DPDK patches and discussions
 help / color / mirror / Atom feed
From: Ferruh Yigit <ferruh.yigit@intel.com>
To: Junyu Jiang <junyux.jiang@intel.com>, dev@dpdk.org
Cc: Jeff Guo <jia.guo@intel.com>, Beilei Xing <beilei.xing@intel.com>,
	stable@dpdk.org
Subject: Re: [dpdk-dev] [dpdk-stable] [PATCH v2] net/i40e: fix incorrect byte counters
Date: Wed, 16 Sep 2020 13:30:31 +0100
Message-ID: <295e61ad-cbc5-3fbe-c996-c3f9a11b34d6@intel.com> (raw)
In-Reply-To: <20200916015105.39815-1-junyux.jiang@intel.com>

On 9/16/2020 2:51 AM, Junyu Jiang wrote:
> This patch fixed the issue that rx/tx bytes overflowed

"Rx/Tx statistics counters overflowed"?

> on 48 bit limitation by enlarging the limitation.
> 
> Fixes: 4861cde46116 ("i40e: new poll mode driver")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Junyu Jiang <junyux.jiang@intel.com>
> ---
>   drivers/net/i40e/i40e_ethdev.c | 47 ++++++++++++++++++++++++++++++++++
>   drivers/net/i40e/i40e_ethdev.h |  9 +++++++
>   2 files changed, 56 insertions(+)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 563f21d9d..4d4ea9861 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -3073,6 +3073,13 @@ i40e_update_vsi_stats(struct i40e_vsi *vsi)
>   	i40e_stat_update_48(hw, I40E_GLV_BPRCH(idx), I40E_GLV_BPRCL(idx),
>   			    vsi->offset_loaded, &oes->rx_broadcast,
>   			    &nes->rx_broadcast);
> +	/* enlarge the limitation when rx_bytes overflowed */
> +	if (vsi->offset_loaded) {
> +		if (I40E_RXTX_BYTES_LOW(vsi->old_rx_bytes) > nes->rx_bytes)
> +			nes->rx_bytes += (uint64_t)1 << I40E_48_BIT_WIDTH;
> +		nes->rx_bytes += I40E_RXTX_BYTES_HIGH(vsi->old_rx_bytes);
> +	}
> +	vsi->old_rx_bytes = nes->rx_bytes;


Can you please describe this logic? (indeed better to describe it in the 
commit log)

'nes->rx_bytes' is diff in the stats register since last read.
'old_rx_bytes' is the previous stats diff.

Why/how "I40E_RXTX_BYTES_LOW(vsi->old_rx_bytes) > nes->rx_bytes" has a 
meaning? Isn't this very depends on the read frequency?

I guess I am missing something but please help me understand.

Also can you please confirm the initial value of the 
"vsi->offset_loaded" is correct.

<....>

> @@ -282,6 +282,9 @@ struct rte_flow {
>   #define I40E_ETH_OVERHEAD \
>   	(RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN + I40E_VLAN_TAG_SIZE * 2)
>   
> +#define I40E_RXTX_BYTES_HIGH(bytes) ((bytes) & ~I40E_48_BIT_MASK)
> +#define I40E_RXTX_BYTES_LOW(bytes) ((bytes) & I40E_48_BIT_MASK)
> +

HIGH/LOW is a little misleading, for 64Bits it sounds like it is getting 
low 32 bits and high 32 bits, can you please clarify macro masks out 
48/16 bits.


>   struct i40e_adapter;
>   struct rte_pci_driver;
>   
> @@ -399,6 +402,8 @@ struct i40e_vsi {
>   	uint8_t vlan_anti_spoof_on; /* The VLAN anti-spoofing enabled */
>   	uint8_t vlan_filter_on; /* The VLAN filter enabled */
>   	struct i40e_bw_info bw_info; /* VSI bandwidth information */
> +	uint64_t old_rx_bytes;
> +	uint64_t old_tx_bytes;

'prev' seems better naming than 'old', what do you think renaming 
'old_rx_bytes' -> 'prev_rx_bytes' (for all variables)?

  parent reply	other threads:[~2020-09-16 12:30 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-10  1:54 [dpdk-dev] [PATCH] " Junyu Jiang
2020-09-10  2:18 ` [dpdk-dev] [dpdk-stable] " Han, YingyaX
2020-09-10  5:58   ` Guo, Jia
2020-09-10  6:45     ` Jiang, JunyuX
2020-09-16  1:51 ` [dpdk-dev] [PATCH v2] " Junyu Jiang
2020-09-16  2:39   ` [dpdk-dev] [dpdk-stable] " Han, YingyaX
2020-09-16  5:21   ` [dpdk-dev] " Guo, Jia
2020-09-16  5:50     ` Zhang, Qi Z
2020-09-16 12:30   ` Ferruh Yigit [this message]
2020-09-18  3:44     ` [dpdk-dev] [dpdk-stable] " Jiang, JunyuX
2020-09-18  9:23       ` Igor Ryzhov
2020-09-18 13:42         ` Ferruh Yigit
2020-09-21  1:55           ` Jiang, JunyuX
2020-09-18 13:37       ` Ferruh Yigit
2020-09-21  9:59 ` [dpdk-dev] [PATCH v3] " Junyu Jiang
2020-09-21 11:41   ` Ferruh Yigit
2020-09-22  7:37 ` [dpdk-dev] [PATCH v4] " Junyu Jiang
2020-09-22  9:06   ` Ferruh Yigit
2020-09-22  9:19 ` [dpdk-dev] [PATCH v5] " Junyu Jiang
2020-09-22 12:59   ` Zhang, Qi Z

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=295e61ad-cbc5-3fbe-c996-c3f9a11b34d6@intel.com \
    --to=ferruh.yigit@intel.com \
    --cc=beilei.xing@intel.com \
    --cc=dev@dpdk.org \
    --cc=jia.guo@intel.com \
    --cc=junyux.jiang@intel.com \
    --cc=stable@dpdk.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

DPDK patches and discussions

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ https://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git