Merge branch 'for-next/bthreads'

4 files changed, 79 insertions, 8 deletions

diff --git a/include/bthread.h b/include/bthread.h
new file mode 100644
index 0000000000..e3871fb115
--- /dev/null
+++ b/include/bthread.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Ahmad Fatoum, Pengutronix
+ */
+
+#ifndef __BTHREAD_H_
+#define __BTHREAD_H_
+
+#include <linux/stddef.h>
+
+struct bthread;
+
+extern struct bthread *current;
+
+struct bthread *bthread_create(int (*threadfn)(void *), void *data, const char *namefmt, ...);
+void bthread_free(struct bthread *bthread);
+
+void bthread_schedule(struct bthread *);
+void bthread_wake(struct bthread *bthread);
+void bthread_suspend(struct bthread *bthread);
+int bthread_should_stop(void);
+int bthread_stop(struct bthread *bthread);
+void bthread_info(void);
+const char *bthread_name(struct bthread *bthread);
+bool bthread_is_main(struct bthread *bthread);
+
+/**
+ * bthread_run - create and wake a thread.
+ * @threadfn: the function to run for coming reschedule cycles
+ * @data: data ptr for @threadfn.
+ * @namefmt: printf-style name for the thread.
+ *
+ * Description: Convenient wrapper for bthread_create() followed by
+ * bthread_wakeup().  Returns the bthread or NULL
+ */
+#define bthread_run(threadfn, data, namefmt, ...)                          \
+({                                                                         \
+        struct bthread *__b                                                \
+                = bthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
+        if (__b)							   \
+                bthread_wake(__b);                                         \
+        __b;                                                               \
+})
+
+#ifdef CONFIG_BTHREAD
+void bthread_reschedule(void);
+#else
+static inline void bthread_reschedule(void)
+{
+}
+#endif
+
+#endif
diff --git a/include/poller.h b/include/poller.h
index db773265b2..371dafc6f8 100644
--- a/include/poller.h
+++ b/include/poller.h
@@ -39,6 +39,8 @@ static inline bool poller_async_active(struct poller_async *pa)
 	return pa->active;
 }
 
+extern int poller_active;
+
 #ifdef CONFIG_POLLER
 void poller_call(void);
 #else
diff --git a/include/sched.h b/include/sched.h
new file mode 100644
index 0000000000..57be1678fd
--- /dev/null
+++ b/include/sched.h
@@ -0,0 +1,15 @@
+/* SPDX License Identifier: GPL-2.0 */
+#ifndef __BAREBOX_SCHED_H_
+#define __BAREBOX_SCHED_H_
+
+#include <bthread.h>
+#include <poller.h>
+
+static inline void resched(void)
+{
+	poller_call();
+	if (!IS_ENABLED(CONFIG_POLLER) || !poller_active)
+		bthread_reschedule();
+}
+
+#endif
diff --git a/include/slice.h b/include/slice.h
index b2d65b80cd..cf684300a8 100644
--- a/include/slice.h
+++ b/include/slice.h
@@ -1,6 +1,8 @@
 #ifndef __SLICE_H
 #define __SLICE_H
 
+#include <bthread.h>
+
 enum slice_action {
 	SLICE_ACQUIRE = 1,
 	SLICE_RELEASE = -1,
@@ -35,12 +37,11 @@ void command_slice_release(void);
 
 extern int poller_active;
 
-#ifdef CONFIG_POLLER
-#define assert_command_context() ({    \
-	WARN_ONCE(poller_active, "%s called in poller\n", __func__); \
-})
-#else
-#define assert_command_context() do { } while (0)
-#endif
+#define assert_command_context() do { \
+	WARN_ONCE(IS_ENABLED(CONFIG_POLLER) && poller_active, \
+		  "%s called in poller\n", __func__); \
+	WARN_ONCE(IS_ENABLED(CONFIG_BTHREAD) && !bthread_is_main(current), \
+		  "%s called in secondary bthread\n", __func__); \
+} while (0)
 
-#endif /* __SLICE_H */
+#endif