redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

perf evsel: Provide meaningful warning when trying to use 'aux_output' on older kernels 

Just like we do with the 'write_backwards' feature:

Before:

  # perf record -e {intel_pt/branch=0/,cycles/aux-output/ppp} uname
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles/aux-output/ppp).
  /bin/dmesg | grep -i perf may provide additional information.

  #

After:

  # perf record -e {intel_pt/branch=0/,cycles/aux-output/ppp} uname
  Error:
  The 'aux_output' feature is not supported, update the kernel.
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-wgjsjroe1e150c0metgwmqwd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
alistair/sunxi64-5.4-dsi
Arnaldo Carvalho de Melo 2019-08-13 11:06:38 -03:00
parent 243384dd25
commit acb9f2d475
2 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
tools/perf/util/evsel.c
View File

@ -1738,7 +1738,8 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
int pid = -1, err;
enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
if (perf_missing_features.write_backward && evsel->core.attr.write_backward)
if ((perf_missing_features.write_backward && evsel->core.attr.write_backward) ||
(perf_missing_features.aux_output && evsel->core.attr.aux_output))
return -EINVAL;
if (cpus == NULL) {
@ -1912,7 +1913,11 @@ try_fallback:
* Must probe features in the order they were added to the
* perf_event_attr interface.
*/
if (!perf_missing_features.bpf_event && evsel->core.attr.bpf_event) {
if (!perf_missing_features.aux_output && evsel->core.attr.aux_output) {
perf_missing_features.aux_output = true;
pr_debug2("Kernel has no attr.aux_output support, bailing out\n");
goto out_close;
} else if (!perf_missing_features.bpf_event && evsel->core.attr.bpf_event) {
perf_missing_features.bpf_event = true;
pr_debug2("switching off bpf_event\n");
goto fallback_missing_features;
@ -2926,6 +2931,8 @@ int perf_evsel__open_strerror(struct evsel *evsel, struct target *target,
return scnprintf(msg, size, "clockid feature not supported.");
if (perf_missing_features.clockid_wrong)
return scnprintf(msg, size, "wrong clockid (%d).", clockid);
if (perf_missing_features.aux_output)
return scnprintf(msg, size, "The 'aux_output' feature is not supported, update the kernel.");
break;
default:
break;

1
tools/perf/util/evsel.h
View File

@ -184,6 +184,7 @@ struct perf_missing_features {
bool group_read;
bool ksymbol;
bool bpf_event;
bool aux_output;
};
extern struct perf_missing_features perf_missing_features;