cooker, seitan: add sched_setscheduler

The sched_setscheduler requires to set the pid of the process we want to
change the priority, this adds a new metadata for getting the target pid
at runtime.

Add a couple of syscalls for the scheduler in the string parsing.

Signed-off-by: Alice Frosi <afrosi@redhat.com>

2 files changed, 53 insertions, 0 deletions

diff --git a/cooker/calls/scheduler.c b/cooker/calls/scheduler.c
new file mode 100644
index 0000000..436d3c2
--- /dev/null
+++ b/cooker/calls/scheduler.c
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2023 Red Hat GmbH
+ * Author: Alice Frosi <afrosi@redhat.com>
+ */
+#define _GNU_SOURCE
+#include <sys/syscall.h>
+#include <sched.h>
+
+#include "../cooker.h"
+#include "../calls.h"
+
+static struct num sched_policy[] = {
+	{ "SCHED_OTHER", SCHED_OTHER },
+	{ "SCHED_BATCH", SCHED_BATCH },
+	{ "SCHED_IDLE", SCHED_IDLE },
+	{ "SCHED_FIFO", SCHED_FIFO },
+	{ "SCHED_RR", SCHED_RR },
+	{ "SCHED_RESET_ON_FORK", SCHED_RESET_ON_FORK }, /* ORed in policy */
+	{ 0 },
+};
+
+static struct field sched_param[] = {
+	{ "sched_priority",
+	  INT,
+	  0,
+	  offsetof(struct sched_param, sched_priority),
+	  sizeof(int),
+	  { 0 } },
+	{ 0 },
+};
+
+static struct arg sched_setscheduler_args[] = {
+	{ 0, { "pid", PID, 0, 0, 0, { 0 } } },
+	{ 1, { "policy", INT, FLAGS, 0, 0, { .d_num = sched_policy } } },
+	{ 2, { "param", STRUCT, 0, 0, 0, { .d_struct = sched_param } } }
+};
+
+struct call syscalls_scheduler[] = {
+	{ __NR_sched_setscheduler, "sched_setscheduler", sched_setscheduler_args },
+	{ 0 },
+};
diff --git a/cooker/calls/scheduler.h b/cooker/calls/scheduler.h
new file mode 100644
index 0000000..751d65b
--- /dev/null
+++ b/cooker/calls/scheduler.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2023 Red Hat GmbH
+ * Author: Alice Frosi <afrosi@redhat.com>
+ */
+
+#ifndef CALLS_SCHEDULER_H
+#define CALLS_SCHEDULER_H
+
+extern struct call syscalls_scheduler[];
+
+#endif /* CALLS_IO_H */
+