Imported Upstream version 16.07-rc1

[deb_dpdk.git] / examples / l2fwd-keepalive / shm.c

diff --git a/examples/l2fwd-keepalive/shm.c b/examples/l2fwd-keepalive/shm.c
new file mode 100644 (file)
index 0000000..177aa5b
--- /dev/null
+++ b/examples/l2fwd-keepalive/shm.c
@@ -0,0 +1,131 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2016 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <time.h>
+
+#include <rte_common.h>
+#include <rte_log.h>
+#include <rte_keepalive.h>
+
+#include "shm.h"
+
+struct rte_keepalive_shm *rte_keepalive_shm_create(void)
+{
+       int fd;
+       int idx_core;
+       struct rte_keepalive_shm *ka_shm;
+
+       /* If any existing object is not unlinked, it makes it all too easy
+        * for clients to end up with stale shared memory blocks when
+        * restarted. Unlinking makes sure subsequent shm_open by clients
+        * will get the new block mapped below.
+        */
+       if (shm_unlink(RTE_KEEPALIVE_SHM_NAME) == -1 && errno != ENOENT)
+               printf("Warning: Error unlinking stale %s (%s)\n",
+                       RTE_KEEPALIVE_SHM_NAME, strerror(errno));
+
+       fd = shm_open(RTE_KEEPALIVE_SHM_NAME,
+               O_CREAT | O_TRUNC | O_RDWR, 0666);
+       if (fd < 0)
+               RTE_LOG(INFO, EAL,
+                       "Failed to open %s as SHM (%s)\n",
+                       RTE_KEEPALIVE_SHM_NAME,
+                       strerror(errno));
+       else if (ftruncate(fd, sizeof(struct rte_keepalive_shm)) != 0)
+               RTE_LOG(INFO, EAL,
+                       "Failed to resize SHM (%s)\n", strerror(errno));
+       else {
+               ka_shm = (struct rte_keepalive_shm *) mmap(
+                       0, sizeof(struct rte_keepalive_shm),
+                       PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+               close(fd);
+               if (ka_shm == MAP_FAILED)
+                       RTE_LOG(INFO, EAL,
+                               "Failed to mmap SHM (%s)\n", strerror(errno));
+               else {
+                       memset(ka_shm, 0, sizeof(struct rte_keepalive_shm));
+
+                       /* Initialize the semaphores for IPC/SHM use */
+                       if (sem_init(&ka_shm->core_died, 1, 0) != 0) {
+                               RTE_LOG(INFO, EAL,
+                                       "Failed to setup SHM semaphore (%s)\n",
+                                       strerror(errno));
+                               munmap(ka_shm,
+                                       sizeof(struct rte_keepalive_shm));
+                               return NULL;
+                       }
+
+                       /* Set all cores to 'not present' */
+                       for (idx_core = 0;
+                                       idx_core < RTE_KEEPALIVE_MAXCORES;
+                                       idx_core++) {
+                               ka_shm->core_state[idx_core] =
+                                       RTE_KA_STATE_UNUSED;
+                               ka_shm->core_last_seen_times[idx_core] = 0;
+                       }
+
+                       return ka_shm;
+               }
+       }
+return NULL;
+}
+
+void rte_keepalive_relayed_state(struct rte_keepalive_shm *shm,
+       const int id_core, const enum rte_keepalive_state core_state,
+       __rte_unused uint64_t last_alive)
+{
+       int count;
+
+       shm->core_state[id_core] = core_state;
+       shm->core_last_seen_times[id_core] = last_alive;
+
+       if (core_state == RTE_KEEPALIVE_SHM_DEAD) {
+               /* Since core has died, also signal ka_agent.
+                *
+                * Limit number of times semaphore can be incremented, in case
+                * ka_agent is not active.
+                */
+               if (sem_getvalue(&shm->core_died, &count) == -1) {
+                       RTE_LOG(INFO, EAL, "Semaphore check failed(%s)\n",
+                               strerror(errno));
+                       return;
+               }
+               if (count > 1)
+                       return;
+
+               if (sem_post(&shm->core_died) != 0)
+                       RTE_LOG(INFO, EAL,
+                               "Failed to increment semaphore (%s)\n",
+                               strerror(errno));
+       }
+}