Commit f9a86fcb authored by Mike Travis's avatar Mike Travis Committed by Ingo Molnar
Browse files

cpuset: modify cpuset_set_cpus_allowed to use cpumask pointer 



  * Modify cpuset_cpus_allowed to return the currently allowed cpuset
    via a pointer argument instead of as the function return value.

  * Use new set_cpus_allowed_ptr function.

  * Cleanup CPU_MASK_ALL and NODE_MASK_ALL uses.

Depends on:
	[sched-devel]: sched: add new set_cpus_allowed_ptr function

Signed-off-by: default avatarMike Travis <travis@sgi.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent f70316da

include/linux/cpuset.h

+7 −6
Original line number Diff line number Diff line
@@ -20,8 +20,8 @@ extern int number_of_cpusets; /* How many cpusets are defined in system? */ 
extern int cpuset_init_early(void);

extern int cpuset_init(void);

extern void cpuset_init_smp(void);

extern cpumask_t cpuset_cpus_allowed(struct task_struct *p);

extern cpumask_t cpuset_cpus_allowed_locked(struct task_struct *p);

extern void cpuset_cpus_allowed(struct task_struct *p, cpumask_t *mask);

extern void cpuset_cpus_allowed_locked(struct task_struct *p, cpumask_t *mask);

extern nodemask_t cpuset_mems_allowed(struct task_struct *p);

#define cpuset_current_mems_allowed (current->mems_allowed)

void cpuset_init_current_mems_allowed(void);
@@ -84,13 +84,14 @@ static inline int cpuset_init_early(void) { return 0; } 
static inline int cpuset_init(void) { return 0; }

static inline void cpuset_init_smp(void) {}



static inline cpumask_t cpuset_cpus_allowed(struct task_struct *p)

static inline void cpuset_cpus_allowed(struct task_struct *p, cpumask_t *mask)

{

	return cpu_possible_map;

	*mask = cpu_possible_map;

}

static inline cpumask_t cpuset_cpus_allowed_locked(struct task_struct *p)

static inline void cpuset_cpus_allowed_locked(struct task_struct *p,

								cpumask_t *mask)

{

	return cpu_possible_map;

	*mask = cpu_possible_map;

}



static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)

kernel/cpuset.c

+12 −19
Original line number Diff line number Diff line
@@ -729,7 +729,7 @@ int cpuset_test_cpumask(struct task_struct *tsk, struct cgroup_scanner *scan) 
 */

void cpuset_change_cpumask(struct task_struct *tsk, struct cgroup_scanner *scan)

{

	set_cpus_allowed(tsk, (cgroup_cs(scan->cg))->cpus_allowed);

	set_cpus_allowed_ptr(tsk, &((cgroup_cs(scan->cg))->cpus_allowed));

}



/**
@@ -1178,7 +1178,7 @@ static void cpuset_attach(struct cgroup_subsys *ss, 


	mutex_lock(&callback_mutex);

	guarantee_online_cpus(cs, &cpus);

	set_cpus_allowed(tsk, cpus);

	set_cpus_allowed_ptr(tsk, &cpus);

	mutex_unlock(&callback_mutex);



	from = oldcs->mems_allowed;
@@ -1555,8 +1555,8 @@ static struct cgroup_subsys_state *cpuset_create( 
	if (is_spread_slab(parent))

		set_bit(CS_SPREAD_SLAB, &cs->flags);

	set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);

	cs->cpus_allowed = CPU_MASK_NONE;

	cs->mems_allowed = NODE_MASK_NONE;

	cpus_clear(cs->cpus_allowed);

	nodes_clear(cs->mems_allowed);

	cs->mems_generation = cpuset_mems_generation++;

	fmeter_init(&cs->fmeter);
@@ -1625,8 +1625,8 @@ int __init cpuset_init(void) 
{

	int err = 0;



	top_cpuset.cpus_allowed = CPU_MASK_ALL;

	top_cpuset.mems_allowed = NODE_MASK_ALL;

	cpus_setall(top_cpuset.cpus_allowed);

	nodes_setall(top_cpuset.mems_allowed);



	fmeter_init(&top_cpuset.fmeter);

	top_cpuset.mems_generation = cpuset_mems_generation++;
@@ -1844,6 +1844,7 @@ void __init cpuset_init_smp(void) 


 * cpuset_cpus_allowed - return cpus_allowed mask from a tasks cpuset.

