The patch titled
Subject: zsmalloc: skip chain size calculation for pow_of_2 classes
has been added to the -mm mm-unstable branch. Its filename is
zsmalloc-skip-chain-size-calculation-for-pow_of_2-classes.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zsmalloc-skip-chain-size-calculation-for-pow_of_2-classes.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Subject: zsmalloc: skip chain size calculation for pow_of_2 classes
Date: Mon, 9 Jan 2023 12:38:36 +0900
If a class size is power of 2 then it wastes no memory and the best
configuration is 1 physical page per-zspage.
Link: https://lkml.kernel.org/r/20230109033838.2779902-3-senozhatsky@xxxxxxxxxxxx
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/zsmalloc.c | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/zsmalloc.c~zsmalloc-skip-chain-size-calculation-for-pow_of_2-classes
+++ a/mm/zsmalloc.c
@@ -2287,6 +2287,9 @@ static int calculate_zspage_chain_size(i
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;
_
Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are
zram-correctly-handle-all-next_arg-cases.patch
zsmalloc-rework-zspage-chain-size-selection.patch
zsmalloc-skip-chain-size-calculation-for-pow_of_2-classes.patch
zsmalloc-make-zspage-chain-size-configurable.patch
zsmalloc-set-default-zspage-chain-size-to-8.patch
