ceph: use vfs __set_page_dirty_nobuffers interface instead of doing it inside filesystem (7d6e1f54) · Commits · 戴 / test

Following we will begin to add memcg dirty page accounting around __set_page_dirty_{buffers,nobuffers} in vfs layer, so we'd better use vfs interface to avoid exporting those details to filesystems. Since vfs set_page_dirty() should be called under page lock, here we don't need elaborate codes to handle racy anymore, and two WARN_ON() are added to detect such exceptions. Thanks very much for Sage and Yan Zheng's coaching! I tested it in a two server's ceph environment that one is client and the other is mds/osd/mon, and run the following fsx test from xfstests: ./fsx 1MB -N 50000 -p 10000 -l 1048576 ./fsx 10MB -N 50000 -p 10000 -l 10485760 ./fsx 100MB -N 50000 -p 10000 -l 104857600 The fsx does lots of mmap-read/mmap-write/truncate operations and the tests completed successfully without triggering any of WARN_ON. Signed-off-by:

Sha Zhengju <handai.szj@taobao.com> Reviewed-by:

Sage Weil <sage@inktank.com>

fs/ceph/addr.c

+14 −29

Original line number	Diff line number	Diff line
		@@ -70,15 +70,16 @@ static int ceph_set_page_dirty(struct page *page)
		struct address_space *mapping = page->mapping;
		struct inode *inode;
		struct ceph_inode_info *ci;
		int undo = 0;
		struct ceph_snap_context *snapc;
		int ret;

		if (unlikely(!mapping))
		return !TestSetPageDirty(page);

		if (TestSetPageDirty(page)) {
		if (PageDirty(page)) {
		dout("%p set_page_dirty %p idx %lu -- already dirty\n",
		mapping->host, page, page->index);
		BUG_ON(!PagePrivate(page));
		return 0;
		}

		@@ -107,35 +108,19 @@ static int ceph_set_page_dirty(struct page *page)
		snapc, snapc->seq, snapc->num_snaps);
		spin_unlock(&ci->i_ceph_lock);

		/* now adjust page */
		spin_lock_irq(&mapping->tree_lock);
		if (page->mapping) { /* Race with truncate? */
		WARN_ON_ONCE(!PageUptodate(page));
		account_page_dirtied(page, page->mapping);
		radix_tree_tag_set(&mapping->page_tree,
		page_index(page), PAGECACHE_TAG_DIRTY);

		/*
		* Reference snap context in page->private. Also set
		* PagePrivate so that we get invalidatepage callback.
		*/
		BUG_ON(PagePrivate(page));
		page->private = (unsigned long)snapc;
		SetPagePrivate(page);
		} else {
		dout("ANON set_page_dirty %p (raced truncate?)\n", page);
		undo = 1;
		}

		spin_unlock_irq(&mapping->tree_lock);
		ret = __set_page_dirty_nobuffers(page);
		WARN_ON(!PageLocked(page));
		WARN_ON(!page->mapping);

		if (undo)
		/* whoops, we failed to dirty the page */
		ceph_put_wrbuffer_cap_refs(ci, 1, snapc);

		__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);

		BUG_ON(!PageDirty(page));
		return 1;
		return ret;
		}

		/*

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