| Message ID | 20210715033704.692967-106-willy@infradead.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Memory folios | expand |
On Thu, Jul 15, 2021 at 04:36:31AM +0100, Matthew Wilcox (Oracle) wrote: > We still iterate one block at a time, but now we call compound_head() > less often. Rename file_offset to pos to fit the rest of the file. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > --- > fs/iomap/buffered-io.c | 66 +++++++++++++++++++----------------------- > 1 file changed, 30 insertions(+), 36 deletions(-) > > diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c > index ac33f19325ab..8e767aec8d07 100644 > --- a/fs/iomap/buffered-io.c > +++ b/fs/iomap/buffered-io.c > @@ -1252,36 +1252,29 @@ iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t offset, > * first, otherwise finish off the current ioend and start another. > */ > static void > -iomap_add_to_ioend(struct inode *inode, loff_t offset, struct page *page, > +iomap_add_to_ioend(struct inode *inode, loff_t pos, struct folio *folio, > struct iomap_page *iop, struct iomap_writepage_ctx *wpc, > struct writeback_control *wbc, struct list_head *iolist) > { > - sector_t sector = iomap_sector(&wpc->iomap, offset); > + sector_t sector = iomap_sector(&wpc->iomap, pos); > unsigned len = i_blocksize(inode); > - unsigned poff = offset & (PAGE_SIZE - 1); > - bool merged, same_page = false; > + size_t poff = offset_in_folio(folio, pos); > > - if (!wpc->ioend || !iomap_can_add_to_ioend(wpc, offset, sector)) { > + if (!wpc->ioend || !iomap_can_add_to_ioend(wpc, pos, sector)) { > if (wpc->ioend) > list_add(&wpc->ioend->io_list, iolist); > - wpc->ioend = iomap_alloc_ioend(inode, wpc, offset, sector, wbc); > + wpc->ioend = iomap_alloc_ioend(inode, wpc, pos, sector, wbc); > } > > - merged = __bio_try_merge_page(wpc->ioend->io_bio, page, len, poff, > - &same_page); > if (iop) > atomic_add(len, &iop->write_bytes_pending); > - > - if (!merged) { > - if (bio_full(wpc->ioend->io_bio, len)) { > - wpc->ioend->io_bio = > - iomap_chain_bio(wpc->ioend->io_bio); > - } > - bio_add_page(wpc->ioend->io_bio, page, len, poff); > + if (!bio_add_folio(wpc->ioend->io_bio, folio, len, poff)) { > + wpc->ioend->io_bio = iomap_chain_bio(wpc->ioend->io_bio); > + bio_add_folio(wpc->ioend->io_bio, folio, len, poff); The paranoiac in me wonders if we ought to have some sort of error checking here just in case we encounter double failures? > } > > wpc->ioend->io_size += len; > - wbc_account_cgroup_owner(wbc, page, len); > + wbc_account_cgroup_owner(wbc, &folio->page, len); > } > > /* > @@ -1309,40 +1302,41 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, > struct iomap_page *iop = to_iomap_page(folio); > struct iomap_ioend *ioend, *next; > unsigned len = i_blocksize(inode); > - u64 file_offset; /* file offset of page */ > + unsigned nblocks = i_blocks_per_folio(inode, folio); > + loff_t pos = folio_pos(folio); > int error = 0, count = 0, i; > LIST_HEAD(submit_list); > > - WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop); > + WARN_ON_ONCE(nblocks > 1 && !iop); > WARN_ON_ONCE(iop && atomic_read(&iop->write_bytes_pending) != 0); > > /* > - * Walk through the page to find areas to write back. If we run off the > - * end of the current map or find the current map invalid, grab a new > - * one. > + * Walk through the folio to find areas to write back. If we > + * run off the end of the current map or find the current map > + * invalid, grab a new one. > */ > - for (i = 0, file_offset = page_offset(page); > - i < (PAGE_SIZE >> inode->i_blkbits) && file_offset < end_offset; > - i++, file_offset += len) { > + for (i = 0; i < nblocks; i++, pos += len) { > + if (pos >= end_offset) > + break; Any particular reason this isn't: for (i = 0; i < nblocks && pos < end_offset; i++, pos += len) { ? Everything from here on out looks decent to me. --D > if (iop && !test_bit(i, iop->uptodate)) > continue; > > - error = wpc->ops->map_blocks(wpc, inode, file_offset); > + error = wpc->ops->map_blocks(wpc, inode, pos); > if (error) > break; > if (WARN_ON_ONCE(wpc->iomap.type == IOMAP_INLINE)) > continue; > if (wpc->iomap.type == IOMAP_HOLE) > continue; > - iomap_add_to_ioend(inode, file_offset, page, iop, wpc, wbc, > + iomap_add_to_ioend(inode, pos, folio, iop, wpc, wbc, > &submit_list); > count++; > } > > WARN_ON_ONCE(!wpc->ioend && !list_empty(&submit_list)); > - WARN_ON_ONCE(!PageLocked(page)); > - WARN_ON_ONCE(PageWriteback(page)); > - WARN_ON_ONCE(PageDirty(page)); > + WARN_ON_ONCE(!folio_test_locked(folio)); > + WARN_ON_ONCE(folio_test_writeback(folio)); > + WARN_ON_ONCE(folio_test_dirty(folio)); > > /* > * We cannot cancel the ioend directly here on error. We may have > @@ -1358,16 +1352,16 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, > * now. > */ > if (wpc->ops->discard_page) > - wpc->ops->discard_page(page, file_offset); > + wpc->ops->discard_page(&folio->page, pos); > if (!count) { > - ClearPageUptodate(page); > - unlock_page(page); > + folio_clear_uptodate(folio); > + folio_unlock(folio); > goto done; > } > } > > - set_page_writeback(page); > - unlock_page(page); > + folio_start_writeback(folio); > + folio_unlock(folio); > > /* > * Preserve the original error if there was one, otherwise catch > @@ -1388,9 +1382,9 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, > * with a partial page truncate on a sub-page block sized filesystem. > */ > if (!count) > - end_page_writeback(page); > + folio_end_writeback(folio); > done: > - mapping_set_error(page->mapping, error); > + mapping_set_error(folio->mapping, error); > return error; > } > > -- > 2.30.2 >
On Thu, Jul 15, 2021 at 03:01:20PM -0700, Darrick J. Wong wrote: > On Thu, Jul 15, 2021 at 04:36:31AM +0100, Matthew Wilcox (Oracle) wrote: > > > > - merged = __bio_try_merge_page(wpc->ioend->io_bio, page, len, poff, > > - &same_page); > > if (iop) > > atomic_add(len, &iop->write_bytes_pending); > > - > > - if (!merged) { > > - if (bio_full(wpc->ioend->io_bio, len)) { > > - wpc->ioend->io_bio = > > - iomap_chain_bio(wpc->ioend->io_bio); > > - } > > - bio_add_page(wpc->ioend->io_bio, page, len, poff); > > + if (!bio_add_folio(wpc->ioend->io_bio, folio, len, poff)) { > > + wpc->ioend->io_bio = iomap_chain_bio(wpc->ioend->io_bio); > > + bio_add_folio(wpc->ioend->io_bio, folio, len, poff); > > The paranoiac in me wonders if we ought to have some sort of error > checking here just in case we encounter double failures? Maybe? We didn't have it before, and it's just been allocated. I'd defer to Christoph here. > > - for (i = 0, file_offset = page_offset(page); > > - i < (PAGE_SIZE >> inode->i_blkbits) && file_offset < end_offset; > > - i++, file_offset += len) { > > + for (i = 0; i < nblocks; i++, pos += len) { > > + if (pos >= end_offset) > > + break; > > Any particular reason this isn't: > > for (i = 0; i < nblocks && pos < end_offset; i++, pos += len) { > > ? Just mild personal preference ... I don't even like having the pos += len in there. But you're maintainer, I'll shuffle that in. > Everything from here on out looks decent to me. Thanks!
