Changeset 5c1a531 for libcfa/src/concurrency/kernel.cfa

Timestamp:

Apr 11, 2019, 10:36:13 AM (5 years ago)

Author:

tdelisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, cleanup-dtors, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

3c06bba

Parents:

e8e457e

Message:

Fixed errno virtualization and enabled preemption during coroutine context switch

File:

• libcfa/src/concurrency/kernel.cfa (modified) (5 diffs)

libcfa/src/concurrency/kernel.cfa

@@ -91 +91 @@
 
 void ?{}( coroutine_desc & this, current_stack_info_t * info) with( this ) {
-        context.errno_ = 0;
         stack.storage = info->storage;
         with(*stack.storage) {
@@ -237 +236 @@
 }
 
+static int * __volatile_errno() __attribute__((noinline));
+static int * __volatile_errno() { asm(""); return &errno; }
+
 // KERNEL ONLY
 // runThread runs a thread by context switching
@@ -271 +273 @@
         thrd_src->state = thrd_src->state == Halted ? Halted : Inactive;
         proc_cor->state = Active;
+        int local_errno = *__volatile_errno();
 
         // set new coroutine that the processor is executing
@@ -280 +283 @@
         proc_cor->state = proc_cor->state == Halted ? Halted : Inactive;
         thrd_src->state = Active;
+        *__volatile_errno() = local_errno;
 }
 
@@ -380 +384 @@
         src->state = src->state == Halted ? Halted : Inactive;
 
-        // SKULLDUGGERY normally interrupts are enable before leaving a coroutine ctxswitch.
-        // Therefore, when first creating a coroutine, interrupts are enable before calling the main.
-        // This is consistent with thread creation. However, when creating the main processor coroutine,
-        // we wan't interrupts to be disabled. Therefore, we double-disable interrupts here so they will
-        // stay disabled.
-        disable_interrupts();
-
         // context switch to specified coroutine
         verify( dst->context.SP );