[PATCH 1/4] fs/resctrl: Move functions to avoid forward references in subsequent fixes

[Tony Luck <tony.luck@intel.com>]

No functional change. Just pull some functions before rdt_get_tree().

Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 fs/resctrl/rdtgroup.c | 376 +++++++++++++++++++++---------------------
 1 file changed, 188 insertions(+), 188 deletions(-)

diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index 5dfdaa6f9d8f..a6376a3fc4c3 100644
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c
@@ -2782,6 +2782,194 @@ static void schemata_list_destroy(void)
 	}
 }
 
+/*
+ * Move tasks from one to the other group. If @from is NULL, then all tasks
+ * in the systems are moved unconditionally (used for teardown).
+ *
+ * If @mask is not NULL the cpus on which moved tasks are running are set
+ * in that mask so the update smp function call is restricted to affected
+ * cpus.
+ */
+static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
+				 struct cpumask *mask)
+{
+	struct task_struct *p, *t;
+
+	read_lock(&tasklist_lock);
+	for_each_process_thread(p, t) {
+		if (!from || is_closid_match(t, from) ||
+		    is_rmid_match(t, from)) {
+			resctrl_arch_set_closid_rmid(t, to->closid,
+						     to->mon.rmid);
+
+			/*
+			 * Order the closid/rmid stores above before the loads
+			 * in task_curr(). This pairs with the full barrier
+			 * between the rq->curr update and
+			 * resctrl_arch_sched_in() during context switch.
+			 */
+			smp_mb();
+
+			/*
+			 * If the task is on a CPU, set the CPU in the mask.
+			 * The detection is inaccurate as tasks might move or
+			 * schedule before the smp function call takes place.
+			 * In such a case the function call is pointless, but
+			 * there is no other side effect.
+			 */
+			if (IS_ENABLED(CONFIG_SMP) && mask && task_curr(t))
+				cpumask_set_cpu(task_cpu(t), mask);
+		}
+	}
+	read_unlock(&tasklist_lock);
+}
+
+static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
+{
+	struct rdtgroup *sentry, *stmp;
+	struct list_head *head;
+
+	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);
+
+		if (atomic_read(&sentry->waitcount) != 0)
+			sentry->flags = RDT_DELETED;
+		else
+			rdtgroup_remove(sentry);
+	}
+}
+
+/*
+ * Forcibly remove all of subdirectories under root.
+ */
+static void rmdir_all_sub(void)
+{
+	struct rdtgroup *rdtgrp, *tmp;
+
+	/* Move all tasks to the default resource group */
+	rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
+
+	list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
+		/* Free any child rmids */
+		free_all_child_rdtgrp(rdtgrp);
+
+		/* Remove each rdtgroup other than root */
+		if (rdtgrp == &rdtgroup_default)
+			continue;
+
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP ||
+		    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)
+			rdtgroup_pseudo_lock_remove(rdtgrp);
+
+		/*
