Adding internal-only function to find biggest free IOVA-contiguous
malloc element. This is not exposed to external API.
Signed-off-by: Anatoly Burakov <anatoly.bura...@intel.com>
Acked-by: Remy Horton <remy.hor...@intel.com>
Acked-by: Shreyansh Jain <shreyansh.j...@nxp.com>
---
Notes:
v6:
- Patch was postponed to 18.08 but i forgot to add
deprecation notice for the API changes, so
these external malloc stats API changes have been
dropped from this patchset
v4:
- Fix comments to be more up to date with v4 code
- Add comments explaining trailer handling
v2:
- Add header to newly recalculated element start
v2:
- Add header to newly recalculated element start
lib/librte_eal/common/malloc_elem.c | 79 +++++++++++++++++++++++++++++
lib/librte_eal/common/malloc_elem.h | 6 +++
2 files changed, 85 insertions(+)
diff --git a/lib/librte_eal/common/malloc_elem.c
b/lib/librte_eal/common/malloc_elem.c
index 9bfe9b9b4..f1bb4fee7 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
*/
diff --git a/lib/librte_eal/common/malloc_elem.h
b/lib/librte_eal/common/malloc_elem.h
index 7331af9ca..e2bda4c02 100644
--- a/lib/librte_eal/common/malloc_elem.h
+++ b/lib/librte_eal/common/malloc_elem.h
@@ -179,4 +179,10 @@ malloc_elem_free_list_index(size_t size);
void
malloc_elem_free_list_insert(struct malloc_elem *elem);
+/*
+ * Find biggest IOVA-contiguous zone within an element with specified
alignment.
+ */
+size_t
+malloc_elem_find_max_iova_contig(struct malloc_elem *elem, size_t align);
+
#endif /* MALLOC_ELEM_H_ */
--
2.17.0
