If the machine has network cards found, but there are no tcp open sockets
(because the user doesn't use the network to boot), then grub_net_tcp_retransmit()
should be a noop. Thus GRUB doesn't need to call grub_get_time_ms(), which
does a call into firmware on powerpc-ieee1275, and probably other targets.
So only call grub_get_time_ms() if there are tcp sockets.
Aside from improving performance, its also useful to stay out of the firmware
as much as possible when debugging via QEMU because its a pain to get back
in to GRUB execution. grub_net_tcp_retransmit() can get called very frequently
via grub_net_poll_cards_idle() when GRUB is waiting for a keypress
(grub_getkey_noblock() calls grub_net_poll_cards_idle()). This can be annoying
when debugging an issue in GRUB on PowerPC in QEMU with GDB when GRUB is waiting
for a keypress because interrupting via GDB nearly always lands in the OpenBIOS
firmware's milliseconds call.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>