Skip to content

Commit

Permalink
[PATCH] sched: remove unnecessary sched group allocations
Browse files Browse the repository at this point in the history 
Remove dynamic sched group allocations for MC and SMP domains.  These
allocations can easily fail on big systems(1024 or so CPUs) and we can live
with out these dynamic allocations.

[akpm@osdl.org: build fix]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
  • Loading branch information
Siddha, Suresh B authored and Linus Torvalds committed Oct 3, 2006
1 parent 5c1e176 commit a616058
Showing 1 changed file with 38 additions and 66 deletions.
104 changes: 38 additions & 66 deletions kernel/sched.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5489,15 +5489,17 @@ __setup ("isolcpus=", isolated_cpu_setup);
* covered by the given span, and will set each group's ->cpumask correctly,
* and ->cpu_power to 0.
*/
static void init_sched_build_groups(struct sched_group groups[], cpumask_t span,
int (*group_fn)(int cpu))
static void
init_sched_build_groups(struct sched_group groups[], cpumask_t span,
const cpumask_t *cpu_map,
int (*group_fn)(int cpu, const cpumask_t *cpu_map))
{
struct sched_group *first = NULL, *last = NULL;
cpumask_t covered = CPU_MASK_NONE;
int i;

for_each_cpu_mask(i, span) {
int group = group_fn(i);
int group = group_fn(i, cpu_map);
struct sched_group *sg = &groups[group];
int j;

Expand All @@ -5508,7 +5510,7 @@ static void init_sched_build_groups(struct sched_group groups[], cpumask_t span,
sg->cpu_power = 0;

for_each_cpu_mask(j, span) {
if (group_fn(j) != group)
if (group_fn(j, cpu_map) != group)
continue;

cpu_set(j, covered);
Expand Down Expand Up @@ -6084,7 +6086,7 @@ int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
static DEFINE_PER_CPU(struct sched_domain, cpu_domains);
static struct sched_group sched_group_cpus[NR_CPUS];

static int cpu_to_cpu_group(int cpu)
static int cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map)
{
return cpu;
}
Expand All @@ -6095,31 +6097,36 @@ static int cpu_to_cpu_group(int cpu)
*/
#ifdef CONFIG_SCHED_MC
static DEFINE_PER_CPU(struct sched_domain, core_domains);
static struct sched_group *sched_group_core_bycpu[NR_CPUS];
static struct sched_group sched_group_core[NR_CPUS];
#endif

#if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT)
static int cpu_to_core_group(int cpu)
static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map)
{
return first_cpu(cpu_sibling_map[cpu]);
cpumask_t mask = cpu_sibling_map[cpu];
cpus_and(mask, mask, *cpu_map);
return first_cpu(mask);
}
#elif defined(CONFIG_SCHED_MC)
static int cpu_to_core_group(int cpu)
static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map)
{
return cpu;
}
#endif

static DEFINE_PER_CPU(struct sched_domain, phys_domains);
static struct sched_group *sched_group_phys_bycpu[NR_CPUS];
static struct sched_group sched_group_phys[NR_CPUS];

static int cpu_to_phys_group(int cpu)
static int cpu_to_phys_group(int cpu, const cpumask_t *cpu_map)
{
#ifdef CONFIG_SCHED_MC
cpumask_t mask = cpu_coregroup_map(cpu);
cpus_and(mask, mask, *cpu_map);
return first_cpu(mask);
#elif defined(CONFIG_SCHED_SMT)
return first_cpu(cpu_sibling_map[cpu]);
cpumask_t mask = cpu_sibling_map[cpu];
cpus_and(mask, mask, *cpu_map);
return first_cpu(mask);
#else
return cpu;
#endif
Expand All @@ -6137,7 +6144,7 @@ static struct sched_group **sched_group_nodes_bycpu[NR_CPUS];
static DEFINE_PER_CPU(struct sched_domain, allnodes_domains);
static struct sched_group *sched_group_allnodes_bycpu[NR_CPUS];

static int cpu_to_allnodes_group(int cpu)
static int cpu_to_allnodes_group(int cpu, const cpumask_t *cpu_map)
{
return cpu_to_node(cpu);
}
Expand Down Expand Up @@ -6169,12 +6176,11 @@ static void init_numa_sched_groups_power(struct sched_group *group_head)
}
#endif

#ifdef CONFIG_NUMA
/* Free memory allocated for various sched_group structures */
static void free_sched_groups(const cpumask_t *cpu_map)
{
int cpu;
#ifdef CONFIG_NUMA
int i;
int cpu, i;

for_each_cpu_mask(cpu, *cpu_map) {
struct sched_group *sched_group_allnodes
Expand Down Expand Up @@ -6211,20 +6217,12 @@ static void free_sched_groups(const cpumask_t *cpu_map)
kfree(sched_group_nodes);
sched_group_nodes_bycpu[cpu] = NULL;
}
#endif
for_each_cpu_mask(cpu, *cpu_map) {
if (sched_group_phys_bycpu[cpu]) {
kfree(sched_group_phys_bycpu[cpu]);
sched_group_phys_bycpu[cpu] = NULL;
}
#ifdef CONFIG_SCHED_MC
if (sched_group_core_bycpu[cpu]) {
kfree(sched_group_core_bycpu[cpu]);
sched_group_core_bycpu[cpu] = NULL;
}
#endif
}
}
#else
static void free_sched_groups(const cpumask_t *cpu_map)
{
}
#endif

