cpusets: decrustify cpuset mask update code

[platform/adaptation/renesas_rcar/renesas_kernel.git] / kernel / cpuset.c

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 203ca52..64ad59c 100644 (file)
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -488,6 +488,14 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial)
                        return -EINVAL;
        }
 
+       /* Cpusets with tasks can't have empty cpus_allowed or mems_allowed */
+       if (cgroup_task_count(cur->css.cgroup)) {
+               if (cpus_empty(trial->cpus_allowed) ||
+                   nodes_empty(trial->mems_allowed)) {
+                       return -ENOSPC;
+               }
+       }
+
        return 0;
 }
 
@@ -710,11 +718,13 @@ static int update_cpumask(struct cpuset *cs, char *buf)
        trialcs = *cs;
 
        /*
-        * We allow a cpuset's cpus_allowed to be empty; if it has attached
-        * tasks, we'll catch it later when we validate the change and return
-        * -ENOSPC.
+        * An empty cpus_allowed is ok iff there are no tasks in the cpuset.
+        * Since cpulist_parse() fails on an empty mask, we special case
+        * that parsing.  The validate_change() call ensures that cpusets
+        * with tasks have cpus.
         */
-       if (!buf[0] || (buf[0] == '\n' && !buf[1])) {
+       buf = strstrip(buf);
+       if (!*buf) {
                cpus_clear(trialcs.cpus_allowed);
        } else {
                retval = cpulist_parse(buf, trialcs.cpus_allowed);
@@ -722,10 +732,6 @@ static int update_cpumask(struct cpuset *cs, char *buf)
                        return retval;
        }
        cpus_and(trialcs.cpus_allowed, trialcs.cpus_allowed, cpu_online_map);
-       /* cpus_allowed cannot be empty for a cpuset with attached tasks. */
-       if (cgroup_task_count(cs->css.cgroup) &&
-           cpus_empty(trialcs.cpus_allowed))
-               return -ENOSPC;
        retval = validate_change(cs, &trialcs);
        if (retval < 0)
                return retval;
@@ -830,29 +836,19 @@ static int update_nodemask(struct cpuset *cs, char *buf)
        trialcs = *cs;
 
        /*
-        * We allow a cpuset's mems_allowed to be empty; if it has attached
-        * tasks, we'll catch it later when we validate the change and return
-        * -ENOSPC.
+        * An empty mems_allowed is ok iff there are no tasks in the cpuset.
+        * Since nodelist_parse() fails on an empty mask, we special case
+        * that parsing.  The validate_change() call ensures that cpusets
+        * with tasks have memory.
         */
-       if (!buf[0] || (buf[0] == '\n' && !buf[1])) {
+       buf = strstrip(buf);
+       if (!*buf) {
                nodes_clear(trialcs.mems_allowed);
        } else {
                retval = nodelist_parse(buf, trialcs.mems_allowed);
                if (retval < 0)
                        goto done;
-               if (!nodes_intersects(trialcs.mems_allowed,
-                                               node_states[N_HIGH_MEMORY])) {
-                       /*
-                        * error if only memoryless nodes specified.
-                        */
-                       retval = -ENOSPC;
-                       goto done;
-               }
        }
-       /*
-        * Exclude memoryless nodes.  We know that trialcs.mems_allowed
-        * contains at least one node with memory.
-        */
        nodes_and(trialcs.mems_allowed, trialcs.mems_allowed,
                                                node_states[N_HIGH_MEMORY]);
        oldmem = cs->mems_allowed;
@@ -860,12 +856,6 @@ static int update_nodemask(struct cpuset *cs, char *buf)
                retval = 0;             /* Too easy - nothing to do */
                goto done;
        }
-       /* mems_allowed cannot be empty for a cpuset with attached tasks. */
-       if (cgroup_task_count(cs->css.cgroup) &&
-           nodes_empty(trialcs.mems_allowed)) {
-               retval = -ENOSPC;
-               goto done;
-       }
        retval = validate_change(cs, &trialcs);
        if (retval < 0)
                goto done;