From: Matthew Wilcox <willy@infradead.org>
To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org
Cc: Matthew Wilcox <mawilcox@microsoft.com>, Jan Kara <jack@suse.cz>,
Jeff Layton <jlayton@redhat.com>,
Lukas Czerner <lczerner@redhat.com>,
Ross Zwisler <ross.zwisler@linux.intel.com>,
Christoph Hellwig <hch@lst.de>,
Goldwyn Rodrigues <rgoldwyn@suse.com>,
Nicholas Piggin <npiggin@gmail.com>,
Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>,
linux-nilfs@vger.kernel.org, Jaegeuk Kim <jaegeuk@kernel.org>,
Chao Yu <yuchao0@huawei.com>,
linux-f2fs-devel@lists.sourceforge.net
Subject: [PATCH v13 23/72] page cache: Convert find_get_entry to XArray
Date: Mon, 11 Jun 2018 07:05:50 -0700 [thread overview]
Message-ID: <20180611140639.17215-24-willy@infradead.org> (raw)
In-Reply-To: <20180611140639.17215-1-willy@infradead.org>
From: Matthew Wilcox <mawilcox@microsoft.com>
Slightly shorter and simpler code.
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
---
mm/filemap.c | 63 +++++++++++++++++++++++-----------------------------
1 file changed, 28 insertions(+), 35 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 7cdb1d4b8117..6db3d35ff5f6 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1382,47 +1382,40 @@ EXPORT_SYMBOL(page_cache_prev_gap);
*/
struct page *find_get_entry(struct address_space *mapping, pgoff_t offset)
{
- void **pagep;
+ XA_STATE(xas, &mapping->i_pages, offset);
struct page *head, *page;
rcu_read_lock();
repeat:
- page = NULL;
- pagep = radix_tree_lookup_slot(&mapping->i_pages, offset);
- if (pagep) {
- page = radix_tree_deref_slot(pagep);
- if (unlikely(!page))
- goto out;
- if (radix_tree_exception(page)) {
- if (radix_tree_deref_retry(page))
- goto repeat;
- /*
- * A shadow entry of a recently evicted page,
- * or a swap entry from shmem/tmpfs. Return
- * it without attempting to raise page count.
- */
- goto out;
- }
+ xas_reset(&xas);
+ page = xas_load(&xas);
+ if (xas_retry(&xas, page))
+ goto repeat;
+ /*
+ * A shadow entry of a recently evicted page, or a swap entry from
+ * shmem/tmpfs. Return it without attempting to raise page count.
+ */
+ if (!page || xa_is_value(page))
+ goto out;
- head = compound_head(page);
- if (!page_cache_get_speculative(head))
- goto repeat;
+ head = compound_head(page);
+ if (!page_cache_get_speculative(head))
+ goto repeat;
- /* The page was split under us? */
- if (compound_head(page) != head) {
- put_page(head);
- goto repeat;
- }
+ /* The page was split under us? */
+ if (compound_head(page) != head) {
+ put_page(head);
+ goto repeat;
+ }
- /*
- * Has the page moved?
- * This is part of the lockless pagecache protocol. See
- * include/linux/pagemap.h for details.
- */
- if (unlikely(page != *pagep)) {
- put_page(head);
- goto repeat;
- }
+ /*
+ * Has the page moved?
+ * This is part of the lockless pagecache protocol. See
+ * include/linux/pagemap.h for details.
