[PATCH] Remove special case in kmem_getpages()

[Brian Gerst]

Matthew Wilcox wrote:
__get_free_pages() calls alloc_pages, finds the page_address() and
throws away the struct page *.  Slab then calls virt_to_page to get it
back again.  Much more efficient for slab to call alloc_pages itself,
as well as making the NUMA and non-NUMA cases more similarr to each other.
Here is a better patch:
Remove the special case of nodeid == -1.  Instead, use numa_node_id() 
when calling cache_grow().

Signed-off-by: Brian Gerst <[EMAIL PROTECTED]>
diff -urN linux-2.6.11-rc2-bk/mm/slab.c linux/mm/slab.c
--- linux-2.6.11-rc2-bk/mm/slab.c       2005-01-22 01:58:25.000000000 -0500
+++ linux/mm/slab.c     2005-01-24 15:35:08.000000000 -0500
@@ -893,17 +893,11 @@
        int i;
 
        flags |= cachep->gfpflags;
-       if (likely(nodeid == -1)) {
-               addr = (void*)__get_free_pages(flags, cachep->gfporder);
-               if (!addr)
-                       return NULL;
-               page = virt_to_page(addr);
-       } else {
-               page = alloc_pages_node(nodeid, flags, cachep->gfporder);
-               if (!page)
-                       return NULL;
-               addr = page_address(page);
-       }
+
+       page = alloc_pages_node(nodeid, flags, cachep->gfporder);
+       if (!page)
+               return NULL;
+       addr = page_address(page);
 
        i = (1 << cachep->gfporder);
        if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
@@ -2065,7 +2059,7 @@
 
        if (unlikely(!ac->avail)) {
                int x;
-               x = cache_grow(cachep, flags, -1);
+               x = cache_grow(cachep, flags, numa_node_id());
                
                // cache_grow can reenable interrupts, then ac could change.
                ac = ac_data(cachep);