__aligned__(4))) event_##call;

#undef FTRACE_ENTRY_DUP

#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)		\

	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))