ceph/src/dpdk/lib/librte_eal/linuxapp/eal/eal_thread.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <errno.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <stdint.h>
  38 #include <unistd.h>
  39 #include <pthread.h>
  40 #include <sched.h>
  41 #include <sys/queue.h>
  42 #include <sys/syscall.h>
  43
  44 #include <rte_debug.h>
  45 #include <rte_atomic.h>
  46 #include <rte_launch.h>
  47 #include <rte_log.h>
  48 #include <rte_memory.h>
  49 #include <rte_memzone.h>
  50 #include <rte_per_lcore.h>
  51 #include <rte_eal.h>
  52 #include <rte_per_lcore.h>
  53 #include <rte_lcore.h>
  54
  55 #include "eal_private.h"
  56 #include "eal_thread.h"
  57
  58 RTE_DEFINE_PER_LCORE(unsigned, _lcore_id) = LCORE_ID_ANY;
  59 RTE_DEFINE_PER_LCORE(unsigned, _socket_id) = (unsigned)SOCKET_ID_ANY;
  60 RTE_DEFINE_PER_LCORE(rte_cpuset_t, _cpuset);
  61
  62 /*
  63  * Send a message to a slave lcore identified by slave_id to call a
  64  * function f with argument arg. Once the execution is done, the
  65  * remote lcore switch in FINISHED state.
  66  */
  67 int
  68 rte_eal_remote_launch(int (*f)(void *), void *arg, unsigned slave_id)
  69 {
  70         int n;
  71         char c = 0;
  72         int m2s = lcore_config[slave_id].pipe_master2slave[1];
  73         int s2m = lcore_config[slave_id].pipe_slave2master[0];
  74
  75         if (lcore_config[slave_id].state != WAIT)
  76                 return -EBUSY;
  77
  78         lcore_config[slave_id].f = f;
  79         lcore_config[slave_id].arg = arg;
  80
  81         /* send message */
  82         n = 0;
  83         while (n == 0 || (n < 0 && errno == EINTR))
  84                 n = write(m2s, &c, 1);
  85         if (n < 0)
  86                 rte_panic("cannot write on configuration pipe\n");
  87
  88         /* wait ack */
  89         do {
  90                 n = read(s2m, &c, 1);
  91         } while (n < 0 && errno == EINTR);
  92
  93         if (n <= 0)
  94                 rte_panic("cannot read on configuration pipe\n");
  95
  96         return 0;
  97 }
  98
  99 /* set affinity for current EAL thread */
 100 static int
 101 eal_thread_set_affinity(void)
 102 {
 103         unsigned lcore_id = rte_lcore_id();
 104
 105         /* acquire system unique id  */
 106         rte_gettid();
 107
 108         /* update EAL thread core affinity */
 109         return rte_thread_set_affinity(&lcore_config[lcore_id].cpuset);
 110 }
 111
 112 void eal_thread_init_master(unsigned lcore_id)
 113 {
 114         /* set the lcore ID in per-lcore memory area */
 115         RTE_PER_LCORE(_lcore_id) = lcore_id;
 116
 117         /* set CPU affinity */
 118         if (eal_thread_set_affinity() < 0)
 119                 rte_panic("cannot set affinity\n");
 120 }
 121
 122 /* main loop of threads */
 123 __attribute__((noreturn)) void *
 124 eal_thread_loop(__attribute__((unused)) void *arg)
 125 {
 126         char c;
 127         int n, ret;
 128         unsigned lcore_id;
 129         pthread_t thread_id;
 130         int m2s, s2m;
 131         char cpuset[RTE_CPU_AFFINITY_STR_LEN];
 132
 133         thread_id = pthread_self();
 134
 135         /* retrieve our lcore_id from the configuration structure */
 136         RTE_LCORE_FOREACH_SLAVE(lcore_id) {
 137                 if (thread_id == lcore_config[lcore_id].thread_id)
 138                         break;
 139         }
 140         if (lcore_id == RTE_MAX_LCORE)
 141                 rte_panic("cannot retrieve lcore id\n");
 142
 143         m2s = lcore_config[lcore_id].pipe_master2slave[0];
 144         s2m = lcore_config[lcore_id].pipe_slave2master[1];
 145
 146         /* set the lcore ID in per-lcore memory area */
 147         RTE_PER_LCORE(_lcore_id) = lcore_id;
 148
 149         /* set CPU affinity */
 150         if (eal_thread_set_affinity() < 0)
 151                 rte_panic("cannot set affinity\n");
 152
 153         ret = eal_thread_dump_affinity(cpuset, RTE_CPU_AFFINITY_STR_LEN);
 154
 155         RTE_LOG(DEBUG, EAL, "lcore %u is ready (tid=%x;cpuset=[%s%s])\n",
 156                 lcore_id, (int)thread_id, cpuset, ret == 0 ? "" : "...");
 157
 158         /* read on our pipe to get commands */
 159         while (1) {
 160                 void *fct_arg;
 161
 162                 /* wait command */
 163                 do {
 164                         n = read(m2s, &c, 1);
 165                 } while (n < 0 && errno == EINTR);
 166
 167                 if (n <= 0)
 168                         rte_panic("cannot read on configuration pipe\n");
 169
 170                 lcore_config[lcore_id].state = RUNNING;
 171
 172                 /* send ack */
 173                 n = 0;
 174                 while (n == 0 || (n < 0 && errno == EINTR))
 175                         n = write(s2m, &c, 1);
 176                 if (n < 0)
 177                         rte_panic("cannot write on configuration pipe\n");
 178
 179                 if (lcore_config[lcore_id].f == NULL)
 180                         rte_panic("NULL function pointer\n");
 181
 182                 /* call the function and store the return value */
 183                 fct_arg = lcore_config[lcore_id].arg;
 184                 ret = lcore_config[lcore_id].f(fct_arg);
 185                 lcore_config[lcore_id].ret = ret;
 186                 rte_wmb();
 187                 lcore_config[lcore_id].state = FINISHED;
 188         }
 189
 190         /* never reached */
 191         /* pthread_exit(NULL); */
 192         /* return NULL; */
 193 }
 194
 195 /* require calling thread tid by gettid() */
 196 int rte_sys_gettid(void)
 197 {
 198         return (int)syscall(SYS_gettid);
 199 }
 200
 201 int rte_thread_setname(pthread_t id, const char *name)
 202 {
 203         int ret = -1;
 204 #if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
 205 #if __GLIBC_PREREQ(2, 12)
 206         ret = pthread_setname_np(id, name);
 207 #endif
 208 #endif
 209         RTE_SET_USED(id);
 210         RTE_SET_USED(name);
 211         return ret;
 212 }