[PATCH] pgdat allocation and update for ia64 of memory hotplug: update pgdat address array

This is to refresh node_data[] array for ia64.  As I mentioned previous
patches, ia64 has copies of information of pgdat address array on each node as
per node data.

At v2 of node_add, this function used stop_machine_run() to update them.  (I
wished that they were copied safety as much as possible.) But, in this patch,
this arrays are just copied simply, and set node_online_map bit after
completion of pgdat initialization.

So, kernel must touch NODE_DATA() macro after checking node_online_map().
(Current code has already done it.) This is more simple way for just
hot-add.....

Note : It will be problem when hot-remove will occur,
       because, even if online_map bit is set, kernel may
       touch NODE_DATA() due to race condition. :-(

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Yasunori Goto 2006-06-27 02:53:39 -07:00 committed by Linus Torvalds
parent ae5a2c1c9b
commit 7049027c6f
3 changed files with 32 additions and 8 deletions

View File

@ -308,6 +308,17 @@ static void __init reserve_pernode_space(void)
}
}
static void __meminit scatter_node_data(void)
{
pg_data_t **dst;
int node;
for_each_online_node(node) {
dst = LOCAL_DATA_ADDR(pgdat_list[node])->pg_data_ptrs;
memcpy(dst, pgdat_list, sizeof(pgdat_list));
}
}
/**
* initialize_pernode_data - fixup per-cpu & per-node pointers
*
@ -320,11 +331,8 @@ static void __init initialize_pernode_data(void)
{
int cpu, node;
/* Copy the pg_data_t list to each node and init the node field */
for_each_online_node(node) {
memcpy(mem_data[node].node_data->pg_data_ptrs, pgdat_list,
sizeof(pgdat_list));
}
scatter_node_data();
#ifdef CONFIG_SMP
/* Set the node_data pointer for each per-cpu struct */
for (cpu = 0; cpu < NR_CPUS; cpu++) {
@ -783,3 +791,9 @@ void __init paging_init(void)
zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
}
void arch_refresh_nodedata(int update_node, pg_data_t *update_pgdat)
{
pgdat_list[update_node] = update_pgdat;
scatter_node_data();
}

View File

@ -46,6 +46,18 @@ struct ia64_node_data {
*/
#define NODE_DATA(nid) (local_node_data->pg_data_ptrs[nid])
/*
* LOCAL_DATA_ADDR - This is to calculate the address of other node's
* "local_node_data" at hot-plug phase. The local_node_data
* is pointed by per_cpu_page. Kernel usually use it for
* just executing cpu. However, when new node is hot-added,
* the addresses of local data for other nodes are necessary
* to update all of them.
*/
#define LOCAL_DATA_ADDR(pgdat) \
((struct ia64_node_data *)((u64)(pgdat) + \
L1_CACHE_ALIGN(sizeof(struct pglist_data))))
#endif /* CONFIG_NUMA */
#endif /* _ASM_IA64_NODEDATA_H */

View File

@ -91,9 +91,7 @@ static inline pg_data_t *arch_alloc_nodedata(int nid)
static inline void arch_free_nodedata(pg_data_t *pgdat)
{
}
static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
{
}
extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */