From c941f07485e56e4b2653048e166b720428307acb Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Mon, 18 May 2015 23:42:26 +0200 Subject: [PATCH] target-s390x: simplify SCKC helper The clock comparator and the QEMU timer work the same way, triggering at a given time, they just differ by the origin and the scale. It is therefore possible to go from one to another without using the current clock value. This spares two calls to qemu_clock_get_ns, which probably return slightly different values, possibly reducing the accuracy. Signed-off-by: Aurelien Jarno Signed-off-by: Alexander Graf --- target-s390x/misc_helper.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/target-s390x/misc_helper.c b/target-s390x/misc_helper.c index 230bafdba2..120807f20b 100644 --- a/target-s390x/misc_helper.c +++ b/target-s390x/misc_helper.c @@ -291,12 +291,13 @@ void HELPER(sckc)(CPUS390XState *env, uint64_t time) return; } - /* difference between now and then */ - time -= clock_value(env); + /* difference between origins */ + time -= env->tod_offset; + /* nanoseconds */ time = tod2time(time); - timer_mod(env->tod_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + time); + timer_mod(env->tod_timer, env->tod_basetime + time); } /* Store Clock Comparator */ -- 2.11.4.GIT