/*
* Build sched domains for a given set of cpus and attach the sched domains
Expand All @@ -6233,10 +6231,6 @@ static void free_sched_groups(const cpumask_t *cpu_map)
static int build_sched_domains(const cpumask_t *cpu_map)
{
int i;
struct sched_group *sched_group_phys = NULL;
#ifdef CONFIG_SCHED_MC
struct sched_group *sched_group_core = NULL;
#endif
#ifdef CONFIG_NUMA
struct sched_group **sched_group_nodes = NULL;
struct sched_group *sched_group_allnodes = NULL;
Expand Down Expand Up @@ -6282,7 +6276,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
sd = &per_cpu(allnodes_domains, i);
*sd = SD_ALLNODES_INIT;
sd->span = *cpu_map;
group = cpu_to_allnodes_group(i);
group = cpu_to_allnodes_group(i, cpu_map);
sd->groups = &sched_group_allnodes[group];
p = sd;
} else
Expand All @@ -6295,42 +6289,18 @@ static int build_sched_domains(const cpumask_t *cpu_map)
cpus_and(sd->span, sd->span, *cpu_map);
#endif

if (!sched_group_phys) {
sched_group_phys
= kmalloc(sizeof(struct sched_group) * NR_CPUS,
GFP_KERNEL);
if (!sched_group_phys) {
printk (KERN_WARNING "Can not alloc phys sched"
"group\n");
goto error;
}
sched_group_phys_bycpu[i] = sched_group_phys;
}

p = sd;
sd = &per_cpu(phys_domains, i);
group = cpu_to_phys_group(i);
group = cpu_to_phys_group(i, cpu_map);
*sd = SD_CPU_INIT;
sd->span = nodemask;
sd->parent = p;
sd->groups = &sched_group_phys[group];

#ifdef CONFIG_SCHED_MC
if (!sched_group_core) {
sched_group_core
= kmalloc(sizeof(struct sched_group) * NR_CPUS,
GFP_KERNEL);
if (!sched_group_core) {
printk (KERN_WARNING "Can not alloc core sched"
"group\n");
goto error;
}
sched_group_core_bycpu[i] = sched_group_core;
}

p = sd;
sd = &per_cpu(core_domains, i);
group = cpu_to_core_group(i);
group = cpu_to_core_group(i, cpu_map);
*sd = SD_MC_INIT;
sd->span = cpu_coregroup_map(i);
cpus_and(sd->span, sd->span, *cpu_map);
Expand All @@ -6341,7 +6311,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
#ifdef CONFIG_SCHED_SMT
p = sd;
sd = &per_cpu(cpu_domains, i);
group = cpu_to_cpu_group(i);
group = cpu_to_cpu_group(i, cpu_map);
*sd = SD_SIBLING_INIT;
sd->span = cpu_sibling_map[i];
cpus_and(sd->span, sd->span, *cpu_map);
Expand All @@ -6359,7 +6329,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
continue;

init_sched_build_groups(sched_group_cpus, this_sibling_map,
&cpu_to_cpu_group);
cpu_map, &cpu_to_cpu_group);
}
#endif

Expand All @@ -6371,7 +6341,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
if (i != first_cpu(this_core_map))
continue;
init_sched_build_groups(sched_group_core, this_core_map,
&cpu_to_core_group);
cpu_map, &cpu_to_core_group);
}
#endif

Expand All @@ -6385,14 +6355,14 @@ static int build_sched_domains(const cpumask_t *cpu_map)
continue;

init_sched_build_groups(sched_group_phys, nodemask,
&cpu_to_phys_group);
cpu_map, &cpu_to_phys_group);
}

#ifdef CONFIG_NUMA
/* Set up node groups */
if (sched_group_allnodes)
init_sched_build_groups(sched_group_allnodes, *cpu_map,
&cpu_to_allnodes_group);
cpu_map, &cpu_to_allnodes_group);

for (i = 0; i < MAX_NUMNODES; i++) {
/* Set up node groups */
Expand Down Expand Up @@ -6537,7 +6507,7 @@ static int build_sched_domains(const cpumask_t *cpu_map)
init_numa_sched_groups_power(sched_group_nodes[i]);

if (sched_group_allnodes) {
int group = cpu_to_allnodes_group(first_cpu(*cpu_map));
int group = cpu_to_allnodes_group(first_cpu(*cpu_map), cpu_map);
struct sched_group *sg = &sched_group_allnodes[group];

init_numa_sched_groups_power(sg);
Expand All @@ -6563,9 +6533,11 @@ static int build_sched_domains(const cpumask_t *cpu_map)

return 0;

#ifdef CONFIG_NUMA
error:
free_sched_groups(cpu_map);
return -ENOMEM;
#endif
}
/*
* Set up scheduler domains and groups. Callers must hold the hotplug lock.
Expand Down

0 comments on commit a616058

Please sign in to comment.