mempool: fix pages computation to determine number of objects

In rte_mempool_obj_iter(), when element boundary coincides with page boundary,
even if a single page is required per object, a loop checks that the next page
is contiguous and drops the first one otherwise.
This commit checks subsequent pages only when several are required per object.

Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Reviewed-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index d1a02a2..190cfd9 100644 (file)
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -156,7 +156,7 @@ rte_mempool_obj_iter(void *vaddr, uint32_t elt_num, size_t elt_sz, size_t align,
        rte_mempool_obj_iter_t obj_iter, void *obj_iter_arg)
 {
        uint32_t i, j, k;
-       uint32_t pgn;
+       uint32_t pgn, pgf;
        uintptr_t end, start, va;
        uintptr_t pg_sz;
 
@@ -171,10 +171,14 @@ rte_mempool_obj_iter(void *vaddr, uint32_t elt_num, size_t elt_sz, size_t align,
                start = RTE_ALIGN_CEIL(va, align);
                end = start + elt_sz;
 
-               pgn = (end >> pg_shift) - (start >> pg_shift);
+               /* index of the first page for the next element. */
+               pgf = (end >> pg_shift) - (start >> pg_shift);
+
+               /* index of the last page for the current element. */
+               pgn = ((end - 1) >> pg_shift) - (start >> pg_shift);
                pgn += j;
 
-               /* do we have enough space left for the next element. */
+               /* do we have enough space left for the element. */
                if (pgn >= pg_num)
                        break;
 
@@ -194,7 +198,7 @@ rte_mempool_obj_iter(void *vaddr, uint32_t elt_num, size_t elt_sz, size_t align,
                                obj_iter(obj_iter_arg, (void *)start,
                                        (void *)end, i);
                        va = end;
-                       j = pgn;
+                       j += pgf;
                        i++;
                } else {
                        va = RTE_ALIGN_CEIL((va + 1), pg_sz);