sched/numa: Call task_numa_free() from do_execve()
It is possible for a task in a numa group to call exec, and
have the new (unrelated) executable inherit the numa group
association from its former self.
This has the potential to break numa grouping, and is trivial
to fix.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-51-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/fs/exec.c b/fs/exec.c
index 8875dd1..2ea437e 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1547,6 +1547,7 @@
current->fs->in_exec = 0;
current->in_execve = 0;
acct_update_integrals(current);
+ task_numa_free(current);
free_bprm(bprm);
if (displaced)
put_files_struct(displaced);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7244822..f638510 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1458,6 +1458,7 @@
extern void task_numa_fault(int last_node, int node, int pages, int flags);
extern pid_t task_numa_group_id(struct task_struct *p);
extern void set_numabalancing_state(bool enabled);
+extern void task_numa_free(struct task_struct *p);
#else
static inline void task_numa_fault(int last_node, int node, int pages,
int flags)
@@ -1470,6 +1471,9 @@
static inline void set_numabalancing_state(bool enabled)
{
}
+static inline void task_numa_free(struct task_struct *p)
+{
+}
#endif
static inline struct pid *task_pid(struct task_struct *task)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 4c40e13..c4df2de 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1418,6 +1418,7 @@
{
struct numa_group *grp = p->numa_group;
int i;
+ void *numa_faults = p->numa_faults;
if (grp) {
for (i = 0; i < 2*nr_node_ids; i++)
@@ -1433,7 +1434,9 @@
put_numa_group(grp);
}
- kfree(p->numa_faults);
+ p->numa_faults = NULL;
+ p->numa_faults_buffer = NULL;
+ kfree(numa_faults);
}
/*
@@ -1452,6 +1455,10 @@
if (!p->mm)
return;
+ /* Do not worry about placement if exiting */
+ if (p->state == TASK_DEAD)
+ return;
+
/* Allocate buffer to track faults on a per-node basis */
if (unlikely(!p->numa_faults)) {
int size = sizeof(*p->numa_faults) * 2 * nr_node_ids;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 8037b10..eeb1923 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -559,11 +559,6 @@
#ifdef CONFIG_NUMA_BALANCING
extern int migrate_task_to(struct task_struct *p, int cpu);
extern int migrate_swap(struct task_struct *, struct task_struct *);
-extern void task_numa_free(struct task_struct *p);
-#else /* CONFIG_NUMA_BALANCING */
-static inline void task_numa_free(struct task_struct *p)
-{
-}
#endif /* CONFIG_NUMA_BALANCING */
#ifdef CONFIG_SMP
