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-rw-r--r--arch/sparc/include/asm/vvar.h75
1 files changed, 75 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/vvar.h b/arch/sparc/include/asm/vvar.h
new file mode 100644
index 000000000..6eaf5cfca
--- /dev/null
+++ b/arch/sparc/include/asm/vvar.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#ifndef _ASM_SPARC_VVAR_DATA_H
+#define _ASM_SPARC_VVAR_DATA_H
+
+#include <asm/clocksource.h>
+#include <asm/processor.h>
+#include <asm/barrier.h>
+#include <linux/time.h>
+#include <linux/types.h>
+
+struct vvar_data {
+ unsigned int seq;
+
+ int vclock_mode;
+ struct { /* extract of a clocksource struct */
+ u64 cycle_last;
+ u64 mask;
+ int mult;
+ int shift;
+ } clock;
+ /* open coded 'struct timespec' */
+ u64 wall_time_sec;
+ u64 wall_time_snsec;
+ u64 monotonic_time_snsec;
+ u64 monotonic_time_sec;
+ u64 monotonic_time_coarse_sec;
+ u64 monotonic_time_coarse_nsec;
+ u64 wall_time_coarse_sec;
+ u64 wall_time_coarse_nsec;
+
+ int tz_minuteswest;
+ int tz_dsttime;
+};
+
+extern struct vvar_data *vvar_data;
+extern int vdso_fix_stick;
+
+static inline unsigned int vvar_read_begin(const struct vvar_data *s)
+{
+ unsigned int ret;
+
+repeat:
+ ret = READ_ONCE(s->seq);
+ if (unlikely(ret & 1)) {
+ cpu_relax();
+ goto repeat;
+ }
+ smp_rmb(); /* Finish all reads before we return seq */
+ return ret;
+}
+
+static inline int vvar_read_retry(const struct vvar_data *s,
+ unsigned int start)
+{
+ smp_rmb(); /* Finish all reads before checking the value of seq */
+ return unlikely(s->seq != start);
+}
+
+static inline void vvar_write_begin(struct vvar_data *s)
+{
+ ++s->seq;
+ smp_wmb(); /* Makes sure that increment of seq is reflected */
+}
+
+static inline void vvar_write_end(struct vvar_data *s)
+{
+ smp_wmb(); /* Makes the value of seq current before we increment */
+ ++s->seq;
+}
+
+
+#endif /* _ASM_SPARC_VVAR_DATA_H */