2021-05-26 09:28:53

by Huazhong Tan

[permalink] [raw]
Subject: [RFC net-next 2/4] ethtool: extend coalesce setting uAPI with CQE mode

Currently, there many drivers who support CQE mode configuration,
some configure it as a fixed when initialized, some provide an
interface to change it by ethtool private flags. In order make it
more generic, add 'ETHTOOL_A_COALESCE_USE_CQE_TX' and
'ETHTOOL_A_COALESCE_USE_CQE_RX' attribute and expand struct
kernel_ethtool_coalesce with use_cqe_mode_tx and use_cqe_mode_rx,
then these parameters can be accessed by ethtool netlink coalesce
uAPI.

Signed-off-by: Huazhong Tan <[email protected]>
---
Documentation/networking/ethtool-netlink.rst | 4 ++++
include/linux/ethtool.h | 6 +++++-
include/uapi/linux/ethtool_netlink.h | 2 ++
net/ethtool/coalesce.c | 19 ++++++++++++++++---
net/ethtool/netlink.h | 2 +-
5 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 25131df..975394e 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -937,6 +937,8 @@ Kernel response contents:
``ETHTOOL_A_COALESCE_TX_USECS_HIGH`` u32 delay (us), high Tx
``ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH`` u32 max packets, high Tx
``ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL`` u32 rate sampling interval
+ ``ETHTOOL_A_COALESCE_USE_CQE_TX`` bool Tx CQE mode
+ ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool Rx CQE mode
=========================================== ====== =======================

Attributes are only included in reply if their value is not zero or the
@@ -975,6 +977,8 @@ Request contents:
``ETHTOOL_A_COALESCE_TX_USECS_HIGH`` u32 delay (us), high Tx
``ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH`` u32 max packets, high Tx
``ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL`` u32 rate sampling interval
+ ``ETHTOOL_A_COALESCE_USE_CQE_TX`` bool Tx CQE mode
+ ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool Rx CQE mode
=========================================== ====== =======================

Request is rejected if it attributes declared as unsupported by driver (i.e.
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 1030540..9d0a386 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -179,6 +179,8 @@ __ethtool_get_link_ksettings(struct net_device *dev,

struct kernel_ethtool_coalesce {
struct ethtool_coalesce base;
+ __u32 use_cqe_mode_tx;
+ __u32 use_cqe_mode_rx;
};

/**
@@ -220,7 +222,9 @@ bool ethtool_convert_link_mode_to_legacy_u32(u32 *legacy_u32,
#define ETHTOOL_COALESCE_TX_USECS_HIGH BIT(19)
#define ETHTOOL_COALESCE_TX_MAX_FRAMES_HIGH BIT(20)
#define ETHTOOL_COALESCE_RATE_SAMPLE_INTERVAL BIT(21)
-#define ETHTOOL_COALESCE_ALL_PARAMS GENMASK(21, 0)
+#define ETHTOOL_COALESCE_USE_CQE_RX BIT(22)
+#define ETHTOOL_COALESCE_USE_CQE_TX BIT(23)
+#define ETHTOOL_COALESCE_ALL_PARAMS GENMASK(23, 0)

#define ETHTOOL_COALESCE_USECS \
(ETHTOOL_COALESCE_RX_USECS | ETHTOOL_COALESCE_TX_USECS)
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 825cfda..1ad32a4 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -375,6 +375,8 @@ enum {
ETHTOOL_A_COALESCE_TX_USECS_HIGH, /* u32 */
ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH, /* u32 */
ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL, /* u32 */
+ ETHTOOL_A_COALESCE_USE_CQE_MODE_TX, /* u8 */
+ ETHTOOL_A_COALESCE_USE_CQE_MODE_RX, /* u8 */

