diff options
author | Kim Phillips <kim.phillips@amd.com> | 2022-03-23 01:15:15 +0300 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2022-03-26 16:55:58 +0300 |
commit | ab0809af0bee88b689ba289ec8c40aa2be3a17ec (patch) | |
tree | a6eb8069a5afcb48f83d3bceb8fecfe3d1b9da48 /tools/perf/util | |
parent | b58230de3ccdc2f4566d576b34b5f1feceea2e73 (diff) | |
download | linux-ab0809af0bee88b689ba289ec8c40aa2be3a17ec.tar.xz |
perf evsel: Improve AMD IBS (Instruction-Based Sampling) error handling messages
Improve the error message returned on failed perf_event_open() on AMD
systems when using IBS (Instruction-Based Sampling).
Output of executing 'perf record -e ibs_op// true' as a non root user
BEFORE this patch (perf will add the 'u' modifier at the end to exclude
kernel/hypervisor sampling):
The sys_perf_event_open() syscall returned with 22 (Invalid argument)for event (ibs_op//u).
/bin/dmesg | grep -i perf may provide additional information.
Output after:
AMD IBS can't exclude kernel events. Try running at a higher privilege level.
Output of executing 'sudo perf record -e ibs_op// true' BEFORE this patch:
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (ibs_op//).
/bin/dmesg | grep -i perf may provide additional information.
Output after:
Error:
Invalid event (ibs_op//) in per-thread mode, enable system wide with '-a'.
Folowing the suggestion:
$ sudo perf record -a -e ibs_op// true
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.664 MB perf.data (194 samples) ]
$
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: João Martins <joao.m.martins@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20220322221517.2510440-12-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util')
-rw-r--r-- | tools/perf/util/evsel.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 5ecf8f836f30..2a1729e7aee4 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -2847,9 +2847,23 @@ static bool find_process(const char *name) return ret ? false : true; } +static bool is_amd(const char *arch, const char *cpuid) +{ + return arch && !strcmp("x86", arch) && cpuid && strstarts(cpuid, "AuthenticAMD"); +} + +static bool is_amd_ibs(struct evsel *evsel) +{ + return evsel->core.attr.precise_ip + || (evsel->pmu_name && !strncmp(evsel->pmu_name, "ibs", 3)); +} + int evsel__open_strerror(struct evsel *evsel, struct target *target, int err, char *msg, size_t size) { + struct perf_env *env = evsel__env(evsel); + const char *arch = perf_env__arch(env); + const char *cpuid = perf_env__cpuid(env); char sbuf[STRERR_BUFSIZE]; int printed = 0, enforced = 0; @@ -2953,6 +2967,17 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target, return scnprintf(msg, size, "Invalid event (%s) in per-thread mode, enable system wide with '-a'.", evsel__name(evsel)); + if (is_amd(arch, cpuid)) { + if (is_amd_ibs(evsel)) { + if (evsel->core.attr.exclude_kernel) + return scnprintf(msg, size, + "AMD IBS can't exclude kernel events. Try running at a higher privilege level."); + if (!evsel->core.system_wide) + return scnprintf(msg, size, + "AMD IBS may only be available in system-wide/per-cpu mode. Try using -a, or -C and workload affinity"); + } + } + break; case ENODATA: return scnprintf(msg, size, "Cannot collect data source with the load latency event alone. " |