From: Bodo Stroesser <bstroesser@xxxxxxxxxxxxxx>
Date: Thu, 09 Oct 2014 13:06:19 +0200
Subject: [nfs-utils] [PATCH 1/3] rpc.mountd: set nonblocking mode if no libtirpc
If mountd is built without libtirpc and it is started using "-p XXX" option,
the tcp listeners and the sockets waiting for UDP messages are not in
non-blocking mode. Thus if running with multiple threads (-t XX),
all threads will wake up from select on a connection request or a UDP message,
but only one thread will succeed. All others will wait on accept() or read()
for the next event.
Signed-off-by: Bodo Stroesser <bstroesser@xxxxxxxxxxxxxx>
---
--- nfs-utils-1.3.1/support/include/nfslib.h 2014-10-09 12:52:30.000000000 +0200
+++ nfs-utils-1.3.1/support/include/nfslib.h 2014-10-09 12:53:37.000000000 +0200
@@ -174,6 +174,7 @@ void closeall(int min);
int svctcp_socket (u_long __number, int __reuse);
int svcudp_socket (u_long __number);
+int svcsock_nonblock (int __sock);
/* Misc shared code prototypes */
size_t strlcat(char *, const char *, size_t);
--- nfs-utils-1.3.1/support/nfs/svc_socket.c 2014-10-09 12:56:14.000000000 +0200
+++ nfs-utils-1.3.1/support/nfs/svc_socket.c 2014-10-09 13:10:44.000000000 +0200
@@ -76,6 +76,39 @@ int getservport(u_long number, const cha
return 0;
}
+int
+svcsock_nonblock(int sock)
+{
+ int flags;
+
+ if (sock < 0)
+ return sock;
+
+ /* This socket might be shared among multiple processes
+ * if mountd is run multi-threaded. So it is safest to
+ * make it non-blocking, else all threads might wake
+ * one will get the data, and the others will block
+ * indefinitely.
+ * In all cases, transaction on this socket are atomic
+ * (accept for TCP, packet-read and packet-write for UDP)
+ * so O_NONBLOCK will not confuse unprepared code causing
+ * it to corrupt messages.
+ * It generally safest to have O_NONBLOCK when doing an accept
+ * as if we get a RST after the SYN and before accept runs,
+ * we can block despite being told there was an acceptable
+ * connection.
+ */
+ if ((flags = fcntl(sock, F_GETFL)) < 0)
+ perror(_("svc_socket: can't get socket flags"));
+ else if (fcntl(sock, F_SETFL, flags|O_NONBLOCK) < 0)
+ perror(_("svc_socket: can't set socket flags"));
+ else
+ return sock;
+
+ (void) __close(sock);
+ return -1;
+}
+
static int
svc_socket (u_long number, int type, int protocol, int reuse)
{
@@ -113,38 +146,7 @@ svc_socket (u_long number, int type, int
sock = -1;
}
- if (sock >= 0)
- {
- /* This socket might be shared among multiple processes
- * if mountd is run multi-threaded. So it is safest to
- * make it non-blocking, else all threads might wake
- * one will get the data, and the others will block
- * indefinitely.
- * In all cases, transaction on this socket are atomic
- * (accept for TCP, packet-read and packet-write for UDP)
- * so O_NONBLOCK will not confuse unprepared code causing
- * it to corrupt messages.
- * It generally safest to have O_NONBLOCK when doing an accept
- * as if we get a RST after the SYN and before accept runs,
- * we can block despite being told there was an acceptable
- * connection.
- */
- int flags;
- if ((flags = fcntl(sock, F_GETFL)) < 0)
- {
- perror (_("svc_socket: can't get socket flags"));
- (void) __close (sock);
- sock = -1;
- }
- else if (fcntl(sock, F_SETFL, flags|O_NONBLOCK) < 0)
- {
- perror (_("svc_socket: can't set socket flags"));
- (void) __close (sock);
- sock = -1;
- }
- }
-
- return sock;
+ return svcsock_nonblock(sock);
}
/*
--- nfs-utils-1.3.1/support/nfs/rpcmisc.c 2014-10-08 21:22:04.000000000 +0200
+++ nfs-utils-1.3.1/support/nfs/rpcmisc.c 2014-10-08 21:22:36.000000000 +0200
@@ -104,7 +104,7 @@ makesock(int port, int proto)
return -1;
}
- return sock;
+ return svcsock_nonblock(sock);
}
void
ÿôèº{.nÇ+?·?®??+%?Ëÿ±éݶ¥?wÿº{.nÇ+?·¥?{±þwìþ)í?æèw* jg¬±¨ ¶????Ý¢jÿ¾«þG«?éÿ¢¸ ¢·¦j:+v?¨?wèjØm¶?ÿþø ¯ù ®w¥þ?àþf£¢·h??â?úÿ?Ù¥
