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
  19 #ifdef CONFIG_PRINTK
  20
  21 #define PRINTK_SAFE_CONTEXT_MASK        0x7fffffff
  22 #define PRINTK_NMI_CONTEXT_MASK 0x80000000
  23
  24 extern raw_spinlock_t logbuf_lock;
  25
  26 __printf(1, 0) int vprintk_default(const char *fmt, va_list args);
  27 __printf(1, 0) int vprintk_func(const char *fmt, va_list args);
  28 void __printk_safe_enter(void);
  29 void __printk_safe_exit(void);
  30
  31 #define printk_safe_enter_irqsave(flags)        \
  32         do {                                    \
  33                 local_irq_save(flags);          \
  34                 __printk_safe_enter();          \
  35         } while (0)
  36
  37 #define printk_safe_exit_irqrestore(flags)      \
  38         do {                                    \
  39                 __printk_safe_exit();           \
  40                 local_irq_restore(flags);       \
  41         } while (0)
  42
  43 #define printk_safe_enter_irq()         \
  44         do {                                    \
  45                 local_irq_disable();            \
  46                 __printk_safe_enter();          \
  47         } while (0)
  48
  49 #define printk_safe_exit_irq()                  \
  50         do {                                    \
  51                 __printk_safe_exit();           \
  52                 local_irq_enable();             \
  53         } while (0)
  54
  55 #else
  56
  57 __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
  58
  59 /*
  60  * In !PRINTK builds we still export logbuf_lock spin_lock, console_sem
  61  * semaphore and some of console functions (console_unlock()/etc.), so
  62  * printk-safe must preserve the existing local IRQ guarantees.
  63  */
  64 #define printk_safe_enter_irqsave(flags) local_irq_save(flags)
  65 #define printk_safe_exit_irqrestore(flags) local_irq_restore(flags)
  66
  67 #define printk_safe_enter_irq() local_irq_disable()
  68 #define printk_safe_exit_irq() local_irq_enable()
  69
  70 #endif /* CONFIG_PRINTK */