Revert "pktgen: clean up ktime_t helpers"

This reverts commit 955eba07863ab6ec096bf606249d39e036bdb5af.

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
Revert "iopoll: Use ktime_get() instead of jiffies for timeout calculations"

This reverts commit 3cc1e88bd19cc6cbc6a6848230cb00f7223d0144.

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
Revert "iopoll: Make readl_poll_timeout() and friends preemption-safe"

This reverts commit 5143f2685e5ab25fa24a6c3285b2c99f978de2b2.

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
Revert "ghost: Kill most debugging by now"

This reverts commit f98fc76fcef491d95032e210bd0b8ad299753bf5.

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
net: loopback: set default mtu to 64K

loopback current mtu of 16436 bytes allows no more than 3 MSS TCP
segments per frame, or 48 Kbytes. Changing mtu to 64K allows TCP
stack to build large frames and significantly reduces stack overhead.

Performance boost on bulk TCP transferts can be up to 30 %, partly
because we now have one ACK message for two 64KB segments, and a lower
probability of hitting /proc/sys/net/ipv4/tcp_reordering default limit.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>