diff options
author | Kim Phillips <kim.phillips@amd.com> | 2020-03-11 14:13:21 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-20 09:06:33 +0100 |
commit | d02a763751555c8ec2933b759c19bf3e43ac072e (patch) | |
tree | fedab9e878b5ce106ab8ab9d667d73b1b58d170e | |
parent | d1ff9467237281fe23a4654e64bbedcbc6f5c801 (diff) |
perf/amd/uncore: Replace manual sampling check with CAP_NO_INTERRUPT flag
[ Upstream commit f967140dfb7442e2db0868b03b961f9c59418a1b ]
Enable the sampling check in kernel/events/core.c::perf_event_open(),
which returns the more appropriate -EOPNOTSUPP.
BEFORE:
$ sudo perf record -a -e instructions,l3_request_g1.caching_l3_cache_accesses true
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (l3_request_g1.caching_l3_cache_accesses).
/bin/dmesg | grep -i perf may provide additional information.
With nothing relevant in dmesg.
AFTER:
$ sudo perf record -a -e instructions,l3_request_g1.caching_l3_cache_accesses true
Error:
l3_request_g1.caching_l3_cache_accesses: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'
Fixes: c43ca5091a37 ("perf/x86/amd: Add support for AMD NB and L2I "uncore" counters")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200311191323.13124-1-kim.phillips@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | arch/x86/kernel/cpu/perf_event_amd_uncore.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_amd_uncore.c b/arch/x86/kernel/cpu/perf_event_amd_uncore.c index 49742746a6c9..98e786a779fd 100644 --- a/arch/x86/kernel/cpu/perf_event_amd_uncore.c +++ b/arch/x86/kernel/cpu/perf_event_amd_uncore.c @@ -181,21 +181,19 @@ static int amd_uncore_event_init(struct perf_event *event) return -ENOENT; /* - * NB and L2 counters (MSRs) are shared across all cores that share the - * same NB / L2 cache. Interrupts can be directed to a single target - * core, however, event counts generated by processes running on other - * cores cannot be masked out. So we do not support sampling and - * per-thread events. + * NB and Last level cache counters (MSRs) are shared across all cores + * that share the same NB / Last level cache. On family 16h and below, + * Interrupts can be directed to a single target core, however, event + * counts generated by processes running on other cores cannot be masked + * out. So we do not support sampling and per-thread events via + * CAP_NO_INTERRUPT, and we do not enable counter overflow interrupts: */ - if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK) - return -EINVAL; /* NB and L2 counters do not have usr/os/guest/host bits */ if (event->attr.exclude_user || event->attr.exclude_kernel || event->attr.exclude_host || event->attr.exclude_guest) return -EINVAL; - /* and we do not enable counter overflow interrupts */ hwc->config = event->attr.config & AMD64_RAW_EVENT_MASK_NB; hwc->idx = -1; @@ -271,6 +269,7 @@ static struct pmu amd_nb_pmu = { .start = amd_uncore_start, .stop = amd_uncore_stop, .read = amd_uncore_read, + .capabilities = PERF_PMU_CAP_NO_INTERRUPT, }; static struct pmu amd_l2_pmu = { @@ -282,6 +281,7 @@ static struct pmu amd_l2_pmu = { .start = amd_uncore_start, .stop = amd_uncore_stop, .read = amd_uncore_read, + .capabilities = PERF_PMU_CAP_NO_INTERRUPT, }; static struct amd_uncore *amd_uncore_alloc(unsigned int cpu) |