vlib: handoff rework

Type: improvement
Change-Id: I1e199ae31e969154319e94c5cd286b8d8adc6660
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 14 insertions, 123 deletions

diff --git a/src/vlib/threads.h b/src/vlib/threads.h
index 2dfb535c3a5..91727bacc23 100644
--- a/src/vlib/threads.h
+++ b/src/vlib/threads.h
@@ -64,20 +64,16 @@ typedef struct vlib_thread_registration_
 #define VLIB_LOG2_THREAD_STACK_SIZE (21)
 #define VLIB_THREAD_STACK_SIZE (1<<VLIB_LOG2_THREAD_STACK_SIZE)
 
-typedef enum
-{
-  VLIB_FRAME_QUEUE_ELT_DISPATCH_FRAME,
-} vlib_frame_queue_msg_type_t;
-
 typedef struct
 {
   CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
   volatile u32 valid;
-  u32 msg_type;
+  u32 maybe_trace : 1;
   u32 n_vectors;
-  u32 last_n_vectors;
+  u32 offset;
+  STRUCT_MARK (end_of_reset);
 
-  /* 256 * 4 = 1024 bytes, even mult of cache line size */
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
   u32 buffer_index[VLIB_FRAME_SIZE];
 }
 vlib_frame_queue_elt_t;
@@ -117,42 +113,29 @@ extern vlib_worker_thread_t *vlib_worker_threads;
 
 typedef struct
 {
-  /* enqueue side */
+  /* static data */
   CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
-  volatile u64 tail;
-  u32 enqueue_full_events;
-
-  /* dequeue side */
-    CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
-  volatile u64 head;
-  u64 trace;
+  vlib_frame_queue_elt_t *elts;
   u64 vector_threshold;
+  u64 trace;
+  u32 nelts;
 
-  /* dequeue hint to enqueue side */
-    CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
-  volatile u64 head_hint;
+  /* modified by enqueue side  */
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
+  volatile u64 tail;
 
-  /* read-only, constant, shared */
-    CLIB_CACHE_LINE_ALIGN_MARK (cacheline3);
-  vlib_frame_queue_elt_t *elts;
-  u32 nelts;
+  /* modified by dequeue side  */
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
+  volatile u64 head;
 }
 vlib_frame_queue_t;
 
 typedef struct
 {
-  vlib_frame_queue_elt_t **handoff_queue_elt_by_thread_index;
-  vlib_frame_queue_t **congested_handoff_queue_by_thread_index;
-} vlib_frame_queue_per_thread_data_t;
-
-typedef struct
-{
   u32 node_index;
   u32 frame_queue_nelts;
-  u32 queue_hi_thresh;
 
   vlib_frame_queue_t **vlib_frame_queues;
-  vlib_frame_queue_per_thread_data_t *per_thread_data;
 
   /* for frame queue tracing */
   frame_queue_trace_t *frame_queue_traces;
@@ -169,10 +152,6 @@ typedef struct
 /* Called early, in thread 0's context */
 clib_error_t *vlib_thread_init (vlib_main_t * vm);
 
-int vlib_frame_queue_enqueue (vlib_main_t * vm, u32 node_runtime_index,
-			      u32 frame_queue_index, vlib_frame_t * frame,
-			      vlib_frame_queue_msg_type_t type);
-
 void vlib_worker_thread_node_runtime_update (void);
 
 void vlib_create_worker_threads (vlib_main_t * vm, int n,
@@ -510,94 +489,6 @@ vlib_thread_is_main_w_barrier (void)
 	       && vlib_worker_threads->wait_at_barrier[0])));
 }
 
-static inline void
-vlib_put_frame_queue_elt (vlib_frame_queue_elt_t * hf)
-{
-  CLIB_MEMORY_BARRIER ();
-  hf->valid = 1;
-}
-
-static inline vlib_frame_queue_elt_t *
-vlib_get_frame_queue_elt (u32 frame_queue_index, u32 index)
-{
-  vlib_frame_queue_t *fq;
-  vlib_frame_queue_elt_t *elt;
-  vlib_thread_main_t *tm = &vlib_thread_main;
-  vlib_frame_queue_main_t *fqm =
-    vec_elt_at_index (tm->frame_queue_mains, frame_queue_index);
-  u64 new_tail;
-
-  fq = fqm->vlib_frame_queues[index];
-  ASSERT (fq);
-
-  new_tail = clib_atomic_add_fetch (&fq->tail, 1);
-
-  /* Wait until a ring slot is available */
-  while (new_tail >= fq->head_hint + fq->nelts)
-    vlib_worker_thread_barrier_check ();
-
-  elt = fq->elts + (new_tail & (fq->nelts - 1));
-
-  /* this would be very bad... */
-  while (elt->valid)
-    ;
-
-  elt->msg_type = VLIB_FRAME_QUEUE_ELT_DISPATCH_FRAME;
-  elt->last_n_vectors = elt->n_vectors = 0;
-
-  return elt;
-}
-
-static inline vlib_frame_queue_t *
-is_vlib_frame_queue_congested (u32 frame_queue_index,
-			       u32 index,
-			       u32 queue_hi_thresh,
-			       vlib_frame_queue_t **
-			       handoff_queue_by_worker_index)
-{
-  vlib_frame_queue_t *fq;
-  vlib_thread_main_t *tm = &vlib_thread_main;
-  vlib_frame_queue_main_t *fqm =
-    vec_elt_at_index (tm->frame_queue_mains, frame_queue_index);
-
-  fq = handoff_queue_by_worker_index[index];
-  if (fq != (vlib_frame_queue_t *) (~0))
-    return fq;
-
-  fq = fqm->vlib_frame_queues[index];
-  ASSERT (fq);
-
-  if (PREDICT_FALSE (fq->tail >= (fq->head_hint + queue_hi_thresh)))
-    {
-      /* a valid entry in the array will indicate the queue has reached
-       * the specified threshold and is congested
-       */
-      handoff_queue_by_worker_index[index] = fq;
-      fq->enqueue_full_events++;
-      return fq;
-    }
-
-  return NULL;
-}
-
-static inline vlib_frame_queue_elt_t *
-vlib_get_worker_handoff_queue_elt (u32 frame_queue_index,
-				   u32 vlib_worker_index,
-				   vlib_frame_queue_elt_t **
-				   handoff_queue_elt_by_worker_index)
-{
-  vlib_frame_queue_elt_t *elt;
-
-  if (handoff_queue_elt_by_worker_index[vlib_worker_index])
-    return handoff_queue_elt_by_worker_index[vlib_worker_index];
-
-  elt = vlib_get_frame_queue_elt (frame_queue_index, vlib_worker_index);
-
-  handoff_queue_elt_by_worker_index[vlib_worker_index] = elt;
-
-  return elt;
-}
-
 u8 *vlib_thread_stack_init (uword thread_index);
 int vlib_thread_cb_register (struct vlib_main_t *vm,
 			     vlib_thread_callbacks_t * cb);