+		 * Give any CPUs back to the default group. We cannot copy
+		 * cpu_online_mask because a CPU might have executed the
+		 * offline callback already, but is still marked online.
+		 */
+		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);
+		list_del(&rdtgrp->rdtgroup_list);
+
+		if (atomic_read(&rdtgrp->waitcount) != 0)
+			rdtgrp->flags = RDT_DELETED;
+		else
+			rdtgroup_remove(rdtgrp);
+	}
+	/* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */
+	update_closid_rmid(cpu_online_mask, &rdtgroup_default);
+
+	kernfs_remove(kn_info);
+	kernfs_remove(kn_mongrp);
+	kernfs_remove(kn_mondata);
+}
+
+/**
+ * mon_get_kn_priv() - Get the mon_data priv data for this event.
+ *
+ * The same values are used across the mon_data directories of all control and
+ * monitor groups for the same event in the same domain. Keep a list of
+ * allocated structures and re-use an existing one with the same values for
+ * @rid, @domid, etc.
+ *
+ * @rid:    The resource id for the event file being created.
+ * @domid:  The domain id for the event file being created.
+ * @mevt:   The type of event file being created.
+ * @do_sum: Whether SNC summing monitors are being created. Only set
+ *	    when @rid == RDT_RESOURCE_L3.
+ *
+ * Return: Pointer to mon_data private data of the event, NULL on failure.
+ */
+static struct mon_data *mon_get_kn_priv(enum resctrl_res_level rid, int domid,
+					struct mon_evt *mevt,
+					bool do_sum)
+{
+	struct mon_data *priv;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	list_for_each_entry(priv, &mon_data_kn_priv_list, list) {
+		if (priv->rid == rid && priv->domid == domid &&
+		    priv->sum == do_sum && priv->evt == mevt)
+			return priv;
+	}
+
+	priv = kzalloc_obj(*priv);
+	if (!priv)
+		return NULL;
+
+	priv->rid = rid;
+	priv->domid = domid;
+	priv->sum = do_sum;
+	priv->evt = mevt;
+	list_add_tail(&priv->list, &mon_data_kn_priv_list);
+
+	return priv;
+}
+
+/**
+ * mon_put_kn_priv() - Free all allocated mon_data structures.
+ *
+ * Called when resctrl file system is unmounted.
+ */
+static void mon_put_kn_priv(void)
+{
+	struct mon_data *priv, *tmp;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	list_for_each_entry_safe(priv, tmp, &mon_data_kn_priv_list, list) {
+		list_del(&priv->list);
+		kfree(priv);
+	}
+}
+
+static void resctrl_fs_teardown(void)
+{
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	/* Cleared by rdtgroup_destroy_root() */
+	if (!rdtgroup_default.kn)
+		return;
+
+	rmdir_all_sub();
+	rdtgroup_unassign_cntrs(&rdtgroup_default);
+	mon_put_kn_priv();
+	rdt_pseudo_lock_release();
+	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
+	closid_exit();
+	schemata_list_destroy();
+	rdtgroup_destroy_root();
+}
+
 static int rdt_get_tree(struct fs_context *fc)
 {
 	struct rdt_fs_context *ctx = rdt_fc2context(fc);
@@ -2981,194 +3169,6 @@ static int rdt_init_fs_context(struct fs_context *fc)
 	return 0;
 }
 
