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authorKim Phillips <kim.phillips@amd.com>2020-03-11 14:13:21 -0500
committerBorislav Petkov <bp@suse.de>2020-03-12 14:08:50 +0100
commitf967140dfb7442e2db0868b03b961f9c59418a1b (patch)
treea1ab02af8622ba16f4df0964f77d0d12dd9213ce /arch/x86/events
parent798048f85093901f475d25b2ac8d9ea1bc6d471a (diff)
downloadlinux-f967140dfb7442e2db0868b03b961f9c59418a1b.tar.gz
perf/amd/uncore: Replace manual sampling check with CAP_NO_INTERRUPT flag
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
Diffstat (limited to 'arch/x86/events')
-rw-r--r--arch/x86/events/amd/uncore.c17
1 files changed, 7 insertions, 10 deletions
diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index a6ea07f2aa84..4d867a752f0e 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -190,15 +190,12 @@ static int amd_uncore_event_init(struct perf_event *event)
/*
* NB and Last level cache counters (MSRs) are shared across all cores
- * that share the same NB / Last level 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.
+ * 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;
-
- /* and we do not enable counter overflow interrupts */
hwc->config = event->attr.config & AMD64_RAW_EVENT_MASK_NB;
hwc->idx = -1;
@@ -306,7 +303,7 @@ static struct pmu amd_nb_pmu = {
.start = amd_uncore_start,
.stop = amd_uncore_stop,
.read = amd_uncore_read,
- .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE | PERF_PMU_CAP_NO_INTERRUPT,
};
static struct pmu amd_llc_pmu = {
@@ -317,7 +314,7 @@ static struct pmu amd_llc_pmu = {
.start = amd_uncore_start,
.stop = amd_uncore_stop,
.read = amd_uncore_read,
- .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE | PERF_PMU_CAP_NO_INTERRUPT,
};
static struct amd_uncore *amd_uncore_alloc(unsigned int cpu)