page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to
the radix_tree_root. Rename the address_space ->page_tree to ->i_pages,
since we don't really care that it's a tree.
[willy@infradead.org: fix nds32, fs/dax.c]
Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 586f312..5c1a327 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2099,7 +2099,8 @@ void __init page_writeback_init(void)
* so that it can tag pages faster than a dirtying process can create them).
*/
/*
- * We tag pages in batches of WRITEBACK_TAG_BATCH to reduce tree_lock latency.
+ * We tag pages in batches of WRITEBACK_TAG_BATCH to reduce the i_pages lock
+ * latency.
*/
void tag_pages_for_writeback(struct address_space *mapping,
pgoff_t start, pgoff_t end)
@@ -2109,22 +2110,22 @@ void tag_pages_for_writeback(struct address_space *mapping,
struct radix_tree_iter iter;
void **slot;
- spin_lock_irq(&mapping->tree_lock);
- radix_tree_for_each_tagged(slot, &mapping->page_tree, &iter, start,
+ xa_lock_irq(&mapping->i_pages);
+ radix_tree_for_each_tagged(slot, &mapping->i_pages, &iter, start,
PAGECACHE_TAG_DIRTY) {
if (iter.index > end)
break;
- radix_tree_iter_tag_set(&mapping->page_tree, &iter,
+ radix_tree_iter_tag_set(&mapping->i_pages, &iter,
PAGECACHE_TAG_TOWRITE);
tagged++;
if ((tagged % WRITEBACK_TAG_BATCH) != 0)
continue;
slot = radix_tree_iter_resume(slot, &iter);
- spin_unlock_irq(&mapping->tree_lock);
+ xa_unlock_irq(&mapping->i_pages);
cond_resched();
- spin_lock_irq(&mapping->tree_lock);
+ xa_lock_irq(&mapping->i_pages);
}
- spin_unlock_irq(&mapping->tree_lock);
+ xa_unlock_irq(&mapping->i_pages);
}
EXPORT_SYMBOL(tag_pages_for_writeback);
@@ -2467,13 +2468,13 @@ int __set_page_dirty_nobuffers(struct page *page)
return 1;
}
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ xa_lock_irqsave(&mapping->i_pages, flags);
BUG_ON(page_mapping(page) != mapping);
WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
account_page_dirtied(page, mapping);
- radix_tree_tag_set(&mapping->page_tree, page_index(page),
+ radix_tree_tag_set(&mapping->i_pages, page_index(page),
PAGECACHE_TAG_DIRTY);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ xa_unlock_irqrestore(&mapping->i_pages, flags);
unlock_page_memcg(page);
if (mapping->host) {
@@ -2718,11 +2719,10 @@ int test_clear_page_writeback(struct page *page)
struct backing_dev_info *bdi = inode_to_bdi(inode);
unsigned long flags;
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ xa_lock_irqsave(&mapping->i_pages, flags);
ret = TestClearPageWriteback(page);
if (ret) {
- radix_tree_tag_clear(&mapping->page_tree,
- page_index(page),
+ radix_tree_tag_clear(&mapping->i_pages, page_index(page),
PAGECACHE_TAG_WRITEBACK);
if (bdi_cap_account_writeback(bdi)) {
struct bdi_writeback *wb = inode_to_wb(inode);
@@ -2736,7 +2736,7 @@ int test_clear_page_writeback(struct page *page)
PAGECACHE_TAG_WRITEBACK))
sb_clear_inode_writeback(mapping->host);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ xa_unlock_irqrestore(&mapping->i_pages, flags);
} else {
ret = TestClearPageWriteback(page);
}
@@ -2766,7 +2766,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
struct backing_dev_info *bdi = inode_to_bdi(inode);
unsigned long flags;
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ xa_lock_irqsave(&mapping->i_pages, flags);
ret = TestSetPageWriteback(page);
if (!ret) {
bool on_wblist;
@@ -2774,8 +2774,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
on_wblist = mapping_tagged(mapping,
PAGECACHE_TAG_WRITEBACK);
- radix_tree_tag_set(&mapping->page_tree,
- page_index(page),
+ radix_tree_tag_set(&mapping->i_pages, page_index(page),
PAGECACHE_TAG_WRITEBACK);
if (bdi_cap_account_writeback(bdi))
inc_wb_stat(inode_to_wb(inode), WB_WRITEBACK);
@@ -2789,14 +2788,12 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
sb_mark_inode_writeback(mapping->host);
}
if (!PageDirty(page))
- radix_tree_tag_clear(&mapping->page_tree,
- page_index(page),
+ radix_tree_tag_clear(&mapping->i_pages, page_index(page),
PAGECACHE_TAG_DIRTY);
if (!keep_write)
- radix_tree_tag_clear(&mapping->page_tree,
- page_index(page),
+ radix_tree_tag_clear(&mapping->i_pages, page_index(page),
PAGECACHE_TAG_TOWRITE);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ xa_unlock_irqrestore(&mapping->i_pages, flags);
} else {
ret = TestSetPageWriteback(page);
}
@@ -2816,7 +2813,7 @@ EXPORT_SYMBOL(__test_set_page_writeback);
*/
int mapping_tagged(struct address_space *mapping, int tag)
{
- return radix_tree_tagged(&mapping->page_tree, tag);
+ return radix_tree_tagged(&mapping->i_pages, tag);
}
EXPORT_SYMBOL(mapping_tagged);
