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| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-04-27 16:16:24 +0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-04-27 16:29:07 +0300 |
| commit | 4cb93446c587d56e2a54f4f83113daba2c0b6dee (patch) | |
| tree | a251b1d510831dc071eadbbbe3e38a85fe643365 /tools/perf/builtin-top.c | |
| parent | c5dfd78eb79851e278b7973031b9ca363da87a7e (diff) | |
| download | linux-4cb93446c587d56e2a54f4f83113daba2c0b6dee.tar.xz | |
perf tools: Set the maximum allowed stack from /proc/sys/kernel/perf_event_max_stack
There is an upper limit to what tooling considers a valid callchain,
and it was tied to the hardcoded value in the kernel,
PERF_MAX_STACK_DEPTH (127), now that this can be tuned via a sysctl,
make it read it and use that as the upper limit, falling back to
PERF_MAX_STACK_DEPTH for kernels where this sysctl isn't present.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-yjqsd30nnkogvj5oyx9ghir9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-top.c')
| -rw-r--r-- | tools/perf/builtin-top.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index c130a11d3a0d..da18517b1d40 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -1103,7 +1103,7 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused) }, .proc_map_timeout = 500, }, - .max_stack = PERF_MAX_STACK_DEPTH, + .max_stack = sysctl_perf_event_max_stack, .sym_pcnt_filter = 5, }; struct record_opts *opts = &top.record_opts; @@ -1171,7 +1171,7 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused) "Accumulate callchains of children and show total overhead as well"), OPT_INTEGER(0, "max-stack", &top.max_stack, "Set the maximum stack depth when parsing the callchain. " - "Default: " __stringify(PERF_MAX_STACK_DEPTH)), + "Default: kernel.perf_event_max_stack or " __stringify(PERF_MAX_STACK_DEPTH)), OPT_CALLBACK(0, "ignore-callees", NULL, "regex", "ignore callees of these functions in call graphs", report_parse_ignore_callees_opt), |