ceph/src/spdk/dpdk/lib/librte_eal/linux/eal_thread.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation
   3  */
   4
   5 #include <errno.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <stdint.h>
   9 #include <unistd.h>
  10 #include <pthread.h>
  11 #include <sched.h>
  12 #include <sys/queue.h>
  13 #include <sys/syscall.h>
  14
  15 #include <rte_debug.h>
  16 #include <rte_atomic.h>
  17 #include <rte_launch.h>
  18 #include <rte_log.h>
  19 #include <rte_memory.h>
  20 #include <rte_per_lcore.h>
  21 #include <rte_eal.h>
  22 #include <rte_lcore.h>
  23 #include <rte_eal_trace.h>
  24
  25 #include "eal_private.h"
  26 #include "eal_thread.h"
  27
  28 RTE_DEFINE_PER_LCORE(unsigned, _lcore_id) = LCORE_ID_ANY;
  29 RTE_DEFINE_PER_LCORE(unsigned, _socket_id) = (unsigned)SOCKET_ID_ANY;
  30 RTE_DEFINE_PER_LCORE(rte_cpuset_t, _cpuset);
  31
  32 /*
  33  * Send a message to a slave lcore identified by slave_id to call a
  34  * function f with argument arg. Once the execution is done, the
  35  * remote lcore switch in FINISHED state.
  36  */
  37 int
  38 rte_eal_remote_launch(int (*f)(void *), void *arg, unsigned slave_id)
  39 {
  40         int n;
  41         char c = 0;
  42         int m2s = lcore_config[slave_id].pipe_master2slave[1];
  43         int s2m = lcore_config[slave_id].pipe_slave2master[0];
  44         int rc = -EBUSY;
  45
  46         if (lcore_config[slave_id].state != WAIT)
  47                 goto finish;
  48
  49         lcore_config[slave_id].f = f;
  50         lcore_config[slave_id].arg = arg;
  51
  52         /* send message */
  53         n = 0;
  54         while (n == 0 || (n < 0 && errno == EINTR))
  55                 n = write(m2s, &c, 1);
  56         if (n < 0)
  57                 rte_panic("cannot write on configuration pipe\n");
  58
  59         /* wait ack */
  60         do {
  61                 n = read(s2m, &c, 1);
  62         } while (n < 0 && errno == EINTR);
  63
  64         if (n <= 0)
  65                 rte_panic("cannot read on configuration pipe\n");
  66
  67         rc = 0;
  68 finish:
  69         rte_eal_trace_thread_remote_launch(f, arg, slave_id, rc);
  70         return rc;
  71 }
  72
  73 /* set affinity for current EAL thread */
  74 static int
  75 eal_thread_set_affinity(void)
  76 {
  77         unsigned lcore_id = rte_lcore_id();
  78
  79         /* acquire system unique id  */
  80         rte_gettid();
  81
  82         /* update EAL thread core affinity */
  83         return rte_thread_set_affinity(&lcore_config[lcore_id].cpuset);
  84 }
  85
  86 void eal_thread_init_master(unsigned lcore_id)
  87 {
  88         /* set the lcore ID in per-lcore memory area */
  89         RTE_PER_LCORE(_lcore_id) = lcore_id;
  90
  91         /* set CPU affinity */
  92         if (eal_thread_set_affinity() < 0)
  93                 rte_panic("cannot set affinity\n");
  94 }
  95
  96 /* main loop of threads */
  97 __rte_noreturn void *
  98 eal_thread_loop(__rte_unused void *arg)
  99 {
 100         char c;
 101         int n, ret;
 102         unsigned lcore_id;
 103         pthread_t thread_id;
 104         int m2s, s2m;
 105         char cpuset[RTE_CPU_AFFINITY_STR_LEN];
 106
 107         thread_id = pthread_self();
 108
 109         /* retrieve our lcore_id from the configuration structure */
 110         RTE_LCORE_FOREACH_SLAVE(lcore_id) {
 111                 if (thread_id == lcore_config[lcore_id].thread_id)
 112                         break;
 113         }
