Re: confusing fscache path

[David Howells <dhowells@redhat.com>]

Steve French <smfrench@gmail.com> wrote:

> The path from fscache_uncache_all_inode_pages is:
>    fscache_uncache_all_inode_pages-->__fscache_uncache_all_inode_pages
> (line 132 of fs/fscache/page.c) -->__fscache_uncache_page (locks on
> line 1120 and then on line 1141 "goto done" without unlocking it)

This bit, you mean?

	if (TestClearPageFsCache(page) &&
	    object->cache->ops->uncache_page) {
		/* the cache backend releases the cookie lock */
		fscache_stat(&fscache_n_cop_uncache_page);
		object->cache->ops->uncache_page(object, page);
		fscache_stat_d(&fscache_n_cop_uncache_page);
		goto done;
	}

Note the comment.

Here's the unlock:

	void cachefiles_uncache_page(struct fscache_object *_object, struct page *page)
		__releases(&object->fscache.cookie->lock)
	{
		struct cachefiles_object *object;

		object = container_of(_object, struct cachefiles_object, fscache);

		_enter("%p,{%lu}", object, page->index);

		spin_unlock(&object->fscache.cookie->lock);
	}

David