perf evsel: Emit warning about kernel not supporting the data page size sample_type bit

Before we had this unhelpful message:

  $ perf record --data-page-size sleep 1
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles:u).
  /bin/dmesg | grep -i perf may provide additional information.
  $

Add support to the perf_missing_features variable to remember what
caused evsel__open() to fail and then use that information in
evsel__open_strerror().

  $ perf record --data-page-size sleep 1
  Error:
  Asking for the data page size isn't supported by this kernel.
  $

Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Stephane Eranian <eranian@google.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lore.kernel.org/lkml/20201207170759.GB129853@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2020-12-07 14:04:05 -03:00
parent 542b88fd12
commit 456ef4c11c
2 changed files with 9 additions and 1 deletions

View file

@ -1873,7 +1873,12 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
* Must probe features in the order they were added to the
* perf_event_attr interface.
*/
if (!perf_missing_features.cgroup && evsel->core.attr.cgroup) {
if (!perf_missing_features.data_page_size &&
(evsel->core.attr.sample_type & PERF_SAMPLE_DATA_PAGE_SIZE)) {
perf_missing_features.data_page_size = true;
pr_debug2_peo("Kernel has no PERF_SAMPLE_DATA_PAGE_SIZE support, bailing out\n");
goto out_close;
} else if (!perf_missing_features.cgroup && evsel->core.attr.cgroup) {
perf_missing_features.cgroup = true;
pr_debug2_peo("Kernel has no cgroup sampling support, bailing out\n");
goto out_close;
@ -2673,6 +2678,8 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target,
"We found oprofile daemon running, please stop it and try again.");
break;
case EINVAL:
if (evsel->core.attr.sample_type & PERF_SAMPLE_DATA_PAGE_SIZE && perf_missing_features.data_page_size)
return scnprintf(msg, size, "Asking for the data page size isn't supported by this kernel.");
if (evsel->core.attr.write_backward && perf_missing_features.write_backward)
return scnprintf(msg, size, "Reading from overwrite event is not supported by this kernel.");
if (perf_missing_features.clockid)

View file

@ -144,6 +144,7 @@ struct perf_missing_features {
bool aux_output;
bool branch_hw_idx;
bool cgroup;
bool data_page_size;
};
extern struct perf_missing_features perf_missing_features;