We now delete threads when
1. it is marked as Terminated and is the current thread
2. it tries to start execution in Terminated state
This allows us to never have thread executing in Terminated state
When we want to kill a process, we mark its threads as Terminating
or Terminated. If the thread is in critical section that has to be
finished, it will be in Terminating state until done. Once Scheduler
is trying to execute Terminated thread it will instead delete it.
Once processes last thread is marked Terminated, the processes will
turn it into a cleanup thread, that will allow blocks and memory
cleanup to be done.
I added a syscall for telling the kernel when signal execution has
finished. We should send a random hash or id to the signal trampoline
that we would include in the syscall, so validity of signal exit can
be confirmed.
We now load ELF files to VirtualRanges instead of using kmalloc.
We have only a fixed 1 MiB kmalloc for big allocations and this
allows loading files even when they don't fit in there.
This caused me to rewrite the whole ELF loading process since the
loaded ELF is not in memory mapped by every process.
Virtual ranges allow you to zero out the memory and to copy into
them from arbitary byte buffers.
MMU moved to namespace kernel
Kernel::Memory::Heap moved to just Kernel
MMU::map_{page,range} renamed to identity_map_{page,range}
Add MMU::get_page_flags
This disables interrupts for the current scope and restores them
after the scope. This is used in kmalloc, since scheduler might
call into kmalloc/kfree, but deadlock if some thread is currently
trying to allocate. This allows us to use kmalloc in Scheduler.
We can now use arbitary BAN::function<void(...)> as the Thread.
I also implemented multithreading for i386 since it was not done
on the initial multithreading commit.
This still uses only a single cpu, but we can now have 'parallelization'
This seems to work fine in qemu and bochs, but my own computer did not
like this when I last tried.
I have absolutely no idea how multithreading should actually be
implmemented and I just thought and implemented the most simple one I
could think of. This might not be in any way correct :D
Bananymous