[S390] introduce vdso on s390

Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for
CLOCK_REALTIME/CLOCK_MONOTONIC.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 3d144e6020c6..e641f60bac99 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -6,6 +6,7 @@
 
 #include <linux/sched.h>
 #include <linux/kbuild.h>
+#include <asm/vdso.h>
 
 int main(void)
 {
@@ -38,5 +39,19 @@ int main(void)
         DEFINE(__SF_BACKCHAIN, offsetof(struct stack_frame, back_chain));
         DEFINE(__SF_GPRS, offsetof(struct stack_frame, gprs));
         DEFINE(__SF_EMPTY, offsetof(struct stack_frame, empty1));
+        BLANK();
+        /* timeval/timezone offsets for use by vdso */
+        DEFINE(__VDSO_UPD_COUNT, offsetof(struct vdso_data, tb_update_count));
+        DEFINE(__VDSO_XTIME_STAMP, offsetof(struct vdso_data, xtime_tod_stamp));
+        DEFINE(__VDSO_XTIME_SEC, offsetof(struct vdso_data, xtime_clock_sec));
+        DEFINE(__VDSO_XTIME_NSEC, offsetof(struct vdso_data, xtime_clock_nsec));
+        DEFINE(__VDSO_WTOM_SEC, offsetof(struct vdso_data, wtom_clock_sec));
+        DEFINE(__VDSO_WTOM_NSEC, offsetof(struct vdso_data, wtom_clock_nsec));
+        DEFINE(__VDSO_TIMEZONE, offsetof(struct vdso_data, tz_minuteswest));
+        /* constants used by the vdso */
+        DEFINE(CLOCK_REALTIME, CLOCK_REALTIME);
+        DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC);
+        DEFINE(CLOCK_REALTIME_RES, MONOTONIC_RES_NSEC);
+
         return 0;
 }