tree:   https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git ftrace/fgraph-multi
head:   978dc256bd4d08df876d58b4fa01ba4cb3926242
commit: be13406cc12900ea57d62a9afcc33c4e11a1993f [34/40] function_graph: Have the instances use their own ftrace_ops for filtering
config: i386-randconfig-r035-20210416 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git/commit/?id=be13406cc12900ea57d62a9afcc33c4e11a1993f
        git remote add trace https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
        git fetch --no-tags trace ftrace/fgraph-multi
        git checkout be13406cc12900ea57d62a9afcc33c4e11a1993f
        # save the attached .config to linux build tree
        make W=1 W=1 ARCH=i386 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   kernel/trace/fgraph.c:481:15: warning: no previous prototype for 'ftrace_return_to_handler' [-Wmissing-prototypes]
     481 | unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
         |               ^~~~~~~~~~~~~~~~~~~~~~~~
   kernel/trace/fgraph.c: In function 'ftrace_return_to_handler':
   kernel/trace/fgraph.c:483:27: warning: variable 'ret_stack' set but not used [-Wunused-but-set-variable]
     483 |  struct ftrace_ret_stack *ret_stack;
         |                           ^~~~~~~~~
   kernel/trace/fgraph.c: At top level:
>> kernel/trace/fgraph.c:613:6: warning: no previous prototype for 'fgraph_init_ops' [-Wmissing-prototypes]
     613 | void fgraph_init_ops(struct ftrace_ops *dst_ops,
         |      ^~~~~~~~~~~~~~~
   kernel/trace/fgraph.c:633:6: warning: no previous prototype for 'ftrace_graph_sleep_time_control' [-Wmissing-prototypes]
     633 | void ftrace_graph_sleep_time_control(bool enable)
         |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   kernel/trace/fgraph.c:645:46: error: initialization of 'trace_func_graph_ret_t' {aka 'void (*)(struct ftrace_graph_ret *, struct fgraph_ops *)'} from incompatible pointer type 'void (*)(struct ftrace_graph_ret *)' [-Werror=incompatible-pointer-types]
     645 | trace_func_graph_ret_t ftrace_graph_return = ftrace_stub_graph;
         |                                              ^~~~~~~~~~~~~~~~~
   kernel/trace/fgraph.c: In function 'unregister_ftrace_graph':
   kernel/trace/fgraph.c:924:23: error: assignment to 'trace_func_graph_ret_t' {aka 'void (*)(struct ftrace_graph_ret *, struct fgraph_ops *)'} from incompatible pointer type 'void (*)(struct ftrace_graph_ret *)' [-Werror=incompatible-pointer-types]
     924 |   ftrace_graph_return = ftrace_stub_graph;
         |                       ^
   cc1: some warnings being treated as errors


vim +/fgraph_init_ops +613 kernel/trace/fgraph.c

   612	
 > 613	void fgraph_init_ops(struct ftrace_ops *dst_ops,
   614			     struct ftrace_ops *src_ops)
   615	{
   616		dst_ops->func = ftrace_stub;
   617		dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_FL_STUB;
   618	

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0-DAY CI Kernel Test Service, Intel Corporation
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