mempool: get memory size with unspecified page size

Update rte_mempool_xmem_size() so that when the page_shift argument is
set to 0, assume that memory is physically contiguous, allowing to
ignore page boundaries. This will be used in the next commits.

By the way, rename the variable 'n' as 'obj_per_page' and avoid the
affectation inside the if().

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 0d18511e5b9fa88af90712eb77455cd4cdc1a76a..d5278b478e30a744440483439dadf6ab87c90f39 100644 (file)
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -253,18 +253,18 @@ rte_mempool_calc_obj_size(uint32_t elt_size, uint32_t flags,
 size_t
 rte_mempool_xmem_size(uint32_t elt_num, size_t total_elt_sz, uint32_t pg_shift)
 {
-       size_t n, pg_num, pg_sz, sz;
+       size_t obj_per_page, pg_num, pg_sz;
 
-       pg_sz = (size_t)1 << pg_shift;
+       if (pg_shift == 0)
+               return total_elt_sz * elt_num;
 
-       if ((n = pg_sz / total_elt_sz) > 0) {
-               pg_num = (elt_num + n - 1) / n;
-               sz = pg_num << pg_shift;
-       } else {
-               sz = RTE_ALIGN_CEIL(total_elt_sz, pg_sz) * elt_num;
-       }
+       pg_sz = (size_t)1 << pg_shift;
+       obj_per_page = pg_sz / total_elt_sz;
+       if (obj_per_page == 0)
+               return RTE_ALIGN_CEIL(total_elt_sz, pg_sz) * elt_num;
 
-       return sz;
+       pg_num = (elt_num + obj_per_page - 1) / obj_per_page;
+       return pg_num << pg_shift;
 }
 
 /*

diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index 0f900a1bde83263854d93286b339b8c4feac0332..53275e44ba23797d5aca67c0906caca3b8ebc387 100644 (file)
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -1261,7 +1261,7 @@ uint32_t rte_mempool_calc_obj_size(uint32_t elt_size, uint32_t flags,
  *   The size of each element, including header and trailer, as returned
  *   by rte_mempool_calc_obj_size().
  * @param pg_shift
- *   LOG2 of the physical pages size.
+ *   LOG2 of the physical pages size. If set to 0, ignore page boundaries.
  * @return
  *   Required memory size aligned at page boundary.
  */