 * @tsk: pointer to task_struct from which to obtain cpuset->cpus_allowed.

 * @pmask: pointer to cpumask_t variable to receive cpus_allowed set.

 *

 * Description: Returns the cpumask_t cpus_allowed of the cpuset

 * attached to the specified @tsk.  Guaranteed to return some non-empty
@@ -1851,35 +1852,27 @@ void __init cpuset_init_smp(void) 
 * tasks cpuset.

 **/



cpumask_t cpuset_cpus_allowed(struct task_struct *tsk)

void cpuset_cpus_allowed(struct task_struct *tsk, cpumask_t *pmask)

{

	cpumask_t mask;



	mutex_lock(&callback_mutex);

	mask = cpuset_cpus_allowed_locked(tsk);

	cpuset_cpus_allowed_locked(tsk, pmask);

	mutex_unlock(&callback_mutex);



	return mask;

}



/**

 * cpuset_cpus_allowed_locked - return cpus_allowed mask from a tasks cpuset.

 * Must be called with callback_mutex held.

 **/

cpumask_t cpuset_cpus_allowed_locked(struct task_struct *tsk)

void cpuset_cpus_allowed_locked(struct task_struct *tsk, cpumask_t *pmask)

{

	cpumask_t mask;



	task_lock(tsk);

	guarantee_online_cpus(task_cs(tsk), &mask);

	guarantee_online_cpus(task_cs(tsk), pmask);

	task_unlock(tsk);



	return mask;

}



void cpuset_init_current_mems_allowed(void)

{

	current->mems_allowed = NODE_MASK_ALL;

	nodes_setall(current->mems_allowed);

}



/**

kernel/sched.c

+5 −3
Original line number Diff line number Diff line
@@ -4941,13 +4941,13 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask) 
	if (retval)

		goto out_unlock;



	cpus_allowed = cpuset_cpus_allowed(p);

	cpuset_cpus_allowed(p, &cpus_allowed);

	cpus_and(new_mask, new_mask, cpus_allowed);

 again:

	retval = set_cpus_allowed(p, new_mask);



	if (!retval) {

		cpus_allowed = cpuset_cpus_allowed(p);

		cpuset_cpus_allowed(p, &cpus_allowed);

		if (!cpus_subset(new_mask, cpus_allowed)) {

			/*

			 * We must have raced with a concurrent cpuset
@@ -5661,7 +5661,9 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p) 


		/* No more Mr. Nice Guy. */

		if (dest_cpu >= nr_cpu_ids) {

			cpumask_t cpus_allowed = cpuset_cpus_allowed_locked(p);

			cpumask_t cpus_allowed;



			cpuset_cpus_allowed_locked(p, &cpus_allowed);

			/*

			 * Try to stay on the same cpuset, where the

			 * current cpuset may be a subset of all cpus.

mm/pdflush.c

+2 −2
Original line number Diff line number Diff line
@@ -187,8 +187,8 @@ static int pdflush(void *dummy) 
	 * This is needed as pdflush's are dynamically created and destroyed.

	 * The boottime pdflush's are easily placed w/o these 2 lines.

	 */

	cpus_allowed = cpuset_cpus_allowed(current);

	set_cpus_allowed(current, cpus_allowed);

	cpuset_cpus_allowed(current, &cpus_allowed);

	set_cpus_allowed_ptr(current, &cpus_allowed);



	return __pdflush(&my_work);

}

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