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index ac33f19325ab..8e767aec8d07 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1252,36 +1252,29 @@ iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t offset, * first, otherwise finish off the current ioend and start another. */ static void -iomap_add_to_ioend(struct inode *inode, loff_t offset, struct page *page, +iomap_add_to_ioend(struct inode *inode, loff_t pos, struct folio *folio, struct iomap_page *iop, struct iomap_writepage_ctx *wpc, struct writeback_control *wbc, struct list_head *iolist) { - sector_t sector = iomap_sector(&wpc->iomap, offset); + sector_t sector = iomap_sector(&wpc->iomap, pos); unsigned len = i_blocksize(inode); - unsigned poff = offset & (PAGE_SIZE - 1); - bool merged, same_page = false; + size_t poff = offset_in_folio(folio, pos); - if (!wpc->ioend || !iomap_can_add_to_ioend(wpc, offset, sector)) { + if (!wpc->ioend || !iomap_can_add_to_ioend(wpc, pos, sector)) { if (wpc->ioend) list_add(&wpc->ioend->io_list, iolist); - wpc->ioend = iomap_alloc_ioend(inode, wpc, offset, sector, wbc); + wpc->ioend = iomap_alloc_ioend(inode, wpc, pos, sector, wbc); } - merged = __bio_try_merge_page(wpc->ioend->io_bio, page, len, poff, - &same_page); if (iop) atomic_add(len, &iop->write_bytes_pending); - - if (!merged) { - if (bio_full(wpc->ioend->io_bio, len)) { - wpc->ioend->io_bio = - iomap_chain_bio(wpc->ioend->io_bio); - } - bio_add_page(wpc->ioend->io_bio, page, len, poff); + if (!bio_add_folio(wpc->ioend->io_bio, folio, len, poff)) { + wpc->ioend->io_bio = iomap_chain_bio(wpc->ioend->io_bio); + bio_add_folio(wpc->ioend->io_bio, folio, len, poff); } wpc->ioend->io_size += len; - wbc_account_cgroup_owner(wbc, page, len); + wbc_account_cgroup_owner(wbc, &folio->page, len); } /* @@ -1309,40 +1302,41 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, struct iomap_page *iop = to_iomap_page(folio); struct iomap_ioend *ioend, *next; unsigned len = i_blocksize(inode); - u64 file_offset; /* file offset of page */ + unsigned nblocks = i_blocks_per_folio(inode, folio); + loff_t pos = folio_pos(folio); int error = 0, count = 0, i; LIST_HEAD(submit_list); - WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop); + WARN_ON_ONCE(nblocks > 1 && !iop); WARN_ON_ONCE(iop && atomic_read(&iop->write_bytes_pending) != 0); /* - * Walk through the page to find areas to write back. If we run off the - * end of the current map or find the current map invalid, grab a new - * one. + * Walk through the folio to find areas to write back. If we + * run off the end of the current map or find the current map + * invalid, grab a new one. */ - for (i = 0, file_offset = page_offset(page); - i < (PAGE_SIZE >> inode->i_blkbits) && file_offset < end_offset; - i++, file_offset += len) { + for (i = 0; i < nblocks; i++, pos += len) { + if (pos >= end_offset) + break; if (iop && !test_bit(i, iop->uptodate)) continue; - error = wpc->ops->map_blocks(wpc, inode, file_offset); + error = wpc->ops->map_blocks(wpc, inode, pos); if (error) break; if (WARN_ON_ONCE(wpc->iomap.type == IOMAP_INLINE)) continue; if (wpc->iomap.type == IOMAP_HOLE) continue; - iomap_add_to_ioend(inode, file_offset, page, iop, wpc, wbc, + iomap_add_to_ioend(inode, pos, folio, iop, wpc, wbc, &submit_list); count++; } WARN_ON_ONCE(!wpc->ioend && !list_empty(&submit_list)); - WARN_ON_ONCE(!PageLocked(page)); - WARN_ON_ONCE(PageWriteback(page)); - WARN_ON_ONCE(PageDirty(page)); + WARN_ON_ONCE(!folio_test_locked(folio)); + WARN_ON_ONCE(folio_test_writeback(folio)); + WARN_ON_ONCE(folio_test_dirty(folio)); /* * We cannot cancel the ioend directly here on error. We may have @@ -1358,16 +1352,16 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, * now. */ if (wpc->ops->discard_page) - wpc->ops->discard_page(page, file_offset); + wpc->ops->discard_page(&folio->page, pos); if (!count) { - ClearPageUptodate(page); - unlock_page(page); + folio_clear_uptodate(folio); + folio_unlock(folio); goto done; } } - set_page_writeback(page); - unlock_page(page); + folio_start_writeback(folio); + folio_unlock(folio); /* * Preserve the original error if there was one, otherwise catch @@ -1388,9 +1382,9 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, * with a partial page truncate on a sub-page block sized filesystem. */ if (!count) - end_page_writeback(page); + folio_end_writeback(folio); done: - mapping_set_error(page->mapping, error); + mapping_set_error(folio->mapping, error); return error; }
We still iterate one block at a time, but now we call compound_head() less often. Rename file_offset to pos to fit the rest of the file. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- fs/iomap/buffered-io.c | 66 +++++++++++++++++++----------------------- 1 file changed, 30 insertions(+), 36 deletions(-)