linux-kernel - [PATCHv5 09/13] zram: remove redundant checks from zram

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Date:   Wed,  9 Nov 2022 20:50:43 +0900
From:   Sergey Senozhatsky <senozhatsky@...omium.org>
To:     Minchan Kim <minchan@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>
Cc:     Nitin Gupta <ngupta@...are.org>,
        Suleiman Souhlal <suleiman@...gle.com>,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        Sergey Senozhatsky <senozhatsky@...omium.org>
Subject: [PATCHv5 09/13] zram: remove redundant checks from zram_recompress()

Size class index comparison is powerful enough so we can
remove object size comparisons.

Signed-off-by: Sergey Senozhatsky <senozhatsky@...omium.org>
---
 drivers/block/zram/zram_drv.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 383d967ef4c7..67b58f2255db 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1725,9 +1725,7 @@ static int zram_recompress(struct zram *zram, u32 index, struct page *page,
 							comp_len_new);
 
 		/* Continue until we make progress */
-		if (comp_len_new >= huge_class_size ||
-		    comp_len_new >= comp_len_old ||
-		    class_index_new >= class_index_old ||
+		if (class_index_new >= class_index_old ||
 		    (threshold && comp_len_new >= threshold)) {
 			zcomp_stream_put(zram->comps[prio]);
 			continue;
@@ -1750,9 +1748,7 @@ static int zram_recompress(struct zram *zram, u32 index, struct page *page,
 	 * that would save memory, mark the object as incompressible so that
 	 * we will not try to compress it again.
 	 */
-	if (comp_len_new >= huge_class_size ||
-	    comp_len_new >= comp_len_old ||
-	    class_index_new >= class_index_old) {
+	if (class_index_new >= class_index_old) {
 		zram_set_flag(zram, index, ZRAM_INCOMPRESSIBLE);
 		return 0;
 	}
-- 
2.38.1.431.g37b22c650d-goog