+ */
+ if (unlikely(page != xas_reload(&xas))) {
+ put_page(head);
+ goto repeat;
}
out:
rcu_read_unlock();
@@ -1453,7 +1446,7 @@ struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset)
repeat:
page = find_get_entry(mapping, offset);
- if (page && !radix_tree_exception(page)) {
+ if (page && !xa_is_value(page)) {
lock_page(page);
/* Has the page been truncated? */
if (unlikely(page_mapping(page) != mapping)) {
--
2.17.1
next prev parent reply other threads:[~2018-06-11 14:05 UTC|newest]
Thread overview: 79+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-11 14:05 [PATCH v13 00/72] Convert page cache to XArray Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 01/72] radix tree test suite: Enable ubsan Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 02/72] dax: Fix use of zero page Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 03/72] xarray: Replace exceptional entries Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 04/72] xarray: Change definition of sibling entries Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 05/72] xarray: Add definition of struct xarray Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 06/72] xarray: Define struct xa_node Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 07/72] xarray: Add documentation Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 08/72] xarray: Add xa_load Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 09/72] xarray: Add XArray tags Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 10/72] xarray: Add xa_store Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 11/72] xarray: Add xa_cmpxchg and xa_insert Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 12/72] xarray: Add xa_for_each Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 13/72] xarray: Add xa_extract Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 14/72] xarray: Add xa_destroy Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 15/72] xarray: Add xas_next and xas_prev Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 16/72] xarray: Add xas_for_each_conflict Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 17/72] xarray: Add xas_create_range Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 18/72] xarray: Add MAINTAINERS entry Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 19/72] page cache: Rearrange address_space Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 20/72] page cache: Convert hole search to XArray Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 21/72] page cache: Add and replace pages using the XArray Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 22/72] page cache: Convert page deletion to XArray Matthew Wilcox
2018-06-11 14:05 ` Matthew Wilcox [this message]
2018-06-11 14:05 ` [PATCH v13 24/72] page cache: Convert find_get_entries " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 25/72] page cache: Convert find_get_pages_range " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 26/72] page cache: Convert find_get_pages_contig " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 27/72] page cache; Convert find_get_pages_range_tag " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 28/72] page cache: Convert find_get_entries_tag " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 29/72] page cache: Convert filemap_map_pages " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 30/72] radix tree test suite: Convert regression1 " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 31/72] page cache: Convert delete_batch " Matthew Wilcox
2018-06-11 14:05 ` [PATCH v13 32/72] page cache: Remove stray radix comment Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 33/72] page cache: Convert filemap_range_has_page to XArray Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 34/72] mm: Convert page-writeback " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 35/72] mm: Convert workingset " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 36/72] mm: Convert truncate " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 37/72] mm: Convert add_to_swap_cache " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 38/72] mm: Convert delete_from_swap_cache " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 39/72] mm: Convert __do_page_cache_readahead " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 40/72] mm: Convert page migration " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 41/72] mm: Convert huge_memory " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 42/72] mm: Convert collapse_shmem " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 43/72] mm: Convert khugepaged_scan_shmem " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 44/72] mm: Convert is_page_cache_freeable " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 45/72] pagevec: Use xa_tag_t Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 46/72] shmem: Convert shmem_radix_tree_replace to XArray Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 47/72] shmem: Convert shmem_confirm_swap " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 48/72] shmem: Convert find_swap_entry " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 49/72] shmem: Convert shmem_add_to_page_cache " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 50/72] shmem: Convert shmem_alloc_hugepage " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 51/72] shmem: Convert shmem_free_swap " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 52/72] shmem: Convert shmem_partial_swap_usage " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 53/72] memfd: Convert memfd_wait_for_pins " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 54/72] memfd: Convert memfd_tag_pins " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 55/72] shmem: Comment fixups Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 56/72] btrfs: Convert page cache to XArray Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 57/72] fs: Convert buffer " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 58/72] fs: Convert writeback " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 59/72] nilfs2: Convert " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 60/72] f2fs: " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 61/72] dax: Rename some functions Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 62/72] dax: Hash on XArray instead of mapping Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 63/72] dax: Convert dax_insert_pfn_mkwrite to XArray Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 64/72] dax: Convert dax_layout_busy_page " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 65/72] dax: Convert __dax_invalidate_entry " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 66/72] dax: Convert dax writeback " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 67/72] dax: Convert page fault handlers " Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 68/72] page cache: Finish XArray conversion Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 69/72] radix tree: Remove radix_tree_update_node_t Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 70/72] radix tree: Remove split/join code Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 71/72] radix tree: Remove radix_tree_maybe_preload_order Matthew Wilcox
2018-06-11 14:06 ` [PATCH v13 72/72] radix tree: Remove radix_tree_clear_tags Matthew Wilcox
2018-06-12 10:40 ` [PATCH v13 00/72] Convert page cache to XArray David Sterba
2018-06-12 11:31 ` Matthew Wilcox
2018-06-12 19:37 ` Ross Zwisler
2018-06-12 19:46 ` Matthew Wilcox
2018-06-13 20:10 ` Ross Zwisler
2018-06-16 12:07 ` Matthew Wilcox
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180611140639.17215-24-willy@infradead.org \
--to=willy@infradead.org \
--cc=hch@lst.de \
--cc=jack@suse.cz \
--cc=jaegeuk@kernel.org \
--cc=jlayton@redhat.com \
--cc=konishi.ryusuke@lab.ntt.co.jp \
--cc=lczerner@redhat.com \
--cc=linux-f2fs-devel@lists.sourceforge.net \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nilfs@vger.kernel.org \
--cc=mawilcox@microsoft.com \
--cc=npiggin@gmail.com \
--cc=rgoldwyn@suse.com \
--cc=ross.zwisler@linux.intel.com \
--cc=yuchao0@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).