Lines Matching +full:mmu +full:- +full:500 +full:s
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
37 See Documentation/trace/ftrace-design.rst
63 See Documentation/trace/ftrace-design.rst
68 See Documentation/trace/ftrace-design.rst
73 Arch supports the gcc options -pg with -mfentry
78 Arch supports the gcc options -pg with -mrecord-mcount and -nop-mcount
83 Arch supports objtool --mcount
179 bool "Boot-time Tracing support"
198 by using a compiler feature to insert a small, 5-byte No-Operation
201 tracing is enabled by the administrator. If it's runtime disabled
203 small and not measurable even in micro-benchmarks (at least on
228 replace them with a No-Op instruction) on boot up. During
299 stack-trace saved. If this is configured with DYNAMIC_FTRACE
318 bool "Interrupts-off Latency Tracer"
328 This option measures the time spent in irqs-off critical
332 disabled by default and can be runtime (re-)started
338 enabled. This option and the preempt-off timing option can be
342 bool "Preemption-off Latency Tracer"
352 This option measures the time spent in preemption-off critical
356 disabled by default and can be runtime (re-)started
362 enabled. This option and the irqs-off timing option can be
390 hwlat_detector/width - time in usecs for how long to spin for
391 hwlat_detector/window - time in usecs between the start of each
396 for "window - width" microseconds, where the system can
414 In the context of high-performance computing (HPC), the Operating
418 can cause noise to the system. Moreover, hardware-related jobs can
425 increasing a per-cpu interference counter. It saves an interference
430 hardware noise counter increases, pointing to a hardware-related
450 to find sources of wakeup latencies of real-time threads.
452 The tracer creates a per-cpu kernel thread with real-time priority.
480 default and can be enabled at run-time.
547 The "all branch" profiler will profile every if-statement in the
571 on if you need to profile the system's use of these macros.
640 bool "Enable kprobes-based dynamic events"
653 This option is also required by perf-probe subcommand of perf tools.
666 functions are protected from kprobe-events to prevent an infinite
677 bool "Enable uprobes-based dynamic events"
679 depends on MMU
691 This option is required if you plan to use perf-probe subcommand
729 depends on $(cc-option,-mrecord-mcount)
752 tracing_map is a special-purpose lock-free map for tracing,
753 separated out as a stand-alone facility in order to allow it
764 Synthetic events are user-defined trace events that can be
768 by way of an in-kernel API.
781 User trace events are user-defined trace events that
786 an associated byte being non-zero.
806 Inter-event tracing of quantities such as latencies is also
816 Allow user-space to inject a specific trace event into the ring
836 As it is a tight loop, it benchmarks as hot cache. That's fine because
876 To fix this, there's a special macro in the kernel that can be used
978 TBD - enable a way to actually call the syscalls as we test their
989 is not done correctly, it will cause non-deterministic failures.
1058 irq-disabled critical sections for 500us:
1059 modprobe preemptirq_delay_test test_mode=irq delay=500 burst_size=3
1061 What's more, if you want to attach the test on the cpu which the latency
1068 tristate "Test module for in-kernel synthetic event generation"
1072 functionality of in-kernel synthetic event definition and
1081 tristate "Test module for in-kernel kprobe event generation"
1085 functionality of in-kernel kprobe event definition.
1102 - Helps developers verify that nothing is broken.
1104 - Provides educational information to support the details
1106 Documentation/trace/histogram-design.rst.