LXR linux/kernel/printk/internal.h

   1/*
   2 * internal.h - printk internal definitions
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License
   6 * as published by the Free Software Foundation; either version 2
   7 * of the License, or (at your option) any later version.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17#include <linux/percpu.h>
  18
  19typedef __printf(1, 0) int (*printk_func_t)(const char *fmt, va_list args);
  20
  21int __printf(1, 0) vprintk_default(const char *fmt, va_list args);
  22
  23#ifdef CONFIG_PRINTK_NMI
  24
  25extern raw_spinlock_t logbuf_lock;
  26
  27/*
  28 * printk() could not take logbuf_lock in NMI context. Instead,
  29 * it temporary stores the strings into a per-CPU buffer.
  30 * The alternative implementation is chosen transparently
  31 * via per-CPU variable.
  32 */
  33DECLARE_PER_CPU(printk_func_t, printk_func);
  34static inline __printf(1, 0) int vprintk_func(const char *fmt, va_list args)
  35{
  36        return this_cpu_read(printk_func)(fmt, args);
  37}
  38
  39extern atomic_t nmi_message_lost;
  40static inline int get_nmi_message_lost(void)
  41{
  42        return atomic_xchg(&nmi_message_lost, 0);
  43}
  44
  45#else /* CONFIG_PRINTK_NMI */
  46
  47static inline __printf(1, 0) int vprintk_func(const char *fmt, va_list args)
  48{
  49        return vprintk_default(fmt, args);
  50}
  51
  52static inline int get_nmi_message_lost(void)
  53{
  54        return 0;
  55}
  56
  57#endif /* CONFIG_PRINTK_NMI */
  58