Panic on events when the thread is preempted

When the thread is not running on the CPU it shouldn't be able to emit
events. A new emulation test ensures the emulation fails if it happens.

src/emu/nosv/event.c

@@ -555,6 +555,11 @@ process_ev(struct emu *emu)
 		return -1;
 	}
 
+	if (emu->thread->is_out_of_cpu) {
+		err("current thread %d out of CPU", emu->thread->tid);
+		return -1;
+	}
+
 	switch (emu->ev->c) {
 		case 'S':
 		case 'U':

src/emu/ovni/event.c

@@ -1,4 +1,4 @@
-/* Copyright (c) 2021-2023 Barcelona Supercomputing Center (BSC)
+/* Copyright (c) 2021-2024 Barcelona Supercomputing Center (BSC)
  * SPDX-License-Identifier: GPL-3.0-or-later */
 
 #include "ovni_priv.h"
@@ -458,6 +458,11 @@ model_ovni_event(struct emu *emu)
 		return -1;
 	}
 
+	if (emu->thread->is_out_of_cpu) {
+		err("current thread %d out of CPU", emu->thread->tid);
+		return -1;
+	}
+
 	switch (emu->ev->c) {
 		case 'H':
 			return pre_thread(emu);

test/emu/kernel/instr_kernel.h

@@ -0,0 +1,18 @@
+/* Copyright (c) 2024 Barcelona Supercomputing Center (BSC)
+ * SPDX-License-Identifier: GPL-3.0-or-later */
+
+#ifndef INSTR_KERNEL_H
+#define INSTR_KERNEL_H
+
+#include "instr.h"
+
+static inline void
+instr_kernel_init(void)
+{
+	instr_require("kernel");
+}
+
+INSTR_0ARG(instr_kernel_cs_out, "KCO")
+INSTR_0ARG(instr_kernel_cs_in,  "KCI")
+
+#endif /* INSTR_KERNEL_H */

test/emu/nosv/CMakeLists.txt

@@ -31,3 +31,6 @@ test_emu(bad-pause-parallel.c SHOULD_FAIL
   REGEX "body_pause: body(id=1,taskid=1) is not allowed to pause")
 test_emu(bad-nest-from-parallel.c SHOULD_FAIL
   REGEX "body_execute: cannot nest body(id=2,taskid=2) over body(id=1,taskid=1) which is already running")
+
+test_emu(events-from-outside-cpu.c SHOULD_FAIL
+  REGEX "current thread .* out of CPU")

test/emu/nosv/events-from-outside-cpu.c

@@ -0,0 +1,24 @@
+/* Copyright (c) 2024 Barcelona Supercomputing Center (BSC)
+ * SPDX-License-Identifier: GPL-3.0-or-later */
+
+#include <ovni.h>
+#include "instr_nosv.h"
+#include "../kernel/instr_kernel.h"
+
+int
+main(void)
+{
+	instr_start(0, 1);
+	instr_nosv_init();
+	instr_kernel_init();
+
+	/* Make the current thread out of CPU */
+	instr_kernel_cs_out();
+
+	/* Try to emit a nOS-V event: should fail */
+	instr_nosv_type_create(666);
+
+	instr_end();
+
+	return 0;
+}