summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/cpu/resctrl
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/cpu/resctrl')
-rw-r--r--arch/x86/kernel/cpu/resctrl/monitor.c11
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 2cd25a0d4637..fe1a2aa53c16 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -458,7 +458,16 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
r->mon.mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
}
- if (rdt_cpu_has(X86_FEATURE_ABMC)) {
+ /*
+ * resctrl assumes a system that supports assignable counters can
+ * switch to "default" mode. Ensure that there is a "default" mode
+ * to switch to. This enforces a dependency between the independent
+ * X86_FEATURE_ABMC and X86_FEATURE_CQM_MBM_TOTAL/X86_FEATURE_CQM_MBM_LOCAL
+ * hardware features.
+ */
+ if (rdt_cpu_has(X86_FEATURE_ABMC) &&
+ (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL) ||
+ rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))) {
r->mon.mbm_cntr_assignable = true;
cpuid_count(0x80000020, 5, &eax, &ebx, &ecx, &edx);
r->mon.num_mbm_cntrs = (ebx & GENMASK(15, 0)) + 1;