wrapper/trace-clock.c

   1 /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
   2  *
   3  * wrapper/trace-clock.c
   4  *
   5  * Contains LTTng trace clock mapping to LTTng trace clock or mainline monotonic
   6  * clock. This wrapper depends on CONFIG_HIGH_RES_TIMERS=y.
   7  *
   8  * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  */
  10
  11 #include <wrapper/trace-clock.h>
  12
  13 #ifdef LTTNG_USE_NMI_SAFE_CLOCK
  14 DEFINE_PER_CPU(u64, lttng_last_tsc);
  15 EXPORT_PER_CPU_SYMBOL(lttng_last_tsc);
  16 #endif /* #ifdef LTTNG_USE_NMI_SAFE_CLOCK */
  17
  18 #ifdef LTTNG_CLOCK_NMI_SAFE_BROKEN
  19 #warning "Your kernel implements a bogus nmi-safe clock source. Falling back to the non-nmi-safe clock source, which discards events traced from NMI context. Upgrade your kernel to resolve this situation."
  20 #endif