1 files changed, 88 insertions, 5 deletions

diff --git a/lib/librte_eal/common/malloc_elem.c b/lib/librte_eal/common/malloc_elem.c
index 9bfe9b9b..e0a8ed15 100644
--- a/lib/librte_eal/common/malloc_elem.c
+++ b/lib/librte_eal/common/malloc_elem.c
@@ -18,10 +18,89 @@
 #include <rte_common.h>
 #include <rte_spinlock.h>
 
+#include "eal_internal_cfg.h"
 #include "eal_memalloc.h"
 #include "malloc_elem.h"
 #include "malloc_heap.h"
 
+size_t
+malloc_elem_find_max_iova_contig(struct malloc_elem *elem, size_t align)
+{
+	void *cur_page, *contig_seg_start, *page_end, *cur_seg_end;
+	void *data_start, *data_end;
+	rte_iova_t expected_iova;
+	struct rte_memseg *ms;
+	size_t page_sz, cur, max;
+
+	page_sz = (size_t)elem->msl->page_sz;
+	data_start = RTE_PTR_ADD(elem, MALLOC_ELEM_HEADER_LEN);
+	data_end = RTE_PTR_ADD(elem, elem->size - MALLOC_ELEM_TRAILER_LEN);
+	/* segment must start after header and with specified alignment */
+	contig_seg_start = RTE_PTR_ALIGN_CEIL(data_start, align);
+
+	/* if we're in IOVA as VA mode, or if we're in legacy mode with
+	 * hugepages, all elements are IOVA-contiguous.
+	 */
+	if (rte_eal_iova_mode() == RTE_IOVA_VA ||
+			(internal_config.legacy_mem && rte_eal_has_hugepages()))
+		return RTE_PTR_DIFF(data_end, contig_seg_start);
+
+	cur_page = RTE_PTR_ALIGN_FLOOR(contig_seg_start, page_sz);
+	ms = rte_mem_virt2memseg(cur_page, elem->msl);
+
+	/* do first iteration outside the loop */
+	page_end = RTE_PTR_ADD(cur_page, page_sz);
+	cur_seg_end = RTE_MIN(page_end, data_end);
+	cur = RTE_PTR_DIFF(cur_seg_end, contig_seg_start) -
+			MALLOC_ELEM_TRAILER_LEN;
+	max = cur;
+	expected_iova = ms->iova + page_sz;
+	/* memsegs are contiguous in memory */
+	ms++;
+
+	cur_page = RTE_PTR_ADD(cur_page, page_sz);
+
+	while (cur_page < data_end) {
+		page_end = RTE_PTR_ADD(cur_page, page_sz);
+		cur_seg_end = RTE_MIN(page_end, data_end);
+
+		/* reset start of contiguous segment if unexpected iova */
+		if (ms->iova != expected_iova) {
+			/* next contiguous segment must start at specified
+			 * alignment.
+			 */
+			contig_seg_start = RTE_PTR_ALIGN(cur_page, align);
+			/* new segment start may be on a different page, so find
+			 * the page and skip to next iteration to make sure
+			 * we're not blowing past data end.
+			 */
+			ms = rte_mem_virt2memseg(contig_seg_start, elem->msl);
+			cur_page = ms->addr;
+			/* don't trigger another recalculation */
+			expected_iova = ms->iova;
+			continue;
+		}
+		/* cur_seg_end ends on a page boundary or on data end. if we're
+		 * looking at data end, then malloc trailer is already included
+		 * in the calculations. if we're looking at page end, then we
+		 * know there's more data past this page and thus there's space
+		 * for malloc element trailer, so don't count it here.
+		 */
+		cur = RTE_PTR_DIFF(cur_seg_end, contig_seg_start);
+		/* update max if cur value is bigger */
+		if (cur > max)
+			max = cur;
+
+		/* move to next page */
+		cur_page = page_end;
+		expected_iova = ms->iova + page_sz;
+		/* memsegs are contiguous in memory */
+		ms++;
+	}
+
+	return max;
+}
+
 /*
  * Initialize a general malloc_elem header structure
  */
@@ -386,16 +465,18 @@ malloc_elem_join_adjacent_free(struct malloc_elem *elem)
 	if (elem->next != NULL && elem->next->state == ELEM_FREE &&
 			next_elem_is_adjacent(elem)) {
 		void *erase;
+		size_t erase_len;
 
 		/* we will want to erase the trailer and header */
 		erase = RTE_PTR_SUB(elem->next, MALLOC_ELEM_TRAILER_LEN);
+		erase_len = MALLOC_ELEM_OVERHEAD + elem->next->pad;
 
 		/* remove from free list, join to this one */
 		malloc_elem_free_list_remove(elem->next);
 		join_elem(elem, elem->next);
 
-		/* erase header and trailer */
-		memset(erase, 0, MALLOC_ELEM_OVERHEAD);
+		/* erase header, trailer and pad */
+		memset(erase, 0, erase_len);
 	}
 
 	/*
@@ -406,9 +487,11 @@ malloc_elem_join_adjacent_free(struct malloc_elem *elem)
 			prev_elem_is_adjacent(elem)) {
 		struct malloc_elem *new_elem;
 		void *erase;
+		size_t erase_len;
 
 		/* we will want to erase trailer and header */
 		erase = RTE_PTR_SUB(elem, MALLOC_ELEM_TRAILER_LEN);
+		erase_len = MALLOC_ELEM_OVERHEAD + elem->pad;
 
 		/* remove from free list, join to this one */
 		malloc_elem_free_list_remove(elem->prev);
@@ -416,8 +499,8 @@ malloc_elem_join_adjacent_free(struct malloc_elem *elem)
 		new_elem = elem->prev;
 		join_elem(new_elem, elem);
 
-		/* erase header and trailer */
-		memset(erase, 0, MALLOC_ELEM_OVERHEAD);
+		/* erase header, trailer and pad */
+		memset(erase, 0, erase_len);
 
 		elem = new_elem;
 	}
@@ -436,7 +519,7 @@ malloc_elem_free(struct malloc_elem *elem)
 	void *ptr;
 	size_t data_len;
 
-	ptr = RTE_PTR_ADD(elem, sizeof(*elem));
+	ptr = RTE_PTR_ADD(elem, MALLOC_ELEM_HEADER_LEN);
 	data_len = elem->size - MALLOC_ELEM_OVERHEAD;
 
 	elem = malloc_elem_join_adjacent_free(elem);