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netinet/tcp_stacks/rack_bbr_common.c
| Context not available. | |||||
| } | } | ||||
| #endif | #endif | ||||
| /* | |||||
| * The function ctf_process_inbound_raw() is used by | |||||
| * transport developers to do the steps needed to | |||||
| * support MBUF Queuing i.e. the flags in | |||||
| * inp->inp_flags2: | |||||
| * | |||||
| * - INP_SUPPORTS_MBUFQ | |||||
| * - INP_MBUF_QUEUE_READY | |||||
| * - INP_DONT_SACK_QUEUE | |||||
| * | |||||
| * These flags help control how LRO will deliver | |||||
| * packets to the transport. You first set in inp_flags2 | |||||
| * the INP_SUPPORTS_MBUFQ to tell the LRO code that you | |||||
| * will gladly take a queue of packets instead of a compressed | |||||
| * single packet. You also set in your t_fb pointer the | |||||
| * tfb_do_queued_segments to point to ctf_process_inbound_raw. | |||||
| * | |||||
| * This then gets you lists of inbound ACK's/Data instead | |||||
| * of a condensed compressed ACK/DATA packet. Why would you | |||||
| * want that? This will get you access to all the arrival | |||||
| * times of at least LRO and possibly at the Hardware (if | |||||
| * the interface card supports that) of the actual ACK/DATA. | |||||
| * In some transport designs this is important since knowing | |||||
| * the actual time we got the packet is useful information. | |||||
| * | |||||
| * Now there are some interesting Caveats that the transport | |||||
| * designer needs to take into account when using this feature. | |||||
| * | |||||
| * 1) It is used with HPTS and pacing, when the pacing timer | |||||
| * for output calls it will first call the input. | |||||
| * 2) When you set INP_MBUF_QUEUE_READY this tells LRO | |||||
| * queue normal packets, I am busy pacing out data and | |||||
| * will process the queued packets before my tfb_tcp_output | |||||
| * call from pacing. If a non-normal packet arrives, (e.g. sack) | |||||
| * you will be awoken immediately. | |||||
| * 3) Finally you can add the INP_DONT_SACK_QUEUE to not even | |||||
| * be awoken if a SACK has arrived. You would do this when | |||||
| * you were not only running a pacing for output timer | |||||
| * but a Rack timer as well i.e. you know you are in recovery | |||||
| * and are in the process (via the timers) of dealing with | |||||
| * the loss. | |||||
| * | |||||
| * Now a critical thing you must be aware of here is that the | |||||
| * use of the flags has a far greater scope then just your | |||||
| * typical LRO. Why? Well thats because in the normal compressed | |||||
| * LRO case at the end of a driver interupt all packets are going | |||||
| * to get presented to the transport no matter if there is one | |||||
| * or 100. With the MBUF_QUEUE model, this is not true. You will | |||||
| * only be awoken to process the queue of packets when: | |||||
| * a) The flags discussed above allow it. | |||||
| * <or> | |||||
| * b) You exceed a ack or data limit (by default the | |||||
| * ack limit is infinity (64k acks) and the data | |||||
| * limit is 64k of new TCP data) | |||||
| * <or> | |||||
| * c) The push bit has been set by the peer | |||||
| */ | |||||
| int | int | ||||
| ctf_process_inbound_raw(struct tcpcb *tp, struct socket *so, struct mbuf *m, int has_pkt) | ctf_process_inbound_raw(struct tcpcb *tp, struct socket *so, struct mbuf *m, int has_pkt) | ||||
| { | { | ||||
| Context not available. | |||||
| * have been called (if we can). | * have been called (if we can). | ||||
| */ | */ | ||||
| m->m_pkthdr.lro_nsegs = 1; | m->m_pkthdr.lro_nsegs = 1; | ||||
| if (m->m_flags & M_TSTMP_LRO) { | tcp_get_usecs(&tv); | ||||
| tv.tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000; | |||||
| tv.tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000) / 1000; | |||||
| } else { | |||||
| /* Should not be should we kassert instead? */ | |||||
| tcp_get_usecs(&tv); | |||||
| } | |||||
| /* Now what about next packet? */ | /* Now what about next packet? */ | ||||
| if (m_save || has_pkt) | if (m_save || has_pkt) | ||||
| nxt_pkt = 1; | nxt_pkt = 1; | ||||
| Context not available. | |||||