[PATCH] perf report: Create option to disable raw event ordering

From: Jin Yao
Date: Fri Feb 19 2021 - 02:06:45 EST


Warning "dso not found" is reported when using "perf report -D".

66702781413407 0x32c0 [0x30]: PERF_RECORD_SAMPLE(IP, 0x2): 28177/28177: 0x55e493e00563 period: 106578 addr: 0
... thread: perf:28177
...... dso: <not found>

66702727832429 0x9dd8 [0x38]: PERF_RECORD_COMM exec: triad_loop:28177/28177

The PERF_RECORD_SAMPLE event (timestamp: 66702781413407) should be after the
PERF_RECORD_COMM event (timestamp: 66702727832429), but it's early processed.

So for most of cases, it makes sense to keep the event ordered even for dump
mode. But it would be also useful to disable ordered_events for reporting raw
dump to see events as they are stored in the perf.data file.

So now, set ordered_events by default to true and add a new option
'disable-order' to disable it. For example,

perf report -D --disable-order

Fixes: 977f739b7126b ("perf report: Disable ordered_events for raw dump")
Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
tools/perf/Documentation/perf-report.txt | 3 +++
tools/perf/builtin-report.c | 5 ++++-
2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index f546b5e9db05..87112e8d904e 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -224,6 +224,9 @@ OPTIONS
--dump-raw-trace::
Dump raw trace in ASCII.

+--disable-order::
+ Disable raw trace ordering.
+
-g::
--call-graph=<print_type,threshold[,print_limit],order,sort_key[,branch],value>::
Display call chains using type, min percent threshold, print limit,
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 2a845d6cac09..0d65c98794a8 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -84,6 +84,7 @@ struct report {
bool nonany_branch_mode;
bool group_set;
bool stitch_lbr;
+ bool disable_order;
int max_stack;
struct perf_read_values show_threads_values;
struct annotation_options annotation_opts;
@@ -1296,6 +1297,8 @@ int cmd_report(int argc, const char **argv)
OPTS_EVSWITCH(&report.evswitch),
OPT_BOOLEAN(0, "total-cycles", &report.total_cycles_mode,
"Sort all blocks by 'Sampled Cycles%'"),
+ OPT_BOOLEAN(0, "disable-order", &report.disable_order,
+ "Disable raw trace ordering"),
OPT_END()
};
struct perf_data data = {
@@ -1329,7 +1332,7 @@ int cmd_report(int argc, const char **argv)
if (report.mmaps_mode)
report.tasks_mode = true;

- if (dump_trace)
+ if (dump_trace && report.disable_order)
report.tool.ordered_events = false;

if (quiet)
--
2.17.1