mm: reduce try_to_compact_pages parameters

Expand the usage of the struct alloc_context introduced in the previous
patch also for calling try_to_compact_pages(), to reduce the number of its
parameters.  Since the function is in different compilation unit, we need
to move alloc_context definition in the shared mm/internal.h header.

With this change we get simpler code and small savings of code size and stack
usage:

add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-27 (-27)
function                                     old     new   delta
__alloc_pages_direct_compact                 283     256     -27
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-13 (-13)
function                                     old     new   delta
try_to_compact_pages                         582     569     -13

Stack usage of __alloc_pages_direct_compact goes from 24 to none (per
scripts/checkstack.pl).

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 25 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4aead0b..d664eb9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -232,27 +232,6 @@ EXPORT_SYMBOL(nr_node_ids);
 EXPORT_SYMBOL(nr_online_nodes);
 #endif
 
-/*
- * Structure for holding the mostly immutable allocation parameters passed
- * between alloc_pages* family of functions.
- *
- * nodemask, migratetype and high_zoneidx are initialized only once in
- * __alloc_pages_nodemask() and then never change.
- *
- * zonelist, preferred_zone and classzone_idx are set first in
- * __alloc_pages_nodemask() for the fast path, and might be later changed
- * in __alloc_pages_slowpath(). All other functions pass the whole strucure
- * by a const pointer.
- */
-struct alloc_context {
-	struct zonelist *zonelist;
-	nodemask_t *nodemask;
-	struct zone *preferred_zone;
-	int classzone_idx;
-	int migratetype;
-	enum zone_type high_zoneidx;
-};
-
 int page_group_by_mobility_disabled __read_mostly;
 
 void set_pageblock_migratetype(struct page *page, int migratetype)
@@ -2429,10 +2408,8 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
 		return NULL;
 
 	current->flags |= PF_MEMALLOC;
-	compact_result = try_to_compact_pages(ac->zonelist, order, gfp_mask,
-						ac->nodemask, mode,
-						contended_compaction,
-						alloc_flags, ac->classzone_idx);
+	compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac,
+						mode, contended_compaction);
 	current->flags &= ~PF_MEMALLOC;
 
 	switch (compact_result) {