+ fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch added to -mm tree

+ fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch added to -mm tree

[akpm]

The patch titled
     Subject: fs: do not update nr_thps for mappings which support THPs
has been added to the -mm tree.  Its filename is
     fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: fs: do not update nr_thps for mappings which support THPs

The nr_thps counter is to support THPs in the page cache when the
filesystem doesn't understand THPs.  Eventually it will be removed, but we
should still support filesystems which do not understand THPs yet.  Move
the nr_thp manipulation functions to filemap.h since they're page-cache
specific.

Link: https://lkml.kernel.org/r/20200916032717.22917-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/fs.h      |   27 ---------------------------
 include/linux/pagemap.h |   29 +++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 27 deletions(-)

--- a/include/linux/fs.h~fs-do-not-update-nr_thps-for-mappings-which-support-thps
+++ a/include/linux/fs.h
@@ -2703,33 +2703,6 @@ static inline errseq_t file_sample_sb_er
 	return errseq_sample(&file->f_path.dentry->d_sb->s_wb_err);
 }
 
-static inline int filemap_nr_thps(struct address_space *mapping)
-{
-#ifdef CONFIG_READ_ONLY_THP_FOR_FS
-	return atomic_read(&mapping->nr_thps);
-#else
-	return 0;
-#endif
-}
-
-static inline void filemap_nr_thps_inc(struct address_space *mapping)
-{
-#ifdef CONFIG_READ_ONLY_THP_FOR_FS
-	atomic_inc(&mapping->nr_thps);
-#else
-	WARN_ON_ONCE(1);
-#endif
-}
-
-static inline void filemap_nr_thps_dec(struct address_space *mapping)
-{
-#ifdef CONFIG_READ_ONLY_THP_FOR_FS
-	atomic_dec(&mapping->nr_thps);
-#else
-	WARN_ON_ONCE(1);
-#endif
-}
-
 extern int vfs_fsync_range(struct file *file, loff_t start, loff_t end,
 			   int datasync);
 extern int vfs_fsync(struct file *file, int datasync);
--- a/include/linux/pagemap.h~fs-do-not-update-nr_thps-for-mappings-which-support-thps
+++ a/include/linux/pagemap.h
@@ -125,6 +125,35 @@ static inline bool mapping_thp_support(s
 	return test_bit(AS_THP_SUPPORT, &mapping->flags);
 }
 
+static inline int filemap_nr_thps(struct address_space *mapping)
+{
+#ifdef CONFIG_READ_ONLY_THP_FOR_FS
+	return atomic_read(&mapping->nr_thps);
+#else
+	return 0;
+#endif
+}
+
+static inline void filemap_nr_thps_inc(struct address_space *mapping)
+{
+#ifdef CONFIG_READ_ONLY_THP_FOR_FS
+	if (!mapping_thp_support(mapping))
+		atomic_inc(&mapping->nr_thps);
+#else
+	WARN_ON_ONCE(1);
+#endif
+}
+
+static inline void filemap_nr_thps_dec(struct address_space *mapping)
+{
+#ifdef CONFIG_READ_ONLY_THP_FOR_FS
+	if (!mapping_thp_support(mapping))
+		atomic_dec(&mapping->nr_thps);
+#else
+	WARN_ON_ONCE(1);
+#endif
+}
+
 void release_pages(struct page **pages, int nr);
 
 /*
_

Patches currently in -mm which might be from willy@infradead.org are

mm-debug-do-not-dereference-i_ino-blindly.patch
mm-factor-find_get_incore_page-out-of-mincore_page.patch
mm-use-find_get_incore_page-in-memcontrol.patch
mm-optimise-madvise-willneed.patch
mm-optimise-madvise-willneed-fix.patch
proc-optimise-smaps-for-shmem-entries.patch
i915-use-find_lock_page-instead-of-find_lock_entry.patch
mm-convert-find_get_entry-to-return-the-head-page.patch
mm-convert-find_get_entry-to-return-the-head-page-fix.patch
mm-shmem-return-head-page-from-find_lock_entry.patch
mm-shmem-return-head-page-from-find_lock_entry-fix.patch
mm-add-find_lock_head.patch
mm-filemap-fix-filemap_map_pages-for-thp.patch
mm-account-pmd-tables-like-pte-tables.patch
mm-move-pagedoublemap-bit.patch
mm-simplify-pagedoublemap-with-pf_second-policy.patch
xarray-add-xa_get_order.patch
xarray-add-xas_split.patch
xarray-add-xas_split-fix-2.patch
mm-filemap-fix-storing-to-a-thp-shadow-entry.patch
mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
mm-memory-remove-page-fault-assumption-of-compound-page-size.patch
mm-page_owner-change-split_page_owner-to-take-a-count.patch
mm-huge_memory-fix-page_trans_huge_mapcount-assumption-of-thp-size.patch
mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch
mm-rmap-fix-assumptions-of-thp-size.patch
mm-truncate-fix-truncation-for-pages-of-arbitrary-size.patch
mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch
mm-vmscan-allow-arbitrary-sized-pages-to-be-paged-out.patch
fs-add-a-filesystem-flag-for-thps.patch
fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch
mm-readahead-add-define_readahead.patch
mm-readahead-make-page_cache_ra_unbounded-take-a-readahead_control.patch
mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
mm-readahead-add-page_cache_sync_ra-and-page_cache_async_ra.patch
harden-autofs-ioctl-table.patch