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e5f2024cb9
Like trace subcommand, it should be able to pass some options to control
the tracing behavior for the function graph tracer.
But some options are limited in order to maintain the internal behavior.
For example, it can limit the function call depth like below:
# perf ftrace profile --graph-opts depth=5 -- myprog
Committer testing:
root@number:~# perf ftrace profile --graph-opts thresh=1000 -- sleep 1
# Total (us) Avg (us) Max (us) Count Function
1001419.301 500709.650 1000032.000 2 x64_sys_call
1000032.000 1000032.000 1000032.000 1 __x64_sys_clock_nanosleep
1000032.000 1000032.000 1000032.000 1 common_nsleep
1000031.000 1000031.000 1000031.000 1 do_nanosleep
1000031.000 1000031.000 1000031.000 1 hrtimer_nanosleep
1000024.000 1000024.000 1000024.000 1 schedule
1387.208 1387.208 1387.208 1 __x64_sys_execve
1386.691 1386.691 1386.691 1 do_execveat_common.isra.0
1334.170 1334.170 1334.170 1 bprm_execve
1258.413 1258.413 1258.413 1 load_elf_binary
1123.068 1123.068 1123.068 1 begin_new_exec
1113.550 1113.550 1113.550 1 mmput
1109.237 1109.237 1109.237 1 exit_mmap
root@number:~# perf ftrace profile --graph-opts thresh=1200 -- sleep 1
# Total (us) Avg (us) Max (us) Count Function
1001448.204 500724.102 1000018.000 2 x64_sys_call
1000017.000 1000017.000 1000017.000 1 __x64_sys_clock_nanosleep
1000017.000 1000017.000 1000017.000 1 common_nsleep
1000017.000 1000017.000 1000017.000 1 hrtimer_nanosleep
1000016.000 1000016.000 1000016.000 1 do_nanosleep
1000012.000 1000012.000 1000012.000 1 schedule
1430.112 1430.112 1430.112 1 __x64_sys_execve
1429.581 1429.581 1429.581 1 do_execveat_common.isra.0
1376.289 1376.289 1376.289 1 bprm_execve
1301.743 1301.743 1301.743 1 load_elf_binary
root@number:~#
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250107224352.1128669-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.