/* add new constants above here */
__ETHTOOL_A_COALESCE_CNT,
diff --git a/net/ethtool/coalesce.c b/net/ethtool/coalesce.c
index 70e6331..2000c56 100644
--- a/net/ethtool/coalesce.c
+++ b/net/ethtool/coalesce.c
@@ -101,7 +101,9 @@ static int coalesce_reply_size(const struct ethnl_req_info *req_base,
nla_total_size(sizeof(u32)) + /* _RX_MAX_FRAMES_HIGH */
nla_total_size(sizeof(u32)) + /* _TX_USECS_HIGH */
nla_total_size(sizeof(u32)) + /* _TX_MAX_FRAMES_HIGH */
- nla_total_size(sizeof(u32)); /* _RATE_SAMPLE_INTERVAL */
+ nla_total_size(sizeof(u32)) + /* _RATE_SAMPLE_INTERVAL */
+ nla_total_size(sizeof(u8)) + /* _USE_CQE_MODE_TX */
+ nla_total_size(sizeof(u8)); /* _USE_CQE_MODE_RX */
}

static bool coalesce_put_u32(struct sk_buff *skb, u16 attr_type, u32 val,
@@ -125,7 +127,8 @@ static int coalesce_fill_reply(struct sk_buff *skb,
const struct ethnl_reply_data *reply_base)
{
const struct coalesce_reply_data *data = COALESCE_REPDATA(reply_base);
- const struct ethtool_coalesce *cbase = &data->coalesce.base;
+ const struct kernel_ethtool_coalesce *coalesce = &data->coalesce;
+ const struct ethtool_coalesce *cbase = &coalesce->base;
u32 supported = data->supported_params;

if (coalesce_put_u32(skb, ETHTOOL_A_COALESCE_RX_USECS,
@@ -171,7 +174,11 @@ static int coalesce_fill_reply(struct sk_buff *skb,
coalesce_put_u32(skb, ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH,
cbase->tx_max_coalesced_frames_high, supported) ||
coalesce_put_u32(skb, ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL,
- cbase->rate_sample_interval, supported))
+ cbase->rate_sample_interval, supported) ||
+ coalesce_put_bool(skb, ETHTOOL_A_COALESCE_USE_CQE_MODE_TX,
+ coalesce->use_cqe_mode_tx, supported) ||
+ coalesce_put_bool(skb, ETHTOOL_A_COALESCE_USE_CQE_MODE_RX,
+ coalesce->use_cqe_mode_rx, supported))
return -EMSGSIZE;

return 0;
@@ -216,6 +223,8 @@ const struct nla_policy ethnl_coalesce_set_policy[] = {
[ETHTOOL_A_COALESCE_TX_USECS_HIGH] = { .type = NLA_U32 },
[ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH] = { .type = NLA_U32 },
[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL] = { .type = NLA_U32 },
+ [ETHTOOL_A_COALESCE_USE_CQE_MODE_TX] = { .type = NLA_U8 },
+ [ETHTOOL_A_COALESCE_USE_CQE_MODE_RX] = { .type = NLA_U8 },
};

int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info)
@@ -305,6 +314,10 @@ int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info)
tb[ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH], &mod);
ethnl_update_u32(&cbase->rate_sample_interval,
tb[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL], &mod);
+ ethnl_update_bool32(&coalesce.use_cqe_mode_tx,
+ tb[ETHTOOL_A_COALESCE_USE_CQE_MODE_TX], &mod);
+ ethnl_update_bool32(&coalesce.use_cqe_mode_rx,
+ tb[ETHTOOL_A_COALESCE_USE_CQE_MODE_RX], &mod);
ret = 0;
if (!mod)
goto out_ops;
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 8abcbc1..868e33e 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -369,7 +369,7 @@ extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_TX + 1];
extern const struct nla_policy ethnl_channels_get_policy[ETHTOOL_A_CHANNELS_HEADER + 1];
extern const struct nla_policy ethnl_channels_set_policy[ETHTOOL_A_CHANNELS_COMBINED_COUNT + 1];
extern const struct nla_policy ethnl_coalesce_get_policy[ETHTOOL_A_COALESCE_HEADER + 1];
-extern const struct nla_policy ethnl_coalesce_set_policy[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL + 1];
+extern const struct nla_policy ethnl_coalesce_set_policy[ETHTOOL_A_COALESCE_MAX + 1];
extern const struct nla_policy ethnl_pause_get_policy[ETHTOOL_A_PAUSE_HEADER + 1];
extern const struct nla_policy ethnl_pause_set_policy[ETHTOOL_A_PAUSE_TX + 1];
extern const struct nla_policy ethnl_eee_get_policy[ETHTOOL_A_EEE_HEADER + 1];
--
2.7.4


