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sched: put back some stack hog changes that were undone in kernel/sched.c

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Impact: prevents panic from stack overflow on numa-capable machines.

Some of the "removal of stack hogs" changes in kernel/sched.c by using
node_to_cpumask_ptr were undone by the early cpumask API updates, and
causes a panic due to stack overflow.  This patch undoes those changes
by using cpumask_of_node() which returns a 'const struct cpumask *'.

In addition, cpu_coregoup_map is replaced with cpu_coregroup_mask further
reducing stack usage.  (Both of these updates removed 9 FIXME's!)

Also:
   Pick up some remaining changes from the old 'cpumask_t' functions to
   the new 'struct cpumask *' functions.

   Optimize memory traffic by allocating each percpu local_cpu_mask on the
   same node as the referring cpu.

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Mike Travis 2008-12-31 18:08:45 -08:00 committed by Ingo Molnar
parent 730cf27246
commit 6ca09dfc9f
2 changed files with 17 additions and 39 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

53
kernel/sched.c
View file

@ -3715,7 +3715,7 @@ redo:
* don't kick the migration_thread, if the curr
* task on busiest cpu can't be moved to this_cpu
*/
if (!cpu_isset(this_cpu, busiest->curr->cpus_allowed)) {
if (!cpumask_test_cpu(this_cpu, &busiest->curr->cpus_allowed)) {
double_unlock_balance(this_rq, busiest);
all_pinned = 1;
return ld_moved;
@ -6220,9 +6220,7 @@ static int __migrate_task_irq(struct task_struct *p, int src_cpu, int dest_cpu)
static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
{
int dest_cpu;
/* FIXME: Use cpumask_of_node here. */
cpumask_t _nodemask = node_to_cpumask(cpu_to_node(dead_cpu));
const struct cpumask *nodemask = &_nodemask;
const struct cpumask *nodemask = cpumask_of_node(cpu_to_node(dead_cpu));
again:
/* Look for allowed, online CPU in same node. */
@ -7133,21 +7131,18 @@ static int find_next_best_node(int node, nodemask_t *used_nodes)
static void sched_domain_node_span(int node, struct cpumask *span)
{
nodemask_t used_nodes;
/* FIXME: use cpumask_of_node() */
node_to_cpumask_ptr(nodemask, node);
int i;
cpus_clear(*span);
cpumask_clear(span);
nodes_clear(used_nodes);
cpus_or(*span, *span, *nodemask);
cpumask_or(span, span, cpumask_of_node(node));
node_set(node, used_nodes);
for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
int next_node = find_next_best_node(node, &used_nodes);
node_to_cpumask_ptr_next(nodemask, next_node);
cpus_or(*span, *span, *nodemask);
cpumask_or(span, span, cpumask_of_node(next_node));
}
}
#endif /* CONFIG_NUMA */
@ -7227,9 +7222,7 @@ cpu_to_phys_group(int cpu, const struct cpumask *cpu_map,
{
int group;
#ifdef CONFIG_SCHED_MC
/* FIXME: Use cpu_coregroup_mask. */
*mask = cpu_coregroup_map(cpu);
cpus_and(*mask, *mask, *cpu_map);
cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map);
group = cpumask_first(mask);
#elif defined(CONFIG_SCHED_SMT)
cpumask_and(mask, &per_cpu(cpu_sibling_map, cpu), cpu_map);
@ -7259,10 +7252,8 @@ static int cpu_to_allnodes_group(int cpu, const struct cpumask *cpu_map,
struct cpumask *nodemask)
{
int group;
/* FIXME: use cpumask_of_node */
node_to_cpumask_ptr(pnodemask, cpu_to_node(cpu));
cpumask_and(nodemask, pnodemask, cpu_map);
cpumask_and(nodemask, cpumask_of_node(cpu_to_node(cpu)), cpu_map);
group = cpumask_first(nodemask);
if (sg)
@ -7313,10 +7304,8 @@ static void free_sched_groups(const struct cpumask *cpu_map,
for (i = 0; i < nr_node_ids; i++) {
struct sched_group *oldsg, *sg = sched_group_nodes[i];
/* FIXME: Use cpumask_of_node */
node_to_cpumask_ptr(pnodemask, i);
cpus_and(*nodemask, *pnodemask, *cpu_map);
cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
if (cpumask_empty(nodemask))
continue;
@ -7525,9 +7514,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
for_each_cpu(i, cpu_map) {
struct sched_domain *sd = NULL, *p;
/* FIXME: use cpumask_of_node */
*nodemask = node_to_cpumask(cpu_to_node(i));
cpus_and(*nodemask, *nodemask, *cpu_map);
cpumask_and(nodemask, cpumask_of_node(cpu_to_node(i)), cpu_map);
#ifdef CONFIG_NUMA
if (cpumask_weight(cpu_map) >
@ -7568,9 +7555,8 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
sd = &per_cpu(core_domains, i).sd;
SD_INIT(sd, MC);
set_domain_attribute(sd, attr);
*sched_domain_span(sd) = cpu_coregroup_map(i);
cpumask_and(sched_domain_span(sd),
sched_domain_span(sd), cpu_map);
cpumask_and(sched_domain_span(sd), cpu_map,
cpu_coregroup_mask(i));
sd->parent = p;
p->child = sd;
cpu_to_core_group(i, cpu_map, &sd->groups, tmpmask);
@ -7606,9 +7592,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
#ifdef CONFIG_SCHED_MC
/* Set up multi-core groups */
for_each_cpu(i, cpu_map) {
/* FIXME: Use cpu_coregroup_mask */
*this_core_map = cpu_coregroup_map(i);
cpus_and(*this_core_map, *this_core_map, *cpu_map);
cpumask_and(this_core_map, cpu_coregroup_mask(i), cpu_map);
if (i != cpumask_first(this_core_map))
continue;
@ -7620,9 +7604,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
/* Set up physical groups */
for (i = 0; i < nr_node_ids; i++) {
/* FIXME: Use cpumask_of_node */
*nodemask = node_to_cpumask(i);
cpus_and(*nodemask, *nodemask, *cpu_map);
cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
if (cpumask_empty(nodemask))
continue;
@ -7644,11 +7626,8 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
struct sched_group *sg, *prev;
int j;
/* FIXME: Use cpumask_of_node */
*nodemask = node_to_cpumask(i);
cpumask_clear(covered);
cpus_and(*nodemask, *nodemask, *cpu_map);
cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
if (cpumask_empty(nodemask)) {
sched_group_nodes[i] = NULL;
continue;
@ -7679,8 +7658,6 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
for (j = 0; j < nr_node_ids; j++) {
int n = (i + j) % nr_node_ids;
/* FIXME: Use cpumask_of_node */
node_to_cpumask_ptr(pnodemask, n);
cpumask_complement(notcovered, covered);
cpumask_and(tmpmask, notcovered, cpu_map);
@ -7688,7 +7665,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
if (cpumask_empty(tmpmask))
break;
cpumask_and(tmpmask, tmpmask, pnodemask);
cpumask_and(tmpmask, tmpmask, cpumask_of_node(n));
if (cpumask_empty(tmpmask))
continue;

3
kernel/sched_rt.c
View file

@ -1383,7 +1383,8 @@ static inline void init_sched_rt_class(void)
unsigned int i;
for_each_possible_cpu(i)
alloc_cpumask_var(&per_cpu(local_cpu_mask, i), GFP_KERNEL);
alloc_cpumask_var_node(&per_cpu(local_cpu_mask, i),
GFP_KERNEL, cpu_to_node(i));
}
#endif /* CONFIG_SMP */