These instances were detected by searching for files that include
Array.h, but don't match the regex:
\\b(Array(?!\.h>)|iota_array|integer_sequence_generate_array)\\b
These are the three symbols defined by Array.h.
In theory, one might use LibCPP to detect things like this
automatically, but let's do this one step after another.
If a page fault occurs while interrupts are disabled, we were wrongly
enabling interrupts right away in the page fault handler.
Instead, we should only do this if interrupts were enabled when the
page fault occurred.
The hand-written assembly does not compile under Clang due to register
size mismatches. Using a loop is slower (~6 instructions on O2 as
opposed to 2 with hand-written assembly), but using the pause
instruction makes this more efficient even under TCG.
For pause we use isb sy which will put the processor to sleep while the
pipeline is being flushed. This instruction is also used by Rust in spin
loops and found to be more efficient, as well as being a rough
equivalent to the x86 pause instruction which we also use here.
For wait_check we use yield, which is a hinted nop that is faster to
execute, and I leave a FIXME for processing SMP messages once we support
SMP.
These two changes probably make spin loops work on aarch64 :^)
This commit changes the init.cpp file to start and initialize the
Scheduler, and actually runs init_stage2. To show that it actually
works, another thread is spawned and executed simultaneously, by context
switching between the two!
This requires two new functions, context_first_init and
restore_context_and_eret. With this code in place, we are now running
the first idle thread! :^)
This changes the stack pointer to the initial_thread stack pointer, and
pushes two pointers onto the stack that point to the initial_thread. The
function then jumps to the ip of the initial_thread, which will be
thread_context_first_enter, and hangs there because that function is not
yet implemented.
This does not handle everything correctly yet, such as setting the
correct state for running userspace applications, however this should be
enough to get kernel scheduling to work.
These are architecture-specific anyway, so they belong in the Arch
directory. This commit also adds ThreadRegisters::set_initial_state to
factor out the logic in Thread.cpp.
I can't think of a reason why copying the Processor class makes sense,
so lets make sure it's not possible to do it by accident by declaring
the copy constructor as deleted.
This removes the x86 specific hlt instruction from the scheduler, and
allows us to run the scheduler code for aarch64 by implementing
Processor::wait_for_interrupt for aarch64.
This file does not contain any architecture specific implementations,
so we can move it to the Kernel base directory. Also update the relevant
include paths.
We are actually storing tpidr_el0, as can be seen in vector_table.S, but
the RegisterState.h incorrectly had tpidr_el1. This will probably save
some annoying debugging later on.
`SysFSComponentRegistry`, `ProcFSComponentRegistry` and
`attach_null_device` "just work" already; let's include them to match
x86_64 as closely as possible.
We used size_t, which is a type that is guarenteed to be large
enough to hold an array index, but uintptr_t is designed to be used
to hold pointer values, which is the case of stack guards.
