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-rw-r--r--arch/x86/include/asm/vgtod.h79
1 files changed, 33 insertions, 46 deletions
diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h
index fb856c9f0449..913a133f8e6f 100644
--- a/arch/x86/include/asm/vgtod.h
+++ b/arch/x86/include/asm/vgtod.h
@@ -5,33 +5,46 @@
#include <linux/compiler.h>
#include <linux/clocksource.h>
+#include <uapi/linux/time.h>
+
#ifdef BUILD_VDSO32_64
typedef u64 gtod_long_t;
#else
typedef unsigned long gtod_long_t;
#endif
+
+/*
+ * There is one of these objects in the vvar page for each
+ * vDSO-accelerated clockid. For high-resolution clocks, this encodes
+ * the time corresponding to vsyscall_gtod_data.cycle_last. For coarse
+ * clocks, this encodes the actual time.
+ *
+ * To confuse the reader, for high-resolution clocks, nsec is left-shifted
+ * by vsyscall_gtod_data.shift.
+ */
+struct vgtod_ts {
+ u64 sec;
+ u64 nsec;
+};
+
+#define VGTOD_BASES (CLOCK_TAI + 1)
+#define VGTOD_HRES (BIT(CLOCK_REALTIME) | BIT(CLOCK_MONOTONIC) | BIT(CLOCK_TAI))
+#define VGTOD_COARSE (BIT(CLOCK_REALTIME_COARSE) | BIT(CLOCK_MONOTONIC_COARSE))
+
/*
* 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 {
- unsigned seq;
-
- int vclock_mode;
- u64 cycle_last;
- u64 mask;
- u32 mult;
- u32 shift;
-
- /* open coded 'struct timespec' */
- u64 wall_time_snsec;
- gtod_long_t wall_time_sec;
- gtod_long_t monotonic_time_sec;
- u64 monotonic_time_snsec;
- 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;
+ unsigned int seq;
+
+ int vclock_mode;
+ u64 cycle_last;
+ u64 mask;
+ u32 mult;
+ u32 shift;
+
+ struct vgtod_ts basetime[VGTOD_BASES];
int tz_minuteswest;
int tz_dsttime;
@@ -44,9 +57,9 @@ static inline bool vclock_was_used(int vclock)
return READ_ONCE(vclocks_used) & (1 << vclock);
}
-static inline unsigned gtod_read_begin(const struct vsyscall_gtod_data *s)
+static inline unsigned int gtod_read_begin(const struct vsyscall_gtod_data *s)
{
- unsigned ret;
+ unsigned int ret;
repeat:
ret = READ_ONCE(s->seq);
@@ -59,7 +72,7 @@ repeat:
}
static inline int gtod_read_retry(const struct vsyscall_gtod_data *s,
- unsigned start)
+ unsigned int start)
{
smp_rmb();
return unlikely(s->seq != start);
@@ -77,30 +90,4 @@ static inline void gtod_write_end(struct vsyscall_gtod_data *s)
++s->seq;
}
-#ifdef CONFIG_X86_64
-
-#define VGETCPU_CPU_MASK 0xfff
-
-static inline unsigned int __getcpu(void)
-{
- unsigned int p;
-
- /*
- * Load per CPU data from GDT. LSL is faster than RDTSCP and
- * works on all CPUs. This is volatile so that it orders
- * correctly wrt barrier() and to keep gcc from cleverly
- * hoisting it out of the calling function.
- *
- * If RDPID is available, use it.
- */
- alternative_io ("lsl %[p],%[seg]",
- ".byte 0xf3,0x0f,0xc7,0xf8", /* RDPID %eax/rax */
- X86_FEATURE_RDPID,
- [p] "=a" (p), [seg] "r" (__PER_CPU_SEG));
-
- return p;
-}
-
-#endif /* CONFIG_X86_64 */
-
#endif /* _ASM_X86_VGTOD_H */