Re: [PATCH 06/15] xfs: Pass a page to xfs_finish_page_writeback

Re: [PATCH 06/15] xfs: Pass a page to xfs_finish_page_writeback

[Hillf Danton]

On Sat, 5 Oct 2019 03:35:36 +0800 Matthew Wilcox wrote:
> 
> On Thu, Oct 03, 2019 at 12:08:46PM +0800, Hillf Danton wrote:
> >
> > On Tue, 24 Sep 2019 17:52:02 -0700 From: Matthew Wilcox (Oracle)
> > >
> > > The only part of the bvec we were accessing was the bv_page, so just
> > > pass that instead of the whole bvec.
> >
> > Change is added in ABI without a bit of win.
> > Changes like this are not needed.
> 
> ABI?  This is a static function.  The original recommendation to do this
> came from Christoph, who I would trust over you as a referee of what
> changes to make to XFS.

Hehe, I try to see your point, nice code will never be able to
escape standing ovation.

[RFC 00/15] Large pages in the page-cache

[Matthew Wilcox]

From: "Matthew Wilcox (Oracle)" <willy@infradead.org>

Here's what I'm currently playing with.  I'm having trouble _testing_
it, but since akpm's patches were just merged into Linus' tree, I
thought this would be a good point to send out my current work tree.
Thanks to kbuild bot for finding a bunch of build problems ;-)

Matthew Wilcox (Oracle) (12):
  mm: Use vm_fault error code directly
  fs: Introduce i_blocks_per_page
  mm: Add file_offset_of_ helpers
  iomap: Support large pages
  xfs: Support large pages
  xfs: Pass a page to xfs_finish_page_writeback
  mm: Make prep_transhuge_page tail-callable
  mm: Add __page_cache_alloc_order
  mm: Allow large pages to be added to the page cache
  mm: Allow find_get_page to be used for large pages
  mm: Remove hpage_nr_pages
  xfs: Use filemap_huge_fault

William Kucharski (3):
  mm: Support removing arbitrary sized pages from mapping
  mm: Add a huge page fault handler for files
  mm: Align THP mappings for non-DAX

 drivers/net/ethernet/ibm/ibmveth.c |   2 -
 drivers/nvdimm/btt.c               |   4 +-
 drivers/nvdimm/pmem.c              |   3 +-
 fs/iomap/buffered-io.c             | 121 +++++++----
 fs/jfs/jfs_metapage.c              |   2 +-
 fs/xfs/xfs_aops.c                  |  37 ++--
 fs/xfs/xfs_file.c                  |   5 +-
 include/linux/huge_mm.h            |  15 +-
 include/linux/iomap.h              |   2 +-
 include/linux/mm.h                 |  12 ++
 include/linux/mm_inline.h          |   6 +-
 include/linux/pagemap.h            |  73 ++++++-
 mm/filemap.c                       | 311 ++++++++++++++++++++++++++---
 mm/gup.c                           |   2 +-
 mm/huge_memory.c                   |  11 +-
 mm/internal.h                      |   4 +-
 mm/memcontrol.c                    |  14 +-
 mm/memory_hotplug.c                |   4 +-
 mm/mempolicy.c                     |   2 +-
 mm/migrate.c                       |  19 +-
 mm/mlock.c                         |   9 +-
 mm/page_io.c                       |   4 +-
 mm/page_vma_mapped.c               |   6 +-
 mm/rmap.c                          |   8 +-
 mm/swap.c                          |   4 +-
 mm/swap_state.c                    |   4 +-
 mm/swapfile.c                      |   2 +-
 mm/vmscan.c                        |   9 +-
 28 files changed, 519 insertions(+), 176 deletions(-)

-- 
2.23.0

[PATCH 06/15] xfs: Pass a page to xfs_finish_page_writeback

[Matthew Wilcox]

From: "Matthew Wilcox (Oracle)" <willy@infradead.org>

The only part of the bvec we were accessing was the bv_page, so just
pass that instead of the whole bvec.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 fs/xfs/xfs_aops.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 1a26e9ca626b..edcb4797fcc2 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -58,21 +58,21 @@ xfs_find_daxdev_for_inode(
 static void
 xfs_finish_page_writeback(
 	struct inode		*inode,
-	struct bio_vec	*bvec,
+	struct page		*page,
 	int			error)
 {
-	struct iomap_page	*iop = to_iomap_page(bvec->bv_page);
+	struct iomap_page	*iop = to_iomap_page(page);
 
 	if (error) {
-		SetPageError(bvec->bv_page);
+		SetPageError(page);
 		mapping_set_error(inode->i_mapping, -EIO);
 	}
 
-	ASSERT(iop || i_blocks_per_page(inode, bvec->bv_page) <= 1);
+	ASSERT(iop || i_blocks_per_page(inode, page) <= 1);
 	ASSERT(!iop || atomic_read(&iop->write_count) > 0);
 
 	if (!iop || atomic_dec_and_test(&iop->write_count))
-		end_page_writeback(bvec->bv_page);
+		end_page_writeback(page);
 }
 
 /*
@@ -106,7 +106,7 @@ xfs_destroy_ioend(
 
 		/* walk each page on bio, ending page IO on them */
 		bio_for_each_segment_all(bvec, bio, iter_all)
-			xfs_finish_page_writeback(inode, bvec, error);
+			xfs_finish_page_writeback(inode, bvec->bv_page, error);
 		bio_put(bio);
 	}
 
-- 
2.23.0

Re: [PATCH 06/15] xfs: Pass a page to xfs_finish_page_writeback

[Hillf Danton]

On Tue, 24 Sep 2019 17:52:02 -0700 From: Matthew Wilcox (Oracle)
> 
> The only part of the bvec we were accessing was the bv_page, so just
> pass that instead of the whole bvec.

Change is added in ABI without a bit of win.
Changes like this are not needed.

Re: [PATCH 06/15] xfs: Pass a page to xfs_finish_page_writeback

[Matthew Wilcox]

On Thu, Oct 03, 2019 at 12:08:46PM +0800, Hillf Danton wrote:
> 
> On Tue, 24 Sep 2019 17:52:02 -0700 From: Matthew Wilcox (Oracle)
> > 
> > The only part of the bvec we were accessing was the bv_page, so just
> > pass that instead of the whole bvec.
> 
> Change is added in ABI without a bit of win.
> Changes like this are not needed.

ABI?  This is a static function.  The original recommendation to do this
came from Christoph, who I would trust over you as a referee of what
changes to make to XFS.