restructure project

kernels/thread-os/Makefile

@@ -0,0 +1,3 @@
+NAME = thread-os
+SRCS = thread-os.c
+include $(AM_HOME)/Makefile

kernels/thread-os/thread-os.c

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+#include <am.h>
+#include <klib.h>
+#include <klib-macros.h>
+
+#define MAX_CPU 8
+
+typedef union task {
+  struct {
+    const char *name;
+    union task *next;
+    void      (*entry)(void *);
+    Context    *context;
+  };
+  uint8_t stack[8192];
+} Task;
+
+Task *currents[MAX_CPU];
+#define current currents[cpu_current()]
+
+// user-defined tasks
+
+int locked = 0;
+void lock()   { while (atomic_xchg(&locked, 1)); }
+void unlock() { atomic_xchg(&locked, 0); }
+
+void func(void *arg) {
+  while (1) {
+    lock();
+    printf("Thread-%s on CPU #%d\n", arg, cpu_current());
+    unlock();
+    for (int volatile i = 0; i < 100000; i++) ;
+  }
+}
+
+Task tasks[] = {
+  { .name = "A", .entry = func },
+  { .name = "B", .entry = func },
+  { .name = "C", .entry = func },
+  { .name = "D", .entry = func },
+  { .name = "E", .entry = func },
+};
+
+// ------------------
+
+Context *on_interrupt(Event ev, Context *ctx) {
+  extern Task tasks[];
+  if (!current) current = &tasks[0];
+  else          current->context = ctx;
+  do {
+    current = current->next;
+  } while ((current - tasks) % cpu_count() != cpu_current());
+  return current->context;
+}
+
+void mp_entry() {
+  iset(true);
+  yield();
+}
+
+int main() {
+  ioe_init();
+  cte_init(on_interrupt);
+
+  for (int i = 0; i < LENGTH(tasks); i++) {
+    Task *task    = &tasks[i];
+    Area stack    = (Area) { &task->context + 1, task + 1 };
+    task->context = kcontext(stack, task->entry, (void *)task->name);
+    task->next    = &tasks[(i + 1) % LENGTH(tasks)];
+  }
+  mpe_init(mp_entry);
+}