mem: revert reversed allocation

A few regressions with virtio/vhost have been discovered, due to the
strong dependency of virtio/vhost on the underlying memory layout.
Specifically, virtio/vhost share all memory pages starting from the
beginning of the segment, while the patch below made it so that the
memory is always allocated from the top of VA space, not from the
bottom.

Fixes: 179f916e88e4 ("mem: allocate in reverse to reduce fragmentation")
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

diff --git a/lib/librte_eal/linuxapp/eal/eal_memalloc.c b/lib/librte_eal/linuxapp/eal/eal_memalloc.c
index a59f229cd40a52845f94c56bdca1aac2eb3a8a42..aa95551a8f98a6aae36b07aaa7681c9a0915cbb2 100644 (file)
--- a/lib/librte_eal/linuxapp/eal/eal_memalloc.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memalloc.c
@@ -731,8 +731,7 @@ alloc_seg_walk(const struct rte_memseg_list *msl, void *arg)
        need = wa->n_segs;
 
        /* try finding space in memseg list */
-       cur_idx = rte_fbarray_find_prev_n_free(&cur_msl->memseg_arr,
-                       cur_msl->memseg_arr.len - 1, need);
+       cur_idx = rte_fbarray_find_next_n_free(&cur_msl->memseg_arr, 0, need);
        if (cur_idx < 0)
                return 0;
        start_idx = cur_idx;