ipcpd: normal: Extract SDU scheduling component

This extracts the SDU scheduling component out of the Flow Manager
since the functionality was duplicated. For both the N-1 and N+1 flow
sets an SDU scheduling component is now created.

1 files changed, 131 insertions, 0 deletions

diff --git a/src/ipcpd/normal/sdu_sched.c b/src/ipcpd/normal/sdu_sched.c
new file mode 100644
index 00000000..14fc672f
--- /dev/null
+++ b/src/ipcpd/normal/sdu_sched.c
@@ -0,0 +1,131 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2017
+ *
+ * SDU scheduler component
+ *
+ *    Dimitri Staessens <dimitri.staessens@ugent.be>
+ *    Sander Vrijders   <sander.vrijders@ugent.be>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#define OUROBOROS_PREFIX "sdu-scheduler"
+
+#include <ouroboros/config.h>
+#include <ouroboros/logs.h>
+#include <ouroboros/errno.h>
+
+#include "sdu_sched.h"
+
+#include <stdbool.h>
+#include <assert.h>
+#include <stdlib.h>
+
+#define FD_UPDATE_TIMEOUT 10000 /* nanoseconds */
+
+struct sdu_sched {
+        flow_set_t * set[QOS_CUBE_MAX];
+        fqueue_t *   fqs[QOS_CUBE_MAX];
+        next_sdu_t   callback;
+        pthread_t    sdu_reader;
+};
+
+static void * sdu_reader(void * o)
+{
+        struct sdu_sched *   sched;
+        struct shm_du_buff * sdb;
+        struct timespec      timeout = {0, FD_UPDATE_TIMEOUT};
+        int                  fd;
+        int                  i = 0;
+        int                  ret;
+
+        sched = (struct sdu_sched *) o;
+
+        while (true) {
+                /* FIXME: replace with scheduling policy call */
+                i = (i + 1) % QOS_CUBE_MAX;
+
+                ret = flow_event_wait(sched->set[i], sched->fqs[i], &timeout);
+                if (ret == -ETIMEDOUT)
+                        continue;
+
+                if (ret < 0) {
+                        log_warn("Event error: %d.", ret);
+                        continue;
+                }
+
+                while ((fd = fqueue_next(sched->fqs[i])) >= 0) {
+                        if (ipcp_flow_read(fd, &sdb)) {
+                                log_warn("Failed to read SDU from fd %d.", fd);
+                                continue;
+                        }
+
+                        if (sched->callback(fd, i, sdb)) {
+                                log_warn("Callback reported an error.");
+                                continue;
+                        }
+                }
+        }
+
+        return (void *) 0;
+}
+
+struct sdu_sched * sdu_sched_create(flow_set_t * set[QOS_CUBE_MAX],
+                                    next_sdu_t   callback)
+{
+        struct sdu_sched * sdu_sched;
+        int                i;
+        int                j;
+
+        sdu_sched = malloc(sizeof(*sdu_sched));
+        if (sdu_sched == NULL)
+                return NULL;
+
+        sdu_sched->callback = callback;
+
+        for (i = 0; i < QOS_CUBE_MAX; ++i) {
+                sdu_sched->set[i] = set[i];
+
+                sdu_sched->fqs[i] = fqueue_create();
+                if (sdu_sched->fqs[i] == NULL) {
+                        for (j = i; j >= 0; --j)
+                                fqueue_destroy(sdu_sched->fqs[j]);
+                        free(sdu_sched);
+                        return NULL;
+                }
+        }
+
+        pthread_create(&sdu_sched->sdu_reader,
+                       NULL,
+                       sdu_reader,
+                       (void *) sdu_sched);
+
+        return sdu_sched;
+}
+
+void sdu_sched_destroy(struct sdu_sched * sdu_sched)
+{
+        int i;
+
+        assert(sdu_sched);
+
+        pthread_cancel(sdu_sched->sdu_reader);
+
+        pthread_join(sdu_sched->sdu_reader, NULL);
+
+        for (i = 0; i < QOS_CUBE_MAX; ++i)
+                fqueue_destroy(sdu_sched->fqs[i]);
+
+        free(sdu_sched);
+}