Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756131AbcK3CAr (ORCPT ); Tue, 29 Nov 2016 21:00:47 -0500 Received: from szxga05-in.huawei.com ([119.145.14.199]:43479 "EHLO szxga05-in.huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751061AbcK3CAg (ORCPT ); Tue, 29 Nov 2016 21:00:36 -0500 Subject: Re: [PATCH 1/2] bcache: Remove redundant set_capacity To: Eric Wheeler References: <1480037969-45042-1-git-send-email-wangyijing@huawei.com> CC: , , , , , From: wangyijing Message-ID: <583E32AE.5060106@huawei.com> Date: Wed, 30 Nov 2016 10:00:14 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.177.23.4] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2943 Lines: 94 在 2016/11/30 4:49, Eric Wheeler 写道: > On Fri, 25 Nov 2016, Yijing Wang wrote: > >> set_capacity() has been called in bcache_device_init(), >> remove the redundant one. >> >> Signed-off-by: Yijing Wang >> --- >> drivers/md/bcache/super.c | 3 --- >> 1 file changed, 3 deletions(-) >> >> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c >> index 849ad44..b638a16 100644 >> --- a/drivers/md/bcache/super.c >> +++ b/drivers/md/bcache/super.c >> @@ -1126,9 +1126,6 @@ static int cached_dev_init(struct cached_dev *dc, unsigned block_size) >> if (ret) >> return ret; >> >> - set_capacity(dc->disk.disk, >> - dc->bdev->bd_part->nr_sects - dc->sb.data_offset); >> - > > It probably is a duplicate set_capacity, but has anyone tested bringing on > a writeback volume, and late-attaching the cache volume with this patch > applied? > > Otherwise stated, is it possible to get the backing device attached > without setting the capacity? Hi Eric, I tested this case in following steps, the result is fine, the capability is setted. [root@38 sys]# make-bcache -B /dev/nvme1n1 UUID: 6758bd42-c226-4de9-a6d5-fb003af63f9f Set UUID: 2661eadd-79b4-4c56-a2fb-9f8b505aa9fd version: 1 block_size: 1 data_offset: 16 [root@38 sys]# ls /dev/bcache bcache/ bcache0 [root@38 sys]# fdisk -l Disk /dev/nvme1n1: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes .... Disk /dev/bcache0: 1.8 TiB, 2000398925824 bytes, 3907029152 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes .... [root@38 sys]# make-bcache -C /dev/ram0 UUID: b64a4425-b9c1-4650-9cab-3856410c9566 Set UUID: a0a31965-a89d-43b6-a5d6-968897abeb7a version: 0 nbuckets: 1024 block_size: 1 bucket_size: 1024 nr_in_set: 1 nr_this_dev: 0 first_bucket: 1 [root@38 sys]# echo a0a31965-a89d-43b6-a5d6-968897abeb7a > /sys/block/bcache0/bcache/attach [root@38 sys]# echo writeback > /sys/block/bcache0/bcache/cache_mode [root@38 sys]# mount /dev/bcache0 /tmp [root@38 sys]# cd /tmp/ [root@38 tmp]# fio ~/fio_write.sh file1: (g=0): rw=randwrite, bs=4K-4K/4K-4K/4K-4K, ioengine=psync, iodepth=1 fio-2.2.8 Starting 1 thread file1: Laying out IO file(s) (1 file(s) / 128MB) Jobs: 1 (f=1): [w(1)] [0.0% done] [0KB/177.2MB/0KB /s] [0/45.4K/0 iops] [eta 05h:33m:13s] Thanks! Yijing. > > -Eric > >> dc->disk.disk->queue->backing_dev_info.ra_pages = >> max(dc->disk.disk->queue->backing_dev_info.ra_pages, >> q->backing_dev_info.ra_pages); >> -- >> 2.5.0 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-bcache" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > . >