1 files changed, 57 insertions, 14 deletions

diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h
index 46e24d36b7da..3c3366c2e37f 100644
--- a/arch/x86/include/asm/vgtod.h
+++ b/arch/x86/include/asm/vgtod.h
@@ -1,30 +1,73 @@
 #ifndef _ASM_X86_VGTOD_H
 #define _ASM_X86_VGTOD_H
 
-#include <asm/vsyscall.h>
+#include <linux/compiler.h>
 #include <linux/clocksource.h>
 
+#ifdef BUILD_VDSO32_64
+typedef u64 gtod_long_t;
+#else
+typedef unsigned long gtod_long_t;
+#endif
+/*
+ * vsyscall_gtod_data will be accessed by 32 and 64 bit code at the same time
+ * so be carefull by modifying this structure.
+ */
 struct vsyscall_gtod_data {
-        seqcount_t      seq;
+        unsigned seq;
 
-        struct { /* extract of a clocksource struct */
-                int vclock_mode;
-                cycle_t cycle_last;
-                cycle_t mask;
-                u32     mult;
-                u32     shift;
-        } clock;
+        int vclock_mode;
+        cycle_t cycle_last;
+        cycle_t mask;
+        u32     mult;
+        u32     shift;
 
         /* open coded 'struct timespec' */
-        time_t          wall_time_sec;
         u64             wall_time_snsec;
+        gtod_long_t     wall_time_sec;
+        gtod_long_t     monotonic_time_sec;
         u64             monotonic_time_snsec;
-        time_t          monotonic_time_sec;
+        gtod_long_t     wall_time_coarse_sec;
+        gtod_long_t     wall_time_coarse_nsec;
+        gtod_long_t     monotonic_time_coarse_sec;
+        gtod_long_t     monotonic_time_coarse_nsec;
 
-        struct timezone sys_tz;
-        struct timespec wall_time_coarse;
-        struct timespec monotonic_time_coarse;
+        int             tz_minuteswest;
+        int             tz_dsttime;
 };
 extern struct vsyscall_gtod_data vsyscall_gtod_data;
 
+static inline unsigned gtod_read_begin(const struct vsyscall_gtod_data *s)
+{
+        unsigned ret;
+
+repeat:
+        ret = ACCESS_ONCE(s->seq);
+        if (unlikely(ret & 1)) {
+                cpu_relax();
+                goto repeat;
+        }
+        smp_rmb();
+        return ret;
+}
+
+static inline int gtod_read_retry(const struct vsyscall_gtod_data *s,
+                                        unsigned start)
+{
+        smp_rmb();
+        return unlikely(s->seq != start);
+}
+
+static inline void gtod_write_begin(struct vsyscall_gtod_data *s)
+{
+        ++s->seq;
+        smp_wmb();
+}
+
+static inline void gtod_write_end(struct vsyscall_gtod_data *s)
+{
+        smp_wmb();
+        ++s->seq;
+}
+
 #endif /* _ASM_X86_VGTOD_H */