On Wed, 2009-09-23 at 18:44 +0800, hongpo gao wrote: > > hello, > > I have a question about idmap. Should I send the mail to > linux-nfs@xxxxxxxxxxxxxxx? The linux-nfs mailing list is preferred over nfsv4@xxxxxxxxxxxxx, if that's what you mean. > The question is as follows: > > In Linux Kernel fs/nfs/idmap.c, > The process will call rpc_queue_upcall in the nfs_idmap_id function, > then it will wait on the waitqueue util the userspace write msg into > the idmap rpc_pipe. > > In userspace idmapd.c file, > the nfscb will read the rpc_pipe by aiomicio(read, ...), write the > rpc_pipe by atomicio(write,...) in the end. > my question is : if the rpc.idmapd deamon is killed in the duration > time that between atomicio(read,.. ) and atomic(write,...), will the > kernel thread will always sleep on the wait_queue? That is to say, > will the rpc_queue_upcall be never return ? No. The kernel tracks whether or not a daemon is listening on the other end of the rpc_pipe, and will therefore return an error should the above scenario happen. Cheers Trond -- 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
