Commit 5c4d2639 authored Aug 04, 2009 by NeilBrown Committed by J. Bruce Fields Aug 04, 2009

sunrpc/cache: make sure deferred requests eventually get revisited.



While deferred requests normally get revisited quite quickly,
it is possible for a request to remain in the deferral queue
when the cache item is discarded.  We can easily make sure that
doesn't happen by calling cache_revisit_request just before
the final 'put'.

Also there is a small chance that a race would cause one thread to
defer a request against a cache item while another thread is failing
to queue an upcall for that item.  So when the upcall fails, make
sure to revisit all deferred requests.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

parent f866a819

net/sunrpc/cache.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -221,6 +221,7 @@ int cache_check(struct cache_detail *detail,
		switch (cache_make_upcall(detail, h)) {
		case -EINVAL:
		clear_bit(CACHE_PENDING, &h->flags);
		cache_revisit_request(h);
		if (rv == -EAGAIN) {
		set_bit(CACHE_NEGATIVE, &h->flags);
		cache_fresh_unlocked(h, detail,
		@@ -473,8 +474,10 @@ static int cache_clean(void)
		if (!ch)
		current_index ++;
		spin_unlock(&cache_list_lock);
		if (ch)
		if (ch) {
		cache_revisit_request(ch);
		cache_put(ch, d);
		}
		} else
		spin_unlock(&cache_list_lock);