summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/time.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/s390/kernel/time.c')
-rw-r--r--arch/s390/kernel/time.c318
1 files changed, 214 insertions, 104 deletions
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 513e59d08a55..0ac30ee2c633 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -41,6 +41,9 @@
#include <linux/gfp.h>
#include <linux/kprobes.h>
#include <linux/uaccess.h>
+#include <vdso/vsyscall.h>
+#include <vdso/clocksource.h>
+#include <vdso/helpers.h>
#include <asm/facility.h>
#include <asm/delay.h>
#include <asm/div64.h>
@@ -84,7 +87,7 @@ void __init time_early_init(void)
/* Initialize TOD steering parameters */
tod_steering_end = *(unsigned long long *) &tod_clock_base[1];
- vdso_data->ts_end = tod_steering_end;
+ vdso_data->arch_data.tod_steering_end = tod_steering_end;
if (!test_facility(28))
return;
@@ -257,6 +260,7 @@ static struct clocksource clocksource_tod = {
.mult = 1000,
.shift = 12,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .vdso_clock_mode = VDSO_CLOCKMODE_TOD,
};
struct clocksource * __init clocksource_default_clock(void)
@@ -264,56 +268,6 @@ struct clocksource * __init clocksource_default_clock(void)
return &clocksource_tod;
}
-void update_vsyscall(struct timekeeper *tk)
-{
- u64 nsecps;
-
- if (tk->tkr_mono.clock != &clocksource_tod)
- return;
-
- /* Make userspace gettimeofday spin until we're done. */
- ++vdso_data->tb_update_count;
- smp_wmb();
- vdso_data->xtime_tod_stamp = tk->tkr_mono.cycle_last;
- vdso_data->xtime_clock_sec = tk->xtime_sec;
- vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec;
- vdso_data->wtom_clock_sec =
- tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
- vdso_data->wtom_clock_nsec = tk->tkr_mono.xtime_nsec +
- + ((u64) tk->wall_to_monotonic.tv_nsec << tk->tkr_mono.shift);
- nsecps = (u64) NSEC_PER_SEC << tk->tkr_mono.shift;
- while (vdso_data->wtom_clock_nsec >= nsecps) {
- 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_mono.xtime_nsec >> tk->tkr_mono.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_mono.mult;
- vdso_data->tk_shift = tk->tkr_mono.shift;
- vdso_data->hrtimer_res = hrtimer_resolution;
- smp_wmb();
- ++vdso_data->tb_update_count;
-}
-
-extern struct timezone sys_tz;
-
-void update_vsyscall_tz(void)
-{
- vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
- vdso_data->tz_dsttime = sys_tz.tz_dsttime;
-}
-
/*
* Initialize the TOD clock and the CPU timer of
* the boot cpu.
@@ -342,11 +296,12 @@ void __init time_init(void)
}
static DEFINE_PER_CPU(atomic_t, clock_sync_word);
-static DEFINE_MUTEX(clock_sync_mutex);
+static DEFINE_MUTEX(stp_mutex);
static unsigned long clock_sync_flags;
-#define CLOCK_SYNC_HAS_STP 0
-#define CLOCK_SYNC_STP 1
+#define CLOCK_SYNC_HAS_STP 0
+#define CLOCK_SYNC_STP 1
+#define CLOCK_SYNC_STPINFO_VALID 2
/*
* The get_clock function for the physical clock. It will get the current
@@ -431,7 +386,6 @@ static void clock_sync_global(unsigned long long delta)
/* Epoch overflow */
tod_clock_base[0]++;
/* Adjust TOD steering parameters. */
- vdso_data->tb_update_count++;
now = get_tod_clock();
adj = tod_steering_end - now;
if (unlikely((s64) adj >= 0))
@@ -443,9 +397,8 @@ static void clock_sync_global(unsigned long long delta)
panic("TOD clock sync offset %lli is too large to drift\n",
tod_steering_delta);
tod_steering_end = now + (abs(tod_steering_delta) << 15);
- vdso_data->ts_dir = (tod_steering_delta < 0) ? 0 : 1;
