1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
/*
* Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The OpenAirInterface Software Alliance licenses this file to You under
* the OAI Public License, Version 1.1 (the "License"); you may not use this file
* except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.openairinterface.org/?page_id=698
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*-------------------------------------------------------------------------------
* For more information about the OpenAirInterface (OAI) Software Alliance:
* contact@openairinterface.org
*/
/* This module provides a separate process to run system().
* The communication between this process and the main processing
* is done through unix pipes.
*
* Motivation: the UE sets its IP address using system() and
* that disrupts realtime processing in some cases. Having a
* separate process solves this problem.
*/
#define _GNU_SOURCE
#include "system.h"
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>
#include <pthread.h>
#include <string.h>
#include <stdint.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
#include <common/utils/assertions.h>
#include <common/utils/LOG/log.h>
#define MAX_COMMAND 4096
static int command_pipe_read;
static int command_pipe_write;
static int result_pipe_read;
static int result_pipe_write;
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
static int module_initialized = 0;
/********************************************************************/
/* util functions */
/********************************************************************/
static void lock_system(void) {
if (pthread_mutex_lock(&lock) != 0) {
printf("pthread_mutex_lock fails\n");
abort();
}
}
static void unlock_system(void) {
if (pthread_mutex_unlock(&lock) != 0) {
printf("pthread_mutex_unlock fails\n");
abort();
}
}
static void write_pipe(int p, char *b, int size) {
while (size) {
int ret = write(p, b, size);
if (ret <= 0) exit(0);
b += ret;
size -= ret;
}
}
static void read_pipe(int p, char *b, int size) {
while (size) {
int ret = read(p, b, size);
if (ret <= 0) exit(0);
b += ret;
size -= ret;
}
}
/********************************************************************/
/* background process */
/********************************************************************/
/* This function is run by background process. It waits for a command,
* runs it, and reports status back. It exits (in normal situations)
* when the main process exits, because then a "read" on the pipe
* will return 0, in which case "read_pipe" exits.
*/
static void background_system_process(void) {
int len;
int ret;
char command[MAX_COMMAND+1];
while (1) {
read_pipe(command_pipe_read, (char *)&len, sizeof(int));
read_pipe(command_pipe_read, command, len);
ret = system(command);
write_pipe(result_pipe_write, (char *)&ret, sizeof(int));
}
}
/********************************************************************/
/* background_system() */
/* return -1 on error, 0 on success */
/********************************************************************/
int background_system(char *command) {
int res;
int len;
if (module_initialized == 0) {
printf("FATAL: calling 'background_system' but 'start_background_system' was not called\n");
abort();
}
len = strlen(command)+1;
if (len > MAX_COMMAND) {
printf("FATAL: command too long. Increase MAX_COMMAND (%d).\n", MAX_COMMAND);
printf("command was: '%s'\n", command);
abort();
}
/* only one command can run at a time, so let's lock/unlock */
lock_system();
write_pipe(command_pipe_write, (char *)&len, sizeof(int));
write_pipe(command_pipe_write, command, len);
read_pipe(result_pipe_read, (char *)&res, sizeof(int));
unlock_system();
if (res == -1 || !WIFEXITED(res) || WEXITSTATUS(res) != 0) return -1;
return 0;
}
/********************************************************************/
/* start_background_system() */
/* initializes the "background system" module */
/* to be called very early by the main processing */
/********************************************************************/
void start_background_system(void) {
int p[2];
pid_t son;
if (module_initialized == 1)
return;
module_initialized = 1;
if (pipe(p) == -1) {
perror("pipe");
exit(1);
}
command_pipe_read = p[0];
command_pipe_write = p[1];
if (pipe(p) == -1) {
perror("pipe");
exit(1);
}
result_pipe_read = p[0];
result_pipe_write = p[1];
son = fork();
if (son == -1) {
perror("fork");
exit(1);
}
if (son) {
close(result_pipe_write);
close(command_pipe_read);
return;
}
close(result_pipe_read);
close(command_pipe_write);
background_system_process();
}
int rt_sleep_ns (uint64_t x)
{
struct timespec myTime;
clock_gettime(CLOCK_MONOTONIC, &myTime);
myTime.tv_sec += x/1000000000ULL;
myTime.tv_nsec = x%1000000000ULL;
if (myTime.tv_nsec>=1000000000) {
myTime.tv_nsec -= 1000000000;
myTime.tv_sec++;
}
return clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &myTime, NULL);
}
#ifdef HAVE_LIB_CAP
#include <sys/capability.h>
/* \brief reports if the current thread has capability CAP_SYS_NICE, i.e. */
