mempool: use actual IOVA addresses when populating

Currently, when mempool is being populated, we get IOVA address
of every segment using rte_mem_virt2iova(). This works for internal
memory, but does not really work for external memory, and does not
work on platforms which return RTE_BAD_IOVA as a result of this
call (such as FreeBSD). Moreover, even when it works, the function
in question will do unnecessary pagewalks in IOVA as PA mode, as
it falls back to rte_mem_virt2phy() instead of just doing a lookup in
internal memseg table.

To fix it, replace the call to first attempt to look through the
internal memseg table (this takes care of internal and external memory),
and fall back to rte_mem_virt2iova() when unable to perform VA->IOVA
translation via memseg table.

Fixes: 66cc45e293ed ("mem: replace memseg with memseg lists")
Cc: stable@dpdk.org
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
Tested-by: Bo Chen <box.c.chen@intel.com>

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 40cae3e..8da2e47 100644 (file)
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -356,6 +356,19 @@ fail:
        return ret;
 }
 
+static rte_iova_t
+get_iova(void *addr)
+{
+       struct rte_memseg *ms;
+
+       /* try registered memory first */
+       ms = rte_mem_virt2memseg(addr, NULL);
+       if (ms == NULL || ms->iova == RTE_BAD_IOVA)
+               /* fall back to actual physical address */
+               return rte_mem_virt2iova(addr);
+       return ms->iova + RTE_PTR_DIFF(addr, ms->addr);
+}
+
 /* Populate the mempool with a virtual area. Return the number of
  * objects added, or a negative value on error.
  */
@@ -375,7 +388,7 @@ rte_mempool_populate_virt(struct rte_mempool *mp, char *addr,
        for (off = 0; off < len &&
                     mp->populated_size < mp->size; off += phys_len) {
 
-               iova = rte_mem_virt2iova(addr + off);
+               iova = get_iova(addr + off);
 
                if (iova == RTE_BAD_IOVA && rte_eal_has_hugepages()) {
                        ret = -EINVAL;
@@ -391,7 +404,7 @@ rte_mempool_populate_virt(struct rte_mempool *mp, char *addr,
                     phys_len = RTE_MIN(phys_len + pg_sz, len - off)) {
                        rte_iova_t iova_tmp;
 
-                       iova_tmp = rte_mem_virt2iova(addr + off + phys_len);
+                       iova_tmp = get_iova(addr + off + phys_len);
 
                        if (iova_tmp == RTE_BAD_IOVA ||
                                        iova_tmp != iova + phys_len)