[dpdk-stable] [PATCH 1/1] net/i40e: fix compilation failure on core-avx-i

[Lu, Wenzhuo]

Hi Shahed,



> -----Original Message-----

> From: Shahed Shaikh <shaikh at niometrics.com<mailto:shaikh at niometrics.com>>

> Sent: Tuesday, June 22, 2021 5:37 PM

> To: Xing, Beilei <beilei.xing at intel.com<mailto:beilei.xing at intel.com>>

> Cc: dev at dpdk.org<mailto:dev at dpdk.org>; Shahed Shaikh <shaikh at niometrics.com<mailto:shaikh at niometrics.com>>;

> stable at dpdk.org<mailto:stable at dpdk.org>

> Subject: [PATCH 1/1] net/i40e: fix compilation failure on core-avx-i

>

> i40e_rxtx_vec_sse.c fails to compile with below configuration:

> - #define RTE_LIBRTE_I40E_16BYTE_RX_DESC 1 in config/rte_config.h

> - cpu=core-axv-i

> - gcc which supports -mavx2 (e.g. gcc 4.8.5)

>

> This is because commit 0604b1f2208f ("net/i40e: fix crash in AVX512")

> added

> i40e_rxq_rearm_common() to i40e_rxtx_vec_common.h which is included by

> i40e_rxtx_vec_sse.c.

>

> This function is enabled for compilation if CC_AVX2_SUPPORT is defined.

> As per drivers/net/i40e/meson.build, CC_AVX2_SUPPORT is defined when

> either CPU supports __AVX2__ or compiler supports -mavx2 option.

>

> So for given configuration, CC_AVX2_SUPPORT gets defined but we don't

> pass -mavx2 explicitly to gcc while compiling i40e_rxtx_vec_sse.c.

Looks like it's better and more clear if a new specific avx head file is added.

Just want to understand more about the problem. I don't see the same problem when using 'gcc version 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC)', don't understand why -mavx2 is missing.

And more, if so, why the avx2 code doesn't meet the same problem?

Thanks.



> Hence it fails due to avx2 specific code from i40e_rxq_rearm_command().

>

> This patch tries to fix the compilation by moving

> i40e_rxq_rearm_common() to a new header file which will only be

> included by i40e_rxtx_vec_avx2.c and i40e_rxtx_vec_avx512.c.

>

> Fixes: 0604b1f2208f ("net/i40e: fix crash in AVX512")

> Cc: stable at dpdk.org<mailto:stable at dpdk.org>

>

> Signed-off-by: Shahed Shaikh <shaikh at niometrics.com<mailto:shaikh at niometrics.com>>