On 07.12.21 17:36, Michal Hocko wrote:
On Tue 07-12-21 17:27:29, Michal Hocko wrote: [...]
So your proposal is to drop set_node_online from the patch and add it as a separate one which handles
- sysfs part (i.e. do not register a node which doesn't span a physical address space)
- hotplug side of (drop the pgd allocation, register node lazily when a first memblocks are registered)
In other words, the first stage diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c5952749ad40..f9024ba09c53 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6382,7 +6382,11 @@ static void __build_all_zonelists(void *data) if (self && !node_online(self->node_id)) { build_zonelists(self); } else {
for_each_online_node(nid) {
/** All possible nodes have pgdat preallocated* free_area_init*/for_each_node(nid) { pg_data_t *pgdat = NODE_DATA(nid);build_zonelists(pgdat); @@ -8032,8 +8036,24 @@ void __init free_area_init(unsigned long *max_zone_pfn) /* Initialise every node */ mminit_verify_pageflags_layout(); setup_nr_node_ids();
- for_each_online_node(nid) {
pg_data_t *pgdat = NODE_DATA(nid);
- for_each_node(nid) {
pg_data_t *pgdat;if (!node_online(nid)) {pr_warn("Node %d uninitialized by the platform. Please report with boot dmesg.\n", nid);pgdat = arch_alloc_nodedata(nid);
Is the buddy fully up an running at that point? I don't think so, so we might have to allocate via memblock instead. But I might be wrong.
pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);arch_refresh_nodedata(nid, pgdat);free_area_init_memoryless_node(nid);/** not marking this node online because we do not want to* confuse userspace by sysfs files/directories for node* without any memory attached to it (see topology_init)*/continue;}pgdat = NODE_DATA(nid);/* Any memory on that node */
Yes, and maybe in the same go, remove/rework hotadd_new_pgdat(), because there is nothing to hotadd anymore. (we should double-check the initialization performed in there, it might all not be necessary anymore)