Hi Babu,
On 10/9/24 10:39 AM, Babu Moger wrote:
> Assign/unassign counters on resctrl group creation/deletion. Two counters
> are required per group, one for MBM total event and one for MBM local
> event.
>
> There are a limited number of counters available for assignment. If these
> counters are exhausted, the kernel will display the error message: "Out of
> MBM assignable counters". However, it is not necessary to fail the
> creation of a group due to assignment failures. Users have the flexibility
> to modify the assignments at a later time.
>
> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> ---
...
> ---
> arch/x86/kernel/cpu/resctrl/rdtgroup.c | 64 ++++++++++++++++++++++++++
> 1 file changed, 64 insertions(+)
>
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 791258adcbda..cb2c60c0319e 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
...
> static int rdt_get_tree(struct fs_context *fc)
> {
> struct rdt_fs_context *ctx = rdt_fc2context(fc);
> @@ -2934,6 +2980,8 @@ static int rdt_get_tree(struct fs_context *fc)
> if (ret < 0)
> goto out_mongrp;
> rdtgroup_default.mon.mon_data_kn = kn_mondata;
> +
> + rdtgroup_assign_cntrs(&rdtgroup_default);
> }
>
> ret = rdt_pseudo_lock_init();
> @@ -2964,6 +3012,7 @@ static int rdt_get_tree(struct fs_context *fc)
> out_psl:
> rdt_pseudo_lock_release();
> out_mondata:
> + rdtgroup_unassign_cntrs(&rdtgroup_default);
> if (resctrl_arch_mon_capable())
> kernfs_remove(kn_mondata);
I think I mentioned this before ... this addition belongs within the
"if (resctrl_arch_mon_capable())" to be symmetrical with where it was called from.
> out_mongrp:
> @@ -3144,6 +3193,7 @@ static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
>
> head = &rdtgrp->mon.crdtgrp_list;
> list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) {
> + rdtgroup_unassign_cntrs(sentry);
> free_rmid(sentry->closid, sentry->mon.rmid);
> list_del(&sentry->mon.crdtgrp_list);
>
> @@ -3184,6 +3234,8 @@ static void rmdir_all_sub(void)
> cpumask_or(&rdtgroup_default.cpu_mask,
> &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
>
> + rdtgroup_unassign_cntrs(rdtgrp);
> +
> free_rmid(rdtgrp->closid, rdtgrp->mon.rmid);
>
> kernfs_remove(rdtgrp->kn);
> @@ -3223,6 +3275,8 @@ static void rdt_kill_sb(struct super_block *sb)
> resctrl_arch_disable_alloc();
> if (resctrl_arch_mon_capable())
> resctrl_arch_disable_mon();
> +
> + rdtgroup_unassign_cntrs(&rdtgroup_default);
Unassigning counters after monitoring is completely disabled seems late. I
think this can be moved earlier to be right after the counters of all the
other groups are unassigned.
> resctrl_mounted = false;
> kernfs_kill_sb(sb);
> mutex_unlock(&rdtgroup_mutex);
> @@ -3814,6 +3868,8 @@ static int rdtgroup_mkdir_mon(struct kernfs_node *parent_kn,
> goto out_unlock;
> }
>
> + rdtgroup_assign_cntrs(rdtgrp);
> +
> kernfs_activate(rdtgrp->kn);
>
> /*
> @@ -3858,6 +3914,8 @@ static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
> if (ret)
> goto out_closid_free;
>
> + rdtgroup_assign_cntrs(rdtgrp);
> +
> kernfs_activate(rdtgrp->kn);
>
> ret = rdtgroup_init_alloc(rdtgrp);
> @@ -3883,6 +3941,7 @@ static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
> out_del_list:
> list_del(&rdtgrp->rdtgroup_list);
> out_rmid_free:
> + rdtgroup_unassign_cntrs(rdtgrp);
> mkdir_rdt_prepare_rmid_free(rdtgrp);
> out_closid_free:
> closid_free(closid);
> @@ -3953,6 +4012,9 @@ static int rdtgroup_rmdir_mon(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
> update_closid_rmid(tmpmask, NULL);
>
> rdtgrp->flags = RDT_DELETED;
> +
> + rdtgroup_unassign_cntrs(rdtgrp);
> +
> free_rmid(rdtgrp->closid, rdtgrp->mon.rmid);
>
> /*
> @@ -3999,6 +4061,8 @@ static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
> cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
> update_closid_rmid(tmpmask, NULL);
>
> + rdtgroup_unassign_cntrs(rdtgrp);
> +
> free_rmid(rdtgrp->closid, rdtgrp->mon.rmid);
> closid_free(rdtgrp->closid);
>
Reinette
