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| author | Matthew Wilcox <willy@infradead.org> | 2017-11-03 18:30:42 +0100 |
|---|---|---|
| committer | Matthew Wilcox <willy@infradead.org> | 2018-09-30 04:47:49 +0200 |
| commit | 3159f943aafdbacb2f94c38fdaadabf2bbde2a14 (patch) | |
| tree | 7e06823a1ab7e90774535d17a217a939bdddda3b /mm/shmem.c | |
| parent | idr: Permit any valid kernel pointer to be stored (diff) | |
| download | linux-3159f943aafdbacb2f94c38fdaadabf2bbde2a14.tar.xz linux-3159f943aafdbacb2f94c38fdaadabf2bbde2a14.zip | |
xarray: Replace exceptional entries
Introduce xarray value entries and tagged pointers to replace radix
tree exceptional entries. This is a slight change in encoding to allow
the use of an extra bit (we can now store BITS_PER_LONG - 1 bits in a
value entry). It is also a change in emphasis; exceptional entries are
intimidating and different. As the comment explains, you can choose
to store values or pointers in the xarray and they are both first-class
citizens.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Diffstat (limited to 'mm/shmem.c')
| -rw-r--r-- | mm/shmem.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 446942677cd4..c1062760fe41 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -709,7 +709,7 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping, continue; } - if (radix_tree_exceptional_entry(page)) + if (xa_is_value(page)) swapped++; if (need_resched()) { @@ -824,7 +824,7 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, if (index >= end) break; - if (radix_tree_exceptional_entry(page)) { + if (xa_is_value(page)) { if (unfalloc) continue; nr_swaps_freed += !shmem_free_swap(mapping, @@ -921,7 +921,7 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, if (index >= end) break; - if (radix_tree_exceptional_entry(page)) { + if (xa_is_value(page)) { if (unfalloc) continue; if (shmem_free_swap(mapping, index, page)) { @@ -1643,7 +1643,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, repeat: swap.val = 0; page = find_lock_entry(mapping, index); - if (radix_tree_exceptional_entry(page)) { + if (xa_is_value(page)) { swap = radix_to_swp_entry(page); page = NULL; } @@ -2578,7 +2578,7 @@ static pgoff_t shmem_seek_hole_data(struct address_space *mapping, index = indices[i]; } page = pvec.pages[i]; - if (page && !radix_tree_exceptional_entry(page)) { + if (page && !xa_is_value(page)) { if (!PageUptodate(page)) page = NULL; } |