Add infra so etf qdisc supports HW offload of time-based transmission. For hw offload, the time sorted list is still used, so packets are dequeued always in order of txtime. Example: $ tc qdisc replace dev enp2s0 parent root handle 100 mqprio num_tc 3 \ map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@2 hw 0 $ tc qdisc add dev enp2s0 parent 100:1 etf offload delta 100000 \ clockid CLOCK_REALTIME In this example, the Qdisc will use HW offload for the control of the transmission time through the network adapter. The hrtimer used for packets scheduling inside the qdisc will use the clockid CLOCK_REALTIME as reference and packets leave the Qdisc "delta" (100000) nanoseconds before their transmission time. Because this will be using HW offload and since dynamic clocks are not supported by the hrtimer, the system clock and the PHC clock must be synchronized for this mode to behave as expected.
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| @@ -944,6 +944,7 @@ struct tc_etf_qopt { · 943 unmodified lines | ||
| 944 | 944 | __s32 clockid; |
| 945 | 945 | __u32 flags; |
| 946 | 946 | #define TC_ETF_DEADLINE_MODE_ON BIT(0) |
| 947 | +#define TC_ETF_OFFLOAD_ON BIT(1) | |
| 947 | 948 | }; |
| 948 | 949 | |
| 949 | 950 | enum { |