ThrottleController.cpp revision 9d8d728596234e1e49cb1f8267b190bcc2d4b685 
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
21#include <sys/socket.h>
22#include <sys/stat.h>
23#include <sys/types.h>
24#include <sys/wait.h>
25
26#include <linux/netlink.h>
27#include <linux/rtnetlink.h>
28#include <linux/pkt_sched.h>
29
30#define LOG_TAG "ThrottleController"
31#include <cutils/log.h>
32
33
34#include "ThrottleController.h"
35
36static char TC_PATH[] = "/system/bin/tc";
37
38extern "C" int logwrap(int argc, const char **argv, int background);
39extern "C" int ifc_init(void);
40extern "C" int ifc_up(const char *name);
41extern "C" int ifc_down(const char *name);
42
43int ThrottleController::runTcCmd(const char *cmd) {
44    char buffer[255];
45
46    strncpy(buffer, cmd, sizeof(buffer)-1);
47
48    const char *args[32];
49    char *next = buffer;
50    char *tmp;
51
52    args[0] = TC_PATH;
53    int i = 1;
54
55    while ((tmp = strsep(&next, " "))) {
56        args[i++] = tmp;
57        if (i == 32) {
58            LOGE("tc argument overflow");
59            errno = E2BIG;
60            return -1;
61        }
62    }
63    args[i] = NULL;
64
65    return logwrap(i, args, 0);
66}
67
68int ThrottleController::setInterfaceThrottle(const char *iface, int rxKbps, int txKbps) {
69    char cmd[512];
70    char ifn[65];
71    int rc;
72
73    memset(ifn, 0, sizeof(ifn));
74    strncpy(ifn, iface, sizeof(ifn)-1);
75
76    if (txKbps == -1) {
77        reset(ifn);
78        return 0;
79    }
80
81    /*
82     *
83     * Target interface configuration
84     *
85     */
86
87    /*
88     * Add root qdisc for the interface
89     */
90    sprintf(cmd, "qdisc add dev %s root handle 1: htb default 1 r2q 1000", ifn);
91    if (runTcCmd(cmd)) {
92        LOGE("Failed to add root qdisc (%s)", strerror(errno));
93        goto fail;
94    }
95
96    /*
97     * Add our egress throttling class
98     */
99    sprintf(cmd, "class add dev %s parent 1: classid 1:1 htb rate %dkbit", ifn, txKbps);
100    if (runTcCmd(cmd)) {
101        LOGE("Failed to add egress throttling class (%s)", strerror(errno));
102        goto fail;
103    }
104
105    /*
106     * Bring up the IFD device
107     */
108    ifc_init();
109    if (ifc_up("ifb0")) {
110        LOGE("Failed to up ifb0 (%s)", strerror(errno));
111        goto fail;
112    }
113
114    /*
115     * Add root qdisc for IFD
116     */
117    sprintf(cmd, "qdisc add dev ifb0 root handle 1: htb default 1 r2q 1000");
118    if (runTcCmd(cmd)) {
119        LOGE("Failed to add root ifb qdisc (%s)", strerror(errno));
120        goto fail;
121    }
122
123    /*
124     * Add our ingress throttling class
125     */
126    sprintf(cmd, "class add dev ifb0 parent 1: classid 1:1 htb rate %dkbit", rxKbps);
127    if (runTcCmd(cmd)) {
128        LOGE("Failed to add ingress throttling class (%s)", strerror(errno));
129        goto fail;
130    }
131
132    /*
133     * Add ingress qdisc for pkt redirection
134     */
135    sprintf(cmd, "qdisc add dev %s ingress", ifn);
136    if (runTcCmd(cmd)) {
137        LOGE("Failed to add ingress qdisc (%s)", strerror(errno));
138        goto fail;
139    }
140
141    /*
142     * Add filter to link <ifn> -> ifb0
143     */
144    sprintf(cmd, "filter add dev %s parent ffff: protocol ip prio 10 u32 match "
145            "u32 0 0 flowid 1:1 action mirred egress redirect dev ifb0", ifn);
146    if (runTcCmd(cmd)) {
147        LOGE("Failed to add ifb filter (%s)", strerror(errno));
148        goto fail;
149    }
150
151    return 0;
152fail:
153    reset(ifn);
154    return -1;
155}
156
157void ThrottleController::reset(const char *iface) {
158    char cmd[128];
159
160    sprintf(cmd, "qdisc del dev %s root", iface);
161    runTcCmd(cmd);
162    sprintf(cmd, "qdisc del dev %s ingress", iface);
163    runTcCmd(cmd);
164
165    runTcCmd("qdisc del dev ifb0 root");
166}
167
168int ThrottleController::getInterfaceRxThrottle(const char *iface, int *rx) {
169    *rx = 0;
170    return 0;
171}
172
173int ThrottleController::getInterfaceTxThrottle(const char *iface, int *tx) {
174    *tx = 0;
175    return 0;
176}
177