mm/vmscan: fix comment for isolate_lru_pages

Since commit 791b48b6 ("mm: vmscan: scan until it finds eligible
pages"), splicing any skipped pages to the tail of the LRU list won't put
the system at risk of premature OOM but will waste lots of cpu cycles. 
Correct the comment accordingly.

Link: https://lkml.kernel.org/r/20220416025231.8082-1-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmscan.c

@@ -2117,8 +2117,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
 	 * Splice any skipped pages to the start of the LRU list. Note that
 	 * this disrupts the LRU order when reclaiming for lower zones but
 	 * we cannot splice to the tail. If we did then the SWAP_CLUSTER_MAX
-	 * scanning would soon rescan the same pages to skip and put the
-	 * system at risk of premature OOM.
+	 * scanning would soon rescan the same pages to skip and waste lots
+	 * of cpu cycles.
 	 */
 	if (!list_empty(&pages_skipped)) {
 		int zid;