[PATCH] sched_domai: Allocate sched_group structures dynamically

As explained here:
	http://marc.theaimsgroup.com/?l=linux-kernel&m=114327539012323&w=2

there is a problem with sharing sched_group structures between two
separate sched_group structures for different sched_domains.

The patch has been tested and found to avoid the kernel lockup problem
described in above URL.

Signed-off-by: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Srivatsa Vaddagiri 2006-06-27 02:54:41 -07:00 committed by Linus Torvalds
parent 15f0b676a4
commit 369381694d
1 changed files with 43 additions and 5 deletions

View File

@ -5747,7 +5747,7 @@ 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[NR_CPUS];
static struct sched_group *sched_group_core_bycpu[NR_CPUS];
#endif
#if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT)
@ -5763,7 +5763,7 @@ static int cpu_to_core_group(int cpu)
#endif
static DEFINE_PER_CPU(struct sched_domain, phys_domains);
static struct sched_group sched_group_phys[NR_CPUS];
static struct sched_group *sched_group_phys_bycpu[NR_CPUS];
static int cpu_to_phys_group(int cpu)
{
#if defined(CONFIG_SCHED_MC)
@ -5823,9 +5823,9 @@ next_sg:
/* 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;
for_each_cpu_mask(cpu, *cpu_map) {
struct sched_group *sched_group_allnodes
@ -5863,6 +5863,18 @@ next_sg:
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
}
}
/*
@ -5872,6 +5884,10 @@ next_sg:
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;
@ -5930,6 +5946,18 @@ 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);
@ -5939,6 +5967,18 @@ static int build_sched_domains(const cpumask_t *cpu_map)
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);
@ -6134,11 +6174,9 @@ 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.