InnoDB may still hang when temporarily running out of buffer pool

diff --git a/storage/innobase/buf/buf0lru.cc b/storage/innobase/buf/buf0lru.cc

index 5ecaa513f41..fa833d96476 100644

--- a/storage/innobase/buf/buf0lru.cc

+++ b/storage/innobase/buf/buf0lru.cc

@@ -449,24 +449,18 @@ buf_block_t *buf_LRU_get_free_block(bool have_mutex)

 			goto got_block;

 		}

 		const bool wake = buf_pool.need_LRU_eviction();

-		mysql_mutex_unlock(&buf_pool.mutex);

 		mysql_mutex_lock(&buf_pool.flush_list_mutex);

-		const auto n_flush = buf_pool.n_flush();

 		if (wake && !buf_pool.page_cleaner_active()) {

 			buf_pool.page_cleaner_wakeup(true);

 		}

 		mysql_mutex_unlock(&buf_pool.flush_list_mutex);

-		mysql_mutex_lock(&buf_pool.mutex);

-		if (!n_flush) {

-			goto not_found;

-		}

-		if (!buf_pool.try_LRU_scan) {

+		if (wake) {

 			my_cond_wait(&buf_pool.done_free,

 				     &buf_pool.mutex.m_mutex);

 		}

 	}

-not_found:

+	IF_DBUG(not_found:,);

 	if (n_iterations > 1) {

 		MONITOR_INC( MONITOR_LRU_GET_FREE_WAITS );

 	}