svm: allow indirect fifo data chunks

Fifos can use multiple memory chunks for simple read/write operations.
Adding/removing chunks after assignment not yet supported.

Change-Id: I2aceab6aea78059d74e0d3a9993c40d5196d077b
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 24 insertions, 25 deletions

diff --git a/src/svm/svm_fifo_segment.c b/src/svm/svm_fifo_segment.c
index 94bf6a5e73e..90bf593f74c 100644
--- a/src/svm/svm_fifo_segment.c
+++ b/src/svm/svm_fifo_segment.c
@@ -16,6 +16,23 @@
 #include <svm/svm_fifo_segment.h>
 
 static void
+fifo_init_for_segment (svm_fifo_segment_header_t * fsh, u8 * fifo_space,
+		       u32 size, u32 freelist_index)
+{
+  svm_fifo_t *f;
+
+  f = (svm_fifo_t *) fifo_space;
+  f->freelist_index = freelist_index;
+  f->default_chunk.next = &f->default_chunk;
+  f->default_chunk.start_byte = 0;
+  f->default_chunk.length = size;
+  f->head_chunk = &f->default_chunk;
+  f->tail_chunk = &f->default_chunk;
+  f->next = fsh->free_fifos[freelist_index];
+  fsh->free_fifos[freelist_index] = f;
+}
+
+static void
 allocate_new_fifo_chunk (svm_fifo_segment_header_t * fsh,
 			 u32 data_size_in_bytes, int chunk_size)
 {
@@ -43,14 +60,11 @@ allocate_new_fifo_chunk (svm_fifo_segment_header_t * fsh,
     return;
 
   /* Carve fifo space */
-  f = (svm_fifo_t *) fifo_space;
   for (i = 0; i < chunk_size; i++)
     {
-      f->freelist_index = freelist_index;
-      f->next = fsh->free_fifos[freelist_index];
-      fsh->free_fifos[freelist_index] = f;
+      fifo_init_for_segment (fsh, fifo_space, rounded_data_size,
+			     freelist_index);
       fifo_space += sizeof (*f) + rounded_data_size;
-      f = (svm_fifo_t *) fifo_space;
     }
 }
 
@@ -149,24 +163,18 @@ svm_fifo_segment_preallocate_fifo_pairs (svm_fifo_segment_private_t * s,
     }
 
   /* Carve rx fifo space */
-  f = (svm_fifo_t *) rx_fifo_space;
   for (i = 0; i < pairs_to_allocate; i++)
     {
-      f->freelist_index = rx_freelist_index;
-      f->next = fsh->free_fifos[rx_freelist_index];
-      fsh->free_fifos[rx_freelist_index] = f;
+      fifo_init_for_segment (fsh, rx_fifo_space, rx_rounded_data_size,
+			     rx_freelist_index);
       rx_fifo_space += sizeof (*f) + rx_rounded_data_size;
-      f = (svm_fifo_t *) rx_fifo_space;
     }
   /* Carve tx fifo space */
-  f = (svm_fifo_t *) tx_fifo_space;
   for (i = 0; i < pairs_to_allocate; i++)
     {
-      f->freelist_index = tx_freelist_index;
-      f->next = fsh->free_fifos[tx_freelist_index];
-      fsh->free_fifos[tx_freelist_index] = f;
+      fifo_init_for_segment (fsh, tx_fifo_space, tx_rounded_data_size,
+			     tx_freelist_index);
       tx_fifo_space += sizeof (*f) + tx_rounded_data_size;
-      f = (svm_fifo_t *) tx_fifo_space;
     }
 
   /* Account for the pairs allocated */
@@ -381,16 +389,7 @@ svm_fifo_segment_alloc_fifo (svm_fifo_segment_private_t * fs,
 	  fsh->free_fifos[freelist_index] = f->next;
 	  /* (re)initialize the fifo, as in svm_fifo_create */
 	  clib_memset (f, 0, sizeof (*f));
-	  f->size = (1 << (max_log2 (data_size_in_bytes)));
-	  /*
-	   * usable size of the fifo set to rounded_data_size - 1
-	   * to differentiate between free fifo and empty fifo.
-	   */
-	  f->nitems = f->size - 1;
-	  f->ooos_list_head = OOO_SEGMENT_INVALID_INDEX;
-	  f->ct_session_index = SVM_FIFO_INVALID_SESSION_INDEX;
-	  f->refcnt = 1;
-	  f->freelist_index = freelist_index;
+	  svm_fifo_init (f, data_size_in_bytes);
 	  goto found;
 	}
       break;