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=-10.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 C7346C43461 for ; Fri, 11 Sep 2020 08:27:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86AC8221E3 for ; Fri, 11 Sep 2020 08:27:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725864AbgIKI13 (ORCPT ); Fri, 11 Sep 2020 04:27:29 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:12233 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725768AbgIKI1U (ORCPT ); Fri, 11 Sep 2020 04:27:20 -0400 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 5448876F5274B33334EF; Fri, 11 Sep 2020 16:27:16 +0800 (CST) Received: from [127.0.0.1] (10.174.179.103) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.487.0; Fri, 11 Sep 2020 16:27:09 +0800 Subject: Re: [RFC PATCH V4] iomap: add support to track dirty state of sub pages To: Matthew Wilcox CC: , , , , , , References: <20200821123306.1658495-1-yukuai3@huawei.com> <20200821124424.GQ17456@casper.infradead.org> From: "yukuai (C)" Message-ID: <7fb4bb5a-adc7-5914-3aae-179dd8f3adb1@huawei.com> Date: Fri, 11 Sep 2020 16:27:08 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20200821124424.GQ17456@casper.infradead.org> Content-Type: text/plain; charset="gbk"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.103] X-CFilter-Loop: Reflected Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 2020/08/21 20:44, Matthew Wilcox wrote: > On Fri, Aug 21, 2020 at 08:33:06PM +0800, Yu Kuai wrote: >> changes from v3: - add IOMAP_STATE_ARRAY_SIZE - replace set_bit / >> clear_bit with bitmap_set / bitmap_clear - move >> iomap_set_page_dirty() out of 'iop->state_lock' - merge >> iomap_set/clear_range_dirty() and >> iomap_iop_clear/clear_range_dirty() > > I'm still working on the iomap parts of the THP series (fixing up > invalidatepage right now), but here are some of the relevant bits > (patch series to follow) > Hi, Matthew Since your THP iomap patches were reviewed, I made some modifications based on these patches. Best regards, Yu Kuai --- fs/iomap/buffered-io.c | 92 +++++++++++++++++++++++++++++++++--------- 1 file changed, 74 insertions(+), 18 deletions(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index edf5eea56cf5..bc7f57748be8 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -23,13 +23,17 @@ /* * Structure allocated for each page or THP when block size < page size - * to track sub-page uptodate status and I/O completions. + * to track sub-page status and I/O completions. */ struct iomap_page { atomic_t read_bytes_pending; atomic_t write_bytes_pending; - spinlock_t uptodate_lock; - unsigned long uptodate[]; + spinlock_t state_lock; + /* + * The first half bits are used to track sub-page uptodate status, + * the second half bits are for dirty status. + */ + unsigned long state[]; }; static inline struct iomap_page *to_iomap_page(struct page *page) @@ -57,9 +61,9 @@ iomap_page_create(struct inode *inode, struct page *page) if (iop || nr_blocks <= 1) return iop; - iop = kzalloc(struct_size(iop, uptodate, BITS_TO_LONGS(nr_blocks)), + iop = kzalloc(struct_size(iop, state, BITS_TO_LONGS(2 * nr_blocks)), GFP_NOFS | __GFP_NOFAIL); - spin_lock_init(&iop->uptodate_lock); + spin_lock_init(&iop->state_lock); attach_page_private(page, iop); return iop; } @@ -74,7 +78,7 @@ iomap_page_release(struct page *page) return; WARN_ON_ONCE(atomic_read(&iop->read_bytes_pending)); WARN_ON_ONCE(atomic_read(&iop->write_bytes_pending)); - WARN_ON_ONCE(bitmap_full(iop->uptodate, nr_blocks) != + WARN_ON_ONCE(bitmap_full(iop->state, nr_blocks) != PageUptodate(page)); kfree(iop); } @@ -105,7 +109,7 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, /* move forward for each leading block marked uptodate */ for (i = first; i <= last; i++) { - if (!test_bit(i, iop->uptodate)) + if (!test_bit(i, iop->state)) break; *pos += block_size; poff += block_size; @@ -115,7 +119,7 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, /* truncate len if we find any trailing uptodate block(s) */ for ( ; i <= last; i++) { - if (test_bit(i, iop->uptodate)) { + if (test_bit(i, iop->state)) { plen -= (last - i + 1) * block_size; last = i - 1; break; @@ -139,6 +143,55 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, *lenp = plen; } +static void +iomap_set_range_dirty(struct page *page, unsigned int off, + unsigned int len) +{ + struct inode *inode = page->mapping->host; + unsigned int blocks_per_page = i_blocks_per_page(inode, page); + unsigned