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Diffstat (limited to 'kernel/cpuset.c')
-rw-r--r--kernel/cpuset.c50
1 files changed, 20 insertions, 30 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 203ca52e78d..64ad59cfad9 100644
--- 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;