linux/tools/perf/Documentation/perf.txt

96 lines
2.7 KiB
Plaintext
Raw Normal View History

perf(1)
=======
NAME
----
perf - Performance analysis tools for Linux
SYNOPSIS
--------
[verse]
'perf' [--version] [--help] [OPTIONS] COMMAND [ARGS]
OPTIONS
-------
-h::
--help::
Run perf help command.
-v::
--version::
Display perf version.
-vv::
Print the compiled-in status of libraries.
--exec-path::
Display or set exec path.
--html-path::
Display html documentation path.
-p::
--paginate::
Set up pager.
--no-pager::
Do not set pager.
--buildid-dir::
Setup buildid cache directory. It has higher priority
than buildid.dir config file option.
--list-cmds::
List the most commonly used perf commands.
--list-opts::
List available perf options.
--debugfs-dir::
Set debugfs directory or set environment variable PERF_DEBUGFS_DIR.
--debug::
Setup debug variable (see list below) in value
range (0, 10). Use like:
--debug verbose # sets verbose = 1
--debug verbose=2 # sets verbose = 2
List of debug variables allowed to set:
verbose - general debug messages
ordered-events - ordered events object debug messages
data-convert - data convert command debug messages
stderr - write debug output (option -v) to stderr
in browser mode
perf-event-open - Print perf_event_open() arguments and
return value
perf tools: Make it possible to see perf's kernel and module memory mappings Dump kmaps if using 'perf --debug kmaps' or verbose > 2 (e.g. -vvv) for tools 'perf script' and 'perf report' if there is no browser. Example: $ perf --debug kmaps script 2>&1 >/dev/null | grep kvm.intel build id event received for /lib/modules/6.7.2-local/kernel/arch/x86/kvm/kvm-intel.ko: 0691d75e10e72ebbbd45a44c59f6d00a5604badf [20] Map: 0-3a3 4f5d8 [kvm_intel].modinfo Map: 0-5240 5f280 [kvm_intel]__versions Map: 0-30 64 [kvm_intel].note.Linux Map: 0-14 644c0 [kvm_intel].orc_header Map: 0-5297 43680 [kvm_intel].rodata Map: 0-5bee 3b837 [kvm_intel].text.unlikely Map: 0-7e0 41430 [kvm_intel].noinstr.text Map: 0-2080 713c0 [kvm_intel].bss Map: 0-26 705c8 [kvm_intel].data..read_mostly Map: 0-5888 6a4c0 [kvm_intel].data Map: 0-22 70220 [kvm_intel].data.once Map: 0-40 705f0 [kvm_intel].data..percpu Map: 0-1685 41d20 [kvm_intel].init.text Map: 0-4b8 6fd60 [kvm_intel].init.data Map: 0-380 70248 [kvm_intel]__dyndbg Map: 0-8 70218 [kvm_intel].exit.data Map: 0-438 4f980 [kvm_intel]__param Map: 0-5f5 4ca0f [kvm_intel].rodata.str1.1 Map: 0-3657 493b8 [kvm_intel].rodata.str1.8 Map: 0-e0 70640 [kvm_intel].data..ro_after_init Map: 0-500 70ec0 [kvm_intel].gnu.linkonce.this_module Map: ffffffffc13a7000-ffffffffc1421000 a0 /lib/modules/6.7.2-local/kernel/arch/x86/kvm/kvm-intel.ko The example above shows how the module section mappings are all wrong except for the main .text mapping at 0xffffffffc13a7000. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Like Xu <like.xu.linux@gmail.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240208085326.13432-2-adrian.hunter@intel.com
2024-02-08 11:53:25 +03:00
kmaps - Print kernel and module maps (perf script
and perf report without browser)
perf tools: Add --debug-file option to redirect debug output Currently, debug messages is output to stderr, add --debug-file option to support redirection to a specified file. Some test scenarios: # perf --list-opts --help --version --exec-path --html-path --paginate --no-pager --debugfs-dir --buildid-dir --list-cmds --list-opts --debug --debug-file # perf --debug-file No path given for --debug-file. Usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS] # perf --debug-file /sys/perf.log record -v true Open debug file '/sys/perf.log' failed: Permission denied Usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS] # perf --debug-file /tmp/perf.log record -v true [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.013 MB perf.data (26 samples) ] # cat /tmp/perf.log DEBUGINFOD_URLS= Using CPUID GenuineIntel-6-3E-4 nr_cblocks: 0 affinity: SYS mmap flush: 1 comp level: 0 mmap size 528384B Control descriptor is not initialized mmap size 528384B Looking at the vmlinux_path (8 entries long) Using /proc/kcore for kernel data Using /proc/kallsyms for symbols symbol:unmap_start file:(null) line:0 offset:0 return:0 lazy:(null) symbol:unmap_complete file:(null) line:0 offset:0 return:0 lazy:(null) symbol:map_start file:(null) line:0 offset:0 return:0 lazy:(null) symbol:map_complete file:(null) line:0 offset:0 return:0 lazy:(null) symbol:reloc_start file:(null) line:0 offset:0 return:0 lazy:(null) symbol:reloc_complete file:(null) line:0 offset:0 return:0 lazy:(null) symbol:init_start file:(null) line:0 offset:0 return:0 lazy:(null) symbol:init_complete file:(null) line:0 offset:0 return:0 lazy:(null) symbol:lll_lock_wait_private file:(null) line:0 offset:0 return:0 lazy:(null) symbol:lll_lock_wait file:(null) line:0 offset:0 return:0 lazy:(null) symbol:setjmp file:(null) line:0 offset:0 return:0 lazy:(null) symbol:longjmp file:(null) line:0 offset:0 return:0 lazy:(null) symbol:longjmp_target file:(null) line:0 offset:0 return:0 lazy:(null) failed to write feature HYBRID_TOPOLOGY Signed-off-by: Yang Jihong <yangjihong1@huawei.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20231031105523.1472558-1-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-10-31 13:55:23 +03:00
--debug-file::
Write debug output to a specified file.
DESCRIPTION
-----------
Performance counters for Linux are a new kernel-based subsystem
that provide a framework for all things performance analysis. It
covers hardware level (CPU/PMU, Performance Monitoring Unit) features
and software features (software counters, tracepoints) as well.
SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-top[1],
linkperf:perf-record[1], linkperf:perf-report[1],
linkperf:perf-list[1]
linkperf:perf-annotate[1],linkperf:perf-archive[1],linkperf:perf-arm-spe[1],
linkperf:perf-bench[1], linkperf:perf-buildid-cache[1],
linkperf:perf-buildid-list[1], linkperf:perf-c2c[1],
linkperf:perf-config[1], linkperf:perf-data[1], linkperf:perf-diff[1],
linkperf:perf-evlist[1], linkperf:perf-ftrace[1],
linkperf:perf-help[1], linkperf:perf-inject[1],
linkperf:perf-intel-pt[1], linkperf:perf-iostat[1], linkperf:perf-kallsyms[1],
linkperf:perf-kmem[1], linkperf:perf-kvm[1], linkperf:perf-lock[1],
linkperf:perf-mem[1], linkperf:perf-probe[1], linkperf:perf-sched[1],
linkperf:perf-script[1], linkperf:perf-test[1],
linkperf:perf-trace[1], linkperf:perf-version[1]