mempool: introduce helpers for populate and required size

[dpdk.git] / lib / librte_mempool / rte_mempool_ops_default.c

diff --git a/lib/librte_mempool/rte_mempool_ops_default.c b/lib/librte_mempool/rte_mempool_ops_default.c
index 57295f7..0bfc634 100644 (file)
--- a/lib/librte_mempool/rte_mempool_ops_default.c
+++ b/lib/librte_mempool/rte_mempool_ops_default.c
@@ -7,40 +7,73 @@
 #include <rte_mempool.h>
 
 ssize_t
-rte_mempool_op_calc_mem_size_default(const struct rte_mempool *mp,
-                                    uint32_t obj_num, uint32_t pg_shift,
-                                    size_t *min_chunk_size, size_t *align)
+rte_mempool_op_calc_mem_size_helper(const struct rte_mempool *mp,
+                               uint32_t obj_num, uint32_t pg_shift,
+                               size_t *min_chunk_size, size_t *align)
 {
-       unsigned int mp_flags;
-       int ret;
        size_t total_elt_sz;
+       size_t obj_per_page, pg_sz, objs_in_last_page;
        size_t mem_size;
 
-       /* Get mempool capabilities */
-       mp_flags = 0;
-       ret = rte_mempool_ops_get_capabilities(mp, &mp_flags);
-       if ((ret < 0) && (ret != -ENOTSUP))
-               return ret;
-
        total_elt_sz = mp->header_size + mp->elt_size + mp->trailer_size;
+       if (total_elt_sz == 0) {
+               mem_size = 0;
+       } else if (pg_shift == 0) {
+               mem_size = total_elt_sz * obj_num;
+       } else {
+               pg_sz = (size_t)1 << pg_shift;
+               obj_per_page = pg_sz / total_elt_sz;
+               if (obj_per_page == 0) {
+                       /*
+                        * Note that if object size is bigger than page size,
+                        * then it is assumed that pages are grouped in subsets
+                        * of physically continuous pages big enough to store
+                        * at least one object.
+                        */
+                       mem_size =
+                               RTE_ALIGN_CEIL(total_elt_sz, pg_sz) * obj_num;
+               } else {
+                       /* In the best case, the allocator will return a
+                        * page-aligned address. For example, with 5 objs,
+                        * the required space is as below:
+                        *  |     page0     |     page1     |  page2 (last) |
+                        *  |obj0 |obj1 |xxx|obj2 |obj3 |xxx|obj4|
+                        *  <------------- mem_size ------------->
+                        */
+                       objs_in_last_page = ((obj_num - 1) % obj_per_page) + 1;
+                       /* room required for the last page */
+                       mem_size = objs_in_last_page * total_elt_sz;
+                       /* room required for other pages */
+                       mem_size += ((obj_num - objs_in_last_page) /
+                               obj_per_page) << pg_shift;
 
-       mem_size = rte_mempool_xmem_size(obj_num, total_elt_sz, pg_shift,
-                                        mp->flags | mp_flags);
-
-       if (mp_flags & MEMPOOL_F_CAPA_PHYS_CONTIG)
-               *min_chunk_size = mem_size;
-       else
-               *min_chunk_size = RTE_MAX((size_t)1 << pg_shift, total_elt_sz);
+                       /* In the worst case, the allocator returns a
+                        * non-aligned pointer, wasting up to
+                        * total_elt_sz. Add a margin for that.
+                        */
+                        mem_size += total_elt_sz - 1;
+               }
+       }
 
-       *align = RTE_MAX((size_t)RTE_CACHE_LINE_SIZE, (size_t)1 << pg_shift);
+       *min_chunk_size = total_elt_sz;
+       *align = RTE_CACHE_LINE_SIZE;
 
        return mem_size;
 }
 
+ssize_t
+rte_mempool_op_calc_mem_size_default(const struct rte_mempool *mp,
+                               uint32_t obj_num, uint32_t pg_shift,
+                               size_t *min_chunk_size, size_t *align)
+{
+       return rte_mempool_op_calc_mem_size_helper(mp, obj_num, pg_shift,
+                                               min_chunk_size, align);
+}
+
 int
-rte_mempool_op_populate_default(struct rte_mempool *mp, unsigned int max_objs,
-               void *vaddr, rte_iova_t iova, size_t len,
-               rte_mempool_populate_obj_cb_t *obj_cb, void *obj_cb_arg)
+rte_mempool_op_populate_helper(struct rte_mempool *mp, unsigned int max_objs,
+                       void *vaddr, rte_iova_t iova, size_t len,
+                       rte_mempool_populate_obj_cb_t *obj_cb, void *obj_cb_arg)
 {
        size_t total_elt_sz;
        size_t off;
@@ -60,3 +93,13 @@ rte_mempool_op_populate_default(struct rte_mempool *mp, unsigned int max_objs,
 
        return i;
 }
+
+int
+rte_mempool_op_populate_default(struct rte_mempool *mp, unsigned int max_objs,
+                               void *vaddr, rte_iova_t iova, size_t len,
+                               rte_mempool_populate_obj_cb_t *obj_cb,
+                               void *obj_cb_arg)
+{
+       return rte_mempool_op_populate_helper(mp, max_objs, vaddr, iova,
+                                       len, obj_cb, obj_cb_arg);
+}