Re: [PATCH V4 net-next 1/6] ethtool: add support to set/get tx copybreak buf size via ethtool
flat view
From: Eric Dumazet <hidden>
Date: 2021-10-14 13:58:25
Also in:
linux-s390
On 10/14/21 4:39 AM, Guangbin Huang wrote:
From: Hao Chen <redacted> Add support for ethtool to set/get tx copybreak buf size.
What is the unit ? Frankly, having to size the 'buffer' based on number of slots in TX ring buffer is not good. What happens later when/if ethtool -G tx xxxxx' is trying to change number of slots ? The 'tx copybreak' should instead give a number of bytes per TX ring slot. Eg, 128 or 256 bytes. This is very similar to what drivers using net/core/tso.c do. They usually use TSO_HEADER_SIZE for this.
quoted hunk ↗ jump to hunk
Signed-off-by: Hao Chen <redacted> Signed-off-by: Guangbin Huang <redacted> --- include/uapi/linux/ethtool.h | 1 + net/ethtool/common.c | 1 + net/ethtool/ioctl.c | 1 + 3 files changed, 3 insertions(+)diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index a2223b685451..7bc4b8def12c 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h@@ -231,6 +231,7 @@ enum tunable_id { ETHTOOL_RX_COPYBREAK, ETHTOOL_TX_COPYBREAK, ETHTOOL_PFC_PREVENTION_TOUT, /* timeout in msecs */ + ETHTOOL_TX_COPYBREAK_BUF_SIZE, /* * Add your fresh new tunable attribute above and remember to update * tunable_strings[] in net/ethtool/common.cdiff --git a/net/ethtool/common.c b/net/ethtool/common.c index c63e0739dc6a..0c5210015911 100644 --- a/net/ethtool/common.c +++ b/net/ethtool/common.c@@ -89,6 +89,7 @@ tunable_strings[__ETHTOOL_TUNABLE_COUNT][ETH_GSTRING_LEN] = { [ETHTOOL_RX_COPYBREAK] = "rx-copybreak", [ETHTOOL_TX_COPYBREAK] = "tx-copybreak", [ETHTOOL_PFC_PREVENTION_TOUT] = "pfc-prevention-tout", + [ETHTOOL_TX_COPYBREAK_BUF_SIZE] = "tx-copybreak-buf-size", }; const chardiff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index bf6e8c2f9bf7..617ebc4183d9 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c@@ -2383,6 +2383,7 @@ static int ethtool_tunable_valid(const struct ethtool_tunable *tuna) switch (tuna->id) { case ETHTOOL_RX_COPYBREAK: case ETHTOOL_TX_COPYBREAK: + case ETHTOOL_TX_COPYBREAK_BUF_SIZE: if (tuna->len != sizeof(u32) || tuna->type_id != ETHTOOL_TUNABLE_U32) return -EINVAL;