Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754473AbaFBLzv (ORCPT ); Mon, 2 Jun 2014 07:55:51 -0400 Received: from mail-pb0-f49.google.com ([209.85.160.49]:44749 "EHLO mail-pb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754186AbaFBLzt (ORCPT ); Mon, 2 Jun 2014 07:55:49 -0400 From: Chen Yucong To: shli@kernel.org Cc: hughd@google.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Chen Yucong Subject: [PATCH] swap: Delete the "last_in_cluster < scan_base" loop in the body of scan_swap_map() Date: Mon, 2 Jun 2014 19:54:13 +0800 Message-Id: <1401710053-8460-1-git-send-email-slaoub@gmail.com> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >From commit ebc2a1a69111, we can find that all SWP_SOLIDSTATE "seek is cheap"(SSD case) has already gone to si->cluster_info scan_swap_map_try_ssd_cluster() route. So that the "last_in_cluster < scan_base" loop in the body of scan_swap_map() has already become a dead code snippet, and it should have been deleted. This patch is to delete the redundant loop as Hugh and Shaohua suggested. Signed-off-by: Chen Yucong --- mm/swapfile.c | 20 -------------------- 1 file changed, 20 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index beeeef8..1b44bd9 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -549,26 +549,6 @@ static unsigned long scan_swap_map(struct swap_info_struct *si, } } - offset = si->lowest_bit; - last_in_cluster = offset + SWAPFILE_CLUSTER - 1; - - /* Locate the first empty (unaligned) cluster */ - for (; last_in_cluster < scan_base; offset++) { - if (si->swap_map[offset]) - last_in_cluster = offset + SWAPFILE_CLUSTER; - else if (offset == last_in_cluster) { - spin_lock(&si->lock); - offset -= SWAPFILE_CLUSTER - 1; - si->cluster_next = offset; - si->cluster_nr = SWAPFILE_CLUSTER - 1; - goto checks; - } - if (unlikely(--latency_ration < 0)) { - cond_resched(); - latency_ration = LATENCY_LIMIT; - } - } - offset = scan_base; spin_lock(&si->lock); si->cluster_nr = SWAPFILE_CLUSTER - 1; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/