[RFC3 05/14] Resurrect scan_control.may_swap

Christoph Lameter
2005-12-15T00:14:41Z

Resurrect may_swap in struct scan_control

Undo the patch to remove may_writepage from mm.

Signed-off-by: Christoph Lameter <clameter@sgi.com>

Index: linux-2.6.15-rc5-mm2/mm/vmscan.c
===================================================================
--- linux-2.6.15-rc5-mm2.orig/mm/vmscan.c 2005-12-14 14:57:29.000000000 -0800
+++ linux-2.6.15-rc5-mm2/mm/vmscan.c 2005-12-14 15:24:19.000000000 -0800
@@ -71,6 +71,9 @@ struct scan_control {

int may_writepage;

+ /* Can pages be swapped as part of reclaim? */
+ int may_swap;
+
/* This context's SWAP_CLUSTER_MAX. If freeing memory for
* suspend, we effectively ignore SWAP_CLUSTER_MAX.
* In this context, it doesn't matter that we scan the
@@ -458,6 +461,8 @@ static int shrink_list(struct list_head
* Try to allocate it some swap space here.
*/
if (PageAnon(page) && !PageSwapCache(page)) {
+ if (!sc->may_swap)
+ goto keep_locked;
if (!add_to_swap(page, GFP_ATOMIC))
goto activate_locked;
}
@@ -1415,6 +1420,7 @@ int try_to_free_pages(struct zone **zone

sc.gfp_mask = gfp_mask;
sc.may_writepage = 0;
+ sc.may_swap = 1;

inc_page_state(allocstall);

@@ -1517,6 +1523,7 @@ loop_again:
total_reclaimed = 0;
sc.gfp_mask = GFP_KERNEL;
sc.may_writepage = 0;
+ sc.may_swap = 1;
sc.nr_mapped = global_page_state(NR_MAPPED);

inc_page_state(pageoutrun);