[PATCH 5/5] perf callchains: Ask for PERF_RECORD_MMAP for data mmaps for DWARF unwinding

From: Arnaldo Carvalho de Melo
Date: Tue Jan 16 2018 - 09:25:20 EST


From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

When we use a global DWARF setting as in:

perf record --call-graph dwarf

According to 5c0cf22477ea ("perf record: Store data mmaps for dwarf unwind") we need
to set up some extra perf_event_attr bits.

But when we instead do a per event dwarf setting:

perf record -e cycles/call-graph=dwarf/

This was not being done, make them equivalent.

This didn't produce any output changes in my tests while fixing up loose
ends in the per-event settings, I found it just by comparing the
perf_event_attr fields trying to find an explanation for those problems.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Hendrick Brueckner <brueckner@xxxxxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Noel Grandin <noelgrandin@xxxxxxxxx>
Cc: Thomas Richter <tmricht@xxxxxxxxxxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-k26j3srv1pjbvwtak2c6yljc@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/evsel.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 8f971a2301d1..85eb84dfdf91 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -726,7 +726,7 @@ perf_evsel__reset_callgraph(struct perf_evsel *evsel,
}

static void apply_config_terms(struct perf_evsel *evsel,
- struct record_opts *opts)
+ struct record_opts *opts, bool track)
{
struct perf_evsel_config_term *term;
struct list_head *config_terms = &evsel->config_terms;
@@ -797,6 +797,8 @@ static void apply_config_terms(struct perf_evsel *evsel,

/* User explicitly set per-event callgraph, clear the old setting and reset. */
if ((callgraph_buf != NULL) || (dump_size > 0) || max_stack) {
+ bool sample_address = false;
+
if (max_stack) {
param.max_stack = max_stack;
if (callgraph_buf == NULL)
@@ -816,6 +818,8 @@ static void apply_config_terms(struct perf_evsel *evsel,
evsel->name);
return;
}
+ if (param.record_mode == CALLCHAIN_DWARF)
+ sample_address = true;
}
}
if (dump_size > 0) {
@@ -828,8 +832,14 @@ static void apply_config_terms(struct perf_evsel *evsel,
perf_evsel__reset_callgraph(evsel, &callchain_param);

/* set perf-event callgraph */
- if (param.enabled)
+ if (param.enabled) {
+ if (sample_address) {
+ perf_evsel__set_sample_bit(evsel, ADDR);
+ perf_evsel__set_sample_bit(evsel, DATA_SRC);
+ evsel->attr.mmap_data = track;
+ }
perf_evsel__config_callchain(evsel, opts, &param);
+ }
}
}

@@ -1060,7 +1070,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts,
* Apply event specific term settings,
* it overloads any global configuration.
*/
- apply_config_terms(evsel, opts);
+ apply_config_terms(evsel, opts, track);

evsel->ignore_missing_thread = opts->ignore_missing_thread;
}
--
2.14.3