• Stephen Hurd's avatar
    Roll up iflib commits from github. This pulls in most of the work done · d300df01
    Stephen Hurd authored
    by Matt Macy as well as other changes which he has accepted via pull
    request to his github repo at https://github.com/mattmacy/networking/
    This should bring -CURRENT and the github repo into close enough sync to
    allow small feature branches rather than a large chain of interdependant
    patches being developed out of tree.  The reset of the synchronization
    should be able to be completed on github by splitting the remaining
    changes that are not yet ready into short feature branches for later
    review as smaller commits.
    Here is a summary of changes included in this patch:
    1)  More checks when INVARIANTS are enabled for eariler problem
    2)  Group Task Queue cleanups
        - Fix use of duplicate shortdesc for gtaskqueue malloc type.
          Some interfaces such as memguard(9) use the short description to
          identify malloc types, so duplicates should be avoided.
    3)  Allow gtaskqueues to use ithreads in addition to taskqueues
        - In some cases, this can improve performance
    4)  Better logging when taskqgroup_attach*() fails to set interrupt
    5)  Do not start gtaskqueues until they're needed
    6)  Have mp_ring enqueue function enter the ABDICATED rather than BUSY
        state.  This moves the TX to the gtaskq and allows processing to
        continue faster as well as make TX batching more likely.
    7)  Add an ift_txd_errata function to struct if_txrx.  This allows
        drivers to inspect/modify mbufs before transmission.
    8)  Add a new IFLIB_NEED_ZERO_CSUM for drivers to indicate they need
        checksums zeroed for checksum offload to work.  This avoids modifying
        packet data in the TX path when possible.
    9)  Use ithreads for iflib I/O instead of taskqueues
    10) Clean up ioctl and support async ioctl functions
    11) Prefetch two cachlines from each mbuf instead of one up to 128B.  We
        often need to parse packet header info beyond 64B.
    12) Fix potential memory corruption due to fence post error in
        bit_nclear() usage.
    13) Improved hang detection and handling
    14) If the packet is smaller than MTU, disable the TSO flags.
        This avoids extra packet parsing when not needed.
    15) Move TCP header parsing inside the IS_TSO?() test.
        This avoids extra packet parsing when not needed.
    16) Pass chains of mbufs that are not consumed by lro to if_input()
        rather call if_input() for each mbuf.
    17) Re-arrange packet header loads to get as much work as possible done
        before a cache stall.
    18) Lock the context when calling IFDI_ATTACH_PRE()/IFDI_ATTACH_POST()/
    19) Attempt to distribute RX/TX tasks across cores more sensibly,
        especially when RX and TX share an interrupt.  RX will attempt to
        take the first threads on a core, and TX will attempt to take
        successive threads.
    20) Allow iflib_softirq_alloc_generic() to request affinity to the same
        cpus an interrupt has affinity with.  This allows TX queues to
        ensure they are serviced by the socket the device is on.
    21) Add new iflib sysctls to net.iflib:
        - timer_int - interval at which to run per-queue timers in ticks
        - force_busdma
    22) Add new per-device iflib sysctls to dev.X.Y.iflib
        - rx_budget allows tuning the batch size on the RX path
        - watchdog_events Count of watchdog events seen since load
    23) Fix error where netmap_rxq_init() could get called before
    24) e1000: Fixed version of r323008: post-cold sleep instead of DELAY
        when waiting for firmware
        - After interrupts are enabled, convert all waits to sleeps
        - Eliminates e1000 software/firmware synchronization busy waits after
    25) e1000: Remove special case for budget=1 in em_txrx.c
        - Premature optimization which may actually be incorrect with
          multi-segment packets
    26) e1000: Split out TX interrupt rather than share an interrupt for
        RX and TX.
        - Allows better performance by keeping RX and TX paths separate
    27) e1000: Separate igb from em code where suitable
        Much easier to understand separate functions and "if (is_igb)" than
        previous tests like "if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC))"
    Reviewed by:	sbruno
    Approved by:	sbruno (mentor)
    Sponsored by:	Limelight Networks
    Differential Revision:	https://reviews.freebsd.org/D12235