lib: Shared Memory

Updated tests. Added code to drop a corner case (packet where the tail
PCI would cross the edge of the ring buffer) because solving this very
rare case is not worth the performance hit on the ringbuffer the extra
code would incur. This means the ringbuffer might drop a very small
percentage of packets.

1 files changed, 184 insertions, 0 deletions

diff --git a/src/lib/tests/shm_du_map_test.c b/src/lib/tests/shm_du_map_test.c
new file mode 100644
index 00000000..d9b44732
--- /dev/null
+++ b/src/lib/tests/shm_du_map_test.c
@@ -0,0 +1,184 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * Test of the Shared Memory Map
+ *
+ *    Dimitri Staessens <dimitri.staessens@intec.ugent.be>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <ouroboros/shm_du_map.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/mman.h>
+#include <pthread.h>
+
+#define SIZE_OF_DU_BUFF 24
+#define TEST_BUFF_SIZE (SHM_DU_BUFF_BLOCK_SIZE - SIZE_OF_DU_BUFF)
+
+#define MAX(a,b) (a > b ? a : b)
+#define MIN(a,b) (a < b ? a : b)
+
+int sync;
+
+void * produce()
+{
+        struct shm_du_map * dum;
+        long                test_buf_size = 0;
+        uint8_t           * test_values;
+        int                 headspace;
+        int                 tailspace;
+        long                i;
+        long                bytes_written = 0;
+        struct timespec     starttime;
+        struct timespec     stoptime;
+        double              elapsed;
+
+        dum = shm_du_map_open();
+        if (dum == NULL) {
+                LOG_ERR("Could not open shm.");
+                return (void *)-1;
+        }
+
+        srand(time(NULL));
+
+        test_values = malloc (sizeof *test_values * TEST_BUFF_SIZE);
+        for (i = 0; i < TEST_BUFF_SIZE; i++)
+                test_values[i] = 170;
+
+        clock_gettime(CLOCK_MONOTONIC, &starttime);
+        for (i = 1; i < SHM_BLOCKS_IN_MAP; i++) {
+                struct shm_du_buff * sdb;
+                size_t               len;
+
+                test_buf_size = TEST_BUFF_SIZE;
+
+                headspace     = 32;
+                tailspace     = 8;
+
+                len = test_buf_size - (headspace + tailspace);
+
+                sdb = shm_create_du_buff(dum,
+                                         test_buf_size,
+                                         headspace,
+                                         test_values,
+                                         len);
+
+                if (sdb != NULL) {
+                        bytes_written += len;
+                }
+                else {
+                        sync = -2;
+                        break;
+                }
+        }
+
+        clock_gettime(CLOCK_MONOTONIC, &stoptime);
+        elapsed =(stoptime.tv_sec + stoptime.tv_nsec / 1000000000.0) -
+                (starttime.tv_sec + starttime.tv_nsec / 1000000000.0);
+        LOG_INFO("%ld bytes written in %.1lf ms = %lf Gb/s",
+                 bytes_written,
+                 elapsed * 1000.0,
+                 bytes_written * 8 / (elapsed * 1000000000));
+
+        free(test_values);
+
+        sync = -1;
+
+        return 0;
+}
+
+void * consume()
+{
+        struct shm_du_map * dum;
+
+        struct timespec     ts;
+
+        ts.tv_sec = 0;
+        ts.tv_nsec = 1000000;
+
+        dum = shm_du_map_open();
+
+        if (dum == NULL) {
+                LOG_ERR("Could not open shm.");
+                return (void *)-1;
+        }
+
+        while (!sync) {
+                while (!shm_release_du_buff(dum));
+                nanosleep(&ts, NULL);
+        }
+
+        return 0;
+}
+
+int shm_du_map_test(int argc, char ** argv)
+{
+        struct shm_du_map * dum;
+        int                 res1;
+        pthread_t           producer;
+        pthread_t           consumer;
+
+        /* test 1 */
+
+        LOG_INFO("starting create/close test.");
+
+        dum = shm_du_map_create();
+
+        if (dum == NULL) {
+                LOG_ERR("Could not open shm (dum).");
+                return -1;
+        }
+
+        shm_du_map_close(dum);
+
+        LOG_INFO("done.");
+
+        /* test 2 */
+
+        LOG_INFO("starting sequential test.");
+
+        dum = shm_du_map_create();
+
+        res1 = (int) pthread_create(&producer, NULL, produce, NULL);
+        pthread_join(producer, NULL);
+
+        pthread_create(&consumer, NULL, consume, NULL);
+        pthread_join(consumer, NULL);
+
+        shm_du_map_close(dum);
+
+        LOG_INFO("done.");
+
+        /* test 3 */
+
+        LOG_INFO("starting concurrency test.");
+
+        dum = shm_du_map_create();
+
+        res1 = (int) pthread_create(&producer, NULL, produce, NULL);
+        pthread_create(&consumer, NULL, consume, NULL);
+
+        pthread_join(producer, NULL);
+        pthread_join(consumer, NULL);
+
+        shm_du_map_close(dum);
+
+        LOG_INFO("done.");
+
+        return res1;
+}