int first = (off >> inode->i_blkbits) + blocks_per_page; + unsigned int last = ((off + len - 1) >> inode->i_blkbits) + blocks_per_page; + unsigned long flags; + struct iomap_page *iop; + + if (PageError(page)) + return; + + if (len) + iomap_set_page_dirty(page); + + if (!page_has_private(page)) + return; + + iop = to_iomap_page(page); + spin_lock_irqsave(&iop->state_lock, flags); + bitmap_set(iop->state, first, last - first + 1); + spin_unlock_irqrestore(&iop->state_lock, flags); +} + +static void +iomap_clear_range_dirty(struct page *page, unsigned int off, + unsigned int len) +{ + struct inode *inode = page->mapping->host; + unsigned int blocks_per_page = i_blocks_per_page(inode, page); + unsigned int first = (off >> inode->i_blkbits) + blocks_per_page; + unsigned int last = ((off + len - 1) >> inode->i_blkbits) + blocks_per_page; + unsigned long flags; + struct iomap_page *iop; + + if (PageError(page)) + return; + + if (!page_has_private(page)) + return; + + iop = to_iomap_page(page); + spin_lock_irqsave(&iop->state_lock, flags); + bitmap_clear(iop->state, first, last - first + 1); + spin_unlock_irqrestore(&iop->state_lock, flags); +} + static void iomap_iop_set_range_uptodate(struct page *page, unsigned off, unsigned len) { @@ -148,11 +201,11 @@ iomap_iop_set_range_uptodate(struct page *page, unsigned off, unsigned len) unsigned last = (off + len - 1) >> inode->i_blkbits; unsigned long flags; - spin_lock_irqsave(&iop->uptodate_lock, flags); - bitmap_set(iop->uptodate, first, last - first + 1); - if (bitmap_full(iop->uptodate, i_blocks_per_page(inode, page))) + spin_lock_irqsave(&iop->state_lock, flags); + bitmap_set(iop->state, first, last - first + 1); + if (bitmap_full(iop->state, i_blocks_per_page(inode, page))) SetPageUptodate(page); - spin_unlock_irqrestore(&iop->uptodate_lock, flags); + spin_unlock_irqrestore(&iop->state_lock, flags); } static void @@ -445,7 +498,7 @@ iomap_is_partially_uptodate(struct page *page, unsigned long from, if (iop) { for (i = first; i <= last; i++) - if (!test_bit(i, iop->uptodate)) + if (!test_bit(i, iop->state)) return 0; return 1; } @@ -683,7 +736,7 @@ static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len, if (unlikely(copied < len && !PageUptodate(page))) return 0; iomap_set_range_uptodate(page, offset_in_page(pos), len); - iomap_set_page_dirty(page); + iomap_set_range_dirty(page, offset_in_page(pos), len); return copied; } @@ -997,7 +1050,6 @@ iomap_page_mkwrite_actor(struct inode *inode, loff_t pos, loff_t length, } else { WARN_ON_ONCE(!PageUptodate(page)); iomap_page_create(inode, page); - set_page_dirty(page); } return length; @@ -1007,7 +1059,7 @@ vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops) { struct page *page = vmf->page; struct inode *inode = file_inode(vmf->vma->vm_file); - unsigned long length; + unsigned int length, dirty_bits; loff_t offset; ssize_t ret; @@ -1016,6 +1068,7 @@ vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops) if (ret < 0) goto out_unlock; length = ret; + dirty_bits = ret; offset = page_offset(page); while (length > 0) { @@ -1028,6 +1081,7 @@ vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops) length -= ret; } + iomap_set_range_dirty(page, 0, dirty_bits); wait_for_stable_page(page); return VM_FAULT_LOCKED; out_unlock: @@ -1340,11 +1394,12 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, struct iomap_page *iop = to_iomap_page(page); struct iomap_ioend *ioend, *next; unsigned len = i_blocksize(inode); + unsigned int blocks_per_page = i_blocks_per_page(inode, page); u64 file_offset; /* file offset of page */ int error = 0, count = 0, i; LIST_HEAD(submit_list); - WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop); + WARN_ON_ONCE(blocks_per_page > 1 && !iop); WARN_ON_ONCE(iop && atomic_read(&iop->write_bytes_pending) != 0); /* @@ -1355,7 +1410,7 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, for (i = 0, file_offset = page_offset(page); i < (PAGE_SIZE >> inode->i_blkbits) && file_offset < end_offset; i++, file_offset += len) { - if (iop && !test_bit(i, iop->uptodate)) + if (iop && !test_bit(i, iop->state + blocks_per_page)) continue; error = wpc->ops->map_blocks(wpc, inode, file_offset); @@ -1404,6 +1459,7 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, */ set_page_writeback_keepwrite(page); } else { + iomap_clear_range_dirty(page, 0, PAGE_SIZE); clear_page_dirty_for_io(page); set_page_writeback(page); } -- 2.25.4 .