From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: [Patch 3.14 stable 06/16] don't remove from shrink list in select_collect() Date: Thu, 6 Nov 2014 11:37:10 -0800 Message-ID: <1415302640-5876-7-git-send-email-xiyou.wangcong@gmail.com> References: <1415302640-5876-1-git-send-email-xiyou.wangcong@gmail.com> Cc: viro@zeniv.linux.org.uk, gregkh@linuxfoundation.org, linux-fsdevel@vger.kernel.org To: stable@vger.kernel.org Return-path: Received: from mail-pa0-f45.google.com ([209.85.220.45]:63543 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751325AbaKFThu (ORCPT ); Thu, 6 Nov 2014 14:37:50 -0500 In-Reply-To: <1415302640-5876-1-git-send-email-xiyou.wangcong@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: Al Viro If we find something already on a shrink list, just increment data->found and do nothing else. Loops in shrink_dcache_parent() and check_submounts_and_drop() will do the right thing - everything we did put into our list will be evicted and if there had been nothing, but data->found got non-zero, well, we have somebody else shrinking those guys; just try again. Signed-off-by: Al Viro (cherry picked from commit fe91522a7ba82ca1a51b07e19954b3825e4aaa22) --- fs/dcache.c | 31 ++++++++++--------------------- 1 file changed, 10 insertions(+), 21 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index 8fcf964..1c11c5e 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1228,34 +1228,23 @@ static enum d_walk_ret select_collect(void *_data, struct dentry *dentry) if (data->start == dentry) goto out; - /* - * move only zero ref count dentries to the dispose list. - * - * Those which are presently on the shrink list, being processed - * by shrink_dentry_list(), shouldn't be moved. Otherwise the - * loop in shrink_dcache_parent() might not make any progress - * and loop forever. - */ - if (dentry->d_lockref.count) { - dentry_lru_del(dentry); - } else if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) { - /* - * We can't use d_lru_shrink_move() because we - * need to get the global LRU lock and do the - * LRU accounting. - */ - d_lru_del(dentry); - d_shrink_add(dentry, &data->dispose); + if (dentry->d_flags & DCACHE_SHRINK_LIST) { data->found++; - ret = D_WALK_NORETRY; + } else { + if (dentry->d_flags & DCACHE_LRU_LIST) + d_lru_del(dentry); + if (!dentry->d_lockref.count) { + d_shrink_add(dentry, &data->dispose); + data->found++; + } } /* * We can return to the caller if we have found some (this * ensures forward progress). We'll be coming back to find * the rest. */ - if (data->found && need_resched()) - ret = D_WALK_QUIT; + if (!list_empty(&data->dispose)) + ret = need_resched() ? D_WALK_QUIT : D_WALK_NORETRY; out: return ret; } -- 1.8.3.1