kernel now passes the name of default console to init process so init
knows which file to open as stdio. before /dev/tty was referencing the
system wide current terminal which was inherited from cmdline. This
doesn't work anymore as we have pseudo terminals implemented that can
chage the current terminal during runtime :D
This makes scheduler preemption much cleaner as bsb does not have to
send smp messages to notify other processes about timer interrupt.
Also PIT percision is now "full" 0.8 us instead of 1 ms that I was using
before.
Change Semaphore -> ThreadBlocker
This was not a semaphore, I just named it one because I didn't know
what semaphore was. I have meant to change this sooner, but it was in
no way urgent :D
Implement SMP events. Processors can now be sent SMP events through
IPIs. SMP events can be sent either to a single processor or broadcasted
to every processor.
PageTable::{map_page,map_range,unmap_page,unmap_range}() now send SMP
event to invalidate TLB caches for the changed pages.
Scheduler no longer uses a global run queue. Each processor has its own
scheduler that keeps track of the load on the processor. Once every
second schedulers do load balancing. Schedulers have no access to other
processors' schedulers, they just see approximate loads. If scheduler
decides that it has too much load, it will send a thread to another
processor through a SMP event.
Schedulers are currently run using the timer interrupt on BSB. This
should be not the case, and each processor should use its LAPIC timer
for interrupts. There is no reason to broadcast SMP event to all
processors when BSB gets timer interrupt.
Old scheduler only achieved 20% idle load on qemu. That was probably a
very inefficient implementation. This new scheduler seems to average
around 1% idle load. This is much closer to what I would expect. On my
own laptop idle load seems to be only around 0.5% on each processor.
/dev/keyboard and /dev/mouse can be read for events from any attached
keyboard or mouse respectively. This makes device hot-plugging support
pretty much automatic for TTY, GUI, and whatever takes input.
This is kinda hacky, as I had disable the PS/2 initialization so that
usb keyboard gets /dev/keyboard0. I should add device hot plugging
support for TTY and GUI...
These can allocate memory that can be shared between processes using
a global key. There is currenly no safety checks meaning anyone can
map any shared memory object just by trying to map every possible key.
Only segment 0 is supported, but devices can now be accessed through
mmio.
Adding more segments would require adding argument to every PCI API so
it is left for later.
This allows us to allocate processor stacks, and other per processor
structures dynamically in runtime. Giving processor stack to
ap_trampoline feels super hacky, but it works for now.
Keycodes are easier to handle as you need only one keyboard layout
for keycodes. Otherwise you would need to implement keyboard layout
for every keyboard driver in every language.
Use this new FramebufferTerminalDriver for terminal instead of the
old VesaTerminalDriver. Only drawback with this is that framebuffer
device can only be intialized after DevFS is initialized.
Bananymous