x86/resctrl: Refactor domain_remove_cpu_mon() ready for new domain types

New telemetry events will be associated with a new package scoped resource
with a new domain structure.

Refactor domain_remove_cpu_mon() so all the L3 domain processing is separate
from the general domain action of clearing the CPU bit in the mask.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 2a568b31671121a2ef4446d786020672e809f1d7..49b133e847d4cc416cf576283bbb5e6cba790a92 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -631,9 +631,7 @@ static void domain_remove_cpu_ctrl(int cpu, struct rdt_resource *r)
 static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
 {
        int id = get_domain_id_from_scope(cpu, r->mon_scope);
-       struct rdt_hw_mon_domain *hw_dom;
        struct rdt_domain_hdr *hdr;
-       struct rdt_mon_domain *d;
 
        lockdep_assert_held(&domain_list_lock);
 
@@ -650,20 +648,29 @@ static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
                return;
        }
 
-       if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, r->rid))
+       cpumask_clear_cpu(cpu, &hdr->cpu_mask);
+       if (!cpumask_empty(&hdr->cpu_mask))
                return;
 
-       d = container_of(hdr, struct rdt_mon_domain, hdr);
-       hw_dom = resctrl_to_arch_mon_dom(d);
+       switch (r->rid) {
+       case RDT_RESOURCE_L3: {
+               struct rdt_hw_mon_domain *hw_dom;
+               struct rdt_mon_domain *d;
 
-       cpumask_clear_cpu(cpu, &d->hdr.cpu_mask);
-       if (cpumask_empty(&d->hdr.cpu_mask)) {
+               if (!domain_header_is_valid(hdr, RESCTRL_MON_DOMAIN, RDT_RESOURCE_L3))
+                       return;
+
+               d = container_of(hdr, struct rdt_mon_domain, hdr);
+               hw_dom = resctrl_to_arch_mon_dom(d);
                resctrl_offline_mon_domain(r, d);
-               list_del_rcu(&d->hdr.list);
+               list_del_rcu(&hdr->list);
                synchronize_rcu();
                mon_domain_free(hw_dom);
-
-               return;
+               break;
+       }
+       default:
+               pr_warn_once("Unknown resource rid=%d\n", r->rid);
+               break;
        }
 }