2021-05-27 01:27:26

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [RFC net-next 2/4] ethtool: extend coalesce setting uAPI with CQE mode

On Wed, 26 May 2021 17:27:40 +0800 Huazhong Tan wrote:
> Currently, there many drivers who support CQE mode configuration,
> some configure it as a fixed when initialized, some provide an
> interface to change it by ethtool private flags. In order make it
> more generic, add 'ETHTOOL_A_COALESCE_USE_CQE_TX' and
> 'ETHTOOL_A_COALESCE_USE_CQE_RX' attribute and expand struct
> kernel_ethtool_coalesce with use_cqe_mode_tx and use_cqe_mode_rx,
> then these parameters can be accessed by ethtool netlink coalesce
> uAPI.
>
> Signed-off-by: Huazhong Tan <[email protected]>

> diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
> index 25131df..975394e 100644
> --- a/Documentation/networking/ethtool-netlink.rst
> +++ b/Documentation/networking/ethtool-netlink.rst
> @@ -937,6 +937,8 @@ Kernel response contents:
> ``ETHTOOL_A_COALESCE_TX_USECS_HIGH`` u32 delay (us), high Tx
> ``ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH`` u32 max packets, high Tx
> ``ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL`` u32 rate sampling interval
> + ``ETHTOOL_A_COALESCE_USE_CQE_TX`` bool Tx CQE mode
> + ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool Rx CQE mode
> =========================================== ====== =======================
>
> Attributes are only included in reply if their value is not zero or the
> @@ -975,6 +977,8 @@ Request contents:
> ``ETHTOOL_A_COALESCE_TX_USECS_HIGH`` u32 delay (us), high Tx
> ``ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH`` u32 max packets, high Tx
> ``ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL`` u32 rate sampling interval
> + ``ETHTOOL_A_COALESCE_USE_CQE_TX`` bool Tx CQE mode
> + ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool Rx CQE mode
> =========================================== ====== =======================
>
> Request is rejected if it attributes declared as unsupported by driver (i.e.

You need to thoroughly document the semantics. Can you point us to
which drivers/devices implement similar modes of operation (if they
exist we need to make sure semantics match)?

> diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
> index 1030540..9d0a386 100644
> --- a/include/linux/ethtool.h
> +++ b/include/linux/ethtool.h
> @@ -179,6 +179,8 @@ __ethtool_get_link_ksettings(struct net_device *dev,
>
> struct kernel_ethtool_coalesce {
> struct ethtool_coalesce base;
> + __u32 use_cqe_mode_tx;
> + __u32 use_cqe_mode_rx;

No __ in front, this is not a user space structure.
Why not bool or a bitfield?

> };
>
> /**

> @@ -216,6 +223,8 @@ const struct nla_policy ethnl_coalesce_set_policy[] = {
> [ETHTOOL_A_COALESCE_TX_USECS_HIGH] = { .type = NLA_U32 },
> [ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH] = { .type = NLA_U32 },
> [ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL] = { .type = NLA_U32 },
> + [ETHTOOL_A_COALESCE_USE_CQE_MODE_TX] = { .type = NLA_U8 },
> + [ETHTOOL_A_COALESCE_USE_CQE_MODE_RX] = { .type = NLA_U8 },

This needs a policy to make sure values are <= 1.

2021-05-27 02:27:32

by Huazhong Tan

[permalink] [raw]
Subject: Re: [RFC net-next 2/4] ethtool: extend coalesce setting uAPI with CQE mode


