Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20221129120149.1035444-1-peternewman@google.com> <20221129120149.1035444-3-peternewman@google.com>
In-Reply-To: <20221129120149.1035444-3-peternewman@google.com>
From:   Peter Newman <peternewman@google.com>
Date:   Fri, 16 Dec 2022 16:12:45 +0100
Message-ID: <CALPaoCgQQGEypbEz_YMsq9+grM9bEKprVz+iByDUPh85acRM4g@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] x86/resctrl: Implement rename op for mon groups
To:     fenghua.yu@intel.com, reinette.chatre@intel.com
Cc:     Babu.Moger@amd.com, bp@alien8.de, dave.hansen@linux.intel.com,
        eranian@google.com, gupasani@google.com, hpa@zytor.com,
        james.morse@arm.com, linux-kernel@vger.kernel.org,
        mingo@redhat.com, tglx@linutronix.de, x86@kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, Nov 29, 2022 at 1:02 PM Peter Newman <peternewman@google.com> wrote:
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 03b51543c26d..d6562d98b816 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -3230,6 +3230,71 @@ static int rdtgroup_rmdir(struct kernfs_node *kn)
>         return ret;
>  }
>
> +static void mongrp_move(struct rdtgroup *rdtgrp, struct rdtgroup *new_prdtgrp)
> +{
> +       struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
> +       struct task_struct *p, *t;
> +
> +       WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
> +       list_del(&rdtgrp->mon.crdtgrp_list);
> +
> +       list_add_tail(&rdtgrp->mon.crdtgrp_list,
> +                     &new_prdtgrp->mon.crdtgrp_list);
> +       rdtgrp->mon.parent = new_prdtgrp;
> +
> +       read_lock(&tasklist_lock);
> +       for_each_process_thread(p, t) {
> +               if (is_closid_match(t, prdtgrp) && is_rmid_match(t, rdtgrp))
> +                       WRITE_ONCE(t->closid, new_prdtgrp->closid);
> +       }
> +       read_unlock(&tasklist_lock);
> +
> +       update_closid_rmid(cpu_online_mask, NULL);

I will need to refresh this patch now that we're back to building an
update mask.

This will once again depend on
https://lore.kernel.org/lkml/20221216133125.3159406-1-peternewman@google.com/