Lines Matching +full:entry +full:- +full:latency
1 # SPDX-License-Identifier: GPL-2.0-only
21 API, which will be used by other function-entry hooking
27 See Documentation/trace/ftrace-design.rst
32 See Documentation/trace/ftrace-design.rst
45 See Documentation/trace/ftrace-design.rst
80 See Documentation/trace/ftrace-design.rst
85 See Documentation/trace/ftrace-design.rst
90 Arch supports the gcc options -pg with -mfentry
95 Arch supports the gcc options -pg with -mrecord-mcount and -nop-mcount
100 Arch supports objtool --mcount
105 Arch supports the objtool options --mcount with --mnop.
203 bool "Boot-time Tracing support"
222 by using a compiler feature to insert a small, 5-byte No-Operation
227 small and not measurable even in micro-benchmarks (at least on
238 and its entry.
253 enable it via the trace option funcgraph-retval.
264 enable it via the trace option funcgraph-retaddr.
274 enabled via the trace option func-args (for the function tracer) and
275 funcgraph-args (for the function graph tracer)
285 replace them with a No-Op instruction) on boot up. During
359 stack-trace saved. If this is configured with DYNAMIC_FTRACE
378 bool "Interrupts-off Latency Tracer"
388 This option measures the time spent in irqs-off critical
392 disabled by default and can be runtime (re-)started
398 enabled. This option and the preempt-off timing option can be
402 bool "Preemption-off Latency Tracer"
412 This option measures the time spent in preemption-off critical
416 disabled by default and can be runtime (re-)started
422 enabled. This option and the irqs-off timing option can be
426 bool "Scheduling Latency Tracer"
432 This tracer tracks the latency of the highest priority task
451 hwlat_detector/width - time in usecs for how long to spin for
452 hwlat_detector/window - time in usecs between the start of each
457 for "window - width" microseconds, where the system can
468 file. Every time a latency is greater than tracing_thresh, it will
476 In the context of high-performance computing (HPC), the Operating
480 can cause noise to the system. Moreover, hardware-related jobs can
486 note of the entry and exit point of any source of interferences,
487 increasing a per-cpu interference counter. It saves an interference
490 observes these interferences' entry events. When a noise happens
492 hardware noise counter increases, pointing to a hardware-related
512 to find sources of wakeup latencies of real-time threads.
514 The tracer creates a per-cpu kernel thread with real-time priority.
517 then computes a wakeup latency value as the difference between
522 timer latency observed at the hardirq context before the
523 activation of the thread. The second is the timer latency observed
542 default and can be enabled at run-time.
562 Basic tracer to catch the syscall entry and exit events.
592 or irq latency tracers are enabled, as those need to swap as well
609 The "all branch" profiler will profile every if-statement in the
702 bool "Enable fprobe-based dynamic events"
708 This allows user to add tracing events on the function entry and
710 and the kprobe events on function entry and exit will be
722 kernel function entry or a tracepoint.
728 bool "Enable kprobes-based dynamic events"
741 This option is also required by perf-probe subcommand of perf tools.
754 functions are protected from kprobe-events to prevent an infinite
765 bool "Enable uprobes-based dynamic events"
779 This option is required if you plan to use perf-probe subcommand
817 depends on $(cc-option,-mrecord-mcount)
840 tracing_map is a special-purpose lock-free map for tracing,
841 separated out as a stand-alone facility in order to allow it
852 Synthetic events are user-defined trace events that can be
856 by way of an in-kernel API.
868 User trace events are user-defined trace events that
894 Inter-event tracing of quantities such as latencies is also
904 Allow user-space to inject a specific trace event into the ring
1079 TBD - enable a way to actually call the syscalls as we test their
1090 is not done correctly, it will cause non-deterministic failures.
1150 tristate "Test module to create a preempt / IRQ disable delay thread to test latency tracers"
1153 Select this option to build a test module that can help test latency
1159 irq-disabled critical sections for 500us:
1162 What's more, if you want to attach the test on the cpu which the latency
1169 tristate "Test module for in-kernel synthetic event generation"
1173 functionality of in-kernel synthetic event definition and
1182 tristate "Test module for in-kernel kprobe event generation"
1186 functionality of in-kernel kprobe event definition.
1203 - Helps developers verify that nothing is broken.
1205 - Provides educational information to support the details
1207 Documentation/trace/histogram-design.rst.