From 029ee6b14356b94120bedb852dcdaefc0a282cf1 Mon Sep 17 00:00:00 2001 From: Yufeng Mo Date: Fri, 20 Aug 2021 15:35:17 +0800 Subject: ethtool: add two coalesce attributes for CQE mode Currently, there are 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 to make it more generic, add two new 'ETHTOOL_A_COALESCE_USE_CQE_TX' and 'ETHTOOL_A_COALESCE_USE_CQE_RX' coalesce attributes, then these parameters can be accessed by ethtool netlink coalesce uAPI. Also add an new structure kernel_ethtool_coalesce, then the new parameter can be added into this struct. Signed-off-by: Yufeng Mo Signed-off-by: Huazhong Tan Signed-off-by: Jakub Kicinski --- Documentation/networking/ethtool-netlink.rst | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'Documentation') diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst index c690bb37430d..d9b55b7a1a4d 100644 --- a/Documentation/networking/ethtool-netlink.rst +++ b/Documentation/networking/ethtool-netlink.rst @@ -947,12 +947,25 @@ 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 timer reset mode, Tx + ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool timer reset mode, Rx =========================================== ====== ======================= Attributes are only included in reply if their value is not zero or the corresponding bit in ``ethtool_ops::supported_coalesce_params`` is set (i.e. they are declared as supported by driver). +Timer reset mode (``ETHTOOL_A_COALESCE_USE_CQE_TX`` and +``ETHTOOL_A_COALESCE_USE_CQE_RX``) controls the interaction between packet +arrival and the various time based delay parameters. By default timers are +expected to limit the max delay between any packet arrival/departure and a +corresponding interrupt. In this mode timer should be started by packet +arrival (sometimes delivery of previous interrupt) and reset when interrupt +is delivered. +Setting the appropriate attribute to 1 will enable ``CQE`` mode, where +each packet event resets the timer. In this mode timer is used to force +the interrupt if queue goes idle, while busy queues depend on the packet +limit to trigger interrupts. COALESCE_SET ============ @@ -985,6 +998,8 @@ 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 timer reset mode, Tx + ``ETHTOOL_A_COALESCE_USE_CQE_RX`` bool timer reset mode, Rx =========================================== ====== ======================= Request is rejected if it attributes declared as unsupported by driver (i.e. -- cgit v1.2.3