[PATCH v9 23/26] x86/resctrl: Configure mbm_cntr_assign mode if supported

Babu Moger posted 26 patches 3 weeks, 5 days ago
[PATCH v9 23/26] x86/resctrl: Configure mbm_cntr_assign mode if supported
Posted by Babu Moger 3 weeks, 5 days ago
Configure mbm_cntr_assign on AMD. 'mbm_cntr_assign' mode in AMD is ABMC
(Assignable Bandwidth Monitoring Counters). It is enabled by default when
supported on the system.

When the ABMC is updated, it must be updated on all the logical processors
in the resctrl domain.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
v9: Minor code change due to merge. Actual code did not change.

v8: Renamed resctrl_arch_mbm_cntr_assign_configure to
	resctrl_arch_mbm_cntr_assign_set_one.
    Adde r->mon_capable check.
    Commit message update.

v7: Introduced resctrl_arch_mbm_cntr_assign_configure() to configure.
    Moved the default settings to rdt_get_mon_l3_config(). It should be
    done before the hotplug handler is called. It cannot be done at
    rdtgroup_init().

v6: Keeping the default enablement in arch init code for now.
     This may need some discussion.
     Renamed resctrl_arch_configure_abmc to resctrl_arch_mbm_cntr_assign_configure.

v5: New patch to enable ABMC by default.
---
 arch/x86/kernel/cpu/resctrl/internal.h |  1 +
 arch/x86/kernel/cpu/resctrl/monitor.c  |  1 +
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 11 +++++++++++
 3 files changed, 13 insertions(+)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 66de0ce12aba..b90d8c90b4b6 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -721,6 +721,7 @@ int rdtgroup_assign_cntr_event(struct rdt_resource *r, struct rdtgroup *rdtgrp,
 			       struct rdt_mon_domain *d, enum resctrl_event_id evtid);
 int rdtgroup_unassign_cntr_event(struct rdt_resource *r, struct rdtgroup *rdtgrp,
 				 struct rdt_mon_domain *d, enum resctrl_event_id evtid);
+void resctrl_arch_mbm_cntr_assign_set_one(struct rdt_resource *r);
 void rdt_staged_configs_clear(void);
 bool closid_allocated(unsigned int closid);
 int resctrl_find_cleanest_closid(void);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index e8d38a963f39..4ba5007fd1aa 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1267,6 +1267,7 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 			r->mon.mbm_cntr_assignable = true;
 			cpuid_count(0x80000020, 5, &eax, &ebx, &ecx, &edx);
 			r->mon.num_mbm_cntrs = (ebx & GENMASK(15, 0)) + 1;
+			hw_res->mbm_cntr_assign_enabled = true;
 			resctrl_file_fflags_init("num_mbm_cntrs", RFTYPE_MON_INFO);
 			resctrl_file_fflags_init("available_mbm_cntrs", RFTYPE_MON_INFO);
 		}
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 7fa6a86c6ca8..5b8bb8bd913c 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2799,6 +2799,13 @@ int resctrl_arch_mbm_cntr_assign_set(struct rdt_resource *r, bool enable)
 	return 0;
 }
 
+void resctrl_arch_mbm_cntr_assign_set_one(struct rdt_resource *r)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+	resctrl_abmc_set_one_amd(&hw_res->mbm_cntr_assign_enabled);
+}
+
 /*
  * We don't allow rdtgroup directories to be created anywhere
  * except the root directory. Thus when looking for the rdtgroup
@@ -4582,9 +4589,13 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d)
 
 void resctrl_online_cpu(unsigned int cpu)
 {
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+
 	mutex_lock(&rdtgroup_mutex);
 	/* The CPU is set in default rdtgroup after online. */
 	cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask);
+	if (r->mon_capable && r->mon.mbm_cntr_assignable)
+		resctrl_arch_mbm_cntr_assign_set_one(r);
 	mutex_unlock(&rdtgroup_mutex);
 }
 
-- 
2.34.1
Re: [PATCH v9 23/26] x86/resctrl: Configure mbm_cntr_assign mode if supported
Posted by Reinette Chatre 6 days, 9 hours ago
Hi Babu,

On 10/29/24 4:21 PM, Babu Moger wrote:
> Configure mbm_cntr_assign on AMD. 'mbm_cntr_assign' mode in AMD is ABMC
> (Assignable Bandwidth Monitoring Counters). It is enabled by default when
> supported on the system.
> 
> When the ABMC is updated, it must be updated on all the logical processors
> in the resctrl domain.

This needs imperative tone.

Reinette
Re: [PATCH v9 23/26] x86/resctrl: Configure mbm_cntr_assign mode if supported
Posted by Moger, Babu 4 days, 9 hours ago
Hi Reinette,

On 11/18/24 13:23, Reinette Chatre wrote:
> Hi Babu,
> 
> On 10/29/24 4:21 PM, Babu Moger wrote:
>> Configure mbm_cntr_assign on AMD. 'mbm_cntr_assign' mode in AMD is ABMC
>> (Assignable Bandwidth Monitoring Counters). It is enabled by default when
>> supported on the system.
>>
>> When the ABMC is updated, it must be updated on all the logical processors
>> in the resctrl domain.
> 
> This needs imperative tone.
> 

Ensure that the ABMC is updated on all logical processors in the resctrl
domain.

-- 
Thanks
Babu Moger