[PATCH 04/05] mm simplify __alloc_pages cpuset hardwall logic

Paul Jackson
2005-11-14T04:04:04Z

The __GFP_HARDWALL flag logic is the same in mm/page_alloc.c
for all calls to get_page_from_freelist(). Save a couple of
lines of source code and a few bytes of text by only computing
it once, inside get_page_from_freelist(), instead of passing
it in each time. The key improvement is that it reduces the
logic in __alloc_pages() by another detail. There is now -no-
cpuset specific confinement logic in __alloc_pages(). It is
all more generically stated in get_page_from_freelist().

Signed-off-by: Paul Jackson <pj@sgi.com>

---

mm/page_alloc.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)

--- 2.6.14-mm2.orig/mm/page_alloc.c 2005-11-13 10:10:59.147820307 -0800
+++ 2.6.14-mm2/mm/page_alloc.c 2005-11-13 10:11:02.926182092 -0800
@@ -815,6 +815,8 @@ get_page_from_freelist(gfp_t gfp_mask, u
*/
do {
if (!(alloc_flags & ALLOC_MUSTHAVE)) {
+ if (alloc_flags == ALLOC_DONT_DIP)
+ gfp_mask |= __GFP_HARDWALL;
if (!cpuset_zone_allowed(*z, gfp_mask))
continue;
if (!zone_watermark_ok(*z, order, (*z)->pages_low,
@@ -908,7 +910,7 @@ __alloc_pages(gfp_t gfp_mask, unsigned i
return NULL;
}
restart:
- page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
+ page = get_page_from_freelist(gfp_mask, order,
zonelist, ALLOC_DONT_DIP);
if (page)
goto got_pg;
@@ -987,7 +989,7 @@ rebalance:
* a parallel oom killing, we must fail if we're still
* under heavy pressure.
*/
- page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
+ page = get_page_from_freelist(gfp_mask, order,
zonelist, ALLOC_DONT_DIP);
if (page)
goto got_pg;

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.650.933.1373