Cleanup: move to kernel style SPDX license identifiers

[lttng-modules.git] / wrapper / timer.h

diff --git a/wrapper/timer.h b/wrapper/timer.h
index 441a01723c33f27df5ecf7945ac999ec4c93daf3..a115cf301fd527e10f4caa6a797d98a4bcd5271c 100644 (file)
--- a/wrapper/timer.h
+++ b/wrapper/timer.h
@@ -1,55 +1,89 @@
-#ifndef _LTTNG_WRAPPER_TIMER_H
-#define _LTTNG_WRAPPER_TIMER_H
-
-/*
+/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
+ *
  * wrapper/timer.h
  *
  * wrapper around linux/timer.h.
  *
  * Copyright (C) 2016 Michael Jeanson <mjeanson@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#ifndef _LTTNG_WRAPPER_TIMER_H
+#define _LTTNG_WRAPPER_TIMER_H
+
 #include <linux/version.h>
 #include <linux/timer.h>
 #include <lttng-kernel-version.h>
 
+/*
+ * In the olden days, pinned timers were initialized normaly with init_timer()
+ * and then modified with mod_timer_pinned().
+ *
+ * Then came kernel 4.8.0 and they had to be initilized as pinned with
+ * init_timer_pinned() and then modified as regular timers with mod_timer().
+ *
+ * Then came kernel 4.15.0 with a new timer API where init_timer() is no more.
+ * It's replaced by timer_setup() where pinned is now part of timer flags.
+ */
+
 
-#if (LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8))
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0))
 
-#define lttng_init_timer_pinned(timer)                                 \
+#define LTTNG_TIMER_PINNED             TIMER_PINNED
+#define LTTNG_TIMER_FUNC_ARG_TYPE      struct timer_list *
+
+#define lttng_mod_timer_pinned(timer, expires) \
+       mod_timer(timer, expires)
+
+#define lttng_from_timer(var, callback_timer, timer_fieldname) \
+       from_timer(var, callback_timer, timer_fieldname)
+
+#define lttng_timer_setup(timer, callback, flags, unused) \
+       timer_setup(timer, callback, flags)
+
+
+#else /* LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0) */
+
+
+# if (LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) \
+       || LINUX_VERSION_CODE >= KERNEL_VERSION(4,8,0))
+
+#define lttng_init_timer_pinned(timer) \
        init_timer_pinned(timer)
 
-static inline int lttng_mod_timer_pinned(struct timer_list *timer,
-               unsigned long expires)
-{
-       return mod_timer(timer, expires);
-}
+#define lttng_mod_timer_pinned(timer, expires) \
+       mod_timer(timer, expires)
 
-#else /* #if (LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8)) */
+# else /* LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) */
 
-#define lttng_init_timer_pinned(timer)                                 \
+#define lttng_init_timer_pinned(timer) \
        init_timer(timer)
 
-static inline int lttng_mod_timer_pinned(struct timer_list *timer,
-               unsigned long expires)
+#define lttng_mod_timer_pinned(timer, expires) \
+       mod_timer_pinned(timer, expires)
+
+# endif /* LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) */
+
+
+#define LTTNG_TIMER_PINNED             TIMER_PINNED
+#define LTTNG_TIMER_FUNC_ARG_TYPE      unsigned long
+
+/* timer_fieldname is unused prior to 4.15. */
+#define lttng_from_timer(var, timer_data, timer_fieldname) \
+       ((typeof(var))timer_data)
+
+static inline void lttng_timer_setup(struct timer_list *timer,
+               void (*function)(LTTNG_TIMER_FUNC_ARG_TYPE),
+               unsigned int flags, void *data)
 {
-       return mod_timer_pinned(timer, expires);
+       if (flags & LTTNG_TIMER_PINNED)
+               lttng_init_timer_pinned(timer);
+       else
+               init_timer(timer);
+
+       timer->function = function;
+       timer->data = (unsigned long)data;
 }
 
-#endif /* #else #if (LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8)) */
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0) */
 
 #endif /* _LTTNG_WRAPPER_TIMER_H */