Over NFS, an open() call could result in multiple over-the-wire

GETATTRs being generated - one from lookup()/namei() and the other
from nfs_open() (for cto consistency). This change eliminates the
GETATTR in nfs_open() if an otw GETATTR was done from the namei()
path. Instead of extending the vop interface, we timestamp each attr
load, and use this to detect whether a GETATTR was done from namei()
for this syscall. Introduces a thread-local variable that counts the
syscalls made by the thread and uses <pid, tid, thread syscalls> as
the attrload timestamp. Thanks to jhb@ and peter@ for a discussion on
thread state that could be used as the timestamp with minimal overhead.

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/nfsclient/nfs_socket.c b/sys/nfsclient/nfs_socket.c
index 6036050..a28d837 100644
--- a/sys/nfsclient/nfs_socket.c
+++ b/sys/nfsclient/nfs_socket.c
@@ -1412,7 +1412,7 @@ nfs_timer(void *arg)
 		}
 		if (rep->r_rtt >= 0) {
 			rep->r_rtt++;
-			if (nmp->nm_flag & NFSMNT_DUMBTIMR)
+			if ((nmp->nm_flag & NFSMNT_DUMBTIMR) || (nmp->nm_sotype == SOCK_STREAM))
 				timeo = nmp->nm_timeo;
 			else
 				timeo = nfs_estimate_rto(nmp, rep->r_procnum);