include/wrapper/timer.h

   1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
   2  *
   3  * wrapper/timer.h
   4  *
   5  * wrapper around linux/timer.h.
   6  *
   7  * Copyright (C) 2016 Michael Jeanson <mjeanson@efficios.com>
   8  */
   9
  10 #ifndef _LTTNG_WRAPPER_TIMER_H
  11 #define _LTTNG_WRAPPER_TIMER_H
  12
  13 #include <lttng/kernel-version.h>
  14 #include <linux/timer.h>
  15
  16 /*
  17  * In the olden days, pinned timers were initialized normaly with init_timer()
  18  * and then modified with mod_timer_pinned().
  19  *
  20  * Then came kernel 4.8.0 and they had to be initilized as pinned with
  21  * init_timer_pinned() and then modified as regular timers with mod_timer().
  22  *
  23  * Then came kernel 4.15.0 with a new timer API where init_timer() is no more.
  24  * It's replaced by timer_setup() where pinned is now part of timer flags.
  25  */
  26
  27
  28 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,15,0))
  29
  30 #define LTTNG_TIMER_PINNED              TIMER_PINNED
  31 #define LTTNG_TIMER_FUNC_ARG_TYPE       struct timer_list *
  32
  33 #define lttng_mod_timer_pinned(timer, expires) \
  34         mod_timer(timer, expires)
  35
  36 #define lttng_from_timer(var, callback_timer, timer_fieldname) \
  37         from_timer(var, callback_timer, timer_fieldname)
  38
  39 #define lttng_timer_setup(timer, callback, flags, unused) \
  40         timer_setup(timer, callback, flags)
  41
  42
  43 #else /* LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,15,0) */
  44
  45
  46 # if (LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) \
  47         || LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,8,0))
  48
  49 #define lttng_init_timer_pinned(timer) \
  50         init_timer_pinned(timer)
  51
  52 #define lttng_mod_timer_pinned(timer, expires) \
  53         mod_timer(timer, expires)
  54
  55 # else /* LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) */
  56
  57 #define lttng_init_timer_pinned(timer) \
  58         init_timer(timer)
  59
  60 #define lttng_mod_timer_pinned(timer, expires) \
  61         mod_timer_pinned(timer, expires)
  62
  63 # endif /* LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) */
  64
  65
  66 #define LTTNG_TIMER_PINNED              TIMER_PINNED
  67 #define LTTNG_TIMER_FUNC_ARG_TYPE       unsigned long
  68
  69 /* timer_fieldname is unused prior to 4.15. */
  70 #define lttng_from_timer(var, timer_data, timer_fieldname) \
  71         ((typeof(var))timer_data)
  72
  73 static inline void lttng_timer_setup(struct timer_list *timer,
  74                 void (*function)(LTTNG_TIMER_FUNC_ARG_TYPE),
  75                 unsigned int flags, void *data)
  76 {
  77         if (flags & LTTNG_TIMER_PINNED)
  78                 lttng_init_timer_pinned(timer);
  79         else
  80                 init_timer(timer);
  81
  82         timer->function = function;
  83         timer->data = (unsigned long)data;
  84 }
  85
  86 #endif /* LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,15,0) */
  87
  88 #endif /* _LTTNG_WRAPPER_TIMER_H */