Trial the replicated pagecache on non-NUMA machines by doing per-CPU
replication. Actually there is a slight change in one algorithm because
there is no such thing as page_to_cpuid.
To minimise the code change, this just pretends smp_processor_id returns
a node id. Technically this will blow up if you have more CPUs than
MAX_NUMNODES.
mm/replication.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)
Index: linux-2.6/mm/replication.c
===================================================================
--- linux-2.6.orig/mm/replication.c
+++ linux-2.6/mm/replication.c
@@ -98,9 +98,6 @@ static int should_replicate_pcache(struc
if (unlikely(PageSwapCache(page)))
return 0;
- if (nid == page_to_nid(page))
- return 0;
-
if (page_count(page) != 2 + page_mapcount(page))
return 0;
smp_rmb();
@@ -133,7 +130,7 @@ static int try_to_replicate_pcache(struc
if (!pcd)
goto out;
- page_node = page_to_nid(page);
+ page_node = smp_processor_id();
pcd->master = page;
node_set(page_node, pcd->nodes_present);
if (radix_tree_insert(&pcd->page_tree, page_node, page))
@@ -143,7 +140,7 @@ static int try_to_replicate_pcache(struc
/* The non-racy check */
if (unlikely(!should_replicate_pcache(page, mapping, offset,
- numa_node_id())))
+ smp_processor_id())))
goto out_lock;
pslot = radix_tree_lookup_slot(&mapping->page_tree, offset);
@@ -269,13 +266,18 @@ failed:
static void __remove_replicated_page(struct pcache_desc *pcd, struct page
*page,
struct address_space *mapping, unsigned long offset)
{
- int nid = page_to_nid(page);
+ int nid;
BUG_ON(page == pcd->master);
- /* XXX: page->mapping = NULL; ? */
- BUG_ON(!node_isset(nid, pcd->nodes_present));
- BUG_ON(radix_tree_delete(&pcd->page_tree, nid) != page);
- node_clear(nid, pcd->nodes_present);
- __dec_zone_page_state(page, NR_REPL_PAGES);
+ for_each_node_mask(nid, pcd->nodes_present) {
+ /* XXX: page->mapping = NULL; ? */
+ if (radix_tree_lookup(&pcd->page_tree, nid) != page)
+ continue;
+ BUG_ON(radix_tree_delete(&pcd->page_tree, nid) != page);
+ node_clear(nid, pcd->nodes_present);
+ __dec_zone_page_state(page, NR_REPL_PAGES);
+ return;
+ }
+ BUG();
}
/*
@@ -309,8 +311,7 @@ static struct page *try_to_create_replic
{
struct page *repl_page;
- repl_page = alloc_pages_node(nid, mapping_gfp_mask(mapping) |
- __GFP_THISNODE | __GFP_NORETRY, 0);
+ repl_page = page_cache_alloc(mapping);
if (!repl_page)
return page; /* failed alloc, just return the master */
@@ -343,7 +344,7 @@ struct page * find_get_page_readonly(str
retry:
read_lock_irq(&mapping->tree_lock);
- nid = numa_node_id();
+ nid = smp_processor_id();
page = radix_tree_lookup(&mapping->page_tree, offset);
if (is_pcache_desc(page)) {
struct pcache_desc *pcd;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
