lkml.org 
[lkml]   [2008]   [Oct]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 26/35] cpumask: get rid of boutique sched.c allocations, use cpumask_var_t.
Using lots of allocs rather than one big alloc is less efficient, but
who cares for this setup function?

From: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
---
kernel/sched.c | 133 ++++++++++++++++++++++++---------------------------------
1 file changed, 56 insertions(+), 77 deletions(-)
--- linux-2.6.28.orig/kernel/sched.c
+++ linux-2.6.28/kernel/sched.c
@@ -7291,40 +7291,6 @@ SD_INIT_FUNC(CPU)
SD_INIT_FUNC(MC)
#endif

-/*
- * To minimize stack usage kmalloc room for cpumasks and share the
- * space as the usage in build_sched_domains() dictates. Used only
- * if the amount of space is significant.
- */
-struct allmasks {
- cpumask_t tmpmask; /* make this one first */
- union {
- cpumask_t nodemask;
- cpumask_t this_sibling_map;
- cpumask_t this_core_map;
- };
- cpumask_t send_covered;
-
-#ifdef CONFIG_NUMA
- cpumask_t domainspan;
- cpumask_t covered;
- cpumask_t notcovered;
-#endif
-};
-
-#if NR_CPUS > 128
-#define SCHED_CPUMASK_ALLOC 1
-#define SCHED_CPUMASK_FREE(v) kfree(v)
-#define SCHED_CPUMASK_DECLARE(v) struct allmasks *v
-#else
-#define SCHED_CPUMASK_ALLOC 0
-#define SCHED_CPUMASK_FREE(v)
-#define SCHED_CPUMASK_DECLARE(v) struct allmasks _v, *v = &_v
-#endif
-
-#define SCHED_CPUMASK_VAR(v, a) cpumask_t *v = (cpumask_t *) \
- ((unsigned long)(a) + offsetof(struct allmasks, v))
-
static int default_relax_domain_level = -1;

static int __init setup_relax_domain_level(char *str)
@@ -7367,14 +7333,35 @@ static void set_domain_attribute(struct
static int __build_sched_domains(const cpumask_t *cpu_map,
struct sched_domain_attr *attr)
{
- int i;
+ int i, err = -ENOMEM;
struct root_domain *rd;
- SCHED_CPUMASK_DECLARE(allmasks);
- cpumask_t *tmpmask;
+ cpumask_var_t nodemask, this_sibling_map, this_core_map, send_covered,
+ tmpmask;
#ifdef CONFIG_NUMA
+ cpumask_var_t domainspan, covered, notcovered;
struct sched_group **sched_group_nodes = NULL;
int sd_allnodes = 0;

+ if (!alloc_cpumask_var(&domainspan, GFP_KERNEL))
+ goto out;
+ if (!alloc_cpumask_var(&covered, GFP_KERNEL))
+ goto free_domainspan;
+ if (!alloc_cpumask_var(&notcovered, GFP_KERNEL))
+ goto free_covered;
+#endif
+
+ if (!alloc_cpumask_var(&nodemask, GFP_KERNEL))
+ goto free_notcovered;
+ if (!alloc_cpumask_var(&this_sibling_map, GFP_KERNEL))
+ goto free_nodemask;
+ if (!alloc_cpumask_var(&this_core_map, GFP_KERNEL))
+ goto free_this_sibling_map;
+ if (!alloc_cpumask_var(&send_covered, GFP_KERNEL))
+ goto free_this_core_map;
+ if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
+ goto free_send_covered;
+
+#ifdef CONFIG_NUMA
/*
* Allocate the per-node list of sched groups
*/
@@ -7382,34 +7369,16 @@ static int __build_sched_domains(const c
GFP_KERNEL);
if (!sched_group_nodes) {
printk(KERN_WARNING "Can not alloc sched group node list\n");
- return -ENOMEM;
+ goto free_tmpmask;
}
#endif

rd = alloc_rootdomain();
if (!rd) {
printk(KERN_WARNING "Cannot alloc root domain\n");
-#ifdef CONFIG_NUMA
- kfree(sched_group_nodes);
-#endif
- return -ENOMEM;
+ goto free_sched_groups;
}

-#if SCHED_CPUMASK_ALLOC
- /* get space for all scratch cpumask variables */
- allmasks = kmalloc(sizeof(*allmasks), GFP_KERNEL);
- if (!allmasks) {
- printk(KERN_WARNING "Cannot alloc cpumask array\n");
- kfree(rd);
-#ifdef CONFIG_NUMA
- kfree(sched_group_nodes);
-#endif
- return -ENOMEM;
- }
-#endif
- tmpmask = (cpumask_t *)allmasks;
-
-
#ifdef CONFIG_NUMA
sched_group_nodes_bycpu[first_cpu(*cpu_map)] = sched_group_nodes;
#endif
@@ -7419,7 +7388,6 @@ static int __build_sched_domains(const c
*/
for_each_cpu(i, cpu_map) {
struct sched_domain *sd = NULL, *p;
- SCHED_CPUMASK_VAR(nodemask, allmasks);

*nodemask = node_to_cpumask(cpu_to_node(i));
cpus_and(*nodemask, *nodemask, *cpu_map);
@@ -7485,9 +7453,6 @@ static int __build_sched_domains(const c
#ifdef CONFIG_SCHED_SMT
/* Set up CPU (sibling) groups */
for_each_cpu(i, cpu_map) {
- SCHED_CPUMASK_VAR(this_sibling_map, allmasks);
- SCHED_CPUMASK_VAR(send_covered, allmasks);
-
*this_sibling_map = per_cpu(cpu_sibling_map, i);
cpus_and(*this_sibling_map, *this_sibling_map, *cpu_map);
if (i != first_cpu(*this_sibling_map))
@@ -7502,9 +7467,6 @@ static int __build_sched_domains(const c
#ifdef CONFIG_SCHED_MC
/* Set up multi-core groups */
for_each_cpu(i, cpu_map) {
- SCHED_CPUMASK_VAR(this_core_map, allmasks);
- SCHED_CPUMASK_VAR(send_covered, allmasks);
-
*this_core_map = cpu_coregroup_map(i);
cpus_and(*this_core_map, *this_core_map, *cpu_map);
if (i != first_cpu(*this_core_map))
@@ -7518,9 +7480,6 @@ static int __build_sched_domains(const c

/* Set up physical groups */
for (i = 0; i < nr_node_ids; i++) {
- SCHED_CPUMASK_VAR(nodemask, allmasks);
- SCHED_CPUMASK_VAR(send_covered, allmasks);
-
*nodemask = node_to_cpumask(i);
cpus_and(*nodemask, *nodemask, *cpu_map);
if (cpus_empty(*nodemask))
@@ -7534,8 +7493,6 @@ static int __build_sched_domains(const c
#ifdef CONFIG_NUMA
/* Set up node groups */
if (sd_allnodes) {
- SCHED_CPUMASK_VAR(send_covered, allmasks);
-
init_sched_build_groups(cpu_map, cpu_map,
&cpu_to_allnodes_group,
send_covered, tmpmask);
@@ -7544,9 +7501,6 @@ static int __build_sched_domains(const c
for (i = 0; i < nr_node_ids; i++) {
/* Set up node groups */
struct sched_group *sg, *prev;
- SCHED_CPUMASK_VAR(nodemask, allmasks);
- SCHED_CPUMASK_VAR(domainspan, allmasks);
- SCHED_CPUMASK_VAR(covered, allmasks);
int j;

*nodemask = node_to_cpumask(i);
@@ -7581,7 +7535,6 @@ static int __build_sched_domains(const c
prev = sg;

for (j = 0; j < nr_node_ids; j++) {
- SCHED_CPUMASK_VAR(notcovered, allmasks);
int n = (i + j) % nr_node_ids;
node_to_cpumask_ptr(pnodemask, n);

@@ -7660,14 +7613,40 @@ static int __build_sched_domains(const c
cpu_attach_domain(sd, rd, i);
}

- SCHED_CPUMASK_FREE((void *)allmasks);
- return 0;
+ err = 0;
+
+free_tmpmask:
+ free_cpumask_var(tmpmask);
+free_send_covered:
+ free_cpumask_var(send_covered);
+free_this_core_map:
+ free_cpumask_var(this_core_map);
+free_this_sibling_map:
+ free_cpumask_var(this_sibling_map);
+free_nodemask:
+ free_cpumask_var(nodemask);
+free_notcovered:
+#ifdef CONFIG_NUMA
+ free_cpumask_var(notcovered);
+free_covered:
+ free_cpumask_var(covered);
+free_domainspan:
+ free_cpumask_var(domainspan);
+out:
+#endif
+ return err;
+
+free_sched_groups:
+#ifdef CONFIG_NUMA
+ kfree(sched_group_nodes);
+#endif
+ goto free_tmpmask;

#ifdef CONFIG_NUMA
error:
free_sched_groups(cpu_map, tmpmask);
- SCHED_CPUMASK_FREE((void *)allmasks);
- return -ENOMEM;
+ kfree(rd);
+ goto free_tmpmask;
#endif
}

--


\
 
 \ /
  Last update: 2008-10-20 19:25    [from the cache]
©2003-2011 Jasper Spaans. Advertise on this site