x86/resctrl: Add domain online callback for resctrl work

Because domains are exposed to user-space via resctrl, the filesystem
must update its state when CPU hotplug callbacks are triggered.

Some of this work is common to any architecture that would support
resctrl, but the work is tied up with the architecture code to
allocate the memory.

Move domain_setup_mon_state(), the monitor subdir creation call and the
mbm/limbo workers into a new resctrl_online_domain() call. These bits
are not specific to the architecture. Grouping them in one function
allows that code to be moved to /fs/ and re-used by another architecture.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jamie Iles <quic_jiles@quicinc.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Xin Hao <xhao@linux.alibaba.com>
Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20220902154829.30399-4-james.morse@arm.com

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 2f87177f1f695f4d9fb12679ac1d23d9fab9cdc9..25f30148478b821f00629cb067b46c370ba58236 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -443,42 +443,6 @@ static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
        return 0;
 }
 
-static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
-{
-       size_t tsize;
-
-       if (is_llc_occupancy_enabled()) {
-               d->rmid_busy_llc = bitmap_zalloc(r->num_rmid, GFP_KERNEL);
-               if (!d->rmid_busy_llc)
-                       return -ENOMEM;
-               INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
-       }
-       if (is_mbm_total_enabled()) {
-               tsize = sizeof(*d->mbm_total);
-               d->mbm_total = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
-               if (!d->mbm_total) {
-                       bitmap_free(d->rmid_busy_llc);
-                       return -ENOMEM;
-               }
-       }
-       if (is_mbm_local_enabled()) {
-               tsize = sizeof(*d->mbm_local);
-               d->mbm_local = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
-               if (!d->mbm_local) {
-                       bitmap_free(d->rmid_busy_llc);
-                       kfree(d->mbm_total);
-                       return -ENOMEM;
-               }
-       }
-
-       if (is_mbm_enabled()) {
-               INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
-               mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL);
-       }
-
-       return 0;
-}
-
 /*
  * domain_add_cpu - Add a cpu to a resource's domain list.
  *
@@ -498,6 +462,7 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
        struct list_head *add_pos = NULL;
        struct rdt_hw_domain *hw_dom;
        struct rdt_domain *d;
+       int err;
 
        d = rdt_find_domain(r, id, &add_pos);
        if (IS_ERR(d)) {
@@ -527,21 +492,15 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
                return;
        }
 
-       if (r->mon_capable && domain_setup_mon_state(r, d)) {
+       list_add_tail(&d->list, add_pos);
+
+       err = resctrl_online_domain(r, d);
+       if (err) {
+               list_del(&d->list);
                kfree(hw_dom->ctrl_val);
                kfree(hw_dom->mbps_val);
                kfree(hw_dom);
-               return;
        }
-
-       list_add_tail(&d->list, add_pos);
-
-       /*
-        * If resctrl is mounted, add
-        * per domain monitor data directories.
-        */
-       if (static_branch_unlikely(&rdt_mon_enable_key))
-               mkdir_mondata_subdir_allrdtgrp(r, d);
 }
 
 static void domain_remove_cpu(int cpu, struct rdt_resource *r)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 8828b5c1b6d2e098d46d22f4fa9d1ae8e51f31c5..be48a682dbdbe3182866e716b78c0c3b80e245eb 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -524,8 +524,6 @@ void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
 void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
                                    unsigned int dom_id);
-void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
-                                   struct rdt_domain *d);
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
                    struct rdt_domain *d, struct rdtgroup *rdtgrp,
                    int evtid, int first);

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index def7c6681f8b3aec967797560dfa06729aa8f0ce..030a70326ccc76a28b099d107df8b6099f40808b 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2565,16 +2565,13 @@ out_destroy:
  * Add all subdirectories of mon_data for "ctrl_mon" groups
  * and "monitor" groups with given domain id.
  */
-void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
-                                   struct rdt_domain *d)
+static void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+                                          struct rdt_domain *d)
 {
        struct kernfs_node *parent_kn;
        struct rdtgroup *prgrp, *crgrp;
        struct list_head *head;
 
-       if (!r->mon_capable)
-               return;
-
        list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
                parent_kn = prgrp->mon.mon_data_kn;
                mkdir_mondata_subdir(parent_kn, d, r, prgrp);
@@ -3236,6 +3233,64 @@ out:
        return ret;
 }
 
+static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
+{
+       size_t tsize;
+
+       if (is_llc_occupancy_enabled()) {
+               d->rmid_busy_llc = bitmap_zalloc(r->num_rmid, GFP_KERNEL);
+               if (!d->rmid_busy_llc)
+                       return -ENOMEM;
+       }
+       if (is_mbm_total_enabled()) {
+               tsize = sizeof(*d->mbm_total);
+               d->mbm_total = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+               if (!d->mbm_total) {
+                       bitmap_free(d->rmid_busy_llc);
+                       return -ENOMEM;
+               }
+       }
+       if (is_mbm_local_enabled()) {
+               tsize = sizeof(*d->mbm_local);
+               d->mbm_local = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+               if (!d->mbm_local) {
+                       bitmap_free(d->rmid_busy_llc);
+                       kfree(d->mbm_total);
+                       return -ENOMEM;
+               }
+       }
+
+       return 0;
+}
+
+int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d)
+{
+       int err;
+
+       lockdep_assert_held(&rdtgroup_mutex);
+
+       if (!r->mon_capable)
+               return 0;
+
+       err = domain_setup_mon_state(r, d);
+       if (err)
+               return err;
+
+       if (is_mbm_enabled()) {
+               INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
+               mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL);
+       }
+
+       if (is_llc_occupancy_enabled())
+               INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
+
+       /* If resctrl is mounted, add per domain monitor data directories. */
+       if (static_branch_unlikely(&rdt_mon_enable_key))
+               mkdir_mondata_subdir_allrdtgrp(r, d);
+
+       return 0;
+}
+
 /*
  * rdtgroup_init - rdtgroup initialization
  *

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 8180c539800dcf2b9fe5d6f189fefc7bcb32763b..d512455b4c3a4750de546da909a8dace309b25c9 100644 (file)
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -192,5 +192,6 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,
                            u32 closid, enum resctrl_conf_type type);
+int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d);
 
 #endif /* _RESCTRL_H */