From: Anna-Maria Gleixner <anna-ma...@linutronix.de>
Install the callbacks via the state machine. Should the hotplug init fail then
no threads are spawned.
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Vlastimil Babka <vba...@suse.cz>
Cc: Michal Hocko <mho...@suse.com>
Cc: Mel Gorman <mgor...@techsingularity.net>
Cc: linux...@kvack.org
Signed-off-by: Anna-Maria Gleixner <anna-ma...@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de>
---
mm/compaction.c | 31 ++++++++++++++++++-------------
1 file changed, 18 insertions(+), 13 deletions(-)
diff --git a/mm/compaction.c b/mm/compaction.c
index 0409a4ad6ea1..0d37192d9423 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -2043,33 +2043,38 @@ void kcompactd_stop(int nid)
* away, we get changed to run anywhere: as the first one comes back,
* restore their cpu bindings.
*/
-static int cpu_callback(struct notifier_block *nfb, unsigned long action,
- void *hcpu)
+static int kcompactd_cpu_online(unsigned int cpu)
{
int nid;
- if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) {
- for_each_node_state(nid, N_MEMORY) {
- pg_data_t *pgdat = NODE_DATA(nid);
- const struct cpumask *mask;
+ for_each_node_state(nid, N_MEMORY) {
+ pg_data_t *pgdat = NODE_DATA(nid);
+ const struct cpumask *mask;
- mask = cpumask_of_node(pgdat->node_id);
+ mask = cpumask_of_node(pgdat->node_id);
- if (cpumask_any_and(cpu_online_mask, mask) < nr_cpu_ids)
- /* One of our CPUs online: restore mask */
- set_cpus_allowed_ptr(pgdat->kcompactd, mask);
- }
+ if (cpumask_any_and(cpu_online_mask, mask) < nr_cpu_ids)
+ /* One of our CPUs online: restore mask */
+ set_cpus_allowed_ptr(pgdat->kcompactd, mask);
}
- return NOTIFY_OK;
+ return 0;
}
static int __init kcompactd_init(void)
{
int nid;
+ int ret;
+
+ ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+ "mm/compaction:online",
+ kcompactd_cpu_online, NULL);
+ if (ret < 0) {
+ pr_err("kcompactd: failed to register hotplug callbacks.\n");
+ return ret;
+ }
for_each_node_state(nid, N_MEMORY)
kcompactd_run(nid);
- hotcpu_notifier(cpu_callback, 0);
return 0;
}
subsys_initcall(kcompactd_init)
--
2.10.2
