Lines Matching refs:tracing
27 is really a frame work 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
83 (cd /sys/kernel/tracing) and will only concentrate on the files within that
85 "/sys/kernel/tracing" path name.
112 writing to the ring buffer, the tracing overhead may
117 set this file to "0". User space can re-enable tracing by
121 set this file to zero and stop tracing. Which can also
127 readable format (described below). Note, tracing is temporarily
133 file is meant to be streamed with live tracing.
143 disable tracing while being read.
202 If a process is performing tracing, and the ring buffer should be
206 Having a process that is tracing also open this file, when the process
210 It may also stop tracing if disable_on_free option is set.
222 function profiler (mcount). This lets tracing be configured
276 tracing when the function is hit until it exits the function.
277 This makes it possible to ignore tracing functions that are called
336 A directory that holds different tracing stats.
419 Usual clocks for tracing::
472 tracing in the suspend path, some side effects are possible
516 that are written into /sys/kernel/tracing/events/ftrace/print/trigger
560 A list of events that can be enabled in tracing.
573 Usual timestamp modes for tracing:
751 This tracer can be configured when tracing likely/unlikely
759 tracers from tracing simply echo "nop" into
855 This shows that the current tracer is "irqsoff" tracing the time
1089 impact of tracing. See "saved_cmdlines".
1105 When the free_buffer is closed, tracing will
1135 The latency tracers will enable function tracing
1150 use function graph tracing instead of function tracing.
1157 Enable branch tracing with the tracer. This enables branch
1395 enabling function tracing, we incur an added overhead. This
1621 function tracing, we do not know if interrupts were enabled
1729 One common case that people are interested in tracing is the
1731 Now for non Real-Time tasks, this can be arbitrary. But tracing
1734 Without function tracing::
1766 to avoid tracing the normal circumstances. Here we see that
1793 tracing non-RT tasks that are unpredictable will overwrite the
1837 is before the actual "switch", we stop the tracing when the recorded task
1964 This isn't that big of a trace, even with function tracing enabled,
1971 Latency tracing and events
1973 As function tracing can induce a much larger latency, but without
2142 the tracing could have overwritten the data that you wanted to
2144 tracing directly from a program. This allows you to stop the
2145 tracing at the point that you hit the part that you are
2146 interested in. To disable the tracing directly from a C program,
2162 Single thread tracing
2243 strcat(tracefs, "/tracing/");
2292 echo nop > $tracefs/tracing/current_tracer
2293 echo 0 > $tracefs/tracing/tracing_on
2294 echo $$ > $tracefs/tracing/set_ftrace_pid
2295 echo function > $tracefs/tracing/current_tracer
2296 echo 1 > $tracefs/tracing/tracing_on
2364 function calls while cpu tracing switch.
2527 following "dynamic ftrace" section such as tracing only specific
2534 virtually no overhead when function tracing is disabled. The way
2568 When tracing is enabled, the process of modifying the function
2593 tracing of specified functions. They are:
2785 We can see that there's no more lock or preempt tracing.
2853 function tracer. By default it is enabled (when function tracing is
2854 enabled in the kernel). If it is disabled, all function tracing is
2856 also for any other uses (perf, kprobes, stack tracing, profiling, etc).
2896 Mod command supports module globbing. Disable tracing for all
2901 Disable tracing for all modules, but still trace kernel::
2914 These commands turn tracing on and off when the specified
2916 tracing system is turned on and off. If unspecified, there is
2917 no limit. For example, to disable tracing when a schedule bug
2922 To always disable tracing when __schedule_bug is hit::
2955 function tracing callbacks are very sensitive, when these commands
2994 the effect on the tracing is different. Every read from
3101 in time without stopping tracing. Ftrace swaps the current
3102 buffer with a spare buffer, and tracing continues in the new
3105 The following tracefs files in "tracing" are related to this
3115 System"). Both reads snapshot and tracing are executable
3181 In the tracefs tracing directory is a directory called "instances".
3194 As you can see, the new directory looks similar to the tracing directory
3200 same name in the tracing directory except the buffer that is used
3292 the function tracing. The foo instance displays wakeups and task
3320 CONFIG_STACK_TRACER enables the ftrace stack tracing functionality.