From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5150326ED33 for ; Mon, 31 Aug 2026 04:21:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788150076; cv=none; b=hxwvvPkOvZQxFXN0Jpnshz8GehUt7+wdj3TgQjUFrIc8USEH0sGgqZ7av1tNurEdzy/iQ7IpqWVgTgcaZN4JS1/cItzTXu/sYJKVdY6vigONMbFPPA/L6Ce6kLv/2NiIctW8Xg4vTYVffwvFSgF0E7g99hjbLLl+Sp2ghGr+u4o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788150076; c=relaxed/simple; bh=Vtl4LlDo1XuCJYHVHwQ2BeZm6J4wvrsat+nCsNAsaVw=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=PiaJ7XSKsUv18rqGBsJp9a6bFjouAsAiOBuL6uYbqQ8hxwPAcwm/ZmGVgHvPc95KnIqtje1ilF4CH2RmUJra54utE0C4/xzl3QfZ98WxuCw9VhE9k67d9NnCdaIMNjd3FAJYBsxTaT+BXdZyO/QqxVFX1RGIMwYSjA3qyQK+E6M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bPyOlk8N; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bPyOlk8N" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B27301F000E9; Mon, 31 Aug 2026 04:21:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788150074; bh=D/srB2qi/xGyHk8KhxL5VY+I1yXbGPQR9sondW4gNOo=; h=Date:Cc:Subject:To:References:From:In-Reply-To; b=bPyOlk8Np3eKUUfbA/io087Yiuhm+gibwpUYJ+X1Kvm18AahJGiStMGcn0CbbEb+E 2fZi/kgorvK77XDLEN4Z5Qz5cUInm8DgppI2bHCaW+kKR1vYg/4IdPt2j+upcVDKQ/ NhaHTMzZ7fvwOYY2B7PmbO9pGI+o0sKrHGmUc9MSYzu4VMB4j738LfJV1kv7UIocFl bblNKHuxAWcXjY0FFKisMtwp7xvEgK5MN5n8jR1dlXA7pmOfcS0OnWwdGsI59B+0B3 YLxIrWzTohE6zIrGdU7w38vfHSQM9FNjERcngiB8xtDDiy/ITmyizVhfXJ3MdEtnDJ amEA3k3XafSRg== Message-ID: Date: Mon, 31 Aug 2026 12:21:11 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, Barry Song , Nanzhe Zhao , Juan Yescas , Dev Jain , linux-kernel@vger.kernel.org, David Hildenbrand , Bo Zhang , Kalesh Singh , Ryan Roberts , Pengfei Li Subject: Re: [PATCH 08/14] f2fs: optimize small block size large folio read To: Nanzhe Zhao , linux-f2fs-devel@lists.sourceforge.net, Jaegeuk Kim References: <20260826082641.2007658-1-zhaonanzhe@xiaomi.com> <20260826082641.2007658-9-zhaonanzhe@xiaomi.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20260826082641.2007658-9-zhaonanzhe@xiaomi.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/26/26 16:26, Nanzhe Zhao wrote: > The original f2fs_read_data_large_folio() implementation has limited > benefit with a 4KB block size, mainly because updating > read_pages_pending greatly increases the number of spinlock > operations. > > Use len_blks to batch read_pages_pending and iostat updates for > contiguous mapped blocks. If the contiguous mapping covers the whole > folio, skip f2fs_folio_state allocation for that folio. > > Signed-off-by: Nanzhe Zhao > --- > fs/f2fs/data.c | 62 ++++++++++++++++++++++++++++++++++++++------------ > 1 file changed, 47 insertions(+), 15 deletions(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 0e54b1e25893..48c1bb6c02e3 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -153,6 +153,7 @@ static void f2fs_finish_read_bio(struct bio *bio, bool in_task) > struct folio *folio = fi.folio; > unsigned int nr_pages = fi.length >> PAGE_SHIFT; > bool finished = true; > + bool uptodate = bio->bi_status == BLK_STS_OK; > > if (!folio_test_large(folio) && > f2fs_is_compressed_page(folio)) { > @@ -163,10 +164,14 @@ static void f2fs_finish_read_bio(struct bio *bio, bool in_task) > continue; > } > > - if (folio_test_large(folio)) { > - struct f2fs_folio_state *ffs = folio->private; > + if (f2fs_folio_has_ffs(folio)) { > + struct f2fs_folio_state *ffs = > + (struct f2fs_folio_state *)folio->private; > > spin_lock_irqsave(&ffs->state_lock, flags); > + if (bio->bi_status == BLK_STS_OK) > + uptodate = __ffs_mark_subrange_uptodate(folio, ffs, > + fi.offset, fi.length); > ffs->read_pages_pending -= nr_pages; > finished = !ffs->read_pages_pending; > spin_unlock_irqrestore(&ffs->state_lock, flags); > @@ -182,7 +187,7 @@ static void f2fs_finish_read_bio(struct bio *bio, bool in_task) > bio->bi_status = BLK_STS_IOERR; > > if (finished) > - folio_end_read(folio, bio->bi_status == BLK_STS_OK); folio_end_read(folio, bio->bi_status == BLK_STS_OK && uptodate); in case f2fs_sanity_check_node_footer() failed. Thanks, > + folio_end_read(folio, uptodate); > } > > if (ctx) > @@ -2887,8 +2892,15 @@ static int f2fs_read_data_large_folio(struct inode *inode, > ffs = NULL; > nrpages = folio_nr_pages(folio); > > - for (; nrpages; nrpages--, max_nr_pages--, index++, offset++) { > + for (; nrpages; > + nrpages -= len_blks, max_nr_pages -= len_blks, > + index += len_blks, offset += len_blks) { > sector_t block_nr; > + bool whole_folio_in_bio; > + unsigned int i; > + > + len_blks = 1; > + > /* > * Map blocks using the previous result first. > */ > @@ -2917,13 +2929,31 @@ static int f2fs_read_data_large_folio(struct inode *inode, > got_it: > if ((map.m_flags & F2FS_MAP_MAPPED)) { > block_nr = map.m_pblk + index - map.m_lblk; > - if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), block_nr, > + > + len_blks = min_t(unsigned int, nrpages, max_nr_pages); > + len_blks = min_t(unsigned int, len_blks, > + (unsigned int)(map.m_lblk + map.m_len - index)); > + > + for (i = 0; i < len_blks; i++) { > + if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), > + block_nr + i, > DATA_GENERIC_ENHANCE_READ)) { > - ret = -EFSCORRUPTED; > - goto err_out; > + ret = -EFSCORRUPTED; > + goto err_out; > + } > } > + > + /* > + * If an entire folio is added to one bio, > + * folio_end_read() can complete the folio read status > + * without relying on f2fs_folio_state. > + */ > + whole_folio_in_bio = offset == 0 && > + len_blks == folio_nr_pages(folio); > + > } else { > size_t page_offset = offset << PAGE_SHIFT; > + > folio_zero_range(folio, page_offset, PAGE_SIZE); > if (vi && !fsverity_verify_blocks(vi, folio, PAGE_SIZE, page_offset)) { > ret = -EIO; > @@ -2933,14 +2963,14 @@ static int f2fs_read_data_large_folio(struct inode *inode, > } > > /* We must increment read_pages_pending before possible BIOs submitting > - * to prevent from premature folio_end_read() call on folio > + * to prevent from premature folio_end_read() call on folio. > */ > - if (folio_test_large(folio)) { > + if (folio_test_large(folio) && !whole_folio_in_bio) { > ffs = f2fs_ffs_find_or_alloc(folio); > > /* set the bitmap to wait */ > spin_lock_irq(&ffs->state_lock); > - ffs->read_pages_pending++; > + ffs->read_pages_pending += len_blks; > spin_unlock_irq(&ffs->state_lock); > } > > @@ -2965,17 +2995,19 @@ static int f2fs_read_data_large_folio(struct inode *inode, > * If the page is under writeback, we need to wait for > * its completion to see the correct decrypted data. > */ > - f2fs_wait_on_block_writeback(inode, block_nr); > + for (i = 0; i < len_blks; i++) > + f2fs_wait_on_block_writeback(inode, block_nr + i); > > - if (!bio_add_folio(bio, folio, F2FS_BLKSIZE, > + if (!bio_add_folio(bio, folio, len_blks * F2FS_BLKSIZE, > offset << PAGE_SHIFT)) > goto submit_and_realloc; > > folio_in_bio = true; > - inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA); > + for (i = 0; i < len_blks; i++) > + inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA); > f2fs_update_iostat(F2FS_I_SB(inode), NULL, FS_DATA_READ_IO, > - F2FS_BLKSIZE); > - last_block_in_bio = block_nr; > + len_blks * F2FS_BLKSIZE); > + last_block_in_bio = block_nr + len_blks - 1; > } > trace_f2fs_read_folio(folio, DATA); > err_out: