From: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx> Install the callbacks via the state machine. Should the hotplug init fail then no threads are spawned. Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: linux-mm@xxxxxxxxx Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> --- 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>