Commit 82727018 authored by Rik van Riel's avatar Rik van Riel Committed by Ingo Molnar
Browse files

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: default avatarRik van Riel <riel@redhat.com>
Signed-off-by: default avatarMel 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: default avatarPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-51-git-send-email-mgorman@suse.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 83e1d2cd

fs/exec.c

+1 −0
Original line number Diff line number Diff line
@@ -1547,6 +1547,7 @@ static int do_execve_common(const char *filename, 
	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);

include/linux/sched.h

+4 −0
Original line number Diff line number Diff line
@@ -1458,6 +1458,7 @@ struct task_struct { 
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 pid_t task_numa_group_id(struct task_struct *p) 
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)

kernel/sched/fair.c

+8 −1
Original line number Diff line number Diff line
@@ -1418,6 +1418,7 @@ void task_numa_free(struct task_struct *p) 
{

	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 @@ void task_numa_free(struct task_struct *p) 
		put_numa_group(grp);

	}



	kfree(p->numa_faults);

	p->numa_faults = NULL;

	p->numa_faults_buffer = NULL;

	kfree(numa_faults);

}



/*
@@ -1452,6 +1455,10 @@ void task_numa_fault(int last_cpupid, int node, int pages, int flags) 
	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;

kernel/sched/sched.h

+0 −5
Original line number Diff line number Diff line
@@ -559,11 +559,6 @@ static inline u64 rq_clock_task(struct rq *rq) 
#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

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