Lines Matching full:tracing
27 is really a framework of several assorted tracing utilities.
28 There's latency tracing to examine what occurs between interrupts
32 One of the most common uses of ftrace is the event tracing.
53 option will do) the directory /sys/kernel/tracing will be created. To mount
56 tracefs /sys/kernel/tracing tracefs defaults 0 0
60 mount -t tracefs nodev /sys/kernel/tracing
65 ln -s /sys/kernel/tracing /tracing
69 Before 4.1, all ftrace tracing control files were within the debugfs
70 file system, which is typically located at /sys/kernel/debug/tracing.
74 /sys/kernel/debug/tracing
86 (cd /sys/kernel/tracing) and will only concentrate on the files within that
88 "/sys/kernel/tracing" path name.
116 writing to the ring buffer, the tracing overhead may
121 set this file to "0". User space can re-enable tracing by
125 set this file to zero and stop tracing. Which can also
133 Note, this file is not a consumer. If tracing is off
135 the same output each time it is read. When tracing is on,
142 file is meant to be streamed with live tracing.
211 If a process is performing tracing, and the ring buffer should be
215 Having a process that is tracing also open this file, when the process
219 It may also stop tracing if disable_on_free option is set.
231 function profiler (mcount). This lets tracing be configured
246 and requires a check of all functions registered to tracing, instead
318 tracing when the function is hit until it exits the function.
319 This makes it possible to ignore tracing functions that are called
378 A directory that holds different tracing stats.
461 Usual clocks for tracing::
514 tracing in the suspend path, some side effects are possible
561 that are written into /sys/kernel/tracing/events/ftrace/print/trigger
605 A list of events that can be enabled in tracing.
618 Usual timestamp modes for tracing:
796 This tracer can be configured when tracing likely/unlikely
804 tracers from tracing simply echo "nop" into
814 available via the tracing/error_log file. For the commands that
815 support it, reading the tracing/error_log file after an error will
817 information is available. The tracing/error_log file is a circular
824 # echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
827 # cat /sys/kernel/debug/tracing/error_log
837 # echo > /sys/kernel/debug/tracing/error_log
931 This shows that the current tracer is "irqsoff" tracing the time
1163 When the file is closed, tracing will be enabled again.
1171 impact of tracing. See "saved_cmdlines".
1187 When the free_buffer is closed, tracing will
1219 The latency tracers will enable function tracing
1236 use function graph tracing instead of function tracing.
1243 Enable branch tracing with the tracer. This enables branch
1481 enabling function tracing, we incur an added overhead. This
1759 function tracing, we do not know if interrupts were enabled
1867 One common case that people are interested in tracing is the
1869 Now for non Real-Time tasks, this can be arbitrary. But tracing
1872 Without function tracing::
1904 to avoid tracing the normal circumstances. Here we see that
1931 tracing non-RT tasks that are unpredictable will overwrite the
1975 is before the actual "switch", we stop the tracing when the recorded task
2102 This isn't that big of a trace, even with function tracing enabled,
2109 Latency tracing and events
2111 As function tracing can induce a much larger latency, but without
2292 the tracing could have overwritten the data that you wanted to
2294 tracing directly from a program. This allows you to stop the
2295 tracing at the point that you hit the part that you are
2296 interested in. To disable the tracing directly from a C program,
2312 Single thread tracing
2393 strcat(tracefs, "/tracing/");
2442 echo nop > $tracefs/tracing/current_tracer
2443 echo 0 > $tracefs/tracing/tracing_on
2444 echo $$ > $tracefs/tracing/set_ftrace_pid
2445 echo function > $tracefs/tracing/current_tracer
2446 echo 1 > $tracefs/tracing/tracing_on
2514 function calls while cpu tracing switch.
2677 following "dynamic ftrace" section such as tracing only specific
2684 virtually no overhead when function tracing is disabled. The way
2718 When tracing is enabled, the process of modifying the function
2743 tracing of specified functions. They are:
2935 We can see that there's no more lock or preempt tracing.
3035 function tracer. By default it is enabled (when function tracing is
3036 enabled in the kernel). If it is disabled, all function tracing is
3038 also for any other uses (perf, kprobes, stack tracing, profiling, etc). It
3080 Mod command supports module globbing. Disable tracing for all
3085 Disable tracing for all modules, but still trace kernel::
3098 These commands turn tracing on and off when the specified
3100 tracing system is turned on and off. If unspecified, there is
3101 no limit. For example, to disable tracing when a schedule bug
3106 To always disable tracing when __schedule_bug is hit::
3139 function tracing callbacks are very sensitive, when these commands
3181 the effect on the tracing is different. Every read from
3220 the trace file for reading, it will actually disable tracing and
3291 in time without stopping tracing. Ftrace swaps the current
3292 buffer with a spare buffer, and tracing continues in the new
3295 The following tracefs files in "tracing" are related to this
3305 System"). Both reads snapshot and tracing are executable
3371 In the tracefs tracing directory is a directory called "instances".
3384 As you can see, the new directory looks similar to the tracing directory
3390 same name in the tracing directory except the buffer that is used
3482 the function tracing. The foo instance displays wakeups and task
3510 CONFIG_STACK_TRACER enables the ftrace stack tracing functionality.