svm: fix fifo tail/head/ooo logic for u32 wrap

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

diff --git a/src/svm/svm_fifo.h b/src/svm/svm_fifo.h
index 82d2b39..c937095 100644 (file)
--- a/src/svm/svm_fifo.h
+++ b/src/svm/svm_fifo.h
@@ -23,6 +23,7 @@
 #include <vppinfra/vec.h>
 #include <vppinfra/pool.h>
 #include <vppinfra/format.h>
+#include <vppinfra/rbtree.h>
 
 /** Out-of-order segment */
 typedef struct
@@ -38,7 +39,7 @@ typedef struct
 #define OOO_SEGMENT_INVALID_INDEX      ((u32)~0)
 #define SVM_FIFO_INVALID_SESSION_INDEX         ((u32)~0)
 #define SVM_FIFO_INVALID_INDEX         ((u32)~0)
-#define SVM_FIFO_MAX_EVT_SUBSCRIBERS   8
+#define SVM_FIFO_MAX_EVT_SUBSCRIBERS   7
 
 enum svm_fifo_tx_ntf_
 {
@@ -65,6 +66,8 @@ typedef struct svm_fifo_chunk_
 typedef enum svm_fifo_flag_
 {
   SVM_FIFO_F_SIZE_UPDATE = 1 << 0,
+  SVM_FIFO_F_MULTI_CHUNK = 1 << 1,
+  SVM_FIFO_F_LL_TRACKED = 1 << 2,
 } svm_fifo_flag_t;
 
 typedef struct _svm_fifo
@@ -76,6 +79,7 @@ typedef struct _svm_fifo
   svm_fifo_chunk_t *start_chunk;/**< first chunk in fifo chunk list */
   svm_fifo_chunk_t *end_chunk; /**< end chunk in fifo chunk list */
   svm_fifo_chunk_t *new_chunks;        /**< chunks yet to be added to list */
+  rb_tree_t chunk_lookup;
 
     CLIB_CACHE_LINE_ALIGN_MARK (shared_second);
   volatile u32 has_event;      /**< non-zero if deq event exists */
@@ -93,17 +97,18 @@ typedef struct _svm_fifo
   struct _svm_fifo *prev;      /**< prev in active chain */
 
     CLIB_CACHE_LINE_ALIGN_MARK (consumer);
-  u32 head;
+  u32 head;                    /**< fifo head position/byte */
   svm_fifo_chunk_t *head_chunk;        /**< tracks chunk where head lands */
+  svm_fifo_chunk_t *ooo_deq;   /**< last chunk used for ooo dequeue */
   volatile u32 want_tx_ntf;    /**< producer wants nudge */
   volatile u32 has_tx_ntf;
 
     CLIB_CACHE_LINE_ALIGN_MARK (producer);
-  u32 tail;
+  u32 tail;                    /**< fifo tail position/byte */
+  u32 ooos_list_head;          /**< Head of out-of-order linked-list */
   svm_fifo_chunk_t *tail_chunk;        /**< tracks chunk where tail lands */
-
+  svm_fifo_chunk_t *ooo_enq;   /**< last chunk used for ooo enqueue */
   ooo_segment_t *ooo_segments; /**< Pool of ooo segments */
-  u32 ooos_list_head;          /**< Head of out-of-order linked-list */
   u32 ooos_newest;             /**< Last segment to have been updated */
   volatile u8 n_subscribers;
   u8 subscribers[SVM_FIFO_MAX_EVT_SUBSCRIBERS];
@@ -120,11 +125,11 @@ typedef enum
   SVM_FIFO_FULL = -2,
 } svm_fifo_err_t;
 
-typedef struct svm_fifo_segment_
+typedef struct svm_fifo_seg_
 {
   u8 *data;
   u32 len;
-} svm_fifo_segment_t;
+} svm_fifo_seg_t;
 
 #if SVM_FIFO_TRACE
 #define svm_fifo_trace_add(_f, _s, _l, _t)             \
@@ -327,8 +332,48 @@ svm_fifo_unset_event (svm_fifo_t * f)
 
 svm_fifo_t *svm_fifo_create (u32 data_size_in_bytes);
 void svm_fifo_init (svm_fifo_t * f, u32 size);
+
+/**
+ * Allocate a fifo chunk on heap
+ *
+ * If the chunk is allocated on a fifo segment, this should be called
+ * with the segment's heap pushed.
+ *
+ * @param size chunk size in bytes. Will be rounded to the next highest
+ *             power-of-two
+ * @return     new chunk or 0 if alloc failed
+ */
+svm_fifo_chunk_t *svm_fifo_chunk_alloc (u32 size);
+
+/**
+ * Grow fifo size by adding chunk to chunk list
+ *
+ * If fifos are allocated on a segment, this should be called with
+ * the segment's heap pushed.
+ *
+ * @param f    fifo to be extended
+ * @param c    chunk or linked list of chunks to be added
+ */
 void svm_fifo_add_chunk (svm_fifo_t * f, svm_fifo_chunk_t * c);
 void svm_fifo_free (svm_fifo_t * f);
+/**
+ * Cleanup fifo chunk lookup rb tree
+ *
+ * The rb tree is allocated in segment heap so this should be called
+ * with it pushed.
+ *
+ * @param f    fifo to cleanup
+ */
+void svm_fifo_free_chunk_lookup (svm_fifo_t * f);
+/**
+ * Cleanup fifo ooo data
+ *
+ * The ooo data is allocated in producer process memory. The fifo
+ * segment heap should not be pushed.
+ *
+ * @param f    fifo to cleanup
+ */
+void svm_fifo_free_ooo_data (svm_fifo_t * f);
 
 int svm_fifo_enqueue_nowait (svm_fifo_t * f, u32 max_bytes,
                             const u8 * copy_from_here);
@@ -339,9 +384,9 @@ int svm_fifo_dequeue_nowait (svm_fifo_t * f, 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);
 void svm_fifo_dequeue_drop_all (svm_fifo_t * f);
-int svm_fifo_segments (svm_fifo_t * f, svm_fifo_segment_t * fs);
-void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_segment_t * fs);
-void svm_fifo_init_pointers (svm_fifo_t * f, u32 pointer);
+int svm_fifo_segments (svm_fifo_t * f, svm_fifo_seg_t * fs);
+void svm_fifo_segments_free (svm_fifo_t * f, svm_fifo_seg_t * fs);
+void svm_fifo_init_pointers (svm_fifo_t * f, u32 head, u32 tail);
 void svm_fifo_clone (svm_fifo_t * df, svm_fifo_t * sf);
 void svm_fifo_overwrite_head (svm_fifo_t * f, u8 * data, u32 len);
 void svm_fifo_add_subscriber (svm_fifo_t * f, u8 subscriber);
@@ -482,13 +527,13 @@ svm_fifo_newest_ooo_segment_reset (svm_fifo_t * f)
 always_inline u32
 ooo_segment_distance_from_tail (svm_fifo_t * f, u32 pos, u32 tail)
 {
-  return ((pos - tail) % f->size);
+  return ((f->size + pos - tail) % f->size);
 }
 
 always_inline u32
 ooo_segment_distance_to_tail (svm_fifo_t * f, u32 pos, u32 tail)
 {
-  return ((tail - pos) % f->size);
+  return ((f->size + tail - pos) % f->size);
 }
 
 always_inline u32