Re: set_page_dirty/page_launder deadlock

[Chris Mason]

On Sunday, January 14, 2001 10:56:10 AM -0800 Linus Torvalds
<[e-mail]> wrote:

>> Marcelo Tosatti writes:
>>  > 
>>  > While taking a look at page_launder()...
>> 
>>  ...
>> 
>>  > set_page_dirty() may lock the pagecache_lock which means potential
>>  > deadlock since we have the pagemap_lru_lock locked.
>> 
> 
> Well, as the new shm code doesn't return 1 any more, the whole locked page
> handling should just be deleted. ramfs always just re-marked the page
> dirty in its own "writepage()" function, so it was only shmfs that ever
> returned this special case, and because of other issues it already got
> excised by Christoph..
> 

Then I'm confused by the code in 2.4.1pre8:

-chris

/*
 * Move the page from the page cache to the swap cache
 */
static int shmem_writepage(struct page * page)
{
	int error;
	struct shmem_inode_info *info;
	swp_entry_t *entry, swap;

	info = &page->mapping->host->u.shmem_i;
	if (info->locked)
		return 1;
	swap = __get_swap_page(2);
	if (!swap.val)
		return 1;