kern/xcall: make sure functions are always run from interrupt context

3 files changed, 5 insertions, 12 deletions

diff --git a/kern/xcall.c b/kern/xcall.c
index b5ed4b24..9cef07a7 100644
--- a/kern/xcall.c
+++ b/kern/xcall.c
@@ -127,22 +127,13 @@ xcall_call(xcall_fn_t fn, void *arg, unsigned int cpu)
     struct xcall_cpu_data *local_data, *remote_data;
     struct xcall *call;
 
+    assert(cpu_intr_enabled());
     assert(fn != NULL);
 
     remote_data = percpu_ptr(xcall_cpu_data, cpu);
 
     thread_preempt_disable();
 
-    /* TODO Fix to match interrupt context semantics */
-    if (cpu == cpu_id()) {
-        unsigned long flags;
-
-        cpu_intr_save(&flags);
-        fn(arg);
-        cpu_intr_restore(flags);
-        goto out;
-    }
-
     local_data = xcall_cpu_data_get();
     call = xcall_cpu_data_get_send_call(local_data, cpu);
     xcall_set(call, fn, arg);
@@ -159,7 +150,6 @@ xcall_call(xcall_fn_t fn, void *arg, unsigned int cpu)
 
     spinlock_unlock(&remote_data->lock);
 
-out:
     thread_preempt_enable();
 }
 
diff --git a/kern/xcall.h b/kern/xcall.h
index 27b6af25..df364870 100644
--- a/kern/xcall.h
+++ b/kern/xcall.h
@@ -36,7 +36,8 @@ typedef void (*xcall_fn_t)(void *arg);
  * has finished running on the target processor, with the side effects of
  * the function visible.
  *
- * The function is run in interrupt context.
+ * The function is run in interrupt context. Interrupts must be enabled
+ * when calling this function.
  */
 void xcall_call(xcall_fn_t fn, void *arg, unsigned int cpu);
 
diff --git a/test/test_xcall.c b/test/test_xcall.c
index 4e02d6f3..f516401e 100644
--- a/test/test_xcall.c
+++ b/test/test_xcall.c
@@ -37,6 +37,8 @@ test_fn(void *arg)
 {
     (void)arg;
 
+    assert(thread_interrupted());
+
     printf("function called, running on cpu%u\n", cpu_id());
     test_done = 1;
 }