[PATCH] mm/zsmalloc: strength reduce zspage_size calculation

From: Joey Pabalinas
Date: Mon Feb 26 2018 - 07:21:40 EST


Replace the repeated multiplication in the main loop
body calculation of zspage_size with an equivalent
(and cheaper) addition operation.

Signed-off-by: Joey Pabalinas <joeypabalinas@xxxxxxxxx>

1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index c3013505c30527dc42..647a1a2728634b5194 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -821,15 +821,15 @@ static enum fullness_group fix_fullness_group(struct size_class *class,
*/
static int get_pages_per_zspage(int class_size)
{
+ int zspage_size = 0;
int i, max_usedpc = 0;
/* zspage order which gives maximum used size per KB */
int max_usedpc_order = 1;

for (i = 1; i <= ZS_MAX_PAGES_PER_ZSPAGE; i++) {
- int zspage_size;
int waste, usedpc;

- zspage_size = i * PAGE_SIZE;
+ zspage_size += PAGE_SIZE;
waste = zspage_size % class_size;
usedpc = (zspage_size - waste) * 100 / zspage_size;

--
2.16.2

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