1 files changed, 69 insertions, 0 deletions
diff --git a/pfinet/sched.c b/pfinet/sched.c
new file mode 100644
index 00000000..53f0cb09
--- /dev/null
+++ b/pfinet/sched.c
@@ -0,0 +1,69 @@
+/*
+   Copyright (C) 1995, 1996, 2000 Free Software Foundation, Inc.
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   The GNU Hurd is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */
+
+#include "pfinet.h"
+
+#include <asm/system.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+
+struct mutex global_lock = MUTEX_INITIALIZER;
+struct mutex net_bh_lock = MUTEX_INITIALIZER;
+struct condition net_bh_wakeup = CONDITION_INITIALIZER;
+
+struct task_struct current_contents; /* zeros are right default values */
+
+
+/* Wake up the owner of the SOCK.  If HOW is zero, then just
+   send SIGIO.  If HOW is one, then send SIGIO only if the
+   SO_WAITDATA flag is off.  If HOW is two, then send SIGIO
+   only if the SO_NOSPACE flag is on, and also clear it. */
+int
+sock_wake_async (struct socket *sock, int how)
+{
+  /* For now, do nothing. XXX  */
+  return 0;
+}
+
+
+/* This function is the "net_bh worker thread".
+   The packet receiver thread calls net/core/dev.c::netif_rx with a packet;
+   netif_rx either drops the packet, or enqueues it and wakes us up
+   via mark_bh which is really condition_broadcast on net_bh_wakeup.
+   The packet receiver thread holds net_bh_lock while calling netif_rx.
+   We wake up and take global_lock, which locks out RPC service threads.
+   We then also take net_bh_lock running net_bh.
+   Thus, only this thread running net_bh locks out the packet receiver
+   thread (which takes only net_bh_lock while calling netif_rx), so packets
+   are quickly moved from the Mach port's message queue to the `backlog'
+   queue, or dropped, without synchronizing with RPC service threads.
+   (The RPC service threads lock out the running of net_bh, but not
+   the queuing/dropping of packets in netif_rx.)  */
+any_t
+net_bh_worker (any_t arg)
+{
+  __mutex_lock (&global_lock);
+  while (1)
+    {
+      condition_wait (&net_bh_wakeup, &global_lock);
+      __mutex_lock (&net_bh_lock);
+      net_bh ();
+      __mutex_unlock (&net_bh_lock);
+    }
+}