tree:   https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git netfs-folio-regions
head:   215a4ee495a95cc73256ed76f91cb78bcabd6b8e
commit: f3e6e00066254822783e68e4c3bf9f8904f6ab6a [16/28] netfs: Send write request to multiple destinations
config: arc-randconfig-r043-20210818 (attached as .config)
compiler: arceb-elf-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?id=f3e6e00066254822783e68e4c3bf9f8904f6ab6a
        git remote add dhowells-fs https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
        git fetch --no-tags dhowells-fs netfs-folio-regions
        git checkout f3e6e00066254822783e68e4c3bf9f8904f6ab6a
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=arc 

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

All errors (new ones prefixed by >>):

   fs/netfs/objects.c: In function 'netfs_alloc_write_request':
>> fs/netfs/objects.c:125:24: error: implicit declaration of function 'netfs_is_cache_enabled' [-Werror=implicit-function-declaration]
     125 |         if (!is_dio && netfs_is_cache_enabled(ctx)) {
         |                        ^~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/netfs_is_cache_enabled +125 fs/netfs/objects.c

   114	
   115	struct netfs_write_request *netfs_alloc_write_request(struct address_space *mapping,
   116							      bool is_dio)
   117	{
   118		static atomic_t debug_ids;
   119		struct inode *inode = mapping->host;
   120		struct netfs_i_context *ctx = netfs_i_context(inode);
   121		struct netfs_write_request *wreq;
   122		unsigned int n_streams = ctx->n_wstreams, i;
   123		bool cached = false;
   124	
 > 125		if (!is_dio && netfs_is_cache_enabled(ctx)) {
   126			n_streams++;
   127			cached = true;
   128		}
   129	
   130		wreq = kzalloc(struct_size(wreq, streams, n_streams), GFP_KERNEL);
   131		if (wreq) {
   132			wreq->mapping	= mapping;
   133			wreq->inode	= inode;
   134			wreq->netfs_ops	= ctx->ops;
   135			wreq->max_streams = n_streams;
   136			wreq->debug_id	= atomic_inc_return(&debug_ids);
   137			if (cached)
   138				__set_bit(NETFS_WREQ_WRITE_TO_CACHE, &wreq->flags);
   139			xa_init(&wreq->buffer);
   140			INIT_WORK(&wreq->work, netfs_writeback_worker);
   141			for (i = 0; i < n_streams; i++)
   142				INIT_LIST_HEAD(&wreq->streams[i].subrequests);
   143			refcount_set(&wreq->usage, 1);
   144			atomic_set(&wreq->outstanding, 1);
   145			ctx->ops->init_wreq(wreq);
   146			netfs_stat(&netfs_n_wh_wreq);
   147			trace_netfs_ref_wreq(wreq->debug_id, 1, netfs_wreq_trace_new);
   148		}
   149	
   150		return wreq;
   151	}
   152	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org