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 83BB4C7EE23 for ; Mon, 5 Jun 2023 22:54:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232112AbjFEWyi (ORCPT ); Mon, 5 Jun 2023 18:54:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230447AbjFEWyh (ORCPT ); Mon, 5 Jun 2023 18:54:37 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C2CE98; Mon, 5 Jun 2023 15:54:36 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id F405F62B8C; Mon, 5 Jun 2023 22:54:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FE66C433EF; Mon, 5 Jun 2023 22:54:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686005675; bh=MUh0/+DEO3vwushbZitrLhkvZGGM1ubSW+hXZsJy8qY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=d7LTVzSKsBxpYKSEnftji3hvzEeKhOu1KeOQgmXIgs9AddybiwrJmbw4ahY2LNo2E KCsK8vB9UqTItTD+MTAG3nrBngoQLOW/slk+baDbYBBDZqXt0wiuHo/G9wQHENmy2j qMfEM2VSI49vXv0/VqgEuOcu7D9NcyabfdVh377Fw1oHAgSDibGVj4Id7ItzkyyLeM BIANqAAP/n7QBAYOF4N6162y2Ci0r89LQKYnoL121t6VSaw8hjZa7urGl5PKQZmigM TY5pFQvCzuHZLdxE75kfnT8KjqajxWmH3JwV39hjvO/3XdGo7R6g8uNvCkItm2b90a XJjG3zUhHHOwg== Date: Mon, 5 Jun 2023 15:54:34 -0700 From: "Darrick J. Wong" To: "Ritesh Harjani (IBM)" Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Matthew Wilcox , Dave Chinner , Brian Foster , Christoph Hellwig , Andreas Gruenbacher , Ojaswin Mujoo , Disha Goel Subject: Re: [PATCHv7 3/6] iomap: Refactor some iop related accessor functions Message-ID: <20230605225434.GF1325469@frogsfrogsfrogs> References: <4fe4937718d44c89e0c279175c65921717d9f591.1685962158.git.ritesh.list@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4fe4937718d44c89e0c279175c65921717d9f591.1685962158.git.ritesh.list@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Mon, Jun 05, 2023 at 04:25:03PM +0530, Ritesh Harjani (IBM) wrote: > We would eventually use iomap_iop_** function naming by the rest of the > buffered-io iomap code. This patch update function arguments and naming > from iomap_set_range_uptodate() -> iomap_iop_set_range_uptodate(). > iop_set_range_uptodate() then becomes an accessor function used by > iomap_iop_** functions. > > Signed-off-by: Ritesh Harjani (IBM) > --- > fs/iomap/buffered-io.c | 111 +++++++++++++++++++++++------------------ > 1 file changed, 63 insertions(+), 48 deletions(-) > > diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c > index 6fffda355c45..136f57ccd0be 100644 > --- a/fs/iomap/buffered-io.c > +++ b/fs/iomap/buffered-io.c > @@ -24,14 +24,14 @@ > #define IOEND_BATCH_SIZE 4096 > > /* > - * Structure allocated for each folio when block size < folio size > - * to track sub-folio uptodate status and I/O completions. > + * Structure allocated for each folio to track per-block uptodate state > + * 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; > + unsigned long state[]; > }; > > static inline struct iomap_page *to_iomap_page(struct folio *folio) > @@ -43,6 +43,48 @@ static inline struct iomap_page *to_iomap_page(struct folio *folio) > > static struct bio_set iomap_ioend_bioset; > > +static bool iop_test_full_uptodate(struct folio *folio) Same comment as Andreas, I think this works better with 'fully', e.g. iop_test_fully_uptodate() Why you don't pass the iomap_page directly into this function? Doesn't that eliminate the need for iomap_iop_free to keep folio->private set until the very end? static inline bool iomap_iop_is_fully_uptodate(const struct iomap_page *iop, const struct folio *folio) Same sort of thing for the second function -- we already extracted folio->private and checked it wasn't null, so we don't need to do that again. static inline bool iomap_io_is_block_uptodate(const struct iomap_page *iop, const struct folio *folio, unsigned int block) > +{ > + struct iomap_page *iop = to_iomap_page(folio); > + struct inode *inode = folio->mapping->host; > + > + return bitmap_full(iop->state, i_blocks_per_folio(inode, folio)); > +} > + > +static