The patch titled
cpuset: alloc nodemask_t on the heap rather than the stack
has been added to the -mm tree. Its filename is
cpuset-alloc-nodemask_t-on-the-heap-rather-than-the-stack.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: cpuset: alloc nodemask_t on the heap rather than the stack
From: Miao Xie <miaox@xxxxxxxxxxxxxx>
Signed-off-by: Miao Xie <miaox@xxxxxxxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Nick Piggin <npiggin@xxxxxxx>
Cc: Paul Menage <menage@xxxxxxxxxx>
Cc: Li Zefan <lizf@xxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/cpuset.c | 94 ++++++++++++++++++++++++++++++++--------------
1 file changed, 66 insertions(+), 28 deletions(-)
diff -puN kernel/cpuset.c~cpuset-alloc-nodemask_t-on-the-heap-rather-than-the-stack kernel/cpuset.c
--- a/kernel/cpuset.c~cpuset-alloc-nodemask_t-on-the-heap-rather-than-the-stack
+++ a/kernel/cpuset.c
@@ -970,15 +970,20 @@ static void cpuset_change_nodemask(struc
struct cpuset *cs;
int migrate;
const nodemask_t *oldmem = scan->data;
- nodemask_t newmems;
+ NODEMASK_ALLOC(nodemask_t, newmems, GFP_KERNEL);
+
+ if (!newmems)
+ return;
cs = cgroup_cs(scan->cg);
- guarantee_online_mems(cs, &newmems);
+ guarantee_online_mems(cs, newmems);
task_lock(p);
- cpuset_change_task_nodemask(p, &newmems);
+ cpuset_change_task_nodemask(p, newmems);
task_unlock(p);
+ NODEMASK_FREE(newmems);
+
mm = get_task_mm(p);
if (!mm)
return;
@@ -1048,16 +1053,21 @@ static void update_tasks_nodemask(struct
static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
const char *buf)
{
- nodemask_t oldmem;
+ NODEMASK_ALLOC(nodemask_t, oldmem, GFP_KERNEL);
int retval;
struct ptr_heap heap;
+ if (!oldmem)
+ return -ENOMEM;
+
/*
* top_cpuset.mems_allowed tracks node_stats[N_HIGH_MEMORY];
* it's read-only
*/
- if (cs == &top_cpuset)
- return -EACCES;
+ if (cs == &top_cpuset) {
+ retval = -EACCES;
+ goto done;
+ }
/*
* An empty mems_allowed is ok iff there are no tasks in the cpuset.
@@ -1073,11 +1083,13 @@ static int update_nodemask(struct cpuset
goto done;
if (!nodes_subset(trialcs->mems_allowed,
- node_states[N_HIGH_MEMORY]))
- return -EINVAL;
+ node_states[N_HIGH_MEMORY])) {
+ retval = -EINVAL;
+ goto done;
+ }
}
- oldmem = cs->mems_allowed;
- if (nodes_equal(oldmem, trialcs->mems_allowed)) {
+ *oldmem = cs->mems_allowed;
+ if (nodes_equal(*oldmem, trialcs->mems_allowed)) {
retval = 0; /* Too easy - nothing to do */
goto done;
}
@@ -1093,10 +1105,11 @@ static int update_nodemask(struct cpuset
cs->mems_allowed = trialcs->mems_allowed;
mutex_unlock(&callback_mutex);
- update_tasks_nodemask(cs, &oldmem, &heap);
+ update_tasks_nodemask(cs, oldmem, &heap);
heap_free(&heap);
done:
+ NODEMASK_FREE(oldmem);
return retval;
}
@@ -1381,39 +1394,47 @@ static void cpuset_attach(struct cgroup_
struct cgroup *oldcont, struct task_struct *tsk,
bool threadgroup)
{
- nodemask_t from, to;
struct mm_struct *mm;
struct cpuset *cs = cgroup_cs(cont);
struct cpuset *oldcs = cgroup_cs(oldcont);
+ NODEMASK_ALLOC(nodemask_t, from, GFP_KERNEL);
+ NODEMASK_ALLOC(nodemask_t, to, GFP_KERNEL);
+
+ if (from == NULL || to == NULL)
+ goto alloc_fail;
if (cs == &top_cpuset) {
cpumask_copy(cpus_attach, cpu_possible_mask);
} else {
guarantee_online_cpus(cs, cpus_attach);
}
- guarantee_online_mems(cs, &to);
+ guarantee_online_mems(cs, to);
/* do per-task migration stuff possibly for each in the threadgroup */
