ThrottleController.cpp revision 5ea0c05a1e7d8e664b808aa1bb1efd08fdb2fb13 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdlib.h>
18#include <errno.h>
19#include <fcntl.h>
20#include <string.h>
21
22#include <sys/socket.h>
23#include <sys/stat.h>
24#include <sys/types.h>
25#include <sys/wait.h>
26
27#include <linux/netlink.h>
28#include <linux/rtnetlink.h>
29#include <linux/pkt_sched.h>
30
31#define LOG_TAG "ThrottleController"
32#include <cutils/log.h>
33
34
35#include "ThrottleController.h"
36
37static char TC_PATH[] = "/system/bin/tc";
38
39extern "C" int system_nosh(const char *command);
40extern "C" int ifc_init(void);
41extern "C" int ifc_up(const char *name);
42extern "C" int ifc_down(const char *name);
43
44int ThrottleController::runTcCmd(const char *cmd) {
45    char *buffer;
46    size_t len = strnlen(cmd, 255);
47    int res;
48
49    if (len == 255) {
50        ALOGE("tc command too long");
51        errno = E2BIG;
52        return -1;
53    }
54
55    asprintf(&buffer, "%s %s", TC_PATH, cmd);
56    res = system_nosh(buffer);
57    free(buffer);
58    return res;
59}
60
61int ThrottleController::setInterfaceThrottle(const char *iface, int rxKbps, int txKbps) {
62    char cmd[512];
63    char ifn[65];
64    int rc;
65
66    memset(ifn, 0, sizeof(ifn));
67    strncpy(ifn, iface, sizeof(ifn)-1);
68
69    if (txKbps == -1) {
70        reset(ifn);
71        return 0;
72    }
73
74    /*
75     *
76     * Target interface configuration
77     *
78     */
79
80    /*
81     * Add root qdisc for the interface
82     */
83    sprintf(cmd, "qdisc add dev %s root handle 1: htb default 1 r2q 1000", ifn);
84    if (runTcCmd(cmd)) {
85        ALOGE("Failed to add root qdisc (%s)", strerror(errno));
86        goto fail;
87    }
88
89    /*
90     * Add our egress throttling class
91     */
92    sprintf(cmd, "class add dev %s parent 1: classid 1:1 htb rate %dkbit", ifn, txKbps);
93    if (runTcCmd(cmd)) {
94        ALOGE("Failed to add egress throttling class (%s)", strerror(errno));
95        goto fail;
96    }
97
98    /*
99     * Bring up the IFD device
100     */
101    ifc_init();
102    if (ifc_up("ifb0")) {
103        ALOGE("Failed to up ifb0 (%s)", strerror(errno));
104        goto fail;
105    }
106
107    /*
108     * Add root qdisc for IFD
109     */
110    sprintf(cmd, "qdisc add dev ifb0 root handle 1: htb default 1 r2q 1000");
111    if (runTcCmd(cmd)) {
112        ALOGE("Failed to add root ifb qdisc (%s)", strerror(errno));
113        goto fail;
114    }
115
116    /*
117     * Add our ingress throttling class
118     */
119    sprintf(cmd, "class add dev ifb0 parent 1: classid 1:1 htb rate %dkbit", rxKbps);
120    if (runTcCmd(cmd)) {
121        ALOGE("Failed to add ingress throttling class (%s)", strerror(errno));
122        goto fail;
123    }
124
125    /*
126     * Add ingress qdisc for pkt redirection
127     */
128    sprintf(cmd, "qdisc add dev %s ingress", ifn);
129    if (runTcCmd(cmd)) {
130        ALOGE("Failed to add ingress qdisc (%s)", strerror(errno));
131        goto fail;
132    }
133
134    /*
135     * Add filter to link <ifn> -> ifb0
136     */
137    sprintf(cmd, "filter add dev %s parent ffff: protocol ip prio 10 u32 match "
138            "u32 0 0 flowid 1:1 action mirred egress redirect dev ifb0", ifn);
139    if (runTcCmd(cmd)) {
140        ALOGE("Failed to add ifb filter (%s)", strerror(errno));
141        goto fail;
142    }
143
144    return 0;
145fail:
146    reset(ifn);
147    return -1;
148}
149
150void ThrottleController::reset(const char *iface) {
151    char cmd[128];
152
153    sprintf(cmd, "qdisc del dev %s root", iface);
154    runTcCmd(cmd);
155    sprintf(cmd, "qdisc del dev %s ingress", iface);
156    runTcCmd(cmd);
157
158    runTcCmd("qdisc del dev ifb0 root");
159}
160
161int ThrottleController::getInterfaceRxThrottle(const char *iface, int *rx) {
162    *rx = 0;
163    return 0;
164}
165
166int ThrottleController::getInterfaceTxThrottle(const char *iface, int *tx) {
167    *tx = 0;
168    return 0;
169}
170