On 2021/5/27 8:00, Jakub Kicinski wrote:
> On Wed, 26 May 2021 17:27:40 +0800 Huazhong Tan wrote:
>> Currently, there many drivers who support CQE mode configuration,
>> some configure it as a fixed when initialized, some provide an
>> interface to change it by ethtool private flags. In order make it
>> more generic, add 'ETHTOOL_A_COALESCE_USE_CQE_TX' and
>> 'ETHTOOL_A_COALESCE_USE_CQE_RX' attribute and expand struct
>> kernel_ethtool_coalesce with use_cqe_mode_tx and use_cqe_mode_rx,
>> then these parameters can be accessed by ethtool netlink coalesce
>> uAPI.
>>
>> Signed-off-by: Huazhong Tan <[email protected]>
>> diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
>> index 25131df..975394e 100644
>> --- a/Documentation/networking/ethtool-netlink.rst
>> +++ b/Documentation/networking/ethtool-netlink.rst
>> @@ -937,6 +937,8 @@ Kernel response contents:
>> ``ETHTOOL_A_COALESCE_TX_USECS_HIGH`` u32 delay (us), high Tx
>> ``ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH`` u32 max packets, high Tx
>> ``ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL`` u32 rate sampling interval
>> + ``ETHTOOL_A_COALESCE_USE_CQE_TX`` bool Tx CQE mode
>> + ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool Rx CQE mode
>> =========================================== ====== =======================
>>
>> Attributes are only included in reply if their value is not zero or the
>> @@ -975,6 +977,8 @@ Request contents:
>> ``ETHTOOL_A_COALESCE_TX_USECS_HIGH`` u32 delay (us), high Tx
>> ``ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH`` u32 max packets, high Tx
>> ``ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL`` u32 rate sampling interval
>> + ``ETHTOOL_A_COALESCE_USE_CQE_TX`` bool Tx CQE mode
>> + ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool Rx CQE mode
>> =========================================== ====== =======================
>>
>> Request is rejected if it attributes declared as unsupported by driver (i.e.
> You need to thoroughly document the semantics. Can you point us to
> which drivers/devices implement similar modes of operation (if they
> exist we need to make sure semantics match)?


Ok, will complement the semantics.


Currently, only mlx5 provides a interface to update
this mode through ethtool priv-flag. other drivers like
broadcom and ice just use a fixed EQE and do not have
update interface.



>> diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
>> index 1030540..9d0a386 100644
>> --- a/include/linux/ethtool.h
>> +++ b/include/linux/ethtool.h
>> @@ -179,6 +179,8 @@ __ethtool_get_link_ksettings(struct net_device *dev,
>>
>> struct kernel_ethtool_coalesce {
>> struct ethtool_coalesce base;
>> + __u32 use_cqe_mode_tx;
>> + __u32 use_cqe_mode_rx;
> No __ in front, this is not a user space structure.
> Why not bool or a bitfield?


bool is enough, __u32 is used here to be consistent with

fields in struct ethtool_coalesce.

This seems unnecessary?


>> };
>>
>> /**
>> @@ -216,6 +223,8 @@ const struct nla_policy ethnl_coalesce_set_policy[] = {
>> [ETHTOOL_A_COALESCE_TX_USECS_HIGH] = { .type = NLA_U32 },
>> [ETHTOOL_A_COALESCE_TX_MAX_FRAMES_HIGH] = { .type = NLA_U32 },
>> [ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL] = { .type = NLA_U32 },
>> + [ETHTOOL_A_COALESCE_USE_CQE_MODE_TX] = { .type = NLA_U8 },
>> + [ETHTOOL_A_COALESCE_USE_CQE_MODE_RX] = { .type = NLA_U8 },
> This needs a policy to make sure values are <= 1.
>
> .

2021-05-27 19:04:50

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [RFC net-next 2/4] ethtool: extend coalesce setting uAPI with CQE mode

On Thu, 27 May 2021 10:00:44 +0800 Huazhong Tan wrote:
> >> @@ -179,6 +179,8 @@ __ethtool_get_link_ksettings(struct net_device *dev,
> >>
> >> struct kernel_ethtool_coalesce {
> >> struct ethtool_coalesce base;
> >> + __u32 use_cqe_mode_tx;
> >> + __u32 use_cqe_mode_rx;
> > No __ in front, this is not a user space structure.
> > Why not bool or a bitfield?
>
> bool is enough, __u32 is used here to be consistent with
>
> fields in struct ethtool_coalesce.
>
> This seems unnecessary?

Yup, I think the IOCTL made everything a __u32 for uniformity
of the uAPI and to avoid holes and paddings. This is an internal
kernel structure so natural types like bool are better.