- struct log_history *hist_buf = NULL;
- static const unsigned hist_buf_size = LOG_ELT_SIZE - sizeof(*hist_buf);
- void *obj;
-
- if (history_enabled == 0)
- return 0;
-
- rte_spinlock_lock(&log_list_lock);
-
- /* get a buffer for adding in history */
- if (log_history_size > RTE_LOG_HISTORY) {
- hist_buf = STAILQ_FIRST(&log_history);
- if (hist_buf) {
- STAILQ_REMOVE_HEAD(&log_history, next);
- log_history_size--;
- }
- }
- else {
- if (rte_mempool_mc_get(log_history_mp, &obj) < 0)
- obj = NULL;
- hist_buf = obj;
- }
-
- /* no buffer */
- if (hist_buf == NULL) {
- rte_spinlock_unlock(&log_list_lock);
- return -ENOBUFS;
- }
-
- /* not enough room for msg, buffer go back in mempool */
- if (size >= hist_buf_size) {
- rte_mempool_mp_put(log_history_mp, hist_buf);
- rte_spinlock_unlock(&log_list_lock);
- return -ENOBUFS;
- }
-
- /* add in history */
- memcpy(hist_buf->buf, buf, size);
- hist_buf->buf[size] = hist_buf->buf[hist_buf_size-1] = '\0';
- hist_buf->size = size;
- STAILQ_INSERT_TAIL(&log_history, hist_buf, next);
- log_history_size++;
- rte_spinlock_unlock(&log_list_lock);
-