Merge a change from mysql-5.1-innodb:

------------------------------------------------------------
revno: 3502
revision-id: marko.makela@oracle.com-20100608114055-7b04ytuqz0lde6v1
parent: jimmy.yang@oracle.com-20100603134448-itzduhwgbw0b8nlh
committer: Marko Mäkelä <marko.makela@oracle.com>
branch nick: 5.1-innodb
timestamp: Tue 2010-06-08 14:40:55 +0300
message:
  buf_page_get_gen(): Pass file,line to rw_lock_x_lock().

storage/innobase/buf/buf0buf.c

@@ -2957,7 +2957,7 @@ buf_page_get_gen(
 
 		block->page.buf_fix_count = 1;
 		buf_block_set_io_fix(block, BUF_IO_READ);
-		rw_lock_x_lock(&block->lock);
+		rw_lock_x_lock_func(&block->lock, 0, file, line);
 
 		UNIV_MEM_INVALID(bpage, sizeof *bpage);