From: Stephen Hemminger <stephen@networkplumber.org>
To: David Harton <dharton@cisco.com>
Cc: dev@dpdk.org, wenzhuo.lu@intel.com, konstantin.ananyev@intel.com
Subject: Re: [dpdk-dev] [PATCH] net/ixgbevf: update VF_STAT macros to handle rollover
Date: Sun, 26 Jan 2020 09:13:01 -0800 [thread overview]
Message-ID: <20200126091301.1b739325@hermes.lan> (raw)
In-Reply-To: <20191211023836.16272-1-dharton@cisco.com>
On Tue, 10 Dec 2019 21:38:36 -0500
David Harton <dharton@cisco.com> wrote:
> Added rollover logic to UPDATE_VF_STAT and UPDATE_VF_STAT_36BIT macros.
>
> Signed-off-by: David Harton <dharton@cisco.com>
> ---
> drivers/net/ixgbe/ixgbe_ethdev.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
> index 49285ce53..bc73ad195 100644
> --- a/drivers/net/ixgbe/ixgbe_ethdev.c
> +++ b/drivers/net/ixgbe/ixgbe_ethdev.c
> @@ -385,7 +385,11 @@ static void ixgbe_l2_tunnel_conf(struct rte_eth_dev *dev);
> #define UPDATE_VF_STAT(reg, last, cur) \
> { \
> uint32_t latest = IXGBE_READ_REG(hw, reg); \
> - cur += (latest - last) & UINT_MAX; \
> + if (latest >= last) \
> + cur += (latest - last); \
> + else \
> + cur += ((latest + ((uint64_t)1 << 32)) - last); \
> + cur &= UINT_MAX; \
> last = latest; \
> }
>
> @@ -394,7 +398,11 @@ static void ixgbe_l2_tunnel_conf(struct rte_eth_dev *dev);
> u64 new_lsb = IXGBE_READ_REG(hw, lsb); \
> u64 new_msb = IXGBE_READ_REG(hw, msb); \
> u64 latest = ((new_msb << 32) | new_lsb); \
> - cur += (0x1000000000LL + latest - last) & 0xFFFFFFFFFLL; \
> + if (latest >= last) \
> + cur += (latest - last); \
> + else \
> + cur += ((latest + ((u64)1 << 36)) - last); \
> + cur &= 0xFFFFFFFFFLL; \
> last = latest; \
> }
The overall approach looks fine.
The code is now long enough the macro should turn into an inline.
Also lots of (extra) parenthesis
next prev parent reply other threads:[~2020-01-26 17:13 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-11 2:38 David Harton
2020-01-26 9:42 ` Ye Xiaolong
2020-01-26 17:13 ` Stephen Hemminger [this message]
2020-01-26 17:32 ` [dpdk-dev] [PATCH v2] " David Harton
2020-01-29 7:53 ` Ye Xiaolong
2020-01-29 11:22 ` Ferruh Yigit
2020-01-29 17:57 ` David Harton (dharton)
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