Jin Yao c4735d9902 perf evsel: Don't set sample_regs_intr/sample_regs_user for dummy event ... Since commit 0a892c1c94 ("perf record: Add dummy event during system wide synthesis"), a dummy event is added to capture mmaps. But if we run perf-record as, # perf record -e cycles:p -IXMM0 -a -- sleep 1 Error: dummy:HG: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' The issue is, if we enable the extended regs (-IXMM0), but the pmu->capabilities is not set with PERF_PMU_CAP_EXTENDED_REGS, the kernel will return -EOPNOTSUPP error. See following code: /* in kernel/events/core.c */ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) { .... if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && has_extended_regs(event)) ret = -EOPNOTSUPP; .... } For software dummy event, the PMU should not be set with PERF_PMU_CAP_EXTENDED_REGS. But unfortunately now, the dummy event has possibility to be set with PERF_REG_EXTENDED_MASK bit. In evsel__config, /* tools/perf/util/evsel.c */ if (opts->sample_intr_regs) { attr->sample_regs_intr = opts->sample_intr_regs; } If we use -IXMM0, the attr>sample_regs_intr will be set with PERF_REG_EXTENDED_MASK bit. It doesn't make sense to set attr->sample_regs_intr for a software dummy event. This patch adds dummy event checking before setting attr->sample_regs_intr and attr->sample_regs_user. After: # ./perf record -e cycles:p -IXMM0 -a -- sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.413 MB perf.data (45 samples) ] Committer notes: Adrian said this when providing his Acked-by: " This is fine. It will not break PT. no_aux_samples is useful for evsels that have been added by the code rather than requested by the user. For old kernels PT adds sched_switch tracepoint to track context switches (before the current context switch event was added) and having auxiliary sample information unnecessarily uses up space in the perf buffer. " Fixes: 0a892c1c94 ("perf record: Add dummy event during system wide synthesis") Signed-off-by: Jin Yao <yao.jin@linux.intel.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jin Yao <yao.jin@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20200720010013.18238-1-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>		2020-08-04 09:04:31 -03:00
..
accounting
arch	tools arch kvm: Sync kvm headers with the kernel sources	2020-07-17 09:39:16 -03:00
bootconfig	tools/bootconfig: Add testcase for show-command and quotes test	2020-06-16 21:21:03 -04:00
bpf	tools, bpftool: Add ringbuf map type to map command docs	2020-06-17 17:52:30 +02:00
build	tools build feature: Use CC and CXX from parent	2020-07-31 09:27:58 -03:00
cgroup	Merge branch 'block-5.7' into for-5.8/block	2020-05-09 16:13:58 -06:00
debugging
edid
firewire
firmware
gpio	tools: gpio: add bias flags to lsgpio	2020-05-05 18:27:09 +02:00
hv
iio
include	Merge remote-tracking branch 'torvalds/master' into perf/core	2020-08-03 09:37:31 -03:00
io_uring
kvm/kvm_stat
laptop
leds
lib	Merge remote-tracking branch 'torvalds/master' into perf/core	2020-08-03 09:37:31 -03:00
memory-model
nfsd
objtool	Peter Zijlstra says:	2020-06-28 10:16:15 -07:00
pci
pcmcia
perf	perf evsel: Don't set sample_regs_intr/sample_regs_user for dummy event	2020-08-04 09:04:31 -03:00
power	Merge branch 'acpica'	2020-06-10 17:27:28 +02:00
scripts
spi	spi: tools: Make default_tx/rx and input_tx static	2020-06-11 16:27:24 +01:00
testing	Bugfixes and strengthening the validity checks on inputs from new userspace APIs.	2020-08-02 10:41:00 -07:00
thermal/tmon
time
usb
virtio	tools/virtio: Use tools/include/list.h instead of stubs	2020-06-22 12:34:22 -04:00
vm	tools/vm/page_owner_sort.c: filter out unneeded line	2020-06-03 20:09:49 -07:00
wmi
Makefile