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(1, 0) int (*printk_func_t)(const char *fmt, va_list args); 20 21 int __printf(1, 0) vprintk_default(const char *fmt, va_list args); 22 23 #ifdef CONFIG_PRINTK_NMI 24 25 extern 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 */ 33 DECLARE_PER_CPU(printk_func_t, printk_func); 34 static 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 39 extern atomic_t nmi_message_lost; 40 static inline int get_nmi_message_lost(void) 41 { 42 return atomic_xchg(&nmi_message_lost, 0); 43 } 44 45 #else /* CONFIG_PRINTK_NMI */ 46 47 static inline __printf(1, 0) int vprintk_func(const char *fmt, va_list args) 48 { 49 return vprintk_default(fmt, args); 50 } 51 52 static inline int get_nmi_message_lost(void) 53 { 54 return 0; 55 } 56 57 #endif /* CONFIG_PRINTK_NMI */ 58