diff mbox series

[RFC,1/5] mm: large system hash use vmalloc for size >MAX_ORDER when !hashdist

Message ID 20190515131944.12489-1-npiggin@gmail.com (mailing list archive)
State RFC
Headers show
Series [RFC,1/5] mm: large system hash use vmalloc for size >MAX_ORDER when !hashdist | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch success Successfully applied on branch next (8150a153c013aa2dd1ffae43370b89ac1347a7fb)
snowpatch_ozlabs/checkpatch success total: 0 errors, 0 warnings, 0 checks, 20 lines checked

Commit Message

Nicholas Piggin May 15, 2019, 1:19 p.m. UTC 
The kernel currently clamps large system hashes to MAX_ORDER when
hashdist is not set, which is rather arbitrary.

vmalloc space is limited on 32-bit machines, but this shouldn't
result in much more used because of small physical memory.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/page_alloc.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 59661106da16..1683d54d6405 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7978,7 +7978,7 @@  void *__init alloc_large_system_hash(const char *tablename,
 			else
 				table = memblock_alloc_raw(size,
 							   SMP_CACHE_BYTES);
-		} else if (hashdist) {
+		} else if (get_order(size) >= MAX_ORDER || hashdist) {
 			table = __vmalloc(size, gfp_flags, PAGE_KERNEL);
 		} else {
 			/*
@@ -7986,10 +7986,8 @@  void *__init alloc_large_system_hash(const char *tablename,
 			 * some pages at the end of hash table which
 			 * alloc_pages_exact() automatically does
 			 */
-			if (get_order(size) < MAX_ORDER) {
-				table = alloc_pages_exact(size, gfp_flags);
-				kmemleak_alloc(table, size, 1, gfp_flags);
-			}
+			table = alloc_pages_exact(size, gfp_flags);
+			kmemleak_alloc(table, size, 1, gfp_flags);
 		}
 	} while (!table && size > PAGE_SIZE && --log2qty);