diff options
| author |   Namhyung Kim <namhyung@kernel.org> | 2022-06-15 09:32:21 -0700 |
|---|---|---|
| committer |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2022-07-12 09:56:05 -0300 |
| commit | 7cb2a53f7f413734734bac214c4855e9863b9853 (patch) | |
| tree | b7ed211604d0a98cfcfb3c24089e205024cb5694 /tools | |
| parent | perf lock: Handle lock contention tracepoints (diff) | |
| download | linux-dev-7cb2a53f7f413734734bac214c4855e9863b9853.tar.xz linux-dev-7cb2a53f7f413734734bac214c4855e9863b9853.zip | |
perf record: Allow to specify max stack depth of fp callchain
Currently it has no interface to specify the max stack depth for perf
record. Extend the command line parameter to accept a number after
'fp' to specify the depth like '--call-graph fp,32'.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220615163222.1275500-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/Documentation/perf-record.txt | 5 | ||||
| -rw-r--r-- | tools/perf/util/callchain.c | 18 |
2 files changed, 17 insertions, 6 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index 6bd6d07021ba..099817ef5150 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -275,6 +275,11 @@ OPTIONS User can change the size by passing the size after comma like "--call-graph dwarf,4096". + When "fp" recording is used, perf tries to save stack enties + up to the number specified in sysctl.kernel.perf_event_max_stack + by default. User can change the number by passing it after comma + like "--call-graph fp,32". + -q:: --quiet:: Don't print any message, useful for scripting. diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c index 5c27a4b2e7a7..7e663673f79f 100644 --- a/tools/perf/util/callchain.c +++ b/tools/perf/util/callchain.c @@ -31,6 +31,7 @@ #include "callchain.h" #include "branch.h" #include "symbol.h" +#include "util.h" #include "../perf.h" #define CALLCHAIN_PARAM_DEFAULT \ @@ -266,12 +267,17 @@ int parse_callchain_record(const char *arg, struct callchain_param *param) do { /* Framepointer style */ if (!strncmp(name, "fp", sizeof("fp"))) { - if (!strtok_r(NULL, ",", &saveptr)) { - param->record_mode = CALLCHAIN_FP; - ret = 0; - } else - pr_err("callchain: No more arguments " - "needed for --call-graph fp\n"); + ret = 0; + param->record_mode = CALLCHAIN_FP; + + tok = strtok_r(NULL, ",", &saveptr); + if (tok) { + unsigned long size; + + size = strtoul(tok, &name, 0); + if (size < (unsigned) sysctl__max_stack()) + param->max_stack = size; + } break; /* Dwarf style */ |