s390/vdso: add vdso support for coarse clocks

Add CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE optimization to
the 64-bit and 31-bit vdso.

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

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 4cef607f3711..69e980de0f62 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -232,6 +232,19 @@ void update_vsyscall(struct timekeeper *tk)
                 vdso_data->wtom_clock_nsec -= nsecps;
                 vdso_data->wtom_clock_sec++;
         }
+
+        vdso_data->xtime_coarse_sec = tk->xtime_sec;
+        vdso_data->xtime_coarse_nsec =
+                (long)(tk->tkr.xtime_nsec >> tk->tkr.shift);
+        vdso_data->wtom_coarse_sec =
+                vdso_data->xtime_coarse_sec + tk->wall_to_monotonic.tv_sec;
+        vdso_data->wtom_coarse_nsec =
+                vdso_data->xtime_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
+        while (vdso_data->wtom_coarse_nsec >= NSEC_PER_SEC) {
+                vdso_data->wtom_coarse_nsec -= NSEC_PER_SEC;
+                vdso_data->wtom_coarse_sec++;
+        }
+
         vdso_data->tk_mult = tk->tkr.mult;
         vdso_data->tk_shift = tk->tkr.shift;
         smp_wmb();