[PATCH v4 0/3] mm, netfs, fscache: Stop read optimisation when folio removed from pagecache

[David Howells]

Hi Linus,

How about this then?

I've split the folio_has_private()/filemap_release_folio() call pair
merging into its own patch, separate from the actual bugfix and pulled out
the folio_needs_release() function into mm/internal.h and made
filemap_release_folio() use it.  I've also got rid of the bit clearances
from the network filesystem evict_inode functions as they doesn't seem to
be necessary.

I've also added an additional experimental patch to see if the pair in
shrink_folio_list() can be reduced cleanly to just the release call.  This
involves making filemap_release_folio() have a three-state return.

David

Changes:
========
ver #4)
 - Split has_private/release call pairs into own patch.
 - Moved folio_needs_release() to mm/internal.h and removed open-coded
   version from filemap_release_folio().
 - Don't need to clear AS_RELEASE_ALWAYS in ->evict_inode().
 - Added experimental patch to reduce shrink_folio_list().

ver #3)
 - Fixed mapping_clear_release_always() to use clear_bit() not set_bit().
 - Moved a '&&' to the correct line.

ver #2)
 - Rewrote entirely according to Willy's suggestion[1].

Link: https://lore.kernel.org/r/Yk9V/03wgdYi65Lb@casper.infradead.org/ [1]
Link: https://lore.kernel.org/r/164928630577.457102.8519251179327601178.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/166844174069.1124521.10890506360974169994.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/166869495238.3720468.4878151409085146764.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/1459152.1669208550@warthog.procyon.org.uk/ # v3 also
---
David Howells (3):
      mm: Merge folio_has_private()/filemap_release_folio() call pairs
      mm, netfs, fscache: Stop read optimisation when folio removed from pagecache
      mm: Make filemap_release_folio() better inform shrink_folio_list()


 fs/9p/cache.c           |  2 ++
 fs/afs/internal.h       |  2 ++
 fs/cachefiles/namei.c   |  2 ++
 fs/ceph/cache.c         |  2 ++
 fs/cifs/fscache.c       |  2 ++
 fs/splice.c             |  3 +--
 include/linux/pagemap.h | 23 ++++++++++++++++++++++-
 mm/filemap.c            | 20 +++++++++++++++-----
 mm/huge_memory.c        |  3 +--
 mm/internal.h           | 11 +++++++++++
 mm/khugepaged.c         |  3 +--
 mm/memory-failure.c     |  3 +--
 mm/migrate.c            |  3 +--
 mm/truncate.c           |  6 ++----
 mm/vmscan.c             | 34 +++++++++++++++++-----------------
 15 files changed, 82 insertions(+), 37 deletions(-)