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| author | Fenghua Yu <fenghua.yu@intel.com> | 2020-10-14 03:49:27 +0300 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-10-27 20:57:22 +0300 |
| commit | 4868a61d498af3627c3b571aa48107a845001e51 (patch) | |
| tree | 50d045d4d80dde9aa5f3a4349ad333d48aa184f6 /arch/x86/kernel/cpu/resctrl/core.c | |
| parent | d1b22e36e3188f47dbf8aaef54d9e79df8e91f4c (diff) | |
| download | linux-4868a61d498af3627c3b571aa48107a845001e51.tar.xz | |
x86/resctrl: Correct MBM total and local values
Intel Memory Bandwidth Monitoring (MBM) counters may report system
memory bandwidth incorrectly on some Intel processors. The errata SKX99
for Skylake server, BDF102 for Broadwell server, and the correction
factor table are documented in Documentation/x86/resctrl.rst.
Intel MBM counters track metrics according to the assigned Resource
Monitor ID (RMID) for that logical core. The IA32_QM_CTR register
(MSR 0xC8E) used to report these metrics, may report incorrect system
bandwidth for certain RMID values.
Due to the errata, system memory bandwidth may not match what is
reported.
To work around the errata, correct MBM total and local readings using a
correction factor table. If rmid > rmid threshold, MBM total and local
values should be multiplied by the correction factor.
[ bp: Mark mbm_cf_table[] __initdata. ]
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20201014004927.1839452-3-fenghua.yu@intel.com
Diffstat (limited to 'arch/x86/kernel/cpu/resctrl/core.c')
| -rw-r--r-- | arch/x86/kernel/cpu/resctrl/core.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index e5f4ee8f4c3b..1a681fde4c51 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -893,6 +893,10 @@ static __init void __check_quirks_intel(void) set_rdt_options("!cmt,!mbmtotal,!mbmlocal,!l3cat"); else set_rdt_options("!l3cat"); + fallthrough; + case INTEL_FAM6_BROADWELL_X: + intel_rdt_mbm_apply_quirk(); + break; } } |