mem: improve best-effort allocation

[dpdk.git] / lib / librte_eal / linux / eal / eal_memalloc.c

diff --git a/lib/librte_eal/linux/eal/eal_memalloc.c b/lib/librte_eal/linux/eal/eal_memalloc.c
index b6fb183..14c3ea8 100644 (file)
--- a/lib/librte_eal/linux/eal/eal_memalloc.c
+++ b/lib/librte_eal/linux/eal/eal_memalloc.c
@@ -874,10 +874,32 @@ 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_next_n_free(&cur_msl->memseg_arr, 0, need);
-       if (cur_idx < 0)
-               return 0;
-       start_idx = cur_idx;
+       if (wa->exact) {
+               /* if we require exact number of pages in a list, find them */
+               cur_idx = rte_fbarray_find_next_n_free(&cur_msl->memseg_arr, 0,
+                               need);
+               if (cur_idx < 0)
+                       return 0;
+               start_idx = cur_idx;
+       } else {
+               int cur_len;
+
+               /* we don't require exact number of pages, so we're going to go
+                * for best-effort allocation. that means finding the biggest
+                * unused block, and going with that.
+                */
+               cur_idx = rte_fbarray_find_biggest_free(&cur_msl->memseg_arr,
+                               0);
+               if (cur_idx < 0)
+                       return 0;
+               start_idx = cur_idx;
+               /* adjust the size to possibly be smaller than original
+                * request, but do not allow it to be bigger.
+                */
+               cur_len = rte_fbarray_find_contig_free(&cur_msl->memseg_arr,
+                               cur_idx);
+               need = RTE_MIN(need, (unsigned int)cur_len);
+       }
 
        /* do not allow any page allocations during the time we're allocating,
         * because file creation and locking operations are not atomic,
@@ -954,7 +976,8 @@ out:
                cur_msl->version++;
        if (dir_fd >= 0)
                close(dir_fd);
-       return 1;
+       /* if we didn't allocate any segments, move on to the next list */
+       return i > 0;
 }
 
 struct free_walk_param {