puffs - don't lock dvp on nresolve

 * locking dvp on nresolve causes a deadlock with the puffsop thread
   when the dvp is the root vnode.

 * If a lookup/nresolve occurs at the same time as a flush via the
   puffsop, then puffsop will not be able to acquire a lock on the root
   vnode as the lookup routine already holds it. Similarly the lookup
   routine never gets woken up waiting for the message to arrive, since
   puffsop is stuck and can't reply.
Merge branch 'master' of git://git.dragonflybsd.org/dragonfly
tcp: Add XMITNOW which bypasses the Nagle algorithm temporarily

This flag acts differently from ACKNOW that no pure ACK will be sent.
It is currently used by the (extended) limited transmit and the SACK
based fast recovery.

This flag is intended to fix the following bug in the SACK based fast
recovery:
The NextSeg() requires that if the unACKed segments could not pass
IsLost(), previously unsent segment should be selected.  In the
application limited period, the size of the previously unsent segment
could be less than the MSS, thus it could not be sent immediately
according to the Nagle algorithm.  In our SACK based fast recovery
implementation, if the tcp_output() sends no segments, the current
recovery transmit process will stop immediately.  This could stop ACK
clock and cause timeout retransmit, which could be avoided, if the
Nagle algorithm is bypassed temporarily for the small unsent segment
selected by NextSeg().

When this flag is used with (extended) limited transmit, certain amount
of spurious early retranmits could be avoided.
bge: Limit BCM5701 B5 to 32-bit mode

This is a workaround for a bug which causes data corruption in
combination with certain bridges.

Obtained-from: FreeBSD 185812
bge: Add missing bit of commit f47afe1
bge: Add busdma constraints for old chips

- Most pre BCM5755 controllers have a DMA bug when buffer address
  crosses a multiple of the 4GB boundary
- For BCM5714/BCM5715 controllers, limit the DMA address to be within
  40bit address space.

Obtained-from: FreeBSD 199670
bge: In bge_stop, don't isolate PHY; it is unnecessary
bge: Revert small part of f47afe1, which setup PHY bugs
bge: Enable hardware fixes for BCM5704 B0 as recommended by datasheet.

Obtained-from: FreeBSD 204975
bge: For BCM5703, limit DMA read watermark

For BCM5703 in PCI-X mode, DMA read watermark should be less than
or equal to maximum read byte count configuration. Enforce this
limitation in DMA read watermark configuration.

Obtained-from: FreeBSD 204978
bge: Proper configure PCI-X for BCM5703/5704 devices

Set maximum read byte count to 2048.  Also disable relaxed ordering
as recommended by data sheet for PCI-X devices.  For PCI-X BCM5704,
set maximum outstanding split transactions to 0 as indicated by
datasheet.

Obtained-from: FreeBSD 204978
Merge branch 'master' of git://git.dragonflybsd.org/dragonfly
top - Display threads when asked to
Merge branch 'master' into gsocdrm_jfree
bge: x86_64 does not have alignment constraint either
bge: Reduce status block device update size

This reduced the amount of data that device needs to DMAed into
host mmeory update status updating.

Obtained-from: FreeBSD 199679

Changes made to the above FreeBSD commit:
- We don't reduce the amount of host memory allocated for status block
- Properly comment why BCM5700 AX/BX need to have full status block
  update setting according to the Broadcom datasheet
bge: Improve TX performance on certain low end chips

These chips, e.g. BCM5761, only allow one outstanding DMA read operation,
so on TX path, mbuf chain should be packed to reduce number of DMA reads
from chip to improve performance.

hw.bgeX.force_defrag is added for PCI-E chips to enable this mbuf chain
packing.  It is not enabled by default.

Obtained-from: FreeBSD 200088
bge: Don't touch jumbo frame registers on chips which do not support them

Obtained-from: FreeBSD 200228

Unlike above FreeBSD commit, we don't change mini ring handling
bge: For dual mode PHY controllers, make sure to enable GMII

Obtained-from: OpenBSD via FreeBSD 202293
bge: Zero out the status block during initialization

Obtained-from: FreeBSD 209741