The following commit has been merged into the perf/urgent branch of tip:
Commit-ID: 96fd2e89fba1aaada6f4b1e5d25a9d9ecbe1943d Gitweb: https://git.kernel.org/tip/96fd2e89fba1aaada6f4b1e5d25a9d9ecbe1943d Author: Zhengjun Xing zhengjun.xing@linux.intel.com AuthorDate: Thu, 23 Dec 2021 22:48:26 +08:00 Committer: Peter Zijlstra peterz@infradead.org CommitterDate: Tue, 18 Jan 2022 12:09:48 +01:00
perf/x86/intel/uncore: Fix CAS_COUNT_WRITE issue for ICX
The user recently report a perf issue in the ICX platform, when test by perf event “uncore_imc_x/cas_count_write”,the write bandwidth is always very small (only 0.38MB/s), it is caused by the wrong "umask" for the "cas_count_write" event. When double-checking, find "cas_count_read" also is wrong.
The public document for ICX uncore:
3rd Gen Intel® Xeon® Processor Scalable Family, Codename Ice Lake,Uncore Performance Monitoring Reference Manual, Revision 1.00, May 2021
On 2.4.7, it defines Unit Masks for CAS_COUNT: RD b00001111 WR b00110000
So corrected both "cas_count_read" and "cas_count_write" for ICX.
Old settings: hswep_uncore_imc_events INTEL_UNCORE_EVENT_DESC(cas_count_read, "event=0x04,umask=0x03") INTEL_UNCORE_EVENT_DESC(cas_count_write, "event=0x04,umask=0x0c")
New settings: snr_uncore_imc_events INTEL_UNCORE_EVENT_DESC(cas_count_read, "event=0x04,umask=0x0f") INTEL_UNCORE_EVENT_DESC(cas_count_write, "event=0x04,umask=0x30")
Fixes: 2b3b76b5ec67 ("perf/x86/intel/uncore: Add Ice Lake server uncore support") Signed-off-by: Zhengjun Xing zhengjun.xing@linux.intel.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Reviewed-by: Adrian Hunter adrian.hunter@intel.com Reviewed-by: Kan Liang kan.liang@linux.intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20211223144826.841267-1-zhengjun.xing@linux.intel.... --- arch/x86/events/intel/uncore_snbep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c index 3660f69..ed86944 100644 --- a/arch/x86/events/intel/uncore_snbep.c +++ b/arch/x86/events/intel/uncore_snbep.c @@ -5482,7 +5482,7 @@ static struct intel_uncore_type icx_uncore_imc = { .fixed_ctr_bits = 48, .fixed_ctr = SNR_IMC_MMIO_PMON_FIXED_CTR, .fixed_ctl = SNR_IMC_MMIO_PMON_FIXED_CTL, - .event_descs = hswep_uncore_imc_events, + .event_descs = snr_uncore_imc_events, .perf_ctr = SNR_IMC_MMIO_PMON_CTR0, .event_ctl = SNR_IMC_MMIO_PMON_CTL0, .event_mask = SNBEP_PMON_RAW_EVENT_MASK,