1/*
| 1/*-
2 * Copyright (c) 2001,2002,2003 Jonathan Lemon <jlemon@FreeBSD.org>
|
2 * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
| 3 * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
|
9 * notice unmodified, this list of conditions, and the following
10 * disclaimer.
| 10 * notice, this list of conditions and the following disclaimer.
|
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
| 11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
|
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
| 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
|
25 *
| 26 *
|
26 * $FreeBSD: head/sys/net/netisr.c 103781 2002-09-22 05:56:41Z jake $
| 27 * $FreeBSD: head/sys/net/netisr.c 111888 2003-03-04 23:19:55Z jlemon $
|
27 */
28
29#include <sys/param.h>
| 28 */
29
30#include <sys/param.h>
|
30#include <sys/systm.h>
| |
31#include <sys/bus.h>
| 31#include <sys/bus.h>
|
32#include <sys/proc.h>
| 32#include <sys/rtprio.h>
33#include <sys/systm.h>
|
33#include <sys/interrupt.h>
34#include <sys/kernel.h>
| 34#include <sys/interrupt.h>
35#include <sys/kernel.h>
|
| 36#include <sys/kthread.h>
37#include <sys/lock.h>
38#include <sys/malloc.h>
39#include <sys/proc.h>
40#include <sys/random.h>
41#include <sys/resourcevar.h>
42#include <sys/sysctl.h>
43#include <sys/unistd.h>
44#include <machine/atomic.h>
45#include <machine/cpu.h>
46#include <machine/stdarg.h>
|
35
| 47
|
| 48#include <sys/mbuf.h>
49#include <sys/socket.h>
50
51#include <net/if.h>
52#include <net/if_types.h>
53#include <net/if_var.h>
|
36#include <net/netisr.h>
37
| 54#include <net/netisr.h>
55
|
38static void swi_net(void *);
| 56volatile unsigned int netisr; /* scheduling bits for network */
|
39
| 57
|
40void *net_ih;
41volatile unsigned int netisr;
42void (*netisrs[32])(void);
| 58struct netisr {
59 netisr_t *ni_handler;
60 struct ifqueue *ni_queue;
61} netisrs[32];
|
43
| 62
|
| 63static struct mtx netisr_mtx;
64static void *net_ih;
65
|
44void
45legacy_setsoftnet(void)
46{
47 swi_sched(net_ih, 0);
48}
49
| 66void
67legacy_setsoftnet(void)
68{
69 swi_sched(net_ih, 0);
70}
71
|
50int
51register_netisr(int num, netisr_t *handler)
| 72void
73netisr_register(int num, netisr_t *handler, struct ifqueue *inq)
|
52{
53
| 74{
75
|
54 if (num < 0 || num >= (sizeof(netisrs)/sizeof(*netisrs)) ) {
55 printf("register_netisr: bad isr number: %d\n", num);
56 return (EINVAL);
| 76 KASSERT(!(num < 0 || num >= (sizeof(netisrs)/sizeof(*netisrs))),
77 ("bad isr %d", num));
78 netisrs[num].ni_handler = handler;
79 netisrs[num].ni_queue = inq;
80}
81
82void
83netisr_unregister(int num)
84{
85 struct netisr *ni;
86 int s;
87
88 KASSERT(!(num < 0 || num >= (sizeof(netisrs)/sizeof(*netisrs))),
89 ("bad isr %d", num));
90 ni = &netisrs[num];
91 ni->ni_handler = NULL;
92 if (ni->ni_queue != NULL) {
93 s = splimp();
94 IF_DRAIN(ni->ni_queue);
95 splx(s);
|
57 }
| 96 }
|
58 netisrs[num] = handler;
59 return (0);
| |
60}
61
| 97}
98
|
62int
63unregister_netisr(int num)
| 99struct isrstat {
100 int isrs_count; /* dispatch count */
101 int isrs_directed; /* ...successfully dispatched */
102 int isrs_deferred; /* ...queued instead */
103 int isrs_bypassed; /* bypassed queued packets */
104 int isrs_queued; /* intentionally queueued */
105 int isrs_swi_count; /* swi_net handlers called */
106};
107static struct isrstat isrstat;
108
109SYSCTL_NODE(_net, OID_AUTO, isr, CTLFLAG_RW, 0, "netisr counters");
110
111static int netisr_enable = 0;
112SYSCTL_INT(_net_isr, OID_AUTO, enable, CTLFLAG_RW,
113 &netisr_enable, 0, "enable direct dispatch");
114
115SYSCTL_INT(_net_isr, OID_AUTO, count, CTLFLAG_RD,
116 &isrstat.isrs_count, 0, "");
117SYSCTL_INT(_net_isr, OID_AUTO, directed, CTLFLAG_RD,
118 &isrstat.isrs_directed, 0, "");
119SYSCTL_INT(_net_isr, OID_AUTO, deferred, CTLFLAG_RD,
120 &isrstat.isrs_deferred, 0, "");
121SYSCTL_INT(_net_isr, OID_AUTO, bypassed, CTLFLAG_RD,
122 &isrstat.isrs_bypassed, 0, "");
123SYSCTL_INT(_net_isr, OID_AUTO, queued, CTLFLAG_RD,
124 &isrstat.isrs_queued, 0, "");
125SYSCTL_INT(_net_isr, OID_AUTO, swi_count, CTLFLAG_RD,
126 &isrstat.isrs_swi_count, 0, "");
127
128/*
129 * Call the netisr directly instead of queueing the packet, if possible.
130 *
131 * Ideally, the permissibility of calling the routine would be determined
132 * by checking if splnet() was asserted at the time the device interrupt
133 * occurred; if so, this indicates that someone is in the network stack.
134 *
135 * However, bus_setup_intr uses INTR_TYPE_NET, which sets splnet before
136 * calling the interrupt handler, so the previous mask is unavailable.
137 * Approximate this by checking intr_nesting_level instead; if any SWI
138 * handlers are running, the packet is queued instead.
139 */
140void
141netisr_dispatch(int num, struct mbuf *m)
|
64{
| 142{
|
| 143 struct netisr *ni;
|
65
| 144
|
66 if (num < 0 || num >= (sizeof(netisrs)/sizeof(*netisrs)) ) {
67 printf("unregister_netisr: bad isr number: %d\n", num);
68 return (EINVAL);
| 145 isrstat.isrs_count++;
146 KASSERT(!(num < 0 || num >= (sizeof(netisrs)/sizeof(*netisrs))),
147 ("bad isr %d", num));
148 ni = &netisrs[num];
149 KASSERT(ni->ni_queue != NULL, ("no queue for isr %d", num));
150 if (netisr_enable && mtx_trylock(&netisr_mtx)) {
151 isrstat.isrs_directed++;
152 /*
153 * One slight problem here is that packets might bypass
154 * each other in the stack, if an earlier one happened
155 * to get stuck in the queue.
156 *
157 * we can either:
158 * a. drain the queue before handling this packet,
159 * b. fallback to queueing the packet,
160 * c. sweep the issue under the rug and ignore it.
161 *
162 * Currently, we do c), and keep a rough event counter.
163 */
164 if (_IF_QLEN(ni->ni_queue) > 0)
165 isrstat.isrs_bypassed++;
166 ni->ni_handler(m);
167 mtx_unlock(&netisr_mtx);
168 } else {
169 isrstat.isrs_deferred++;
170 if (IF_HANDOFF(ni->ni_queue, m, NULL))
171 schednetisr(num);
|
69 }
| 172 }
|
70 netisrs[num] = NULL;
71 return (0);
| |
72}
73
| 173}
174
|
74#ifdef DEVICE_POLLING
75void netisr_pollmore(void);
76#endif
| 175/*
176 * Same as above, but always queue.
177 * This is either used in places where we are not confident that
178 * direct dispatch is possible, or where queueing is required.
179 */
180int
181netisr_queue(int num, struct mbuf *m)
182{
183 struct netisr *ni;
184
185 KASSERT(!(num < 0 || num >= (sizeof(netisrs)/sizeof(*netisrs))),
186 ("bad isr %d", num));
187 ni = &netisrs[num];
188 KASSERT(ni->ni_queue != NULL, ("no queue for isr %d", num));
189 isrstat.isrs_queued++;
190 if (!IF_HANDOFF(ni->ni_queue, m, NULL))
191 return (0);
192 schednetisr(num);
193 return (1);
194}
|
77
78static void
79swi_net(void *dummy)
80{
| 195
196static void
197swi_net(void *dummy)
198{
|
| 199 struct netisr *ni;
200 struct mbuf *m;
|
81 u_int bits;
82 int i;
| 201 u_int bits;
202 int i;
|
83
| |
84#ifdef DEVICE_POLLING
| 203#ifdef DEVICE_POLLING
|
85 for (;;) {
86 int pollmore;
| 204 const int polling = 1;
205#else
206 const int polling = 0;
|
87#endif
| 207#endif
|
88 bits = atomic_readandclear_int(&netisr);
89#ifdef DEVICE_POLLING
90 if (bits == 0)
91 return;
92 pollmore = bits & (1 << NETISR_POLL);
93#endif
94 while ((i = ffs(bits)) != 0) {
95 i--;
96 if (netisrs[i] != NULL)
97 netisrs[i]();
98 else
99 printf("swi_net: unregistered isr number: %d.\n", i);
100 bits &= ~(1 << i);
101 }
102#ifdef DEVICE_POLLING
103 if (pollmore)
104 netisr_pollmore();
105 }
106#endif
| 208
209 mtx_lock(&netisr_mtx);
210 do {
211 bits = atomic_readandclear_int(&netisr);
212 if (bits == 0)
213 break;
214 while ((i = ffs(bits)) != 0) {
215 isrstat.isrs_swi_count++;
216 i--;
217 bits &= ~(1 << i);
218 ni = &netisrs[i];
219 if (ni->ni_handler == NULL) {
220 printf("swi_net: unregistered isr %d.\n", i);
221 continue;
222 }
223 if (ni->ni_queue == NULL)
224 ni->ni_handler(NULL);
225 else
226 for (;;) {
227 IF_DEQUEUE(ni->ni_queue, m);
228 if (m == NULL)
229 break;
230 ni->ni_handler(m);
231 }
232 }
233 } while (polling);
234 mtx_unlock(&netisr_mtx);
|
107}
108
109static void
110start_netisr(void *dummy)
111{
112
| 235}
236
237static void
238start_netisr(void *dummy)
239{
240
|
| 241 mtx_init(&netisr_mtx, "netisr lock", NULL, MTX_DEF);
|
113 if (swi_add(NULL, "net", swi_net, NULL, SWI_NET, 0, &net_ih))
114 panic("start_netisr");
115}
116SYSINIT(start_netisr, SI_SUB_SOFTINTR, SI_ORDER_FIRST, start_netisr, NULL)
| 242 if (swi_add(NULL, "net", swi_net, NULL, SWI_NET, 0, &net_ih))
243 panic("start_netisr");
244}
245SYSINIT(start_netisr, SI_SUB_SOFTINTR, SI_ORDER_FIRST, start_netisr, NULL)
|