From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 80F78C43381 for ; Wed, 6 Mar 2019 14:32:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 50A9A206DD for ; Wed, 6 Mar 2019 14:32:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551882756; bh=zmUl9roF2mGOw3ls2jllrFxkyAtWm6aKTsVJHo9FB0k=; h=Subject:To:Cc:References:From:Date:In-Reply-To:List-ID:From; b=vy8FuweLLiBXupmILzXyhBSU01pPz8i3VimJ0C70VNjKo1lFGToRPufslJfnkKUUn AETlUS4tjcMX13tRnxYOXuei3Mg+TnJFlP2+8RJ378DOdW2HP5qlnK2loM2IRVwLM4 SY0mWX1HtEw8zeACSjPvPwNKxRFLdRWNrKNXu/Bs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727069AbfCFOcf (ORCPT ); Wed, 6 Mar 2019 09:32:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:43024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727036AbfCFOcf (ORCPT ); Wed, 6 Mar 2019 09:32:35 -0500 Received: from [192.168.0.101] (unknown [49.77.183.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3BA1F20684; Wed, 6 Mar 2019 14:32:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551882753; bh=zmUl9roF2mGOw3ls2jllrFxkyAtWm6aKTsVJHo9FB0k=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=pQ2CYSuzx4MNzOCidT2zzfn/1YOiQG6vLZCrBJMf+JyqD5uOPfiY8j+W6PYbtDozX VtwAjVlWPrvi6sbflpoJ+q5ALDISKGXfUSszGkQFjQxIxarNufjEyKpqeGBieXgDI6 8IU31CbfIDNn6czlAGnc2v/RpOpb8+oeoty2Cy2I= Subject: Re: [f2fs-dev] [PATCH v2] f2fs: Reduce zoned block device memory usage To: Damien Le Moal , jaegeuk@kernel.org, yuchao0@huawei.com, linux-f2fs-devel@lists.sourceforge.net Cc: linux-fsdevel@vger.kernel.org, Matias Bjorling References: <20190306062711.14456-1-damien.lemoal@wdc.com> From: Chao Yu Message-ID: Date: Wed, 6 Mar 2019 22:32:22 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190306062711.14456-1-damien.lemoal@wdc.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 2019-3-6 14:27, Damien Le Moal wrote: > For zoned block devices, an array of zone types for each device is > allocated and initialized in order to determine if a section is stored > on a sequential zone (zone reset needed) or a conventional zone (no > zone reset needed and regular discard applies). Considering this usage, > the zone types stored in memory can be replaced with a bitmap to > indicate an equivalent information, that is, if a zone is sequential or > not. This reduces the memory usage for each zoned device by roughly 8: > on a 14TB disk with zones of 256 MB, the zone type array consumes > 13x4KB pages while the bitmap uses only 2x4KB pages. > > This patch changes the f2fs_dev_info structure blkz_type field to the > bitmap blkz_seq. Access to this bitmap is done using the helper > function f2fs_blkz_is_seq(), which is a rewrite of the function > get_blkz_type(). > > Signed-off-by: Damien Le Moal > --- > Changes from v1: > * Use kvfree() instead of kfree() to free the zone bitmap > > fs/f2fs/f2fs.h | 13 +++++++------ > fs/f2fs/segment.c | 23 +++++++---------------- > fs/f2fs/super.c | 13 ++++++++----- > 3 files changed, 22 insertions(+), 27 deletions(-) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 12fabd6735dd..d7b2de930352 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -1067,8 +1067,8 @@ struct f2fs_dev_info { > block_t start_blk; > block_t end_blk; > #ifdef CONFIG_BLK_DEV_ZONED > - unsigned int nr_blkz; /* Total number of zones */ > - u8 *blkz_type; /* Array of zones type */ > + unsigned int nr_blkz; /* Total number of zones */ > + unsigned long *blkz_seq; /* Bitmap indicating