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40 #include <sys/types.h>
42 #include <sys/queue.h>
50 #include <rte_config.h>
51 #include <rte_common.h>
52 #include <rte_lcore.h>
53 #include <rte_per_lcore.h>
54 #include <rte_timer.h>
56 #include "lthread_api.h"
57 #include "lthread_diag_api.h"
58 #include "pthread_shim.h"
61 #define HELLOW_WORLD_MAX_LTHREADS 10
63 __thread int print_count;
64 __thread pthread_mutex_t print_lock;
66 __thread pthread_mutex_t exit_lock;
67 __thread pthread_cond_t exit_cond;
70 * A simple thread that demonstrates use of a mutex, a condition
71 * variable, thread local storage, explicit yield, and thread exit.
73 * The thread uses a mutex to protect a shared counter which is incremented
74 * and then it waits on condition variable before exiting.
76 * The thread argument is stored in and retrieved from TLS, using
77 * the pthread key create, get and set specific APIs.
79 * The thread yields while holding the mutex, to provide opportunity
80 * for other threads to contend.
82 * All of the pthread API functions used by this thread are actually
83 * resolved to corresponding lthread functions by the pthread shim
84 * implemented in pthread_shim.c
86 void *helloworld_pthread(void *arg);
87 void *helloworld_pthread(void *arg)
91 /* create a key for TLS */
92 pthread_key_create(&key, NULL);
94 /* store the arg in TLS */
95 pthread_setspecific(key, arg);
97 /* grab lock and increment shared counter */
98 pthread_mutex_lock(&print_lock);
101 /* yield thread to give opportunity for lock contention */
104 /* retrieve arg from TLS */
105 uint64_t thread_no = (uint64_t) pthread_getspecific(key);
107 printf("Hello - lcore = %d count = %d thread_no = %d thread_id = %p\n",
111 (void *)pthread_self());
113 /* release the lock */
114 pthread_mutex_unlock(&print_lock);
117 * wait on condition variable
120 pthread_mutex_lock(&exit_lock);
121 pthread_cond_wait(&exit_cond, &exit_lock);
122 pthread_mutex_unlock(&exit_lock);
125 pthread_exit((void *) thread_no);
130 * This is the initial thread
132 * It demonstrates pthread, mutex and condition variable creation,
133 * broadcast and pthread join APIs.
135 * This initial thread must always start life as an lthread.
137 * This thread creates many more threads then waits a short time
138 * before signalling them to exit using a broadcast.
140 * All of the pthread API functions used by this thread are actually
141 * resolved to corresponding lthread functions by the pthread shim
142 * implemented in pthread_shim.c
144 * After all threads have finished the lthread scheduler is shutdown
145 * and normal pthread operation is restored
147 __thread pthread_t tid[HELLOW_WORLD_MAX_LTHREADS];
149 static void initial_lthread(void *args);
150 static void initial_lthread(void *args __attribute__((unused)))
152 int lcore = (int) rte_lcore_id();
155 * We can now enable pthread API override
156 * and start to use the pthread APIs
158 pthread_override_set(1);
162 /* initialize mutex for shared counter */
164 pthread_mutex_init(&print_lock, NULL);
166 /* initialize mutex and condition variable controlling thread exit */
167 pthread_mutex_init(&exit_lock, NULL);
168 pthread_cond_init(&exit_cond, NULL);
170 /* spawn a number of threads */
171 for (i = 0; i < HELLOW_WORLD_MAX_LTHREADS; i++) {
174 * Not strictly necessary but
175 * for the sake of this example
176 * use an attribute to pass the desired lcore
182 CPU_SET(lcore, &cpuset);
183 pthread_attr_init(&attr);
184 pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &cpuset);
186 /* create the thread */
187 pthread_create(&tid[i], &attr, helloworld_pthread, (void *) i);
190 /* wait for 1s to allow threads
191 * to block on the condition variable
192 * N.B. nanosleep() is resolved to lthread_sleep()
195 struct timespec time;
199 nanosleep(&time, NULL);
201 /* wake up all the threads */
202 pthread_cond_broadcast(&exit_cond);
204 /* wait for them to finish */
205 for (i = 0; i < HELLOW_WORLD_MAX_LTHREADS; i++) {
209 pthread_join(tid[i], (void *) &thread_no);
211 printf("error on thread exit\n");
214 /* shutdown the lthread scheduler */
215 lthread_scheduler_shutdown(rte_lcore_id());
221 /* This thread creates a single initial lthread
222 * and then runs the scheduler
223 * An instance of this thread is created on each thread
227 lthread_scheduler(void *args);
229 lthread_scheduler(void *args __attribute__((unused)))
231 /* create initial thread */
234 lthread_create(<, -1, initial_lthread, (void *) NULL);
236 /* run the lthread scheduler */
239 /* restore genuine pthread operation */
240 pthread_override_set(0);
244 int main(int argc, char **argv)
248 /* basic DPDK initialization is all that is necessary to run lthreads*/
249 int ret = rte_eal_init(argc, argv);
252 rte_exit(EXIT_FAILURE, "Invalid EAL parameters\n");
254 /* enable timer subsystem */
255 rte_timer_subsystem_init();
258 lthread_diagnostic_set_mask(LT_DIAG_ALL);
261 /* create a scheduler on every core in the core mask
262 * and launch an initial lthread that will spawn many more.
266 for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
267 if (rte_lcore_is_enabled(lcore_id))
271 /* set the number of schedulers, this forces all schedulers synchronize
272 * before entering their main loop
274 lthread_num_schedulers_set(num_sched);
276 /* launch all threads */
277 rte_eal_mp_remote_launch(lthread_scheduler, (void *)NULL, CALL_MASTER);
279 /* wait for threads to stop */
280 RTE_LCORE_FOREACH_SLAVE(lcore_id) {
281 rte_eal_wait_lcore(lcore_id);