From: Jan Viktorin <viktorin@rehivetech.com>
To: Jianbo Liu <jianbo.liu@linaro.org>
Cc: dev@dpdk.org, Thomas Monjalon <thomas.monjalon@6wind.com>,
Jerin Jacob <jerin.jacob@caviumnetworks.com>,
tomaszx.kulasek@intel.com
Subject: Re: [dpdk-dev] [PATCH v3 4/4] eal/arm: introduce CONFIG_RTE_ARCH_ARM_NEON_MEMCPY
Date: Mon, 21 Mar 2016 13:21:31 +0100 [thread overview]
Message-ID: <20160321132131.5d5f0354@pcviktorin.fit.vutbr.cz> (raw)
In-Reply-To: <CAP4Qi38HUkbgkPNnYAxR95Cmzu-B+gKFdz8Xj4fRBaunijsqyA@mail.gmail.com>
On Mon, 21 Mar 2016 13:42:31 +0800
Jianbo Liu <jianbo.liu@linaro.org> wrote:
> On 20 March 2016 at 03:58, Jan Viktorin <viktorin@rehivetech.com> wrote:
> > The flag is used to enable memcpy optimizations in EAL. As it is not always
> > the performance benefit, the flag allows to disable it.
> >
> > Signed-off-by: Jan Viktorin <viktorin@rehivetech.com>
> > ---
> > config/defconfig_arm-armv7a-linuxapp-gcc | 1 +
> > lib/librte_eal/common/include/arch/arm/rte_memcpy_32.h | 8 ++++++--
> > 2 files changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/config/defconfig_arm-armv7a-linuxapp-gcc b/config/defconfig_arm-armv7a-linuxapp-gcc
> > index 96c3343..2c60c2c 100644
> > --- a/config/defconfig_arm-armv7a-linuxapp-gcc
> > +++ b/config/defconfig_arm-armv7a-linuxapp-gcc
> > @@ -36,6 +36,7 @@ CONFIG_RTE_ARCH="arm"
> > CONFIG_RTE_ARCH_ARM=y
> > CONFIG_RTE_ARCH_ARMv7=y
> > CONFIG_RTE_ARCH_ARM_TUNE="cortex-a9"
> > +CONFIG_RTE_ARCH_ARM_NEON_MEMCPY=y
> >
> If it's not always benefit, why not disable here since it is common
> armv7a config, and enable in your or other user's own config file?
Jianbo, you are right. In that case, I'd just turn it off by default.
And when there is a new platform-specific defconfig, it can enable it.
Anyway, I am thinking of adding some comment into the rte_memcpy_32.h
file describing the potential of the NEON code. What about:
/* Enable in your defconfig to accelerate memcpy operations. Consider
enabling this for Cortex-A15. For Cortex-A7 and Cortex-A9, It might
accelerate short data copies (< 64 B). */
Thomas, do you consider this enough?
Jan
>
> Thanks!
> Jianbo
--
Jan Viktorin E-mail: Viktorin@RehiveTech.com
System Architect Web: www.RehiveTech.com
RehiveTech
Brno, Czech Republic
next prev parent reply other threads:[~2016-03-21 12:21 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-19 9:26 [dpdk-dev] [PATCH v2] arm: detect NEON by RTE_MACHINE_CPUFLAG_NEON flag only Jan Viktorin
2016-03-19 11:05 ` Jan Viktorin
2016-03-19 19:58 ` [dpdk-dev] [PATCH v3 0/4] " Jan Viktorin
2016-03-24 16:47 ` Thomas Monjalon
2016-03-19 19:58 ` [dpdk-dev] [PATCH v3 1/4] arm: remove CONFIG_RTE_ARCH_ARM_NEON Jan Viktorin
2016-03-19 19:58 ` [dpdk-dev] [PATCH v3 2/4] arm: detect NEON cpu feature by checking __ARM_NEON Jan Viktorin
2016-03-20 17:27 ` Jerin Jacob
2016-03-19 19:58 ` [dpdk-dev] [PATCH v3 3/4] arm: detect NEON by checking RTE_MACHINE_CPUFLAG_NEON Jan Viktorin
2016-03-19 19:58 ` [dpdk-dev] [PATCH v3 4/4] eal/arm: introduce CONFIG_RTE_ARCH_ARM_NEON_MEMCPY Jan Viktorin
2016-03-19 20:14 ` Thomas Monjalon
2016-03-20 9:41 ` Jan Viktorin
2016-03-20 9:46 ` Jan Viktorin
2016-03-20 10:33 ` Thomas Monjalon
2016-03-20 10:29 ` Thomas Monjalon
2016-03-20 17:38 ` Jerin Jacob
2016-03-21 5:42 ` Jianbo Liu
2016-03-21 12:21 ` Jan Viktorin [this message]
2016-03-21 13:24 ` Thomas Monjalon
2016-03-21 14:01 ` Jan Viktorin
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