sequential zones */ > #endif > }; > > @@ -3508,16 +3508,17 @@ F2FS_FEATURE_FUNCS(lost_found, LOST_FOUND); > F2FS_FEATURE_FUNCS(sb_chksum, SB_CHKSUM); > > #ifdef CONFIG_BLK_DEV_ZONED > -static inline int get_blkz_type(struct f2fs_sb_info *sbi, > - struct block_device *bdev, block_t blkaddr) > +static inline bool f2fs_blkz_is_seq(struct f2fs_sb_info *sbi, > + struct block_device *bdev, block_t blkaddr) > { > unsigned int zno = blkaddr >> sbi->log_blocks_per_blkz; > int i; > > for (i = 0; i < sbi->s_ndevs; i++) > if (FDEV(i).bdev == bdev) > - return FDEV(i).blkz_type[zno]; > - return -EINVAL; > + return test_bit(zno, FDEV(i).blkz_seq); > + WARN_ON_ONCE(1); > + return false; How about just handling this case as previous instead of treating device as conventional zone? Thanks, > } > #endif > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 9b79056d705d..65941070776c 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -1703,19 +1703,8 @@ static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi, > blkstart -= FDEV(devi).start_blk; > } > > - /* > - * We need to know the type of the zone: for conventional zones, > - * use regular discard if the drive supports it. For sequential > - * zones, reset the zone write pointer. > - */ > - switch (get_blkz_type(sbi, bdev, blkstart)) { > - > - case BLK_ZONE_TYPE_CONVENTIONAL: > - if (!blk_queue_discard(bdev_get_queue(bdev))) > - return 0; > - return __queue_discard_cmd(sbi, bdev, lblkstart, blklen); > - case BLK_ZONE_TYPE_SEQWRITE_REQ: > - case BLK_ZONE_TYPE_SEQWRITE_PREF: > + /* For sequential zones, reset the zone write pointer */ > + if (f2fs_blkz_is_seq(sbi, bdev, blkstart)) { > sector = SECTOR_FROM_BLOCK(blkstart); > nr_sects = SECTOR_FROM_BLOCK(blklen); > > @@ -1730,10 +1719,12 @@ static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi, > trace_f2fs_issue_reset_zone(bdev, blkstart); > return blkdev_reset_zones(bdev, sector, > nr_sects, GFP_NOFS); > - default: > - /* Unknown zone type: broken device ? */ > - return -EIO; > } > + > + /* For conventional zones, use regular discard if supported */ > + if (!blk_queue_discard(bdev_get_queue(bdev))) > + return 0; > + return __queue_discard_cmd(sbi, bdev, lblkstart, blklen); > } > #endif > > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c > index c46a1d4318d4..91d7429be554 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -1017,7 +1017,7 @@ static void destroy_device_list(struct f2fs_sb_info *sbi) > for (i = 0; i < sbi->s_ndevs; i++) { > blkdev_put(FDEV(i).bdev, FMODE_EXCL); > #ifdef CONFIG_BLK_DEV_ZONED > - kvfree(FDEV(i).blkz_type); > + kvfree(FDEV(i).blkz_seq); > #endif > } > kvfree(sbi->devs); > @@ -2765,9 +2765,11 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi) > if (nr_sectors & (bdev_zone_sectors(bdev) - 1)) > FDEV(devi).nr_blkz++; > > - FDEV(devi).blkz_type = f2fs_kmalloc(sbi, FDEV(devi).nr_blkz, > - GFP_KERNEL); > - if (!FDEV(devi).blkz_type) > + FDEV(devi).blkz_seq = f2fs_kzalloc(sbi, > + BITS_TO_LONGS(FDEV(devi).nr_blkz) > + * sizeof(unsigned long), > + GFP_KERNEL); > + if (!FDEV(devi).blkz_seq) > return -ENOMEM; > > #define F2FS_REPORT_NR_ZONES 4096 > @@ -2794,7 +2796,8 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi) > } > > for (i = 0; i < nr_zones; i++) { > - FDEV(devi).blkz_type[n] = zones[i].type; > + if (zones[i].type != BLK_ZONE_TYPE_CONVENTIONAL) > + set_bit(n, FDEV(devi).blkz_seq); > sector += zones[i].len; > n++; > } >