Session layer improvements

[vpp.git] / src / svm / svm_fifo.h

diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h
index 70624b7..d67237c 100644 (file)
--- a/src/svm/svm_fifo.h
+++ b/src/svm/svm_fifo.h
@@ -23,39 +23,35 @@
 #include <vppinfra/format.h>
 #include <pthread.h>
 
-typedef enum
-{
-  SVM_FIFO_TAG_NOT_HELD = 0,
-  SVM_FIFO_TAG_DEQUEUE,
-  SVM_FIFO_TAG_ENQUEUE,
-} svm_lock_tag_t;
-
 /** Out-of-order segment */
 typedef struct
 {
   u32 next;    /**< Next linked-list element pool index */
   u32 prev;    /**< Previous linked-list element pool index */
 
-  u32 fifo_position;   /**< Start of segment, normalized*/
-  u32 length;          /**< Length of segment */
+  u32 start;   /**< Start of segment, normalized*/
+  u32 length;  /**< Length of segment */
 } ooo_segment_t;
 
+format_function_t format_ooo_segment;
+format_function_t format_ooo_list;
+
 #define OOO_SEGMENT_INVALID_INDEX ((u32)~0)
 
 typedef struct
 {
-  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 */
   u32 nitems;
+    CLIB_CACHE_LINE_ALIGN_MARK (end_cursize);
+
+  volatile u8 has_event;       /**< non-zero if deq event exists */
 
   /* Backpointers */
-  u32 server_session_index;
+  u32 master_session_index;
   u32 client_session_index;
-  u8 server_thread_index;
+  u8 master_thread_index;
   u8 client_thread_index;
+  u32 segment_manager;
     CLIB_CACHE_LINE_ALIGN_MARK (end_shared);
   u32 head;
     CLIB_CACHE_LINE_ALIGN_MARK (end_consumer);
@@ -70,30 +66,6 @@ typedef struct
     CLIB_CACHE_LINE_ALIGN_MARK (data);
 } svm_fifo_t;
 
-static inline int
-svm_fifo_lock (svm_fifo_t * f, u32 pid, u32 tag, int nowait)
-{
-  if (PREDICT_TRUE (nowait == 0))
-    pthread_mutex_lock (&f->mutex);
-  else
-    {
-      if (pthread_mutex_trylock (&f->mutex))
-       return -1;
-    }
-  f->owner_pid = pid;
-  f->tag = tag;
-  return 0;
-}
-
-static inline void
-svm_fifo_unlock (svm_fifo_t * f)
-{
-  f->owner_pid = 0;
-  f->tag = 0;
-  CLIB_MEMORY_BARRIER ();
-  pthread_mutex_unlock (&f->mutex);
-}
-
 static inline u32
 svm_fifo_max_dequeue (svm_fifo_t * f)
 {
@@ -103,7 +75,7 @@ svm_fifo_max_dequeue (svm_fifo_t * f)
 static inline u32
 svm_fifo_max_enqueue (svm_fifo_t * f)
 {
-  return f->nitems - f->cursize;
+  return f->nitems - svm_fifo_max_dequeue (f);
 }
 
 static inline u8
@@ -112,21 +84,43 @@ svm_fifo_has_ooo_data (svm_fifo_t * f)
   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);
+void svm_fifo_free (svm_fifo_t * f);
 
-int svm_fifo_enqueue_nowait (svm_fifo_t * f, int pid, u32 max_bytes,
+int svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes,
                             u8 * copy_from_here);
+int svm_fifo_enqueue_with_offset (svm_fifo_t * f, u32 offset,
+                                 u32 required_bytes, u8 * copy_from_here);
+int svm_fifo_dequeue_nowait (svm_fifo_t * f, u32 max_bytes, u8 * copy_here);
 
-int svm_fifo_enqueue_with_offset (svm_fifo_t * f, int pid,
-                                 u32 offset, u32 required_bytes,
-                                 u8 * copy_from_here);
-
-int svm_fifo_dequeue_nowait (svm_fifo_t * f, int pid, u32 max_bytes,
-                            u8 * copy_here);
+int svm_fifo_peek (svm_fifo_t * f, u32 offset, u32 max_bytes, u8 * copy_here);
+int svm_fifo_dequeue_drop (svm_fifo_t * f, u32 max_bytes);
+u32 svm_fifo_number_ooo_segments (svm_fifo_t * f);
+ooo_segment_t *svm_fifo_first_ooo_segment (svm_fifo_t * f);
 
-int svm_fifo_peek (svm_fifo_t * f, int pid, u32 offset, u32 max_bytes,
-                  u8 * copy_here);
-int svm_fifo_dequeue_drop (svm_fifo_t * f, int pid, u32 max_bytes);
+format_function_t format_svm_fifo;
 
 always_inline ooo_segment_t *
 svm_fifo_newest_ooo_segment (svm_fifo_t * f)
@@ -137,13 +131,23 @@ svm_fifo_newest_ooo_segment (svm_fifo_t * f)
 always_inline u32
 ooo_segment_offset (svm_fifo_t * f, ooo_segment_t * s)
 {
-  return ((f->nitems + s->fifo_position - f->tail) % f->nitems);
+//  return ((f->nitems + s->fifo_position - f->tail) % f->nitems);
+  return s->start;
 }
 
 always_inline u32
 ooo_segment_end_offset (svm_fifo_t * f, ooo_segment_t * s)
 {
-  return ((f->nitems + s->fifo_position + s->length - f->tail) % f->nitems);
+//  return ((f->nitems + s->fifo_position + s->length - f->tail) % f->nitems);
+  return s->start + s->length;
+}
+
+always_inline ooo_segment_t *
+ooo_segment_get_prev (svm_fifo_t * f, ooo_segment_t * s)
+{
+  if (s->prev == OOO_SEGMENT_INVALID_INDEX)
+    return 0;
+  return pool_elt_at_index (f->ooo_segments, s->prev);
 }
 
 #endif /* __included_ssvm_fifo_h__ */