On 11/18/2021 11:02 AM, zhengjun.xing@linux.intel.com wrote:
From: Zhengjun Xing zhengjun.xing@linux.intel.com
The user recently report a perf issue in the ICX platform, when test by
If you have the user's name, you may want to add a Reported-by tag to give them credit. If you don't have, it doesn't matter either.
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:
https://www.intel.com/content/www/us/en/develop/download/3rd-gen-intel-xeon-...
On page 142, Table 2-143, defines Unit Masks for CAS_COUNT: RD b00001111 WR b00110000
I think we usually want a permanent reference in the change log. The document may be updated later. The page number or the table number may not be accurate anymore.
I guess you may want to give the exact document name and the version number here. So people can still easily locate the information several years later. E.g., "3rd Gen Intel® Xeon® Processor Scalable Family, Codename Ice Lake, Uncore Performance Monitoring Reference Manual, Revision 1.00, May 2021"
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
Other than the above comments, the patch looks good to me.
Reviewed-by: Kan Liang kan.liang@linux.intel.com
Thanks, Kan
Signed-off-by: Zhengjun Xing zhengjun.xing@linux.intel.com Cc: stable@vger.kernel.org
Change log:
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 5ddc0f30db6f..a6fd8eb410a9 100644 --- a/arch/x86/events/intel/uncore_snbep.c +++ b/arch/x86/events/intel/uncore_snbep.c @@ -5468,7 +5468,7 @@ 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,