mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-02 07:22:42 +00:00
std: xous: add thread support
Add initial support for threads on Xous. This includes thread creation and joining. Signed-off-by: Sean Cross <sean@xobs.io>
This commit is contained in:
parent
efa470d0ae
commit
d36e516478
@ -27,7 +27,6 @@ pub mod pipe;
|
||||
#[path = "../unsupported/process.rs"]
|
||||
pub mod process;
|
||||
pub mod stdio;
|
||||
#[path = "../unsupported/thread.rs"]
|
||||
pub mod thread;
|
||||
#[path = "../unsupported/thread_local_key.rs"]
|
||||
pub mod thread_local_key;
|
||||
|
144
library/std/src/sys/xous/thread.rs
Normal file
144
library/std/src/sys/xous/thread.rs
Normal file
@ -0,0 +1,144 @@
|
||||
use crate::ffi::CStr;
|
||||
use crate::io;
|
||||
use crate::num::NonZeroUsize;
|
||||
use crate::os::xous::ffi::{
|
||||
blocking_scalar, create_thread, do_yield, join_thread, map_memory, update_memory_flags,
|
||||
MemoryFlags, Syscall, ThreadId,
|
||||
};
|
||||
use crate::os::xous::services::{ticktimer_server, TicktimerScalar};
|
||||
use crate::time::Duration;
|
||||
use core::arch::asm;
|
||||
|
||||
pub struct Thread {
|
||||
tid: ThreadId,
|
||||
}
|
||||
|
||||
pub const DEFAULT_MIN_STACK_SIZE: usize = 131072;
|
||||
const MIN_STACK_SIZE: usize = 4096;
|
||||
pub const GUARD_PAGE_SIZE: usize = 4096;
|
||||
|
||||
impl Thread {
|
||||
// unsafe: see thread::Builder::spawn_unchecked for safety requirements
|
||||
pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> {
|
||||
let p = Box::into_raw(Box::new(p));
|
||||
let mut stack_size = crate::cmp::max(stack, MIN_STACK_SIZE);
|
||||
|
||||
if (stack_size & 4095) != 0 {
|
||||
stack_size = (stack_size + 4095) & !4095;
|
||||
}
|
||||
|
||||
// Allocate the whole thing, then divide it up after the fact. This ensures that
|
||||
// even if there's a context switch during this function, the whole stack plus
|
||||
// guard pages will remain contiguous.
|
||||
let stack_plus_guard_pages: &mut [u8] = unsafe {
|
||||
map_memory(
|
||||
None,
|
||||
None,
|
||||
GUARD_PAGE_SIZE + stack_size + GUARD_PAGE_SIZE,
|
||||
MemoryFlags::R | MemoryFlags::W | MemoryFlags::X,
|
||||
)
|
||||
}
|
||||
.map_err(|code| io::Error::from_raw_os_error(code as i32))?;
|
||||
|
||||
// No access to this page. Note: Write-only pages are illegal, and will
|
||||
// cause an access violation.
|
||||
unsafe {
|
||||
update_memory_flags(&mut stack_plus_guard_pages[0..GUARD_PAGE_SIZE], MemoryFlags::W)
|
||||
.map_err(|code| io::Error::from_raw_os_error(code as i32))?
|
||||
};
|
||||
|
||||
// No access to this page. Note: Write-only pages are illegal, and will
|
||||
// cause an access violation.
|
||||
unsafe {
|
||||
update_memory_flags(
|
||||
&mut stack_plus_guard_pages[(GUARD_PAGE_SIZE + stack_size)..],
|
||||
MemoryFlags::W,
|
||||
)
|
||||
.map_err(|code| io::Error::from_raw_os_error(code as i32))?
|
||||
};
|
||||
|
||||
let guard_page_pre = stack_plus_guard_pages.as_ptr() as usize;
|
||||
let tid = create_thread(
|
||||
thread_start as *mut usize,
|
||||
&mut stack_plus_guard_pages[GUARD_PAGE_SIZE..(stack_size + GUARD_PAGE_SIZE)],
|
||||
p as usize,
|
||||
guard_page_pre,
|
||||
stack_size,
|
||||
0,
|
||||
)
|
||||
.map_err(|code| io::Error::from_raw_os_error(code as i32))?;
|
||||
|
||||
extern "C" fn thread_start(main: *mut usize, guard_page_pre: usize, stack_size: usize) {
|
||||
unsafe {
|
||||
// Finally, let's run some code.
|
||||
Box::from_raw(main as *mut Box<dyn FnOnce()>)();
|
||||
}
|
||||
|
||||
// Destroy TLS, which will free the TLS page and call the destructor for
|
||||
// any thread local storage.
|
||||
unsafe {
|
||||
crate::sys::thread_local_key::destroy_tls();
|
||||
}
|
||||
|
||||
// Deallocate the stack memory, along with the guard pages. Afterwards,
|
||||
// exit the thread by returning to the magic address 0xff80_3000usize,
|
||||
// which tells the kernel to deallocate this thread.
|
||||
let mapped_memory_base = guard_page_pre;
|
||||
let mapped_memory_length = GUARD_PAGE_SIZE + stack_size + GUARD_PAGE_SIZE;
|
||||
unsafe {
|
||||
asm!(
|
||||
"ecall",
|
||||
"ret",
|
||||
in("a0") Syscall::UnmapMemory as usize,
|
||||
in("a1") mapped_memory_base,
|
||||
in("a2") mapped_memory_length,
|
||||
in("ra") 0xff80_3000usize,
|
||||
options(nomem, nostack, noreturn)
|
||||
);
|
||||
}
|
||||
}
|
||||
|
||||
Ok(Thread { tid })
|
||||
}
|
||||
|
||||
pub fn yield_now() {
|
||||
do_yield();
|
||||
}
|
||||
|
||||
pub fn set_name(_name: &CStr) {
|
||||
// nope
|
||||
}
|
||||
|
||||
pub fn sleep(dur: Duration) {
|
||||
// Because the sleep server works on units of `usized milliseconds`, split
|
||||
// the messages up into these chunks. This means we may run into issues
|
||||
// if you try to sleep a thread for more than 49 days on a 32-bit system.
|
||||
let mut millis = dur.as_millis();
|
||||
while millis > 0 {
|
||||
let sleep_duration =
|
||||
if millis > (usize::MAX as _) { usize::MAX } else { millis as usize };
|
||||
blocking_scalar(ticktimer_server(), TicktimerScalar::SleepMs(sleep_duration).into())
|
||||
.expect("failed to send message to ticktimer server");
|
||||
millis -= sleep_duration as u128;
|
||||
}
|
||||
}
|
||||
|
||||
pub fn join(self) {
|
||||
join_thread(self.tid).unwrap();
|
||||
}
|
||||
}
|
||||
|
||||
pub fn available_parallelism() -> io::Result<NonZeroUsize> {
|
||||
// We're unicore right now.
|
||||
Ok(unsafe { NonZeroUsize::new_unchecked(1) })
|
||||
}
|
||||
|
||||
pub mod guard {
|
||||
pub type Guard = !;
|
||||
pub unsafe fn current() -> Option<Guard> {
|
||||
None
|
||||
}
|
||||
pub unsafe fn init() -> Option<Guard> {
|
||||
None
|
||||
}
|
||||
}
|
Loading…
Reference in New Issue
Block a user