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| author | Adrian Hunter <adrian.hunter@intel.com> | 2018-11-26 14:12:52 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-26 09:38:34 +0100 |
| commit | 9da7dfdb8d97ea40cb4db8f722a78d6db3dff34f (patch) | |
| tree | 40a7849e5abc65d5d7bd68548d48d6693129d835 /tools | |
| parent | 80c8e52837206e5c61cffd35183798b64e659675 (diff) | |
| download | linux-stable-9da7dfdb8d97ea40cb4db8f722a78d6db3dff34f.tar.gz linux-stable-9da7dfdb8d97ea40cb4db8f722a78d6db3dff34f.tar.bz2 linux-stable-9da7dfdb8d97ea40cb4db8f722a78d6db3dff34f.zip | |
perf intel-pt: Fix error with config term "pt=0"
[ Upstream commit 1c6f709b9f96366cc47af23c05ecec9b8c0c392d ]
Users should never use 'pt=0', but if they do it may give a meaningless
error:
$ perf record -e intel_pt/pt=0/u uname
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for
event (intel_pt/pt=0/u).
Fix that by forcing 'pt=1'.
Committer testing:
# perf record -e intel_pt/pt=0/u uname
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (intel_pt/pt=0/u).
/bin/dmesg | grep -i perf may provide additional information.
# perf record -e intel_pt/pt=0/u uname
pt=0 doesn't make sense, forcing pt=1
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.020 MB perf.data ]
#
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/b7c5b4e5-9497-10e5-fd43-5f3e4a0fe51d@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/arch/x86/util/intel-pt.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/tools/perf/arch/x86/util/intel-pt.c b/tools/perf/arch/x86/util/intel-pt.c index 90fa2286edcf..c88adcbf966e 100644 --- a/tools/perf/arch/x86/util/intel-pt.c +++ b/tools/perf/arch/x86/util/intel-pt.c @@ -522,10 +522,21 @@ static int intel_pt_validate_config(struct perf_pmu *intel_pt_pmu, struct perf_evsel *evsel) { int err; + char c; if (!evsel) return 0; + /* + * If supported, force pass-through config term (pt=1) even if user + * sets pt=0, which avoids senseless kernel errors. + */ + if (perf_pmu__scan_file(intel_pt_pmu, "format/pt", "%c", &c) == 1 && + !(evsel->attr.config & 1)) { + pr_warning("pt=0 doesn't make sense, forcing pt=1\n"); + evsel->attr.config |= 1; + } + err = intel_pt_val_config_term(intel_pt_pmu, "caps/cycle_thresholds", "cyc_thresh", "caps/psb_cyc", evsel->attr.config); |