On Mon, Aug 18, 2014 at 12:18 PM, J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote: > On Mon, Aug 18, 2014 at 12:41:24AM +0800, kbuild test robot wrote: >> tree: git://linux-nfs.org/~bfields/linux.git nfsd-next >> head: da8b8f7602ed3b8105c6247a2844455fec72caaa >> commit: 983c684466e02b21f83c025ea539deee6c0aeac0 [5/23] SUNRPC: get rid of the request wait queue >> config: make ARCH=xtensa allyesconfig >> >> All error/warnings: >> >> net/sunrpc/svc_xprt.c: In function 'svc_recv': >> >> net/sunrpc/svc_xprt.c:794:20: error: 'current_task' undeclared (first use in this function) >> rqstp->rq_task = current_task; >> ^ >> net/sunrpc/svc_xprt.c:794:20: note: each undeclared identifier is reported only once for each function it appears in >> >> vim +/current_task +794 net/sunrpc/svc_xprt.c >> >> 788 printk(KERN_ERR >> 789 "svc_recv: service %p, transport not NULL!\n", >> 790 rqstp); >> 791 >> 792 /* Make sure the task pointer is set! */ >> 793 if (WARN_ON_ONCE(!rqstp->rq_task)) >> > 794 rqstp->rq_task = current_task; > > I appreciate the effort to fail gracefully here, but maybe this would be > a case for simple BUG_ON()? > > I don't think there are normally any important locks held here, and I > can't see any other reason why killing a server thread would bring a box > down. > > And the first developer to forget to set rq_task on a newly created > server will get an immediate bug, so this should be obvious enough. > Unless there's fear of a race between starting the thread and setting > rq_task? > No, there is no fear of a race. I'm fine with removing the above check altogether and just letting code Oops if it turns out that we add new cases that don't set rq_task. Ultimately, though, I think we need a better interface for starting RPC server threads; something that combines svc_prepare_thread() and kthread_run() into a single function call and that can thus set rqstp->rq_task correctly. -- Trond Myklebust Linux NFS client maintainer, PrimaryData trond.myklebust@xxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
