From: Cyril Chemparathy <cchemparathy@ezchip.com>
To: dev@dpdk.org
Subject: [dpdk-dev] [PATCH v4 7/9] librte_mbuf: Add rte_pktmbuf_mtod_offset()
Date: Mon, 22 Jun 2015 11:34:21 -0700 [thread overview]
Message-ID: <1434998063-15739-8-git-send-email-cchemparathy@ezchip.com> (raw)
In-Reply-To: <1434998063-15739-1-git-send-email-cchemparathy@ezchip.com>
There are a number of instances in the code where rte_pktmbuf_mtod()
is used to get the mbuf data pointer, only to add an offset before
casting the result to some other header type. This patch adds a new
rte_pktmbuf_mtod_offset() macro to eliminate these awful double cast
situations.
Change-Id: I4dec35a15e44a7b8c767559a8d3b294177f39552
Signed-off-by: Cyril Chemparathy <cchemparathy@ezchip.com>
---
lib/librte_mbuf/rte_mbuf.h | 24 +++++++++++++++++++++---
1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 6efd2b5..396963c 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -54,6 +54,7 @@
*/
#include <stdint.h>
+#include <rte_common.h>
#include <rte_mempool.h>
#include <rte_memory.h>
#include <rte_atomic.h>
@@ -1080,18 +1081,35 @@ static inline struct rte_mbuf *rte_pktmbuf_lastseg(struct rte_mbuf *m)
}
/**
+ * A macro that points to an offset into the data in the mbuf.
+ *
+ * The returned pointer is cast to type t. Before using this
+ * function, the user must ensure that the first segment is large
+ * enough to accomodate its data.
+ *
+ * @param m
+ * The packet mbuf.
+ * @param o
+ * The offset into the mbuf data.
+ * @param t
+ * The type to cast the result into.
+ */
+#define rte_pktmbuf_mtod_offset(m, t, o) \
+ ((t)((char *)(m)->buf_addr + (m)->data_off + (o)))
+
+/**
* A macro that points to the start of the data in the mbuf.
*
* The returned pointer is cast to type t. Before using this
- * function, the user must ensure that m_headlen(m) is large enough to
- * read its data.
+ * function, the user must ensure that the first segment is large
+ * enough to accomodate its data.
*
* @param m
* The packet mbuf.
* @param t
* The type to cast the result into.
*/
-#define rte_pktmbuf_mtod(m, t) ((t)((char *)(m)->buf_addr + (m)->data_off))
+#define rte_pktmbuf_mtod(m, t) rte_pktmbuf_mtod_offset(m, t, 0)
/**
* A macro that returns the length of the packet.
--
2.1.2
next prev parent reply other threads:[~2015-06-22 18:34 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-22 18:34 [dpdk-dev] [PATCH v4 0/9] Improve cast alignment for strict aligned machines Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 1/9] mempool: silence -Wcast-align on pointer arithmetic Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 2/9] mbuf: " Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 3/9] ethdev: " Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 4/9] hash: " Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 5/9] eal: add and use unaligned integer types Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 6/9] app/test-pmd: pack simple_gre_hdr Cyril Chemparathy
2015-06-22 18:34 ` Cyril Chemparathy [this message]
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 8/9] librte_mbuf: Add transform for rte_pktmbuf_mtod_offset() Cyril Chemparathy
2015-06-22 18:34 ` [dpdk-dev] [PATCH v4 9/9] librte_mbuf: Apply mtod-offset.cocci transform Cyril Chemparathy
2015-06-23 15:36 ` [dpdk-dev] [PATCH v4 0/9] Improve cast alignment for strict aligned machines Olivier MATZ
2015-06-23 17:36 ` Cyril Chemparathy
2015-06-24 10:04 ` Thomas Monjalon
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