- cpuset_attach_task(tsk, &to, cs);
+ cpuset_attach_task(tsk, to, cs);
if (threadgroup) {
struct task_struct *c;
rcu_read_lock();
list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) {
- cpuset_attach_task(c, &to, cs);
+ cpuset_attach_task(c, to, cs);
}
rcu_read_unlock();
}
/* change mm; only needs to be done once even if threadgroup */
- from = oldcs->mems_allowed;
- to = cs->mems_allowed;
+ *from = oldcs->mems_allowed;
+ *to = cs->mems_allowed;
mm = get_task_mm(tsk);
if (mm) {
- mpol_rebind_mm(mm, &to);
+ mpol_rebind_mm(mm, to);
if (is_memory_migrate(cs))
- cpuset_migrate_mm(mm, &from, &to);
+ cpuset_migrate_mm(mm, from, to);
mmput(mm);
}
+
+alloc_fail:
+ NODEMASK_FREE(from);
+ NODEMASK_FREE(to);
}
/* The various types of files and directories in a cpuset file system */
@@ -1558,13 +1579,21 @@ static int cpuset_sprintf_cpulist(char *
static int cpuset_sprintf_memlist(char *page, struct cpuset *cs)
{
- nodemask_t mask;
+ NODEMASK_ALLOC(nodemask_t, mask, GFP_KERNEL);
+ int retval;
+
+ if (mask == NULL)
+ return -ENOMEM;
mutex_lock(&callback_mutex);
- mask = cs->mems_allowed;
+ *mask = cs->mems_allowed;
mutex_unlock(&callback_mutex);
- return nodelist_scnprintf(page, PAGE_SIZE, mask);
+ retval = nodelist_scnprintf(page, PAGE_SIZE, *mask);
+
+ NODEMASK_FREE(mask);
+
+ return retval;
}
static ssize_t cpuset_common_file_read(struct cgroup *cont,
@@ -1993,7 +2022,10 @@ static void scan_for_empty_cpusets(struc
struct cpuset *cp; /* scans cpusets being updated */
struct cpuset *child; /* scans child cpusets of cp */
struct cgroup *cont;
- nodemask_t oldmems;
+ NODEMASK_ALLOC(nodemask_t, oldmems, GFP_KERNEL);
+
+ if (oldmems == NULL)
+ return;
list_add_tail((struct list_head *)&root->stack_list, &queue);
@@ -2010,7 +2042,7 @@ static void scan_for_empty_cpusets(struc
nodes_subset(cp->mems_allowed, node_states[N_HIGH_MEMORY]))
continue;
- oldmems = cp->mems_allowed;
+ *oldmems = cp->mems_allowed;
/* Remove offline cpus and mems from this cpuset. */
mutex_lock(&callback_mutex);
@@ -2026,9 +2058,10 @@ static void scan_for_empty_cpusets(struc
remove_tasks_in_empty_cpuset(cp);
else {
update_tasks_cpumask(cp, NULL);
- update_tasks_nodemask(cp, &oldmems, NULL);
+ update_tasks_nodemask(cp, oldmems, NULL);
}
}
+ NODEMASK_FREE(oldmems);
}
/*
@@ -2086,16 +2119,19 @@ static int cpuset_track_online_cpus(stru
static int cpuset_track_online_nodes(struct notifier_block *self,
unsigned long action, void *arg)
{
- nodemask_t oldmems;
+ NODEMASK_ALLOC(nodemask_t, oldmems, GFP_KERNEL);
+
+ if (oldmems == NULL)
+ return NOTIFY_DONE;
cgroup_lock();
switch (action) {
case MEM_ONLINE:
- oldmems = top_cpuset.mems_allowed;
+ *oldmems = top_cpuset.mems_allowed;
mutex_lock(&callback_mutex);
top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
mutex_unlock(&callback_mutex);
- update_tasks_nodemask(&top_cpuset, &oldmems, NULL);
+ update_tasks_nodemask(&top_cpuset, oldmems, NULL);
break;
case MEM_OFFLINE:
/*
@@ -2108,6 +2144,8 @@ static int cpuset_track_online_nodes(str
break;
}
cgroup_unlock();
+
+ NODEMASK_FREE(oldmems);
return NOTIFY_OK;
}
#endif
_
Patches currently in -mm which might be from miaox@xxxxxxxxxxxxxx are
origin.patch
cpuset-fix-the-problem-that-cpuset_mem_spread_node-returns-an-offline-node.patch
cpuset-alloc-nodemask_t-on-the-heap-rather-than-the-stack.patch
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