svm: allow mq attachments at random offsets

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

diff --git a/src/svm/message_queue.h b/src/svm/message_queue.h
index 50f79fb..4b314b8 100644 (file)
--- a/src/svm/message_queue.h
+++ b/src/svm/message_queue.h
@@ -24,16 +24,30 @@
 #include <vppinfra/error.h>
 #include <svm/queue.h>
 
-typedef struct svm_msg_q_ring_
+typedef struct svm_msg_q_ring_shared_
 {
   volatile u32 cursize;                        /**< current size of the ring */
   u32 nitems;                          /**< max size of the ring */
   volatile u32 head;                   /**< current head (for dequeue) */
   volatile u32 tail;                   /**< current tail (for enqueue) */
   u32 elsize;                          /**< size of an element */
-  u8 *data;                            /**< chunk of memory for msg data */
+  u8 data[0];                          /**< chunk of memory for msg data */
+} svm_msg_q_ring_shared_t;
+
+typedef struct svm_msg_q_ring_
+{
+  u32 nitems;                  /**< max size of the ring */
+  u32 elsize;                  /**< size of an element */
+  svm_msg_q_ring_shared_t *shr; /**< ring in shared memory */
 } __clib_packed svm_msg_q_ring_t;
 
+typedef struct svm_msg_q_shared_
+{
+  u32 n_rings;     /**< number of rings after q */
+  u32 pad;         /**< 8 byte alignment for q */
+  svm_queue_t q[0]; /**< queue for exchanging messages */
+} __clib_packed svm_msg_q_shared_t;
+
 typedef struct svm_msg_q_
 {
   svm_queue_t *q;                      /**< queue for exchanging messages */
@@ -77,10 +91,12 @@ typedef union
  *                     ring configs
  * @return             message queue
  */
-svm_msg_q_t *svm_msg_q_alloc (svm_msg_q_cfg_t * cfg);
-svm_msg_q_t *svm_msg_q_init (void *base, svm_msg_q_cfg_t *cfg);
+svm_msg_q_shared_t *svm_msg_q_alloc (svm_msg_q_cfg_t *cfg);
+svm_msg_q_shared_t *svm_msg_q_init (void *base, svm_msg_q_cfg_t *cfg);
 uword svm_msg_q_size_to_alloc (svm_msg_q_cfg_t *cfg);
 
+void svm_msg_q_attach (svm_msg_q_t *mq, void *smq_base);
+
 /**
  * Free message queue
  *
@@ -267,8 +283,8 @@ svm_msg_q_is_full (svm_msg_q_t * mq)
 static inline u8
 svm_msg_q_ring_is_full (svm_msg_q_t * mq, u32 ring_index)
 {
-  ASSERT (ring_index < vec_len (mq->rings));
-  return (mq->rings[ring_index].cursize == mq->rings[ring_index].nitems);
+  svm_msg_q_ring_t *ring = vec_elt_at_index (mq->rings, ring_index);
+  return (ring->shr->cursize >= ring->nitems);
 }
 
 /**