 114         if (lcore_id == RTE_MAX_LCORE)
 115                 rte_panic("cannot retrieve lcore id\n");
 116
 117         m2s = lcore_config[lcore_id].pipe_master2slave[0];
 118         s2m = lcore_config[lcore_id].pipe_slave2master[1];
 119
 120         /* set the lcore ID in per-lcore memory area */
 121         RTE_PER_LCORE(_lcore_id) = lcore_id;
 122
 123         /* set CPU affinity */
 124         if (eal_thread_set_affinity() < 0)
 125                 rte_panic("cannot set affinity\n");
 126
 127         ret = eal_thread_dump_affinity(cpuset, sizeof(cpuset));
 128
 129         RTE_LOG(DEBUG, EAL, "lcore %u is ready (tid=%zx;cpuset=[%s%s])\n",
 130                 lcore_id, (uintptr_t)thread_id, cpuset, ret == 0 ? "" : "...");
 131
 132         __rte_trace_mem_per_thread_alloc();
 133         rte_eal_trace_thread_lcore_ready(lcore_id, cpuset);
 134
 135         /* read on our pipe to get commands */
 136         while (1) {
 137                 void *fct_arg;
 138
 139                 /* wait command */
 140                 do {
 141                         n = read(m2s, &c, 1);
 142                 } while (n < 0 && errno == EINTR);
 143
 144                 if (n <= 0)
 145                         rte_panic("cannot read on configuration pipe\n");
 146
 147                 lcore_config[lcore_id].state = RUNNING;
 148
 149                 /* send ack */
 150                 n = 0;
 151                 while (n == 0 || (n < 0 && errno == EINTR))
 152                         n = write(s2m, &c, 1);
 153                 if (n < 0)
 154                         rte_panic("cannot write on configuration pipe\n");
 155
 156                 if (lcore_config[lcore_id].f == NULL)
 157                         rte_panic("NULL function pointer\n");
 158
 159                 /* call the function and store the return value */
 160                 fct_arg = lcore_config[lcore_id].arg;
 161                 ret = lcore_config[lcore_id].f(fct_arg);
 162                 lcore_config[lcore_id].ret = ret;
 163                 rte_wmb();
 164
 165                 /* when a service core returns, it should go directly to WAIT
 166                  * state, because the application will not lcore_wait() for it.
 167                  */
 168                 if (lcore_config[lcore_id].core_role == ROLE_SERVICE)
 169                         lcore_config[lcore_id].state = WAIT;
 170                 else
 171                         lcore_config[lcore_id].state = FINISHED;
 172         }
 173
 174         /* never reached */
 175         /* pthread_exit(NULL); */
 176         /* return NULL; */
 177 }
 178
 179 /* require calling thread tid by gettid() */
 180 int rte_sys_gettid(void)
 181 {
 182         return (int)syscall(SYS_gettid);
 183 }
 184
 185 int rte_thread_setname(pthread_t id, const char *name)
 186 {
 187         int ret = ENOSYS;
 188 #if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
 189 #if __GLIBC_PREREQ(2, 12)
 190         ret = pthread_setname_np(id, name);
 191 #endif
 192 #endif
 193         RTE_SET_USED(id);
 194         RTE_SET_USED(name);
 195         return -ret;
 196 }
 197
 198 int rte_thread_getname(pthread_t id, char *name, size_t len)
 199 {
 200         int ret = ENOSYS;
 201 #if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
 202 #if __GLIBC_PREREQ(2, 12)
 203         ret = pthread_getname_np(id, name, len);
 204 #endif
 205 #endif
 206         RTE_SET_USED(id);
 207         RTE_SET_USED(name);
 208         RTE_SET_USED(len);
 209         return -ret;
 210
 211 }