- vdso_data->ts_end = tod_steering_end;
- vdso_data->tb_update_count++;
+ vdso_data->arch_data.tod_steering_end = tod_steering_end;
+
/* Update LPAR offset. */
if (ptff_query(PTFF_QTO) && ptff(&qto, sizeof(qto), PTFF_QTO) == 0)
lpar_offset = qto.tod_epoch_difference;
@@ -492,7 +445,6 @@ static struct stp_sstpi stp_info;
static void *stp_page;
static void stp_work_fn(struct work_struct *work);
-static DEFINE_MUTEX(stp_work_mutex);
static DECLARE_WORK(stp_work, stp_work_fn);
static struct timer_list stp_timer;
@@ -583,10 +535,26 @@ void stp_queue_work(void)
queue_work(time_sync_wq, &stp_work);
}
+static int __store_stpinfo(void)
+{
+ int rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi));
+
+ if (rc)
+ clear_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags);
+ else
+ set_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags);
+ return rc;
+}
+
+static int stpinfo_valid(void)
+{
+ return stp_online && test_bit(CLOCK_SYNC_STPINFO_VALID, &clock_sync_flags);
+}
+
static int stp_sync_clock(void *data)
{
struct clock_sync_data *sync = data;
- unsigned long long clock_delta;
+ unsigned long long clock_delta, flags;
static int first;
int rc;
@@ -599,16 +567,17 @@ static int stp_sync_clock(void *data)
if (stp_info.todoff[0] || stp_info.todoff[1] ||
stp_info.todoff[2] || stp_info.todoff[3] ||
stp_info.tmd != 2) {
+ flags = vdso_update_begin();
rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0,
&clock_delta);
if (rc == 0) {
sync->clock_delta = clock_delta;
clock_sync_global(clock_delta);
- rc = chsc_sstpi(stp_page, &stp_info,
- sizeof(struct stp_sstpi));
+ rc = __store_stpinfo();
if (rc == 0 && stp_info.tmd != 2)
rc = -EAGAIN;
}
+ vdso_update_end(flags);
}
sync->in_sync = rc ? -EAGAIN : 1;
xchg(&first, 0);
@@ -628,6 +597,81 @@ static int stp_sync_clock(void *data)
return 0;
}
+static int stp_clear_leap(void)
+{
+ struct __kernel_timex txc;
+ int ret;
+
+ memset(&txc, 0, sizeof(txc));
+
+ ret = do_adjtimex(&txc);
+ if (ret < 0)
+ return ret;
+
+ txc.modes = ADJ_STATUS;
+ txc.status &= ~(STA_INS|STA_DEL);
+ return do_adjtimex(&txc);
+}
+
+static void stp_check_leap(void)
+{
+ struct stp_stzi stzi;
+ struct stp_lsoib *lsoib = &stzi.lsoib;
+ struct __kernel_timex txc;
+ int64_t timediff;
+ int leapdiff, ret;
+
+ if (!stp_info.lu || !check_sync_clock()) {
+ /*
+ * Either a scheduled leap second was removed by the operator,
+ * or STP is out of sync. In both cases, clear the leap second
+ * kernel flags.
+ */
+ if (stp_clear_leap() < 0)
+ pr_err("failed to clear leap second flags\n");
+ return;
+ }
+
+ if (chsc_stzi(stp_page, &stzi, sizeof(stzi))) {
+ pr_err("stzi failed\n");
+ return;
+ }
+
+ timediff = tod_to_ns(lsoib->nlsout - get_tod_clock()) / NSEC_PER_SEC;
+ leapdiff = lsoib->nlso - lsoib->also;
+
+ if (leapdiff != 1 && leapdiff != -1) {
+ pr_err("Cannot schedule %d leap seconds\n", leapdiff);
+ return;
+ }
+
+ if (timediff < 0) {
+ if (stp_clear_leap() < 0)
+ pr_err("failed to clear leap second flags\n");
+ } else if (timediff < 7200) {
+ memset(&txc, 0, sizeof(txc));
+ ret = do_adjtimex(&txc);
+ if (ret < 0)
+ return;
+
+ txc.modes = ADJ_STATUS;
+ if (leapdiff > 0)
+ txc.status |= STA_INS;
+ else
+ txc.status |= STA_DEL;
+ ret = do_adjtimex(&txc);
+ if (ret < 0)
+ pr_err("failed to set leap second flags\n");
+ /* arm Timer to clear leap second flags */
+ mod_timer(&stp_timer, jiffies + msecs_to_jiffies(14400 * MSEC_PER_SEC));
+ } else {
+ /* The day the leap second is scheduled for hasn't been reached. Retry
+ * in one hour.
