1 files changed, 102 insertions, 36 deletions

diff --git a/sys/net/netisr.h b/sys/net/netisr.h
index 79293027e544..f299b2e84a5c 100644
--- a/sys/net/netisr.h
+++ b/sys/net/netisr.h
@@ -1,6 +1,6 @@
 /*-
- * Copyright (c) 1980, 1986, 1989, 1993
- *	The Regents of the University of California.  All rights reserved.
+ * Copyright (c) 2007-2009 Robert N. M. Watson
+ * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -10,14 +10,11 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 4. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
@@ -26,20 +23,18 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	@(#)netisr.h	8.1 (Berkeley) 6/10/93
  * $FreeBSD$
  */
 
 #ifndef _NET_NETISR_H_
 #define _NET_NETISR_H_
+#ifdef _KERNEL
 
 /*
  * The netisr (network interrupt service routine) provides a deferred
  * execution evironment in which (generally inbound) network processing can
- * take place.  Protocols register handlers and, optionally, packet queues;
- * when packets are delivered to the queue, the protocol handler will be
- * executed directly, or via deferred dispatch depending on the
- * circumstances.
+ * take place.  Protocols register handlers which will be executed directly,
+ * or via deferred dispatch, depending on the circumstances.
  *
  * Historically, this was implemented by the BSD software ISR facility; it is
  * now implemented via a software ithread (SWI).
@@ -53,37 +48,108 @@
 #define	NETISR_ATALK1	17		/* Appletalk phase 1 */
 #define	NETISR_ARP	18		/* same as AF_LINK */
 #define	NETISR_IPX	23		/* same as AF_IPX */
+#define	NETISR_ETHER	24		/* ethernet input */
 #define	NETISR_IPV6	27
 #define	NETISR_NATM	28
 #define	NETISR_POLLMORE	31		/* polling callback, must be last */
 
-#ifndef LOCORE
-#ifdef _KERNEL
+/*-
+ * Protocols express ordering constraints and affinity preferences by
+ * implementing one or neither of nh_m2flow and nh_m2cpuid, which are used by
+ * netisr to determine which per-CPU workstream to assign mbufs to.
+ *
+ * The following policies may be used by protocols:
+ *
+ * NETISR_POLICY_SOURCE - netisr should maintain source ordering without
+ *                        advice from the protocol.  netisr will ignore any
+ *                        flow IDs present on the mbuf for the purposes of
+ *                        work placement.
+ *
+ * NETISR_POLICY_FLOW - netisr should maintain flow ordering as defined by
+ *                      the mbuf header flow ID field.  If the protocol
+ *                      implements nh_m2flow, then netisr will query the
+ *                      protocol in the event that the mbuf doesn't have a
+ *                      flow ID, falling back on source ordering.
+ *
+ * NETISR_POLICY_CPU - netisr will delegate all work placement decisions to
+ *                     the protocol, querying nh_m2cpuid for each packet.
+ *
+ * Protocols might make decisions about work placement based on an existing
+ * calculated flow ID on the mbuf, such as one provided in hardware, the
+ * receive interface pointed to by the mbuf (if any), the optional source
+ * identifier passed at some dispatch points, or even parse packet headers to
+ * calculate a flow.  Both protocol handlers may return a new mbuf pointer
+ * for the chain, or NULL if the packet proves invalid or m_pullup() fails.
+ *
+ * XXXRW: If we eventually support dynamic reconfiguration, there should be
+ * protocol handlers to notify them of CPU configuration changes so that they
+ * can rebalance work.
+ */
+struct mbuf;
+typedef void		 netisr_handler_t (struct mbuf *m);
+typedef struct mbuf	*netisr_m2cpuid_t(struct mbuf *m, uintptr_t source,
+			 u_int *cpuid);
+typedef	struct mbuf	*netisr_m2flow_t(struct mbuf *m, uintptr_t source);
+
+#define	NETISR_POLICY_SOURCE	1	/* Maintain source ordering. */
+#define	NETISR_POLICY_FLOW	2	/* Maintain flow ordering. */
+#define	NETISR_POLICY_CPU	3	/* Protocol determines CPU placement. */
+
+/*
+ * Data structure describing a protocol handler.
+ */
+struct netisr_handler {
+	const char	*nh_name;	/* Character string protocol name. */
+	netisr_handler_t *nh_handler;	/* Protocol handler. */
+	netisr_m2flow_t	*nh_m2flow;	/* Query flow for untagged packet. */
+	netisr_m2cpuid_t *nh_m2cpuid;	/* Query CPU to process mbuf on. */
+	u_int		 nh_proto;	/* Integer protocol ID. */
+	u_int		 nh_qlimit;	/* Maximum per-CPU queue depth. */
+	u_int		 nh_policy;	/* Work placement policy. */
+	u_int		 nh_ispare[5];	/* For future use. */
+	void		*nh_pspare[4];	/* For future use. */
+};
 
-void legacy_setsoftnet(void);
+/*
+ * Register, unregister, and other netisr handler management functions.
+ */
+void	netisr_clearqdrops(const struct netisr_handler *nhp);
+void	netisr_getqdrops(const struct netisr_handler *nhp,
+	    u_int64_t *qdropsp);
+void	netisr_getqlimit(const struct netisr_handler *nhp, u_int *qlimitp);
+void	netisr_register(const struct netisr_handler *nhp);
+int	netisr_setqlimit(const struct netisr_handler *nhp, u_int qlimit);
+void	netisr_unregister(const struct netisr_handler *nhp);
 
-extern volatile unsigned int	netisr;	/* scheduling bits for network */
-#define	schednetisr(anisr) do {						\
-	atomic_set_rel_int(&netisr, 1 << (anisr));			\
-	legacy_setsoftnet();						\
-} while (0)
-/* used to atomically schedule multiple netisrs */
-#define	schednetisrbits(isrbits) do {					\
-	atomic_set_rel_int(&netisr, isrbits);				\
-	legacy_setsoftnet();						\
-} while (0)
+/*
+ * Process a packet destined for a protocol, and attempt direct dispatch.
+ * Supplemental source ordering information can be passed using the _src
+ * variant.
+ */
+int	netisr_dispatch(u_int proto, struct mbuf *m);
+int	netisr_dispatch_src(u_int proto, uintptr_t source, struct mbuf *m);
+int	netisr_queue(u_int proto, struct mbuf *m);
+int	netisr_queue_src(u_int proto, uintptr_t source, struct mbuf *m);
 
-struct ifqueue;
-struct mbuf;
+/*
+ * Provide a default implementation of "map an ID to a CPU ID".
+ */
+u_int	netisr_default_flow2cpu(u_int flowid);
 
-typedef void netisr_t (struct mbuf *);
-  
-void	netisr_dispatch(int, struct mbuf *);
-int	netisr_queue(int, struct mbuf *);
-void	netisr_register(int, netisr_t *, struct ifqueue *, int);
-void	netisr_unregister(int);
+/*
+ * Utility routines to return the number of CPUs participting in netisr, and
+ * to return a mapping from a number to a CPU ID that can be used with the
+ * scheduler.
+ */
+u_int	netisr_get_cpucount(void);
+u_int	netisr_get_cpuid(u_int cpunumber);
 
-#endif
-#endif
+/*
+ * Interfaces between DEVICE_POLLING and netisr.
+ */
+void	netisr_sched_poll(void);
+void	netisr_poll(void);
+void	netisr_pollmore(void);
 
-#endif
+#endif /* !_KERNEL */
+#endif /* !_NET_NETISR_H_ */