diff --git a/include/linux/sched.h b/include/linux/sched.h index d7d07aa0facf..9c25c8e67030 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -841,6 +841,10 @@ struct task_struct { /* Stalled due to lack of memory */ unsigned in_memstall:1; #endif +#ifdef CONFIG_PAGE_OWNER + /* Used by page_owner=on to detect recursion in page tracking. */ + unsigned in_page_owner:1; +#endif unsigned long atomic_flags; /* Flags requiring atomic access. */ diff --git a/mm/page_owner.c b/mm/page_owner.c index 5c941ca9861d..9661d5320a07 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -98,42 +98,30 @@ static inline struct page_owner *get_page_owner(struct page_ext *page_ext) return (void *)page_ext + page_owner_ops.offset; } -static inline bool check_recursive_alloc(unsigned long *entries, - unsigned int nr_entries, - unsigned long ip) -{ - unsigned int i; - - for (i = 0; i < nr_entries; i++) { - if (entries[i] == ip) - return true; - } - return false; -} - static noinline depot_stack_handle_t save_stack(gfp_t flags) { unsigned long entries[PAGE_OWNER_STACK_DEPTH]; depot_stack_handle_t handle; unsigned int nr_entries; - nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 2); - /* - * We need to check recursion here because our request to - * stackdepot could trigger memory allocation to save new - * entry. New memory allocation would reach here and call - * stack_depot_save_entries() again if we don't catch it. There is - * still not enough memory in stackdepot so it would try to - * allocate memory again and loop forever. + * Avoid recursion. + * + * Sometimes page metadata allocation tracking requires more + * memory to be allocated: + * - when new stack trace is saved to stack depot + * - when backtrace itself is calculated (ia64) */ - if (check_recursive_alloc(entries, nr_entries, _RET_IP_)) + if (current->in_page_owner) return dummy_handle; + current->in_page_owner = 1; + nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 2); handle = stack_depot_save(entries, nr_entries, flags); if (!handle) handle = failure_handle; + current->in_page_owner = 0; return handle; }