wrapper/timer.h

   1 #ifndef _LTTNG_WRAPPER_TIMER_H
   2 #define _LTTNG_WRAPPER_TIMER_H
   3
   4 /*
   5  * wrapper/timer.h
   6  *
   7  * wrapper around linux/timer.h.
   8  *
   9  * Copyright (C) 2016 Michael Jeanson <mjeanson@efficios.com>
  10  *
  11  * This library is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License as published by the Free Software Foundation; only
  14  * version 2.1 of the License.
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19  * Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public
  22  * License along with this library; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  24  */
  25
  26 #include <linux/version.h>
  27 #include <linux/timer.h>
  28 #include <lttng-kernel-version.h>
  29
  30 /*
  31  * In the olden days, pinned timers were initialized normaly with init_timer()
  32  * and then modified with mod_timer_pinned().
  33  *
  34  * Then came kernel 4.8.0 and they had to be initilized as pinned with
  35  * init_timer_pinned() and then modified as regular timers with mod_timer().
  36  *
  37  * Then came kernel 4.15.0 with a new timer API where init_timer() is no more.
  38  * It's replaced by timer_setup() where pinned is now part of timer flags.
  39  */
  40
  41
  42 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0))
  43
  44 #define LTTNG_TIMER_PINNED              TIMER_PINNED
  45 #define LTTNG_TIMER_FUNC_ARG_TYPE       struct timer_list *
  46
  47 #define lttng_mod_timer_pinned(timer, expires) \
  48         mod_timer(timer, expires)
  49
  50 #define lttng_from_timer(var, callback_timer, timer_fieldname) \
  51         from_timer(var, callback_timer, timer_fieldname)
  52
  53 #define lttng_timer_setup(timer, callback, flags, unused) \
  54         timer_setup(timer, callback, flags)
  55
  56
  57 #else /* LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0) */
  58
  59
  60 # if (LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) \
  61         || LINUX_VERSION_CODE >= KERNEL_VERSION(4,8,0))
  62
  63 #define lttng_init_timer_pinned(timer) \
  64         init_timer_pinned(timer)
  65
  66 #define lttng_mod_timer_pinned(timer, expires) \
  67         mod_timer(timer, expires)
  68
  69 # else /* LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) */
  70
  71 #define lttng_init_timer_pinned(timer) \
  72         init_timer(timer)
  73
  74 #define lttng_mod_timer_pinned(timer, expires) \
  75         mod_timer_pinned(timer, expires)
  76
  77 # endif /* LTTNG_RT_VERSION_CODE >= LTTNG_RT_KERNEL_VERSION(4,6,4,8) */
  78
  79
  80 #define LTTNG_TIMER_PINNED              TIMER_PINNED
  81 #define LTTNG_TIMER_FUNC_ARG_TYPE       unsigned long
  82
  83 /* timer_fieldname is unused prior to 4.15. */
  84 #define lttng_from_timer(var, timer_data, timer_fieldname) \
  85         ((typeof(var))timer_data)
  86
  87 static inline void lttng_timer_setup(struct timer_list *timer,
  88                 void (*function)(LTTNG_TIMER_FUNC_ARG_TYPE),
  89                 unsigned int flags, void *data)
  90 {
  91         if (flags & LTTNG_TIMER_PINNED)
  92                 lttng_init_timer_pinned(timer);
  93         else
  94                 init_timer(timer);
  95
  96         timer->function = function;
  97         timer->data = (unsigned long)data;
  98 }
  99
 100 #endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(4,15,0) */
 101
 102 #endif /* _LTTNG_WRAPPER_TIMER_H */