Hi Babu,
On 06/08/2024 23:00, Babu Moger wrote:
> Enable ABMC by default when supported during the boot up.
>
> Users will not see any difference in the behavior when resctrl is
> mounted. With automatic assignment everything will work as running
> in the legacy monitor mode.
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index 6fb0cfdb5529..a7980f84c487 100644
> --- a/arch/x86/kernel/cpu/resctrl/core.c
> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> @@ -599,6 +599,7 @@ static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
> d = container_of(hdr, struct rdt_mon_domain, hdr);
>
> cpumask_set_cpu(cpu, &d->hdr.cpu_mask);
> + resctrl_arch_mbm_cntr_assign_configure();
> return;
> }
>
> @@ -620,6 +621,7 @@ static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
> arch_mon_domain_online(r, d);
>
> resctrl_mbm_evt_config_init(hw_dom);
> + resctrl_arch_mbm_cntr_assign_configure();
>
> if (arch_domain_mbm_alloc(r->mon.num_rmid, hw_dom)) {
> mon_domain_free(hw_dom);
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 66febff2a3d3..d15fd1bde5f4 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -2756,6 +2756,23 @@ void resctrl_arch_mbm_cntr_assign_disable(void)
> }
> }
>
> +void resctrl_arch_mbm_cntr_assign_configure(void)
> +{
> + struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
> + struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
> + bool enable = true;
> +
> + mutex_lock(&rdtgroup_mutex);
As before - this lock isn't available to the architecture code after the filesystem code
moves to /fs/. To prevent concurrent calls to resctrl_abmc_set_one_amd() I think you need
your own mutex.
> + if (r->mon.mbm_cntr_assignable) {
> + if (!hw_res->mbm_cntr_assign_enabled)
> + hw_res->mbm_cntr_assign_enabled = true;
> + resctrl_abmc_set_one_amd(&enable);
> + }
> +
> + mutex_unlock(&rdtgroup_mutex);
> +}
Neither of this functions callers are in filesystem code, could you drop the 'arch' from
the name - it isn't part of the fs/arch interface.
Thanks,
James
