Fix SGX implementation

Author: orlp

std/src/sys/pal/sgx/abi/mod.rs

@@ -3,6 +3,7 @@
 use core::arch::global_asm;
 use core::sync::atomic::{Atomic, AtomicUsize, Ordering};
 
+use crate::alloc::System;
 use crate::io::Write;
 
 // runtime features
@@ -63,7 +64,9 @@ unsafe extern "C" fn tcs_init(secondary: bool) {
 #[unsafe(no_mangle)]
 extern "C" fn entry(p1: u64, p2: u64, p3: u64, secondary: bool, p4: u64, p5: u64) -> EntryReturn {
     // FIXME: how to support TLS in library mode?
-    let tls = Box::new(tls::Tls::new());
+    // We use the System allocator here such that the global allocator may use
+    // thread-locals.
+    let tls = Box::new_in(tls::Tls::new(), System);
     let tls_guard = unsafe { tls.activate() };
 
     if secondary {

std/src/sys/pal/sgx/abi/tls/mod.rs

@@ -89,13 +89,6 @@ impl Tls {
         ActiveTls { tls: self }
     }
 
-    #[allow(unused)]
-    pub unsafe fn activate_persistent(self: Box<Self>) {
-        // FIXME: Needs safety information. See entry.S for `set_tls_ptr` definition.
-        let ptr = Box::into_raw(self).cast_const().cast::<u8>();
-        unsafe { set_tls_ptr(ptr) };
-    }
-
     unsafe fn current<'a>() -> &'a Tls {
         // FIXME: Needs safety information. See entry.S for `set_tls_ptr` definition.
         unsafe { &*(get_tls_ptr() as *const Tls) }

std/src/sys/thread/sgx.rs

@@ -2,6 +2,7 @@
 
 use crate::io;
 use crate::sys::pal::abi::{thread, usercalls};
+use crate::thread::ThreadInit;
 use crate::time::Duration;
 
 pub struct Thread(task_queue::JoinHandle);
@@ -13,6 +14,7 @@ pub use self::task_queue::JoinNotifier;
 mod task_queue {
     use super::wait_notify;
     use crate::sync::{Mutex, MutexGuard};
+    use crate::thread::ThreadInit;
 
     pub type JoinHandle = wait_notify::Waiter;
 
@@ -25,19 +27,20 @@ mod task_queue {
     }
 
     pub(super) struct Task {
-        p: Box<dyn FnOnce() + Send>,
+        init: Box<ThreadInit>,
         done: JoinNotifier,
     }
 
     impl Task {
-        pub(super) fn new(p: Box<dyn FnOnce() + Send>) -> (Task, JoinHandle) {
+        pub(super) fn new(init: Box<ThreadInit>) -> (Task, JoinHandle) {
             let (done, recv) = wait_notify::new();
             let done = JoinNotifier(Some(done));
-            (Task { p, done }, recv)
+            (Task { init, done }, recv)
         }
 
         pub(super) fn run(self) -> JoinNotifier {
-            (self.p)();
+            let rust_start = self.init.init();
+            rust_start();
             self.done
         }
     }
@@ -93,14 +96,10 @@ pub mod wait_notify {
 
 impl Thread {
     // unsafe: see thread::Builder::spawn_unchecked for safety requirements
-    pub unsafe fn new(
-        _stack: usize,
-        _name: Option<&str>,
-        p: Box<dyn FnOnce() + Send>,
-    ) -> io::Result<Thread> {
+    pub unsafe fn new(_stack: usize, init: Box<ThreadInit>) -> io::Result<Thread> {
         let mut queue_lock = task_queue::lock();
         unsafe { usercalls::launch_thread()? };
-        let (task, handle) = task_queue::Task::new(p);
+        let (task, handle) = task_queue::Task::new(init);
         queue_lock.push(task);
         Ok(Thread(handle))
     }

std/src/thread/mod.rs

@@ -218,13 +218,13 @@ pub mod local_impl {
 /// the global allocator works.
 pub(crate) struct ThreadInit {
     pub handle: Thread,
-    pub rust_start: Box<dyn FnOnce()>,
+    pub rust_start: Box<dyn FnOnce() + Send>,
 }
 
 impl ThreadInit {
     /// Initialize the 'current thread' mechanism on this thread, returning the
     /// Rust entry point.
-    pub fn init(self: Box<Self>) -> Box<dyn FnOnce()> {
+    pub fn init(self: Box<Self>) -> Box<dyn FnOnce() + Send> {
         // Set the current thread before any (de)allocations on the global allocator occur,
         // so that it may call std::thread::current() in its implementation. This is also
         // why we take Box<Self>, to ensure the Box is not destroyed until after this point.