diff options
| author | Reinette Chatre <reinette.chatre@intel.com> | 2020-05-05 15:36:17 -0700 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-05-06 18:02:41 +0200 |
| commit | f3d44f18b0662327c42128b9d3604489bdb6e36f (patch) | |
| tree | aeced9ad25200b4d9c91667dba119f1995cd7a8a /arch/x86/kernel/cpu/resctrl | |
| parent | 46637d4570e108d1f6721cfa2cca1d078882761a (diff) | |
x86/resctrl: Support CPUID enumeration of MBM counter width
The original Memory Bandwidth Monitoring (MBM) architectural
definition defines counters of up to 62 bits in the
IA32_QM_CTR MSR while the first-generation MBM implementation
uses statically defined 24 bit counters.
Expand the MBM CPUID enumeration properties to include the MBM
counter width. The previously undefined EAX output register contains,
in bits [7:0], the MBM counter width encoded as an offset from
24 bits. Enumerating this property is only specified for Intel
CPUs.
Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/afa3af2f753f6bc301fb743bc8944e749cb24afa.1588715690.git.reinette.chatre@intel.com
Diffstat (limited to 'arch/x86/kernel/cpu/resctrl')
| -rw-r--r-- | arch/x86/kernel/cpu/resctrl/core.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index d5979073301e..12f967c6b603 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -964,6 +964,7 @@ void resctrl_cpu_detect(struct cpuinfo_x86 *c) if (!cpu_has(c, X86_FEATURE_CQM_LLC)) { c->x86_cache_max_rmid = -1; c->x86_cache_occ_scale = -1; + c->x86_cache_mbm_width_offset = -1; return; } @@ -980,6 +981,10 @@ void resctrl_cpu_detect(struct cpuinfo_x86 *c) c->x86_cache_max_rmid = ecx; c->x86_cache_occ_scale = ebx; + if (c->x86_vendor == X86_VENDOR_INTEL) + c->x86_cache_mbm_width_offset = eax & 0xff; + else + c->x86_cache_mbm_width_offset = -1; } } |