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perf record: Allow to specify max stack depth of fp callchain

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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>
This commit is contained in:
Namhyung Kim 2022-06-15 09:32:21 -07:00 committed by Arnaldo Carvalho de Melo
parent 3ae03f2650
commit 7cb2a53f7f
2 changed files with 17 additions and 6 deletions
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5
tools/perf/Documentation/perf-record.txt
View File

@ -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.

18
tools/perf/util/callchain.c
View File

@ -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 */