-/*
- * Move tasks from one to the other group. If @from is NULL, then all tasks
- * in the systems are moved unconditionally (used for teardown).
- *
- * If @mask is not NULL the cpus on which moved tasks are running are set
- * in that mask so the update smp function call is restricted to affected
- * cpus.
- */
-static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
-				 struct cpumask *mask)
-{
-	struct task_struct *p, *t;
-
-	read_lock(&tasklist_lock);
-	for_each_process_thread(p, t) {
-		if (!from || is_closid_match(t, from) ||
-		    is_rmid_match(t, from)) {
-			resctrl_arch_set_closid_rmid(t, to->closid,
-						     to->mon.rmid);
-
-			/*
-			 * Order the closid/rmid stores above before the loads
-			 * in task_curr(). This pairs with the full barrier
-			 * between the rq->curr update and
-			 * resctrl_arch_sched_in() during context switch.
-			 */
-			smp_mb();
-
-			/*
-			 * If the task is on a CPU, set the CPU in the mask.
-			 * The detection is inaccurate as tasks might move or
-			 * schedule before the smp function call takes place.
-			 * In such a case the function call is pointless, but
-			 * there is no other side effect.
-			 */
-			if (IS_ENABLED(CONFIG_SMP) && mask && task_curr(t))
-				cpumask_set_cpu(task_cpu(t), mask);
-		}
-	}
-	read_unlock(&tasklist_lock);
-}
-
-static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
-{
-	struct rdtgroup *sentry, *stmp;
-	struct list_head *head;
-
-	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);
-
-		if (atomic_read(&sentry->waitcount) != 0)
-			sentry->flags = RDT_DELETED;
-		else
-			rdtgroup_remove(sentry);
-	}
-}
-
-/*
- * Forcibly remove all of subdirectories under root.
- */
-static void rmdir_all_sub(void)
-{
-	struct rdtgroup *rdtgrp, *tmp;
-
-	/* Move all tasks to the default resource group */
-	rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
-
-	list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
-		/* Free any child rmids */
-		free_all_child_rdtgrp(rdtgrp);
-
-		/* Remove each rdtgroup other than root */
-		if (rdtgrp == &rdtgroup_default)
-			continue;
-
-		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP ||
-		    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)
-			rdtgroup_pseudo_lock_remove(rdtgrp);
-
-		/*
-		 * Give any CPUs back to the default group. We cannot copy
-		 * cpu_online_mask because a CPU might have executed the
-		 * offline callback already, but is still marked online.
-		 */
-		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);
-		list_del(&rdtgrp->rdtgroup_list);
-
-		if (atomic_read(&rdtgrp->waitcount) != 0)
-			rdtgrp->flags = RDT_DELETED;
-		else
-			rdtgroup_remove(rdtgrp);
-	}
-	/* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */
-	update_closid_rmid(cpu_online_mask, &rdtgroup_default);
-
-	kernfs_remove(kn_info);
-	kernfs_remove(kn_mongrp);
-	kernfs_remove(kn_mondata);
-}
-
-/**
- * mon_get_kn_priv() - Get the mon_data priv data for this event.
- *
- * The same values are used across the mon_data directories of all control and
- * monitor groups for the same event in the same domain. Keep a list of
- * allocated structures and re-use an existing one with the same values for
- * @rid, @domid, etc.
- *
- * @rid:    The resource id for the event file being created.
- * @domid:  The domain id for the event file being created.
- * @mevt:   The type of event file being created.
- * @do_sum: Whether SNC summing monitors are being created. Only set
- *	    when @rid == RDT_RESOURCE_L3.
- *
- * Return: Pointer to mon_data private data of the event, NULL on failure.
- */
-static struct mon_data *mon_get_kn_priv(enum resctrl_res_level rid, int domid,
-					struct mon_evt *mevt,
-					bool do_sum)
-{
-	struct mon_data *priv;
-
-	lockdep_assert_held(&rdtgroup_mutex);
-
-	list_for_each_entry(priv, &mon_data_kn_priv_list, list) {
-		if (priv->rid == rid && priv->domid == domid &&
-		    priv->sum == do_sum && priv->evt == mevt)
-			return priv;
-	}
-
-	priv = kzalloc_obj(*priv);
-	if (!priv)
-		return NULL;
-
-	priv->rid = rid;
-	priv->domid = domid;
-	priv->sum = do_sum;
-	priv->evt = mevt;
-	list_add_tail(&priv->list, &mon_data_kn_priv_list);
-
-	return priv;
-}
-
-/**
- * mon_put_kn_priv() - Free all allocated mon_data structures.
- *
- * Called when resctrl file system is unmounted.
- */
-static void mon_put_kn_priv(void)
-{
-	struct mon_data *priv, *tmp;
-
-	lockdep_assert_held(&rdtgroup_mutex);
-
-	list_for_each_entry_safe(priv, tmp, &mon_data_kn_priv_list, list) {
-		list_del(&priv->list);
-		kfree(priv);
-	}
-}
-
-static void resctrl_fs_teardown(void)
-{
-	lockdep_assert_held(&rdtgroup_mutex);
-
-	/* Cleared by rdtgroup_destroy_root() */
-	if (!rdtgroup_default.kn)
-		return;
-
-	rmdir_all_sub();
-	rdtgroup_unassign_cntrs(&rdtgroup_default);
-	mon_put_kn_priv();
-	rdt_pseudo_lock_release();
-	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
-	closid_exit();
-	schemata_list_destroy();
-	rdtgroup_destroy_root();
-}
-
 static void rdt_kill_sb(struct super_block *sb)
 {
 	struct rdt_resource *r;
-- 
2.54.0