net/sunrpc/backchannel_rqst.c:249:2-31: opportunity for str_true_false(list_empty ( & xprt -> bc_pa_list ))

net/sunrpc/backchannel_rqst.c:249:2-31: opportunity for str_true_false(list_empty ( & xprt -> bc_pa_list ))

[kernel test robot]

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-kernel@vger.kernel.org
TO: Anna Schumaker <anna.schumaker@oracle.com>

Hi Anna,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   72d3fcf802c45d00b300f25b848a93c3a2bd7c7e
commit: 7537db24806fdc3d3ec4fef53babdc22c9219e75 NFS: Merge CONFIG_NFS_V4_1 with CONFIG_NFS_V4
date:   8 months ago
:::::: branch date: 15 hours ago
:::::: commit date: 8 months ago
config: i386-randconfig-2101-20260928 (https://download.01.org/0day-ci/archive/20260928/202609281359.Rw9Guzpb-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Fixes: 7537db24806f ("NFS: Merge CONFIG_NFS_V4_1 with CONFIG_NFS_V4")
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Julia Lawall <julia.lawall@inria.fr>
| Closes: https://lore.kernel.org/r/202609281359.Rw9Guzpb-lkp@intel.com/

cocci warnings: (new ones prefixed by >>)
>> net/sunrpc/backchannel_rqst.c:249:2-31: opportunity for str_true_false(list_empty ( & xprt -> bc_pa_list ))

vim +249 net/sunrpc/backchannel_rqst.c

42e5c3e2725ba0 Chuck Lever           2015-10-24  224  
42e5c3e2725ba0 Chuck Lever           2015-10-24  225  void xprt_destroy_bc(struct rpc_xprt *xprt, unsigned int max_reqs)
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  226  {
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  227  	struct rpc_rqst *req = NULL, *tmp = NULL;
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  228  
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  229  	dprintk("RPC:        destroy backchannel transport\n");
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  230  
c4ded8d9771c8e Weston Andros Adamson 2012-10-23  231  	if (max_reqs == 0)
c4ded8d9771c8e Weston Andros Adamson 2012-10-23  232  		goto out;
c4ded8d9771c8e Weston Andros Adamson 2012-10-23  233  
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  234  	spin_lock_bh(&xprt->bc_pa_lock);
669996add4c924 Trond Myklebust       2019-10-17  235  	xprt->bc_alloc_max -= min(max_reqs, xprt->bc_alloc_max);
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  236  	list_for_each_entry_safe(req, tmp, &xprt->bc_pa_list, rq_bc_pa_list) {
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  237  		dprintk("RPC:        req=%p\n", req);
628356791b04ea Trond Myklebust       2014-02-11  238  		list_del(&req->rq_bc_pa_list);
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  239  		xprt_free_allocation(req);
7402a4fedc2bc4 Trond Myklebust       2019-07-16  240  		xprt->bc_alloc_count--;
7402a4fedc2bc4 Trond Myklebust       2019-07-16  241  		atomic_dec(&xprt->bc_slot_count);
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  242  		if (--max_reqs == 0)
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  243  			break;
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  244  	}
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  245  	spin_unlock_bh(&xprt->bc_pa_lock);
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  246  
c4ded8d9771c8e Weston Andros Adamson 2012-10-23  247  out:
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  248  	dprintk("RPC:        backchannel list empty= %s\n",
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01 @249  		list_empty(&xprt->bc_pa_list) ? "true" : "false");
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  250  }
fb7a0b9addbdbb Ricardo Labiaga       2009-04-01  251  

:::::: The code at line 249 was first introduced by commit
:::::: fb7a0b9addbdbbb13b7bc02abf55ee524ea19ce1 nfs41: New backchannel helper routines

:::::: TO: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
:::::: CC: Benny Halevy <bhalevy@panasas.com>

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki