diff mbox series

[PATCHv2,2/4] zsmalloc: skip chain size calculation for pow_of_2 classes

Message ID 20230109033838.2779902-3-senozhatsky@chromium.org (mailing list archive)
State New
Headers show
Series zsmalloc: make zspage chain size configurable | expand

Commit Message

Sergey Senozhatsky Jan. 9, 2023, 3:38 a.m. UTC 
If a class size is power of 2 then it wastes no memory
and the best configuration is 1 physical page per-zspage.

Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
---
 mm/zsmalloc.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Minchan Kim Jan. 13, 2023, 5:32 p.m. UTC | #1 
On Mon, Jan 09, 2023 at 12:38:36PM +0900, Sergey Senozhatsky wrote:
> If a class size is power of 2 then it wastes no memory
> and the best configuration is 1 physical page per-zspage.
> 
> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Minchan Kim <minchan@kernel.org>
diff mbox series

Patch

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index effe10fe76e9..ee8431784998 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -2287,6 +2287,9 @@  static int calculate_zspage_chain_size(int class_size)
 	int i, min_waste = INT_MAX;
 	int chain_size = 1;
 
+	if (is_power_of_2(class_size))
+		return chain_size;
+
 	for (i = 1; i <= ZS_MAX_PAGES_PER_ZSPAGE; i++) {
 		int waste;