path: root/mm/page_alloc.c
diff options
authorMel Gorman <>2021-04-29 23:01:42 -0700
committerLinus Torvalds <>2021-04-30 11:20:43 -0700
commitcb66bede617581309883432e9a633e8cade2a36e (patch)
tree2519acc487b67da6d3d0a8dbabb6e6dffabd9fb3 /mm/page_alloc.c
parent8f709dbdf9ff13da19d3154b3248e063364a53d5 (diff)
mm/page_alloc: rename alloced to allocated
Patch series "Introduce a bulk order-0 page allocator with two in-tree users", v6. This series introduces a bulk order-0 page allocator with sunrpc and the network page pool being the first users. The implementation is not efficient as semantics needed to be ironed out first. If no other semantic changes are needed, it can be made more efficient. Despite that, this is a performance-related for users that require multiple pages for an operation without multiple round-trips to the page allocator. Quoting the last patch for the high-speed networking use-case Kernel XDP stats CPU pps Delta Baseline XDP-RX CPU total 3,771,046 n/a List XDP-RX CPU total 3,940,242 +4.49% Array XDP-RX CPU total 4,249,224 +12.68% Via the SUNRPC traces of svc_alloc_arg() Single page: 25.007 us per call over 532,571 calls Bulk list: 6.258 us per call over 517,034 calls Bulk array: 4.590 us per call over 517,442 calls Both potential users in this series are corner cases (NFS and high-speed networks) so it is unlikely that most users will see any benefit in the short term. Other potential other users are batch allocations for page cache readahead, fault around and SLUB allocations when high-order pages are unavailable. It's unknown how much benefit would be seen by converting multiple page allocation calls to a single batch or what difference it may make to headline performance. Light testing of my own running dbench over NFS passed. Chuck and Jesper conducted their own tests and details are included in the changelogs. Patch 1 renames a variable name that is particularly unpopular Patch 2 adds a bulk page allocator Patch 3 adds an array-based version of the bulk allocator Patches 4-5 adds micro-optimisations to the implementation Patches 6-7 SUNRPC user Patches 8-9 Network page_pool user This patch (of 9): Review feedback of the bulk allocator twice found problems with "alloced" being a counter for pages allocated. The naming was based on the API name "alloc" and was based on the idea that verbal communication about malloc tends to use the fake word "malloced" instead of the fake word mallocated. To be consistent, this preparation patch renames alloced to allocated in rmqueue_bulk so the bulk allocator and per-cpu allocator use similar names when the bulk allocator is introduced. Link: Link: Signed-off-by: Mel Gorman <> Reviewed-by: Matthew Wilcox (Oracle) <> Reviewed-by: Alexander Lobakin <> Acked-by: Vlastimil Babka <> Cc: Chuck Lever <> Cc: Jesper Dangaard Brouer <> Cc: Christoph Hellwig <> Cc: Alexander Duyck <> Cc: Ilias Apalodimas <> Cc: David Miller <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'mm/page_alloc.c')
1 files changed, 4 insertions, 4 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8b24b69d55ef..fd283d9b6a4d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2949,7 +2949,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
unsigned long count, struct list_head *list,
int migratetype, unsigned int alloc_flags)
- int i, alloced = 0;
+ int i, allocated = 0;
for (i = 0; i < count; ++i) {
@@ -2972,7 +2972,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
* pages are ordered properly.
list_add_tail(&page->lru, list);
- alloced++;
+ allocated++;
if (is_migrate_cma(get_pcppage_migratetype(page)))
__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
-(1 << order));
@@ -2981,12 +2981,12 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
* i pages were removed from the buddy list even if some leak due
* to check_pcp_refill failing so adjust NR_FREE_PAGES based
- * on i. Do not confuse with 'alloced' which is the number of
+ * on i. Do not confuse with 'allocated' which is the number of
* pages added to the pcp list.
__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
- return alloced;
+ return allocated;