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 typedef __printf(2, 0) int (*printk_func_t)(int level, const char *fmt, 20 va_list args); 21 22 __printf(2, 0) 23 int vprintk_default(int level, const char *fmt, va_list args); 24 25 #ifdef CONFIG_PRINTK_NMI 26 27 extern raw_spinlock_t logbuf_lock; 28 29 /* 30 * printk() could not take logbuf_lock in NMI context. Instead, 31 * it temporary stores the strings into a per-CPU buffer. 32 * The alternative implementation is chosen transparently 33 * via per-CPU variable. 34 */ 35 DECLARE_PER_CPU(printk_func_t, printk_func); 36 __printf(2, 0) 37 static inline int vprintk_func(int level, const char *fmt, va_list args) 38 { 39 return this_cpu_read(printk_func)(level, fmt, args); 40 } 41 42 extern atomic_t nmi_message_lost; 43 static inline int get_nmi_message_lost(void) 44 { 45 return atomic_xchg(&nmi_message_lost, 0); 46 } 47 48 #else /* CONFIG_PRINTK_NMI */ 49 50 __printf(2, 0) 51 static inline int vprintk_func(int level, const char *fmt, va_list args) 52 { 53 return vprintk_default(level, fmt, args); 54 } 55 56 static inline int get_nmi_message_lost(void) 57 { 58 return 0; 59 } 60 61 #endif /* CONFIG_PRINTK_NMI */ 62