[dpdk-dev] [PATCH v5 6/8] mempool: detect physical contiguous object in pool

[Santosh Shukla]

The memory area containing all the objects must be physically
contiguous.
Introducing MEMPOOL_F_CAPA_PHYS_CONTIG flag for such use-case.

The flag useful to detect whether pool area has sufficient space
to fit all objects. If not then return -ENOSPC.
This way, we make sure that all object within a pool is contiguous.

Signed-off-by: Santosh Shukla <santosh.shukla at caviumnetworks.com>
Signed-off-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>
---
v4 --> v5:
- Pulled example api description mentioned by Olivier, I find it
  more correct description as used that as is in the patch.
Refer [1].
[1] http://dpdk.org/dev/patchwork/patch/27599/

 lib/librte_mempool/rte_mempool.c | 10 ++++++++++
 lib/librte_mempool/rte_mempool.h |  6 ++++++
 2 files changed, 16 insertions(+)

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 3c4a096b7..103fbd0ed 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -369,6 +369,16 @@ rte_mempool_populate_phys(struct rte_mempool *mp, char *vaddr,
 
 	total_elt_sz = mp->header_size + mp->elt_size + mp->trailer_size;
 
+	/* Detect pool area has sufficient space for elements */
+	if (mp->flags & MEMPOOL_F_CAPA_PHYS_CONTIG) {
+		if (len < total_elt_sz * mp->size) {
+			RTE_LOG(ERR, MEMPOOL,
+				"pool area %" PRIx64 " not enough\n",
+				(uint64_t)len);
+			return -ENOSPC;
+		}
+	}
+
 	memhdr = rte_zmalloc("MEMPOOL_MEMHDR", sizeof(*memhdr), 0);
 	if (memhdr == NULL)
 		return -ENOMEM;
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index 4fb538962..63688faff 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -265,6 +265,12 @@ struct rte_mempool {
 #define MEMPOOL_F_SC_GET         0x0008 /**< Default get is "single-consumer".*/
 #define MEMPOOL_F_POOL_CREATED   0x0010 /**< Internal: pool is created. */
 #define MEMPOOL_F_NO_PHYS_CONTIG 0x0020 /**< Don't need physically contiguous objs. */
+/**
+ * This capability flag is advertised by a mempool handler, if the whole
+ * memory area containing the objects must be physically contiguous.
+ * Note: This flag should not be passed by application.
+ */
+#define MEMPOOL_F_CAPA_PHYS_CONTIG 0x0040
 
 /**
  * @internal When debug is enabled, store some statistics.
-- 
2.11.0