The RDT_RESOURCE_PERF_PKG resource is not marked as "mon_capable" during
early resctrl initialization. This means that the domain lists for the
resource are not built when the CPU hot plug notifiers are registered.
Set the global rdt_mon_capable (to cover the case when none of the L3
monitor events are enabled).
Mark the resource as mon_capable and call domain_add_cpu_mon() for
each online CPU to build the domain lists in the first call to the
resctrl_arch_pre_mount() hook.
Signed-off-by: Tony Luck <tony.luck@intel.com>
---
arch/x86/kernel/cpu/resctrl/core.c | 17 ++++++++++++++++-
arch/x86/kernel/cpu/resctrl/intel_aet.c | 4 ++++
2 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 0284da075ea6..d1e2c5e2501f 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -750,14 +750,29 @@ static int resctrl_arch_offline_cpu(unsigned int cpu)
void resctrl_arch_pre_mount(void)
{
+ struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_PERF_PKG].r_resctrl;
static atomic_t only_once = ATOMIC_INIT(0);
- int old = 0;
+ int cpu, old = 0;
if (!atomic_try_cmpxchg(&only_once, &old, 1))
return;
if (!intel_aet_get_events())
return;
+
+ if (!r->mon_capable)
+ return;
+
+ /*
+ * Late discovery of telemetry events means the domains for the
+ * resource were not built. Do that now.
+ */
+ cpus_read_lock();
+ mutex_lock(&domain_list_lock);
+ for_each_online_cpu(cpu)
+ domain_add_cpu_mon(cpu, r);
+ mutex_unlock(&domain_list_lock);
+ cpus_read_unlock();
}
enum {
diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
index 96c454748320..4afc99e74cef 100644
--- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
+++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
@@ -258,6 +258,10 @@ static int discover_events(struct event_group *e, struct pmt_feature_group *p)
else
r->num_rmid = e->num_rmids;
+ pr_info("%s %s monitoring detected\n", r->name, e->name);
+ r->mon_capable = true;
+ rdt_mon_capable = true;
+
return 0;
}
--
2.50.1