bool iop_test_block_uptodate(struct folio *folio, unsigned int block) > +{ > + struct iomap_page *iop = to_iomap_page(folio); > + > + return test_bit(block, iop->state); > +} > + > +static void iop_set_range_uptodate(struct inode *inode, struct folio *folio, > + size_t off, size_t len) > +{ > + struct iomap_page *iop = to_iomap_page(folio); > + unsigned int first_blk = off >> inode->i_blkbits; > + unsigned int last_blk = (off + len - 1) >> inode->i_blkbits; > + unsigned int nr_blks = last_blk - first_blk + 1; > + unsigned long flags; > + > + spin_lock_irqsave(&iop->state_lock, flags); > + bitmap_set(iop->state, first_blk, nr_blks); > + if (iop_test_full_uptodate(folio)) > + folio_mark_uptodate(folio); > + spin_unlock_irqrestore(&iop->state_lock, flags); > +} > + > +static void iomap_iop_set_range_uptodate(struct inode *inode, I don't understand why iomap_set_range_uptodate is now iomap_iop_set_range_uptodate; it doesn't take an iomap_page object as an argument...? I thought I understood that iomap_FOO operates on a folio and a range, whereas iomap_iop_FOO operates on sub-blocks within a folio? And that you were renaming the iop_* functions to iomap_iop_*? I'm also not sure why iop_set_range_uptodate needs to be passed the struct inode; can't it extract that from folio->mapping->host, like current upstream does? Generally I don't understand why this part of the patch is needed at all. Wasn't the point merely to rename uptodate_* to state_* and introduce the iomap_iop_test_*_uptodate helpers? --D > + struct folio *folio, size_t off, size_t len) > +{ > + struct iomap_page *iop = to_iomap_page(folio); > + > + if (iop) > + iop_set_range_uptodate(inode, folio, off, len); > + else > + folio_mark_uptodate(folio); > +} > + > static struct iomap_page *iomap_iop_alloc(struct inode *inode, > struct folio *folio, unsigned int flags) > { > @@ -58,12 +100,12 @@ static struct iomap_page *iomap_iop_alloc(struct inode *inode, > else > gfp = GFP_NOFS | __GFP_NOFAIL; > > - iop = kzalloc(struct_size(iop, uptodate, BITS_TO_LONGS(nr_blocks)), > + iop = kzalloc(struct_size(iop, state, BITS_TO_LONGS(nr_blocks)), > gfp); > if (iop) { > - spin_lock_init(&iop->uptodate_lock); > + spin_lock_init(&iop->state_lock); > if (folio_test_uptodate(folio)) > - bitmap_fill(iop->uptodate, nr_blocks); > + bitmap_fill(iop->state, nr_blocks); > folio_attach_private(folio, iop); > } > return iop; > @@ -72,14 +114,12 @@ static struct iomap_page *iomap_iop_alloc(struct inode *inode, > static void iomap_iop_free(struct folio *folio) > { > struct iomap_page *iop = to_iomap_page(folio); > - struct inode *inode = folio->mapping->host; > - unsigned int nr_blocks = i_blocks_per_folio(inode, folio); > > if (!iop) > 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(iop_test_full_uptodate(folio) != > folio_test_uptodate(folio)); > folio_detach_private(folio); > kfree(iop); > @@ -111,7 +151,7 @@ static void iomap_adjust_read_range(struct inode *inode, struct folio *folio, > > /* move forward for each leading block marked uptodate */ > for (i = first; i <= last; i++) { > - if (!test_bit(i, iop->uptodate)) > + if (!iop_test_block_uptodate(folio, i)) > break; > *pos += block_size; > poff += block_size; > @@ -121,7 +161,7 @@ static void iomap_adjust_read_range(struct inode *inode, struct folio *folio, > > /* truncate len if we find any trailing uptodate block(s) */ > for ( ; i <= last; i++) { > - if (test_bit(i, iop->uptodate)) { > + if (iop_test_block_uptodate(folio, i)) { > plen -= (last - i + 1) * block_size; > last = i - 1; > break; > @@ -145,30 +185,6 @@ static void iomap_adjust_read_range(struct inode *inode, struct folio *folio, > *lenp = plen; > } > > -static void iomap_iop_set_range_uptodate(struct folio *folio, > - struct iomap_page *iop, size_t off, size_t len) > -{ > - struct inode *inode = folio->mapping->host; > - unsigned first = off >> inode->i_blkbits; > - 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_folio(inode, folio))) > - folio_mark_uptodate(folio); > - spin_unlock_irqrestore(&iop->uptodate_lock, flags); > -} > - > -static void iomap_set_range_uptodate(struct folio *folio, > - struct iomap_page *iop, size_t off, size_t len) > -{ > - if (iop) > - iomap_iop_set_range_uptodate(folio, iop, off, len); > - else > - folio_mark_uptodate(folio); > -} > - > static void iomap_finish_folio_read(struct folio *folio, size_t offset, > size_t len, int error) > { > @@ -178,7 +194,8 @@ static void iomap_finish_folio_read(struct folio *folio, size_t offset, > folio_clear_uptodate(folio); > folio_set_error(folio); > } else { > - iomap_set_range_uptodate(folio, iop, offset, len); > + iomap_iop_set_range_uptodate(folio->mapping->host, folio, > + offset, len); > } > > if (!iop || atomic_sub_and_test(len, &iop->read_bytes_pending)) > @@ -214,7 +231,6 @@ struct iomap_readpage_ctx { > static int iomap_read_inline_data(const struct iomap_iter *iter, > struct folio *folio) > { > - struct iomap_page *iop; > const struct iomap *iomap = iomap_iter_srcmap(iter); > size_t size = i_size_read(iter->inode) - iomap->offset; > size_t poff = offset_in_page(iomap->offset); > @@ -232,15 +248,14 @@ static int iomap_read_inline_data(const struct iomap_iter *iter, > if (WARN_ON_ONCE(size > iomap->length)) > return -EIO; > if (offset > 0) > - iop = iomap_iop_alloc(iter->inode, folio, iter->flags); > - else > - iop = to_iomap_page(folio); > + iomap_iop_alloc(iter->inode, folio, iter->flags); > > addr = kmap_local_folio(folio, offset); > memcpy(addr, iomap->inline_data, size); > memset(addr + size, 0, PAGE_SIZE - poff - size); > kunmap_local(addr); > - iomap_set_range_uptodate(folio, iop, offset, PAGE_SIZE - poff); > + iomap_iop_set_range_uptodate(iter->inode, folio, offset, > + PAGE_SIZE - poff); > return 0; > } > > @@ -277,7 +292,7 @@ static loff_t iomap_readpage_iter(const struct iomap_iter *iter, > > if (iomap_block_needs_zeroing(iter, pos)) { > folio_zero_range(folio, poff, plen); > - iomap_set_range_uptodate(folio, iop, poff, plen); > + iomap_iop_set_range_uptodate(iter->inode, folio, poff, plen); > goto done; > } > > @@ -452,7 +467,7 @@ bool iomap_is_partially_uptodate(struct folio *folio, size_t from, size_t count) > last = (from + count - 1) >> inode->i_blkbits; > > for (i = first; i <= last; i++) > - if (!test_bit(i, iop->uptodate)) > + if (!iop_test_block_uptodate(folio, i)) > return false; > return true; > } > @@ -591,7 +606,7 @@ static int __iomap_write_begin(const struct iomap_iter *iter, loff_t pos, > if (status) > return status; > } > - iomap_set_range_uptodate(folio, iop, poff, plen); > + iomap_iop_set_range_uptodate(iter->inode, folio, poff, plen); > } while ((block_start += plen) < block_end); > > return 0; > @@ -698,7 +713,6 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, > static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len, > size_t copied, struct folio *folio) > { > - struct iomap_page *iop = to_iomap_page(folio); > flush_dcache_folio(folio); > > /* > @@ -714,7 +728,8 @@ static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len, > */ > if (unlikely(copied < len && !folio_test_uptodate(folio))) > return 0; > - iomap_set_range_uptodate(folio, iop, offset_in_folio(folio, pos), len); > + iomap_iop_set_range_uptodate(inode, folio, offset_in_folio(folio, pos), > + len); > filemap_dirty_folio(inode->i_mapping, folio); > return copied; > } > @@ -1630,7 +1645,7 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, > * invalid, grab a new one. > */ > for (i = 0; i < nblocks && pos < end_pos; i++, pos += len) { > - if (iop && !test_bit(i, iop->uptodate)) > + if (iop && !iop_test_block_uptodate(folio, i)) > continue; > > error = wpc->ops->map_blocks(wpc, inode, pos); > -- > 2.40.1 >