lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

sched: convert falback_doms to cpumask_var_t.

Browse Source 
Impact: (future) size reduction for large NR_CPUS.

Dynamically allocating cpumasks (when CONFIG_CPUMASK_OFFSTACK) saves
space for small nr_cpu_ids but big CONFIG_NR_CPUS.  cpumask_var_t
is just a struct cpumask for !CONFIG_CPUMASK_OFFSTACK.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Rusty Russell
2008-11-25 02:35:12 +10:30
committed by Ingo Molnar
parent dcc30a35f7
commit 4212823fb4
1 changed files with 8 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
kernel/sched.c
View File

@@ -7697,10 +7697,10 @@ static struct sched_domain_attr *dattr_cur;
/* /*
* Special case: If a kmalloc of a doms_cur partition (array of * Special case: If a kmalloc of a doms_cur partition (array of
* cpumask_t) fails, then fallback to a single sched domain, * cpumask) fails, then fallback to a single sched domain,
* as determined by the single cpumask_t fallback_doms. * as determined by the single cpumask fallback_doms.
*/ */
static cpumask_t fallback_doms; static cpumask_var_t fallback_doms;
void __attribute__((weak)) arch_update_cpu_topology(void) void __attribute__((weak)) arch_update_cpu_topology(void)
{ {
@@ -7719,7 +7719,7 @@ static int arch_init_sched_domains(const cpumask_t *cpu_map)
ndoms_cur = 1; ndoms_cur = 1;
doms_cur = kmalloc(sizeof(cpumask_t), GFP_KERNEL); doms_cur = kmalloc(sizeof(cpumask_t), GFP_KERNEL);
if (!doms_cur) if (!doms_cur)
doms_cur = &fallback_doms; doms_cur = fallback_doms;
cpumask_andnot(doms_cur, cpu_map, cpu_isolated_map); cpumask_andnot(doms_cur, cpu_map, cpu_isolated_map);
dattr_cur = NULL; dattr_cur = NULL;
err = build_sched_domains(doms_cur); err = build_sched_domains(doms_cur);
@@ -7818,7 +7818,7 @@ match1:
if (doms_new == NULL) { if (doms_new == NULL) {
ndoms_cur = 0; ndoms_cur = 0;
doms_new = &fallback_doms; doms_new = fallback_doms;
cpumask_andnot(&doms_new[0], cpu_online_mask, cpu_isolated_map); cpumask_andnot(&doms_new[0], cpu_online_mask, cpu_isolated_map);
WARN_ON_ONCE(dattr_new); WARN_ON_ONCE(dattr_new);
} }
@@ -7838,7 +7838,7 @@ match2:
} }
/* Remember the new sched domains */ /* Remember the new sched domains */
if (doms_cur != &fallback_doms) if (doms_cur != fallback_doms)
kfree(doms_cur); kfree(doms_cur);
kfree(dattr_cur); /* kfree(NULL) is safe */ kfree(dattr_cur); /* kfree(NULL) is safe */
doms_cur = doms_new; doms_cur = doms_new;
@@ -8011,6 +8011,8 @@ void __init sched_init_smp(void)
BUG(); BUG();
sched_init_granularity(); sched_init_granularity();
free_cpumask_var(non_isolated_cpus); free_cpumask_var(non_isolated_cpus);
alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
} }
#else #else
void __init sched_init_smp(void) void __init sched_init_smp(void)