cpu/mem hotplug: add try_online_node() for cpu_up()

cpu_up() has #ifdef CONFIG_MEMORY_HOTPLUG code blocks, which call
mem_online_node() to put its node online if offlined and then call
build_all_zonelists() to initialize the zone list.

These steps are specific to memory hotplug, and should be managed in
mm/memory_hotplug.c.  lock_memory_hotplug() should also be held for the
whole steps.

For this reason, this patch replaces mem_online_node() with
try_online_node(), which performs the whole steps with
lock_memory_hotplug() held.  try_online_node() is named after
try_offline_node() as they have similar purpose.

There is no functional change in this patch.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Toshi Kani
2013-11-12 15:07:25 -08:00
committed by Linus Torvalds
parent 309d0b3917
commit 01b0f19707
3 changed files with 24 additions and 29 deletions

View File

@@ -437,11 +437,6 @@ int cpu_up(unsigned int cpu)
{
int err = 0;
#ifdef CONFIG_MEMORY_HOTPLUG
int nid;
pg_data_t *pgdat;
#endif
if (!cpu_possible(cpu)) {
printk(KERN_ERR "can't online cpu %d because it is not "
"configured as may-hotadd at boot time\n", cpu);
@@ -452,27 +447,9 @@ int cpu_up(unsigned int cpu)
return -EINVAL;
}
#ifdef CONFIG_MEMORY_HOTPLUG
nid = cpu_to_node(cpu);
if (!node_online(nid)) {
err = mem_online_node(nid);
if (err)
return err;
}
pgdat = NODE_DATA(nid);
if (!pgdat) {
printk(KERN_ERR
"Can't online cpu %d due to NULL pgdat\n", cpu);
return -ENOMEM;
}
if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
mutex_lock(&zonelists_mutex);
build_all_zonelists(NULL, NULL);
mutex_unlock(&zonelists_mutex);
}
#endif
err = try_online_node(cpu_to_node(cpu));
if (err)
return err;
cpu_maps_update_begin();