bool has_cap_sys_nice(void)
{
/* get capabilities of calling PID */
cap_t cap = cap_get_pid(0);
cap_flag_value_t val;
/* check to what CAP_SYS_NICE is currently ("effective capability") set */
int ret = cap_get_flag(cap, CAP_SYS_NICE, CAP_EFFECTIVE, &val);
AssertFatal(ret == 0, "Error in cap_get_flag(): ret %d errno %d\n", ret, errno);
cap_free(cap);
/* return true if CAP_SYS_NICE is currently set */
return val == CAP_SET;
}
#else
/* libcap has not been detected on this system. We do not need to require it --
* we can try to read directly via a syscall. This is discouraged, though; from
* the man page: "The portable interfaces are cap_set_proc(3) and
* cap_get_proc(3); if possible, you should use those interfaces in
* applications". */
#include <sys/syscall.h> /* Definition of SYS_* constants */
#include <linux/capability.h> /* capabilities used below */
/* \brief reports if the current thread has capability CAP_SYS_NICE, i.e. */
bool has_cap_sys_nice(void)
{
struct __user_cap_header_struct hdr = {.version = _LINUX_CAPABILITY_VERSION_3};
struct __user_cap_data_struct cap[2];
if (syscall(SYS_capget, &hdr, cap) == -1)
return false;
return (cap[0].effective & (1 << CAP_SYS_NICE)) != 0;
}
#endif
void threadCreate(pthread_t* t, void * (*func)(void*), void * param, char* name, int affinity, int priority)
{
int ret;
bool set_prio = has_cap_sys_nice();
pthread_attr_t attr;
ret=pthread_attr_init(&attr);
AssertFatal(ret == 0, "Error in pthread_attr_init(): ret: %d, errno: %d\n", ret, errno);
if (set_prio) {
ret = pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED);
AssertFatal(ret == 0, "Error in pthread_attr_setinheritsched(): ret: %d, errno: %d\n", ret, errno);
ret = pthread_attr_setschedpolicy(&attr, SCHED_OAI);
AssertFatal(ret == 0, "Error in pthread_attr_setschedpolicy(): ret: %d, errno: %d\n", ret, errno);
AssertFatal(priority >= sched_get_priority_min(SCHED_OAI) && priority <= sched_get_priority_max(SCHED_OAI),
"Scheduling priority %d not possible: must be within [%d, %d]\n",
priority,
sched_get_priority_min(SCHED_OAI),
sched_get_priority_max(SCHED_OAI));
AssertFatal(priority <= sched_get_priority_max(SCHED_OAI), "");
struct sched_param sparam = {0};
sparam.sched_priority = priority;
ret = pthread_attr_setschedparam(&attr, &sparam);
AssertFatal(ret == 0, "Error in pthread_attr_setschedparam(): ret: %d errno: %d\n", ret, errno);
LOG_I(UTIL, "%s() for %s: creating thread with affinity %x, priority %d\n", __func__, name, affinity, priority);
} else {
affinity = -1;
priority = -1;
LOG_I(UTIL, "%s() for %s: creating thread (no affinity, default priority)\n", __func__, name);
}
ret=pthread_create(t, &attr, func, param);
AssertFatal(ret == 0, "Error in pthread_create(): ret: %d, errno: %d\n", ret, errno);
pthread_setname_np(*t, name);
if (affinity != -1 ) {
cpu_set_t cpuset;
CPU_ZERO(&cpuset);
CPU_SET(affinity, &cpuset);
ret = pthread_setaffinity_np(*t, sizeof(cpu_set_t), &cpuset);
AssertFatal(ret == 0, "Error in pthread_getaffinity_np(): ret: %d, errno: %d", ret, errno);
}
pthread_attr_destroy(&attr);
}
// Legacy, pthread_create + thread_top_init() should be replaced by threadCreate
// threadCreate encapsulates the posix pthread api
void thread_top_init(char *thread_name,
int affinity,
uint64_t runtime,
uint64_t deadline,
uint64_t period) {
int policy, s, j;
struct sched_param sparam;
char cpu_affinity[1024];
cpu_set_t cpuset;
int settingPriority = 1;
/* Set affinity mask to include CPUs 2 to MAX_CPUS */
/* CPU 0 is reserved for UHD threads */
/* CPU 1 is reserved for all RX_TX threads */
/* Enable CPU Affinity only if number of CPUs > 2 */
CPU_ZERO(&cpuset);
/* Check the actual affinity mask assigned to the thread */
s = pthread_getaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
if (s != 0)
{
perror( "pthread_getaffinity_np");
exit_fun("Error getting processor affinity ");
}
memset(cpu_affinity,0,sizeof(cpu_affinity));
for (j = 0; j < 1024; j++)
{
if (CPU_ISSET(j, &cpuset))
{
char temp[1024];
sprintf (temp, " CPU_%d", j);
strcat(cpu_affinity, temp);
}
}
if (settingPriority) {
memset(&sparam, 0, sizeof(sparam));
sparam.sched_priority = sched_get_priority_max(SCHED_FIFO);
policy = SCHED_FIFO;
s = pthread_setschedparam(pthread_self(), policy, &sparam);
if (s != 0) {
perror("pthread_setschedparam : ");
exit_fun("Error setting thread priority");
}
s = pthread_getschedparam(pthread_self(), &policy, &sparam);
if (s != 0) {
perror("pthread_getschedparam : ");
exit_fun("Error getting thread priority");
}
pthread_setname_np(pthread_self(), thread_name);
LOG_I(HW, "[SCHED][eNB] %s started on CPU %d, sched_policy = %s , priority = %d, CPU Affinity=%s \n",thread_name,sched_getcpu(),
(policy == SCHED_FIFO) ? "SCHED_FIFO" :
(policy == SCHED_RR) ? "SCHED_RR" :
(policy == SCHED_OTHER) ? "SCHED_OTHER" :
"???",
sparam.sched_priority, cpu_affinity );
}
}
/* \brief lock memory to RAM to avoid delays */
void lock_memory_to_ram(void)
{
int rc = mlockall(MCL_CURRENT | MCL_FUTURE);
if (rc != 0)
LOG_W(UTIL, "mlockall() failed: %d, %s\n", errno, strerror(errno));
}