[PATCH v4] perf/x86/intel/uncore: Fix CAS_COUNT_WRITE issue for ICX

[PATCH v4] perf/x86/intel/uncore: Fix CAS_COUNT_WRITE issue for ICX

[zhengjun.xing]

From: Zhengjun Xing <zhengjun.xing@linux.intel.com>

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")
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Cc: stable@vger.kernel.org
---
Change log:
  
  v4:
    * update commit log as Kan's suggestion

  v3:
    * Add change log

  v2:
    * Add stable tag

 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 3660f698fb2a..ed869443efb2 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,
-- 
2.25.1

[tip: perf/urgent] perf/x86/intel/uncore: Fix CAS_COUNT_WRITE issue for ICX

[tip-bot2 for Zhengjun Xing]

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.com
---
 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,