1 /**************************************************************************** 2 **************************************************************************** 3 *** 4 *** This header was automatically generated from a Linux kernel header 5 *** of the same name, to make information necessary for userspace to 6 *** call into the kernel available to libc. It contains only constants, 7 *** structures, and macros generated from the original header, and thus, 8 *** contains no copyrightable information. 9 *** 10 **************************************************************************** 11 ****************************************************************************/ 12 #ifndef __LINUX_SEQLOCK_H 13 #define __LINUX_SEQLOCK_H 14 15 #include <linux/spinlock.h> 16 #include <linux/preempt.h> 17 18 typedef struct { 19 unsigned sequence; 20 spinlock_t lock; 21 } seqlock_t; 22 23 #define __SEQLOCK_UNLOCKED(lockname) { 0, __SPIN_LOCK_UNLOCKED(lockname) } 24 25 #define SEQLOCK_UNLOCKED __SEQLOCK_UNLOCKED(old_style_seqlock_init) 26 27 #define seqlock_init(x) do { *(x) = (seqlock_t) __SEQLOCK_UNLOCKED(x); } while (0) 28 29 #define DEFINE_SEQLOCK(x) seqlock_t x = __SEQLOCK_UNLOCKED(x) 30 31 #define SEQCNT_ZERO { 0 } 32 #define seqcount_init(x) do { *(x) = (seqcount_t) SEQCNT_ZERO; } while (0) 33 34 #define write_seqlock_irqsave(lock, flags) do { local_irq_save(flags); write_seqlock(lock); } while (0) 35 #define write_seqlock_irq(lock) do { local_irq_disable(); write_seqlock(lock); } while (0) 36 #define write_seqlock_bh(lock) do { local_bh_disable(); write_seqlock(lock); } while (0) 37 #define write_sequnlock_irqrestore(lock, flags) do { write_sequnlock(lock); local_irq_restore(flags); } while(0) 38 #define write_sequnlock_irq(lock) do { write_sequnlock(lock); local_irq_enable(); } while(0) 39 #define write_sequnlock_bh(lock) do { write_sequnlock(lock); local_bh_enable(); } while(0) 40 #define read_seqbegin_irqsave(lock, flags) ({ local_irq_save(flags); read_seqbegin(lock); }) 41 #define read_seqretry_irqrestore(lock, iv, flags) ({ int ret = read_seqretry(lock, iv); local_irq_restore(flags); ret; }) 42 #endif 43
