diff mbox series

[v3,08/19] gro: remove use of VLAs for Windows built code

Message ID 1715019531-22796-9-git-send-email-roretzla@linux.microsoft.com (mailing list archive)
State New
Delegated to: Thomas Monjalon
Headers
Series remove use of VLAs for Windows |

Checks

Context Check Description
ci/checkpatch success coding style OK

Commit Message

Tyler Retzlaff May 6, 2024, 6:18 p.m. UTC 
  MSVC does not support VLAs, replace VLAs with standard C arrays
or alloca(). alloca() is available for all toolchain/platform
combinations officially supported by DPDK.

Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
---
 lib/gro/rte_gro.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Stephen Hemminger May 7, 2024, 12:47 a.m. UTC | #1 
On Mon,  6 May 2024 11:18:40 -0700
Tyler Retzlaff <roretzla@linux.microsoft.com> wrote:

> MSVC does not support VLAs, replace VLAs with standard C arrays
> or alloca(). alloca() is available for all toolchain/platform
> combinations officially supported by DPDK.
> 
> Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
> ---
>  lib/gro/rte_gro.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/gro/rte_gro.c b/lib/gro/rte_gro.c
> index d824eeb..0f9e85c 100644
> --- a/lib/gro/rte_gro.c
> +++ b/lib/gro/rte_gro.c
> @@ -179,7 +179,7 @@ struct gro_ctx {
>  	struct gro_vxlan_udp4_item vxlan_udp_items[RTE_GRO_MAX_BURST_ITEM_NUM]
>  			= {{{0}} };
>  
> -	struct rte_mbuf *unprocess_pkts[nb_pkts];
> +	struct rte_mbuf **unprocess_pkts = alloca(sizeof(struct rte_mbuf *) * nb_pkts);
>  	uint32_t item_num;
>  	int32_t ret;
>  	uint16_t i, unprocess_num = 0, nb_after_gro = nb_pkts;
> @@ -360,7 +360,7 @@ struct gro_ctx {
>  		uint16_t nb_pkts,
>  		void *ctx)
>  {
> -	struct rte_mbuf *unprocess_pkts[nb_pkts];
> +	struct rte_mbuf **unprocess_pkts = alloca(sizeof(struct rte_mbuf *) * nb_pkts);
>  	struct gro_ctx *gro_ctx = ctx;
>  	void *tcp_tbl, *udp_tbl, *vxlan_tcp_tbl, *vxlan_udp_tbl, *tcp6_tbl;
>  	uint64_t current_time;


According to rte_gro.h the maximum supported burst size is

#define RTE_GRO_MAX_BURST_ITEM_NUM 128U
/**< the max number of packets that rte_gro_reassemble_burst()
 
And it looks like the code already truncates at that.
diff mbox series

Patch

diff --git a/lib/gro/rte_gro.c b/lib/gro/rte_gro.c
index d824eeb..0f9e85c 100644
--- a/lib/gro/rte_gro.c
+++ b/lib/gro/rte_gro.c
@@ -179,7 +179,7 @@  struct gro_ctx {
 	struct gro_vxlan_udp4_item vxlan_udp_items[RTE_GRO_MAX_BURST_ITEM_NUM]
 			= {{{0}} };
 
-	struct rte_mbuf *unprocess_pkts[nb_pkts];
+	struct rte_mbuf **unprocess_pkts = alloca(sizeof(struct rte_mbuf *) * nb_pkts);
 	uint32_t item_num;
 	int32_t ret;
 	uint16_t i, unprocess_num = 0, nb_after_gro = nb_pkts;
@@ -360,7 +360,7 @@  struct gro_ctx {
 		uint16_t nb_pkts,
 		void *ctx)
 {
-	struct rte_mbuf *unprocess_pkts[nb_pkts];
+	struct rte_mbuf **unprocess_pkts = alloca(sizeof(struct rte_mbuf *) * nb_pkts);
 	struct gro_ctx *gro_ctx = ctx;
 	void *tcp_tbl, *udp_tbl, *vxlan_tcp_tbl, *vxlan_udp_tbl, *tcp6_tbl;
 	uint64_t current_time;