mirror of https://gitee.com/openkylin/linux.git
75 lines
1.5 KiB
C
75 lines
1.5 KiB
C
/*
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* Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
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*/
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#ifndef _ASM_SPARC_VVAR_DATA_H
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#define _ASM_SPARC_VVAR_DATA_H
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#include <asm/clocksource.h>
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#include <linux/seqlock.h>
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#include <linux/time.h>
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#include <linux/types.h>
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struct vvar_data {
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unsigned int seq;
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int vclock_mode;
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struct { /* extract of a clocksource struct */
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u64 cycle_last;
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u64 mask;
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int mult;
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int shift;
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} clock;
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/* open coded 'struct timespec' */
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u64 wall_time_sec;
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u64 wall_time_snsec;
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u64 monotonic_time_snsec;
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u64 monotonic_time_sec;
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u64 monotonic_time_coarse_sec;
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u64 monotonic_time_coarse_nsec;
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u64 wall_time_coarse_sec;
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u64 wall_time_coarse_nsec;
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int tz_minuteswest;
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int tz_dsttime;
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};
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extern struct vvar_data *vvar_data;
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extern int vdso_fix_stick;
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static inline unsigned int vvar_read_begin(const struct vvar_data *s)
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{
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unsigned int ret;
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repeat:
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ret = READ_ONCE(s->seq);
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if (unlikely(ret & 1)) {
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cpu_relax();
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goto repeat;
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}
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smp_rmb(); /* Finish all reads before we return seq */
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return ret;
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}
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static inline int vvar_read_retry(const struct vvar_data *s,
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unsigned int start)
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{
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smp_rmb(); /* Finish all reads before checking the value of seq */
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return unlikely(s->seq != start);
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}
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static inline void vvar_write_begin(struct vvar_data *s)
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{
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++s->seq;
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smp_wmb(); /* Makes sure that increment of seq is reflected */
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}
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static inline void vvar_write_end(struct vvar_data *s)
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{
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smp_wmb(); /* Makes the value of seq current before we increment */
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++s->seq;
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}
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#endif /* _ASM_SPARC_VVAR_DATA_H */
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