[PATCH v4 00/36] Large pages in the page cache

Matthew Wilcox
2020-05-15T13:17:18Z

This patch set does not pass xfstests. Test at your own risk. It is
based on the readahead rewrite which is in Andrew's tree. I've fixed a
lot of issues in the last two weeks, but generic/013 will still crash it.

The primary idea here is that a large part of the overhead in dealing
with individual pages is that there's just so darned many of them.
We would be better off dealing with fewer, larger pages, even if they
don't get to be the size necessary for the CPU to use a larger TLB entry.

v4:
- Fix thp_size typo
- Fix the iomap page_mkwrite() path to operate on the head page, even
though the vm_fault has a pointer to the tail page
- Fix iomap_finish_ioend() to use bio_for_each_thp_segment_all()
- Rework PageDoubleMap (see first two patches for details)
- Fix page_cache_delete() to handle shadow entries being stored to a THP
- Fix the assertion in pagecache_get_page() to handle tail pages
- Change PageReadahead from NO_COMPOUND to ONLY_HEAD
- Handle PageReadahead being set on head pages
- Handle total_mapcount correctly (Kirill)
- Pull the FS_LARGE_PAGES check out into mapping_large_pages()
- Fix page size assumption in truncate_cleanup_page()
- Avoid splitting large pages unnecessarily on truncate
- Disable the page cache truncation introduced as part of the read-only
THP patch set
- Call compound_head() in iomap buffered write paths -- we retrieve a
(potentially) tail page from the page cache and need to use that for
flush_dcache_page(), but we expect to operate on a head page in most
of the iomap code

Kirill A. Shutemov (1):
mm: Fix total_mapcount assumption of page size

Matthew Wilcox (Oracle) (34):
mm: Move PageDoubleMap bit
mm: Simplify PageDoubleMap with PF_SECOND policy
mm: Allow hpages to be arbitrary order
mm: Introduce thp_size
mm: Introduce thp_order
mm: Introduce offset_in_thp
fs: Add a filesystem flag for large pages
fs: Do not update nr_thps for large page mappings
fs: Introduce i_blocks_per_page
fs: Make page_mkwrite_check_truncate thp-aware
fs: Support THPs in zero_user_segments
bio: Add bio_for_each_thp_segment_all
iomap: Support arbitrarily many blocks per page
iomap: Support large pages in iomap_adjust_read_range
iomap: Support large pages in read paths
iomap: Support large pages in write paths
iomap: Inline data shouldn't see large pages
iomap: Handle tail pages in iomap_page_mkwrite
xfs: Support large pages
mm: Make prep_transhuge_page return its argument
mm: Add __page_cache_alloc_order
mm: Allow large pages to be added to the page cache
mm: Allow large pages to be removed from the page cache
mm: Remove page fault assumption of compound page size
mm: Avoid splitting large pages
mm: Fix truncation for pages of arbitrary size
mm: Support storing shadow entries for large pages
mm: Support retrieving tail pages from the page cache
mm: Support tail pages in wait_for_stable_page
mm: Add DEFINE_READAHEAD
mm: Make page_cache_readahead_unbounded take a readahead_control
mm: Make __do_page_cache_readahead take a readahead_control
mm: Allow PageReadahead to be set on head pages
mm: Add large page readahead

William Kucharski (1):
mm: Align THP mappings for non-DAX

drivers/nvdimm/btt.c | 4 +-
drivers/nvdimm/pmem.c | 6 +-
fs/ext4/verity.c | 4 +-
fs/f2fs/verity.c | 4 +-
fs/iomap/buffered-io.c | 121 +++++++++++++++++--------------
fs/jfs/jfs_metapage.c | 2 +-
fs/xfs/xfs_aops.c | 4 +-
fs/xfs/xfs_super.c | 2 +-
include/linux/bio.h | 13 ++++
include/linux/bvec.h | 23 ++++++
include/linux/fs.h | 28 +------
include/linux/highmem.h | 15 +++-
include/linux/huge_mm.h | 25 +++++--
include/linux/mm.h | 97 +++++++++++++------------
include/linux/page-flags.h | 46 ++++--------
include/linux/pagemap.h | 96 +++++++++++++++++++++---
mm/filemap.c | 87 ++++++++++++++--------
mm/highmem.c | 62 +++++++++++++++-
mm/huge_memory.c | 58 +++++++--------
mm/internal.h | 13 ++--
mm/memory.c | 7 +-
mm/page-writeback.c | 1 +
mm/page_io.c | 2 +-
mm/page_vma_mapped.c | 4 +-
mm/readahead.c | 145 ++++++++++++++++++++++++++++---------
mm/truncate.c | 6 +-
mm/vmscan.c | 5 +-
27 files changed, 565 insertions(+), 315 deletions(-)

--
2.26.2