From mboxrd@z Thu Jan 1 00:00:00 1970 From: He YunLei Subject: Re: [PATCH] f2fs: add a judgment in add_discard_addrs Date: Wed, 9 Sep 2015 07:53:31 +0800 Message-ID: <55EF74FB.8050600@huawei.com> References: <1441709473-21297-1-git-send-email-heyunlei@huawei.com> <001d01d0ea27$9d4c6cc0$d7e54640$@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1ZZSiH-0000Mq-8y for linux-f2fs-devel@lists.sourceforge.net; Tue, 08 Sep 2015 23:54:09 +0000 Received: from szxga03-in.huawei.com ([119.145.14.66]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1ZZSiE-0001Er-1o for linux-f2fs-devel@lists.sourceforge.net; Tue, 08 Sep 2015 23:54:09 +0000 In-Reply-To: <001d01d0ea27$9d4c6cc0$d7e54640$@samsung.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: Chao Yu Cc: jaegeuk@kernel.org, linux-f2fs-devel@lists.sourceforge.net On 2015/9/8 19:14, Chao Yu wrote: > Hi Yunlei, > >> -----Original Message----- >> From: Yunlei He [mailto:heyunlei@huawei.com] >> Sent: Tuesday, September 08, 2015 6:51 PM >> To: chao2.yu@samsung.com; jaegeuk@kernel.org; linux-f2fs-devel@lists.sourceforge.net >> Cc: bintian.wang@huawei.com; Yunlei He >> Subject: [f2fs-dev] [PATCH] f2fs: add a judgment in add_discard_addrs >> >> CP_DISCARD traverse all segments in fstrim_range to add small discards, >> it is better to select entry->len bigger than trim_minlen. > > If we mount with 'discard' option, f2fs will trigger real-time discard > when do checkpoint. If we add judgment condition here, fragmented invalid > blocks will not be discarded since we stop adding them in pending list > through __add_discard_entry. This judgment condition is only valid for cp reason CP_DISCARD, and has no influence to other checkpoint. The process of fstrim adds all invalid blocks in pending list and deletes entries which len < trim_minlen when issue discard. Can we do the selection when added? Thanks, > > Thanks, > >> >> Signed-off-by: Yunlei He >> --- >> fs/f2fs/segment.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c >> index 78e6d06..a0dab7a 100644 >> --- a/fs/f2fs/segment.c >> +++ b/fs/f2fs/segment.c >> @@ -599,7 +599,8 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control >> *cpc) >> break; >> >> end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1); >> - __add_discard_entry(sbi, cpc, se, start, end); >> + if(force && cpc->trim_minlen >= (end - start)) >> + __add_discard_entry(sbi, cpc, se, start, end); >> } >> } >> >> -- >> 1.9.1 > > > ------------------------------------------------------------------------------