cgroup/cpuset: Miscellaneous code cleanup

Use more descriptive variable names for update_prstate(), remove
unnecessary code and fix some typos. There is no functional change.

Signed-off-by: Waiman Long <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>

Author: Waiman-Long

kernel/cgroup/cpuset.c

@@ -1114,7 +1114,7 @@ enum subparts_cmd {
  * cpus_allowed can be granted or an error code will be returned.
  *
  * For partcmd_disable, the cpuset is being transofrmed from a partition
- * root back to a non-partition root. any CPUs in cpus_allowed that are in
+ * root back to a non-partition root. Any CPUs in cpus_allowed that are in
  * parent's subparts_cpus will be taken away from that cpumask and put back
  * into parent's effective_cpus. 0 should always be returned.
  *
@@ -1225,7 +1225,7 @@ static int update_parent_subparts_cpumask(struct cpuset *cpuset, int cmd,
 		/*
 		 * partcmd_update w/o newmask:
 		 *
-		 * addmask = cpus_allowed & parent->effectiveb_cpus
+		 * addmask = cpus_allowed & parent->effective_cpus
 		 *
 		 * Note that parent's subparts_cpus may have been
 		 * pre-shrunk in case there is a change in the cpu list.
@@ -1365,12 +1365,12 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp)
 			case PRS_DISABLED:
 				/*
 				 * If parent is not a partition root or an
-				 * invalid partition root, clear the state
-				 * state and the CS_CPU_EXCLUSIVE flag.
+				 * invalid partition root, clear its state
+				 * and its CS_CPU_EXCLUSIVE flag.
 				 */
 				WARN_ON_ONCE(cp->partition_root_state
 					     != PRS_ERROR);
-				cp->partition_root_state = 0;
+				cp->partition_root_state = PRS_DISABLED;
 
 				/*
 				 * clear_bit() is an atomic operation and
@@ -1937,30 +1937,28 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 
 /*
  * update_prstate - update partititon_root_state
- * cs:	the cpuset to update
- * val: 0 - disabled, 1 - enabled
+ * cs: the cpuset to update
+ * new_prs: new partition root state
  *
  * Call with cpuset_mutex held.
  */
-static int update_prstate(struct cpuset *cs, int val)
+static int update_prstate(struct cpuset *cs, int new_prs)
 {
 	int err;
 	struct cpuset *parent = parent_cs(cs);
-	struct tmpmasks tmp;
+	struct tmpmasks tmpmask;
 
-	if ((val != 0) && (val != 1))
-		return -EINVAL;
-	if (val == cs->partition_root_state)
+	if (new_prs == cs->partition_root_state)
 		return 0;
 
 	/*
 	 * Cannot force a partial or invalid partition root to a full
 	 * partition root.
 	 */
-	if (val && cs->partition_root_state)
+	if (new_prs && (cs->partition_root_state < 0))
 		return -EINVAL;
 
-	if (alloc_cpumasks(NULL, &tmp))
+	if (alloc_cpumasks(NULL, &tmpmask))
 		return -ENOMEM;
 
 	err = -EINVAL;
@@ -1978,7 +1976,7 @@ static int update_prstate(struct cpuset *cs, int val)
 			goto out;
 
 		err = update_parent_subparts_cpumask(cs, partcmd_enable,
-						     NULL, &tmp);
+						     NULL, &tmpmask);
 		if (err) {
 			update_flag(CS_CPU_EXCLUSIVE, cs, 0);
 			goto out;
@@ -1990,18 +1988,18 @@ static int update_prstate(struct cpuset *cs, int val)
 		 * CS_CPU_EXCLUSIVE bit.
 		 */
 		if (cs->partition_root_state == PRS_ERROR) {
-			cs->partition_root_state = 0;
+			cs->partition_root_state = PRS_DISABLED;
 			update_flag(CS_CPU_EXCLUSIVE, cs, 0);
 			err = 0;
 			goto out;
 		}
 
 		err = update_parent_subparts_cpumask(cs, partcmd_disable,
-						     NULL, &tmp);
+						     NULL, &tmpmask);
 		if (err)
 			goto out;
 
-		cs->partition_root_state = 0;
+		cs->partition_root_state = PRS_DISABLED;
 
 		/* Turning off CS_CPU_EXCLUSIVE will not return error */
 		update_flag(CS_CPU_EXCLUSIVE, cs, 0);
@@ -2015,11 +2013,11 @@ static int update_prstate(struct cpuset *cs, int val)
 		update_tasks_cpumask(parent);
 
 	if (parent->child_ecpus_count)
-		update_sibling_cpumasks(parent, cs, &tmp);
+		update_sibling_cpumasks(parent, cs, &tmpmask);
 
 	rebuild_sched_domains_locked();
 out:
-	free_cpumasks(NULL, &tmp);
+	free_cpumasks(NULL, &tmpmask);
 	return err;
 }
 
@@ -3060,7 +3058,7 @@ static void cpuset_hotplug_update_tasks(struct cpuset *cs, struct tmpmasks *tmp)
 		goto retry;
 	}
 
-	parent =  parent_cs(cs);
+	parent = parent_cs(cs);
 	compute_effective_cpumask(&new_cpus, cs, parent);
 	nodes_and(new_mems, cs->mems_allowed, parent->effective_mems);