Lines Matching refs:to
126 Adds a very slight overhead to tracing when enabled.
135 of the kernel can use them to generate or add hooks to them.
139 # This allows those options to appear when no other tracer is selected. But the
141 # GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
160 # Minimum requirements an architecture has to meet for us to
161 # be able to offer generic tracing facilities:
183 Enable developer to setup ftrace subsystem via supplemental
197 Enable the kernel to trace every kernel function. This is done
198 by using a compiler feature to insert a small, 5-byte No-Operation
213 Enable the kernel to trace a function at both its return
215 Its first purpose is to trace the duration of functions and
226 This option will modify all the calls to function tracing
267 The fprobe is similar to kprobes, but probes only for kernel function
279 in debugfs called function_profile_enabled which defaults to zero.
373 to be scheduled in, starting from the point it has woken up.
376 bool "Tracer to detect hardware latencies (like SMIs)"
381 depending on what the cpumask file is set to, which each thread
391 hwlat_detector/width - time in usecs for how long to spin for
398 continue to operate.
403 but when it is running, it can cause the system to be
417 System Noise (osnoise) refers to the interference experienced by an
418 application due to activities inside the operating system. In the
420 can cause noise to the system. Moreover, hardware-related jobs can
432 hardware noise counter increases, pointing to a hardware-related
438 In addition to the tracer, a set of tracepoints were added to
451 The timerlat tracer aims to help the preemptive kernel developers
452 to find sources of wakeup latencies of real-time threads.
455 The tracer thread sets a periodic timer to wakeup itself, and goes
456 to sleep waiting for the timer to fire. At the wakeup, the thread
459 to expire.
465 ACTIVATION ID field serves to relate the irq execution to its
469 events can be used to trace the source of interference from NMI,
471 stacktrace at the IRQ context, which helps to identify the code
485 If you are not helping to develop drivers, say N.
492 This tracer hooks to various trace points in the kernel,
493 allowing the user to pick and choose which trace point they
494 want to trace. It also includes the sched_switch tracer plugin.
502 Basic tracer to catch the syscall entry and exit events.
508 Allow tracing users to take snapshot of the current buffer using the
515 bool "Allow snapshot to swap per CPU"
528 When this is enabled, this adds a little more overhead to the
529 trace recording, as it needs to add some checks to synchronize
532 or irq latency tracers are enabled, as those need to swap as well
544 into the C conditionals to test which path a branch takes.
553 Either of the above profilers adds a bit of overhead to the system.
560 Only enable it if you want to analyse the branching behavior.
573 on if you need to profile the system's use of these macros.
589 is to be analyzed in much detail.
609 events into a running trace buffer to see when and where the
624 Say Y here if you want to be able to trace the block layer actions
625 on a given queue. Tracing allows you to see any traffic happening
648 This allows the user to add tracing events (similar to tracepoints)
656 If you want to use perf tools, this option is strongly recommended.
664 This is only for the developers who want to debug ftrace itself
668 functions are protected from kprobe-events to prevent an infinite
669 recursion or any unexpected execution path which leads to a kernel
672 This option disables such protection and allows you to put kprobe
689 This allows the user to add tracing events on top of userspace
690 dynamic events (similar to tracepoints) on the fly via the trace
693 This option is required if you plan to use perf-probe subcommand
702 This allows the user to attach BPF programs to kprobe, uprobe, and
712 bool "Enable BPF programs to override a kprobed function"
717 Allows BPF to override the execution of a probed function and
755 separated out as a stand-alone facility in order to allow it
756 to be shared between multiple tracers. It isn't meant to be
767 used to combine data from other trace events or in fact any
781 depends on BROKEN || COMPILE_TEST # API needs to be straighten out
785 events are generated by writing to a tracefs file. User
802 to be aggregated into hash tables and dumped to stdout by
818 Allow user-space to inject a specific trace event into the ring
828 goes into an infinite loop (calling cond_resched() to let other tasks
830 it took to write to the tracepoint and the next iteration that
831 data will be passed to the tracepoint itself. That is, the tracepoint
832 will report the time it took to do the previous tracepoint.
833 The string written to the tracepoint is a static string of 128 bytes
834 to keep the time the same. The initial string is simply a write of
836 write which is not added to the rest of the calculations.
857 This option creates a test to stress the ring buffer and benchmark it.
875 that use this string to parse the raw data as user space does not know
876 how to convert the string to its value.
879 to convert an enum/sizeof into its value. If this macro is used, then
880 the print fmt strings will be converted to their values.
883 used to show what enums/sizeof the kernel tried to convert.
890 Normally, the mapping of the strings to values will be freed after
901 All callbacks that attach to the function tracing have some sort
907 This will add more overhead to cases that have recursion.
912 int "Max number of recursed functions to record"
918 the functions that caused a recursion to happen.
934 This will add more overhead to cases that have recursion.
957 a series of tests are made to verify that the tracer is
980 TBD - enable a way to actually call the syscalls as we test their
988 Sorting of the mcount_loc sections that is used to find the
989 where the ftrace knows where to patch functions for tracing
1004 into the ring buffer. Another thread is created to send IPIs
1005 to each of the threads, where the IPI handler will also write
1006 to the ring buffer, to test/stress the nesting ability.
1025 buffer to make sure that all the time deltas for the
1029 is also made when traversing sub buffers to make sure
1031 add up to be greater than the current time stamp.
1033 NOTE: This adds significant overhead to recording of events,
1034 and should only be used to test the logic of the ring buffer.
1045 as it will write garbage to IO memory starting at a given address.
1046 However, it should be safe to use on e.g. unused portion of VRAM.
1051 tristate "Test module to create a preempt / IRQ disable delay thread to test latency tracers"
1054 Select this option to build a test module that can help test latency
1063 What's more, if you want to attach the test on the cpu which the latency
1073 This option creates a test module to check the base
1086 This option creates a test module to check the base
1106 - Provides educational information to support the details
1111 related to the histogram definitions themselves and doesn't