On Tue, 11 Oct 2011 05:52:57 -0700 "Myklebust, Trond" <Trond.Myklebust@xxxxxxxxxx> wrote: > > -----Original Message----- > > From: Jeff Layton [mailto:jlayton@xxxxxxxxxx] > > Sent: Tuesday, October 11, 2011 6:12 AM > > To: Pavel Machek > > Cc: Myklebust, Trond; smfrench@xxxxxxxxx; rjw@xxxxxxx; linux- > > pm@xxxxxxxxxxxxxxxxxxxxxxxxxx; linux-cifs@xxxxxxxxxxxxxxx; linux- > > nfs@xxxxxxxxxxxxxxx; john@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH 3/4] sunrpc: make rpc_wait_bit_killable handle > freeze > > events > > > > On Tue, 11 Oct 2011 08:19:23 +0200 > > Pavel Machek <pavel@xxxxxx> wrote: > > > > > On Wed 2011-09-28 07:52:40, Jeff Layton wrote: > > > > Allow the wait_on_bit_killable sleeps in SUNRPC layer to respect > the > > > > freezer. This should allow suspend and hibernate events to occur, > > > > even when there are RPC's pending on the wire. > > > > > > Will the RPC protocols used handle that correctly? What will happen > > > during resume? > > > > > > > That depends on the state of the socket during resume. If the > > suspend/resume is quick enough, then the socket may still be > connected, or > > if we're using UDP then we might just get the reply and carry on > successfully. > > Otherwise, the call will eventually time out, or will be cancelled > when the > > kernel finds that the socket has been closed. > > > > Either way, this should do the right thing. > > Well... The problem when this sort of thing happens is with the replay > cache. If the RPC in question was a mkdir, for instance, then replaying > the RPC call when you wake up can be problematic because chances are > that the server will have forgotten who created the directory, and so > will reply with EEXIST instead of OK. > However this is a generic problem when the client is unable to talk to > the server for a while, and is not particular to suspend. > Yeah, that's always a problem. You can hit the same thing if you just unplug the cable from the network interface at an inopportune time. I think this patch is really the best we can do under those circumstances. Eventually we'll all be on 4.1 with sessions and this problem will go away, right? ;) -- Jeff Layton <jlayton@xxxxxxxxxx> -- 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
