{
pthread_mutex_t mutex; /* 8 bytes */
pthread_cond_t condvar; /* 8 bytes */
- u32 owner_pid;
svm_lock_tag_t tag;
- volatile u32 cursize;
+
+ volatile u32 cursize; /**< current fifo size */
+ volatile u8 has_event; /**< non-zero if deq event exists */
+ u32 owner_pid;
u32 nitems;
/* Backpointers */
return f->ooos_list_head != OOO_SEGMENT_INVALID_INDEX;
}
+/**
+ * Sets fifo event flag.
+ *
+ * @return 1 if flag was not set.
+ */
+always_inline u8
+svm_fifo_set_event (svm_fifo_t * f)
+{
+ /* Probably doesn't need to be atomic. Still, better avoid surprises */
+ return __sync_lock_test_and_set (&f->has_event, 1) == 0;
+}
+
+/**
+ * Unsets fifo event flag.
+ */
+always_inline void
+svm_fifo_unset_event (svm_fifo_t * f)
+{
+ /* Probably doesn't need to be atomic. Still, better avoid surprises */
+ __sync_lock_test_and_set (&f->has_event, 0);
+}
+
svm_fifo_t *svm_fifo_create (u32 data_size_in_bytes);
int svm_fifo_enqueue_nowait (svm_fifo_t * f, int pid, u32 max_bytes,