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