On 12/01/2017 06:02 PM, Kirill Tkhai wrote: > When there are more than 2 users of a page, __tcache_page_tree_delete() > fails to freeze it. We skip it and never try to freeze it again. > > In this case the page remains not invalidated, and tcache_node->nr_pages > never decremented. Later, we catch WARN_ON() reporting about this. > > tcache_shrink_scan() tcache_destroy_pool > tcache_lru_isolate() > tcache_grab_pool() > ... > page_cache_get_speculative() -->cnt == 2 > > ... > tcache_put_pool() --> pool cnt zero > ... > wait_for_completion(&pool->completion); > tcache_reclaim_pages > tcache_invalidate_node_pages() > __tcache_reclaim_page() tcache_lookup() > > page_cache_get_speculative --> cnt == 3 > > __tcache_page_tree_delete > page_ref_freeze(2) -->fail > page_ref_freeze(2) -->fail > > The patch fixes the problem. In case of we failed to invalidate a page, > we remember this, and return to such pages after others are invalidated. > > https://jira.sw.ru/browse/PSBM-78354 > > v2: Also fix tcache_detach_page() > > Signed-off-by: Kirill Tkhai <ktk...@virtuozzo.com> > ---
Acked-by: Andrey Ryabinin <aryabi...@virtuozzo.com> _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
