Merge branches 'tracing/blktrace', 'tracing/ftrace',... (c7cc7730) · Commits · e / devices / android_kernel_fairphone_FP5

Documentation/ftrace.txt

+79 −0

Original line number	Diff line number	Diff line
		@@ -127,6 +127,8 @@ of ftrace. Here is a list of some of the key files:
		be traced. If a function exists in both set_ftrace_filter
		and set_ftrace_notrace, the function will _not_ be traced.

		set_ftrace_pid: Have the function tracer only trace a single thread.

		available_filter_functions: This lists the functions that ftrace
		has processed and can trace. These are the function
		names that you can pass to "set_ftrace_filter" or
		@@ -1073,6 +1075,83 @@ For simple one time traces, the above is sufficent. For anything else,
		a search through /proc/mounts may be needed to find where the debugfs
		file-system is mounted.


		Single thread tracing
		---------------------

		By writing into /debug/tracing/set_ftrace_pid you can trace a
		single thread. For example:

		# cat /debug/tracing/set_ftrace_pid
		no pid
		# echo 3111 > /debug/tracing/set_ftrace_pid
		# cat /debug/tracing/set_ftrace_pid
		3111
		# echo function > /debug/tracing/current_tracer
		# cat /debug/tracing/trace \| head
		# tracer: function
		#
		# TASK-PID CPU# TIMESTAMP FUNCTION
		# \| \| \| \| \|
		yum-updatesd-3111 [003] 1637.254676: finish_task_switch <-thread_return
		yum-updatesd-3111 [003] 1637.254681: hrtimer_cancel <-schedule_hrtimeout_range
		yum-updatesd-3111 [003] 1637.254682: hrtimer_try_to_cancel <-hrtimer_cancel
		yum-updatesd-3111 [003] 1637.254683: lock_hrtimer_base <-hrtimer_try_to_cancel
		yum-updatesd-3111 [003] 1637.254685: fget_light <-do_sys_poll
		yum-updatesd-3111 [003] 1637.254686: pipe_poll <-do_sys_poll
		# echo -1 > /debug/tracing/set_ftrace_pid
		# cat /debug/tracing/trace \|head
		# tracer: function
		#
		# TASK-PID CPU# TIMESTAMP FUNCTION
		# \| \| \| \| \|
		##### CPU 3 buffer started ####
		yum-updatesd-3111 [003] 1701.957688: free_poll_entry <-poll_freewait
		yum-updatesd-3111 [003] 1701.957689: remove_wait_queue <-free_poll_entry
		yum-updatesd-3111 [003] 1701.957691: fput <-free_poll_entry
		yum-updatesd-3111 [003] 1701.957692: audit_syscall_exit <-sysret_audit
		yum-updatesd-3111 [003] 1701.957693: path_put <-audit_syscall_exit

		If you want to trace a function when executing, you could use
		something like this simple program:

		#include <stdio.h>
		#include <stdlib.h>
		#include <sys/types.h>
		#include <sys/stat.h>
		#include <fcntl.h>
		#include <unistd.h>

		int main (int argc, char **argv)
		{
		if (argc < 1)
		exit(-1);

		if (fork() > 0) {
		int fd, ffd;
		char line[64];
		int s;

		ffd = open("/debug/tracing/current_tracer", O_WRONLY);
		if (ffd < 0)
		exit(-1);
		write(ffd, "nop", 3);

		fd = open("/debug/tracing/set_ftrace_pid", O_WRONLY);
		s = sprintf(line, "%d\n", getpid());
		write(fd, line, s);

		write(ffd, "function", 8);

		close(fd);
		close(ffd);

		execvp(argv[1], argv+1);
		}

		return 0;
		}

		dynamic ftrace
		--------------

arch/x86/Kconfig

+1 −1

Original line number	Diff line number	Diff line
		@@ -29,7 +29,7 @@ config X86
		select HAVE_FTRACE_MCOUNT_RECORD
		select HAVE_DYNAMIC_FTRACE
		select HAVE_FUNCTION_TRACER
		select HAVE_FUNCTION_RET_TRACER if X86_32
		select HAVE_FUNCTION_GRAPH_TRACER if X86_32
		select HAVE_FUNCTION_TRACE_MCOUNT_TEST
		select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) \|\| X86_64)
		select HAVE_ARCH_KGDB if !X86_VOYAGER

arch/x86/include/asm/ftrace.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -28,7 +28,7 @@ struct dyn_arch_ftrace {
		#endif /* __ASSEMBLY__ */
		#endif /* CONFIG_FUNCTION_TRACER */

		#ifdef CONFIG_FUNCTION_RET_TRACER
		#ifdef CONFIG_FUNCTION_GRAPH_TRACER

		#ifndef __ASSEMBLY__

		@@ -51,6 +51,6 @@ struct ftrace_ret_stack {
		extern void return_to_handler(void);

		#endif /* __ASSEMBLY__ */
		#endif /* CONFIG_FUNCTION_RET_TRACER */
		#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

		#endif /* _ASM_X86_FTRACE_H */

arch/x86/kernel/Makefile

+2 −2

Original line number	Diff line number	Diff line
		@@ -14,7 +14,7 @@ CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
		CFLAGS_REMOVE_ftrace.o = -pg
		endif

		ifdef CONFIG_FUNCTION_RET_TRACER
		ifdef CONFIG_FUNCTION_GRAPH_TRACER
		# Don't trace __switch_to() but let it for function tracer
		CFLAGS_REMOVE_process_32.o = -pg
		endif
		@@ -70,7 +70,7 @@ obj-$(CONFIG_X86_LOCAL_APIC) += apic.o nmi.o
		obj-$(CONFIG_X86_IO_APIC) += io_apic.o
		obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o
		obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
		obj-$(CONFIG_FUNCTION_RET_TRACER) += ftrace.o
		obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
		obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o
		obj-$(CONFIG_KEXEC) += relocate_kernel_$(BITS).o crash.o
		obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o

arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -33,6 +33,7 @@
		#include <linux/cpufreq.h>
		#include <linux/compiler.h>
		#include <linux/dmi.h>
		#include <linux/ftrace.h>

		#include <linux/acpi.h>
		#include <acpi/processor.h>
		@@ -391,6 +392,7 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
		unsigned int next_perf_state = 0; /* Index into perf table */
		unsigned int i;
		int result = 0;
		struct power_trace it;

		dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);

		@@ -427,6 +429,8 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
		}
		}

		trace_power_mark(&it, POWER_PSTATE, next_perf_state);

		switch (data->cpu_feature) {
		case SYSTEM_INTEL_MSR_CAPABLE:
		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;