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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8B6BC433EF for ; Thu, 27 Jan 2022 11:12:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239896AbiA0LMW (ORCPT ); Thu, 27 Jan 2022 06:12:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59310 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229484AbiA0LMW (ORCPT ); Thu, 27 Jan 2022 06:12:22 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01ECBC061714; Thu, 27 Jan 2022 03:12:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 55F3DB821EE; Thu, 27 Jan 2022 11:12:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A0ECC340E4; Thu, 27 Jan 2022 11:12:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643281939; bh=V5HYgTWJFQ5JJsKuBtDbntq5jM8gqYnHqlB+WwVQUg0=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=qs+oygNUvOkZojCS4tbIHBbHNnN2c83jSwVTtC+PXReiKpUgTryV/Jn9i4kA11TCx wQIA8T/xXWysKr5FVnBsdp7s6T57gZuXoA8b+6AKW4GBWhPcMDiC878wFDfjGOUfSX 5ddnmsg5pr+FfS6jpyfRuWWfH+qIetrTGJZM1PAYwXCjUJyQB7D1Wcs5o++QKht+ze N6Qaj6XKvoxOKPWxiTmKIzgNkaDO61bAS7aaPRXf+qfG+7pz/a1932PlgtYdjIokd4 zXshthMZgvLd9Pe0iKyNgu1FzP9P91fWoKA6y5OydLOCZNYRF9sJ2Iz0TLFNBDx5FN vYRqTrnWEMhKw== Message-ID: <2e66ef3e8f5df0529d3c289f8ed0be6a051d95ea.camel@kernel.org> Subject: Re: [PATCH 5/9] cephfs: don't set/clear bdi_congestion From: Jeff Layton To: NeilBrown , Andrew Morton , Jaegeuk Kim , Chao Yu , Ilya Dryomov , Miklos Szeredi , Trond Myklebust , Anna Schumaker , Ryusuke Konishi , "Darrick J. Wong" , Philipp Reisner , Lars Ellenberg , Paolo Valente , Jens Axboe Cc: linux-mm@kvack.org, linux-nilfs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-ext4@vger.kernel.org, ceph-devel@vger.kernel.org, drbd-dev@lists.linbit.com, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org Date: Thu, 27 Jan 2022 06:12:15 -0500 In-Reply-To: <164325158958.29787.8840004338500709466.stgit@noble.brown> References: <164325106958.29787.4865219843242892726.stgit@noble.brown> <164325158958.29787.8840004338500709466.stgit@noble.brown> Content-Type: text/plain; charset="ISO-8859-15" User-Agent: Evolution 3.42.3 (3.42.3-1.fc35) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, 2022-01-27 at 13:46 +1100, NeilBrown wrote: > The bdi congestion framework is no-longer used - writeback uses other > mechanisms to manage throughput. > > So remove calls to set_bdi_congested() and clear_bdi_congested(), and > remove the writeback_count which is used only to guide the setting and > clearing. > > The congestion_kb mount option is no longer meaningful, but as it is > visible to user-space, removing it needs more consideration. > > Signed-off-by: NeilBrown > --- > fs/ceph/addr.c | 27 --------------------------- > fs/ceph/super.c | 2 -- > fs/ceph/super.h | 2 -- > 3 files changed, 31 deletions(-) > > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c > index c98e5238a1b6..9147667f8cd5 100644 > --- a/fs/ceph/addr.c > +++ b/fs/ceph/addr.c > @@ -57,11 +57,6 @@ > * accounting is preserved. > */ > > -#define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10)) > -#define CONGESTION_OFF_THRESH(congestion_kb) \ > - (CONGESTION_ON_THRESH(congestion_kb) - \ > - (CONGESTION_ON_THRESH(congestion_kb) >> 2)) > - > static int ceph_netfs_check_write_begin(struct file *file, loff_t pos, unsigned int len, > struct folio *folio, void **_fsdata); > > @@ -561,10 +556,6 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) > dout("writepage %p page %p index %lu on %llu~%llu snapc %p seq %lld\n", > inode, page, page->index, page_off, len, snapc, snapc->seq); > > - if (atomic_long_inc_return(&fsc->writeback_count) > > - CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb)) > - set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); > - > req = ceph_osdc_new_request(osdc, &ci->i_layout, ceph_vino(inode), page_off, &len, 0, 1, > CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE, snapc, > ceph_wbc.truncate_seq, ceph_wbc.truncate_size, > @@ -621,10 +612,6 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc) > ceph_put_wrbuffer_cap_refs(ci, 1, snapc); > ceph_put_snap_context(snapc); /* page's reference */ > > - if (atomic_long_dec_return(&fsc->writeback_count) < > - CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb)) > - clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); > - > return err; > } > > @@ -704,12 +691,6 @@ static void writepages_finish(struct ceph_osd_request *req) > BUG_ON(!page); > WARN_ON(!PageUptodate(page)); > > - if (atomic_long_dec_return(&fsc->writeback_count) < > - CONGESTION_OFF_THRESH( > - fsc->mount_options->congestion_kb)) > - clear_bdi_congested(inode_to_bdi(inode), > - BLK_RW_ASYNC); > - > ceph_put_snap_context(detach_page_private(page)); > end_page_writeback(page); > dout("unlocking %p\n", page); > @@ -952,14 +933,6 @@ static int ceph_writepages_start(struct address_space *mapping, > dout("%p will write page %p idx %lu\n", > inode, page, page->index); > > - if (atomic_long_inc_return(&fsc->writeback_count) > > - CONGESTION_ON_THRESH( > - fsc->mount_options->congestion_kb)) { > - set_bdi_congested(inode_to_bdi(inode), > - BLK_RW_ASYNC); > - } > - > - > pages[locked_pages++] = page; > pvec.pages[i] = NULL; > > diff --git a/fs/ceph/super.c b/fs/ceph/super.c > index bf79f369aec6..b2f38af9fca8 100644 > --- a/fs/ceph/super.c > +++ b/fs/ceph/super.c > @@ -801,8 +801,6 @@ static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt, > fsc->filp_gen = 1; > fsc->have_copy_from2 = true; > > - atomic_long_set(&fsc->writeback_count, 0); > - > err = -ENOMEM; > /* > * The number of concurrent works can be high but they don't need > diff --git a/fs/ceph/super.h b/fs/ceph/super.h > index 67f145e1ae7a..fc58adf1d36a 100644 > --- a/fs/ceph/super.h > +++ b/fs/ceph/super.h > @@ -120,8 +120,6 @@ struct ceph_fs_client { > > struct ceph_mds_client *mdsc; > > - atomic_long_t writeback_count; > - > struct workqueue_struct *inode_wq; > struct workqueue_struct *cap_wq; > > > Thanks Neil. I'll plan to pull this into the ceph testing branch and do some testing with it, but at a quick glance I don't forsee any issues. This should make v5.18, but we may be able to get it in sooner. -- Jeff Layton