+ */
+ mod_timer(&stp_timer, jiffies + msecs_to_jiffies(3600 * MSEC_PER_SEC));
+ }
+}
+
/*
* STP work. Check for the STP state and take over the clock
* synchronization if the STP clock source is usable.
@@ -638,7 +682,7 @@ static void stp_work_fn(struct work_struct *work)
int rc;
/* prevent multiple execution. */
- mutex_lock(&stp_work_mutex);
+ mutex_lock(&stp_mutex);
if (!stp_online) {
chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000, NULL);
@@ -646,23 +690,22 @@ static void stp_work_fn(struct work_struct *work)
goto out_unlock;
}
- rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0, NULL);
+ rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xf0e0, NULL);
if (rc)
goto out_unlock;
- rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi));
+ rc = __store_stpinfo();
if (rc || stp_info.c == 0)
goto out_unlock;
/* Skip synchronization if the clock is already in sync. */
- if (check_sync_clock())
- goto out_unlock;
-
- memset(&stp_sync, 0, sizeof(stp_sync));
- cpus_read_lock();
- atomic_set(&stp_sync.cpus, num_online_cpus() - 1);
- stop_machine_cpuslocked(stp_sync_clock, &stp_sync, cpu_online_mask);
- cpus_read_unlock();
+ if (!check_sync_clock()) {
+ memset(&stp_sync, 0, sizeof(stp_sync));
+ cpus_read_lock();
+ atomic_set(&stp_sync.cpus, num_online_cpus() - 1);
+ stop_machine_cpuslocked(stp_sync_clock, &stp_sync, cpu_online_mask);
+ cpus_read_unlock();
+ }
if (!check_sync_clock())
/*
@@ -670,9 +713,11 @@ static void stp_work_fn(struct work_struct *work)
* Retry after a second.
*/
mod_timer(&stp_timer, jiffies + msecs_to_jiffies(MSEC_PER_SEC));
+ else if (stp_info.lu)
+ stp_check_leap();
out_unlock:
- mutex_unlock(&stp_work_mutex);
+ mutex_unlock(&stp_mutex);
}
/*
@@ -687,10 +732,14 @@ static ssize_t ctn_id_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online)
- return -ENODATA;
- return sprintf(buf, "%016llx\n",
- *(unsigned long long *) stp_info.ctnid);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid())
+ ret = sprintf(buf, "%016llx\n",
+ *(unsigned long long *) stp_info.ctnid);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(ctn_id);
@@ -699,9 +748,13 @@ static ssize_t ctn_type_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online)
- return -ENODATA;
- return sprintf(buf, "%i\n", stp_info.ctn);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid())
+ ret = sprintf(buf, "%i\n", stp_info.ctn);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(ctn_type);
@@ -710,9 +763,13 @@ static ssize_t dst_offset_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online || !(stp_info.vbits & 0x2000))
- return -ENODATA;
- return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid() && (stp_info.vbits & 0x2000))
+ ret = sprintf(buf, "%i\n", (int)(s16) stp_info.dsto);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(dst_offset);
@@ -721,20 +778,56 @@ static ssize_t leap_seconds_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online || !(stp_info.vbits & 0x8000))
- return -ENODATA;
- return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid() && (stp_info.vbits & 0x8000))
+ ret = sprintf(buf, "%i\n", (int)(s16) stp_info.leaps);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(leap_seconds);
+static ssize_t leap_seconds_scheduled_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct stp_stzi stzi;
+ ssize_t ret;
+
+ mutex_lock(&stp_mutex);
+ if (!stpinfo_valid() || !(stp_info.vbits & 0x8000) || !stp_info.lu) {
+ mutex_unlock(&stp_mutex);
+ return -ENODATA;
+ }
+
+ ret = chsc_stzi(stp_page, &stzi, sizeof(stzi));
+ mutex_unlock(&stp_mutex);
+ if (ret < 0)
+ return ret;
+
+ if (!stzi.lsoib.p)
+ return sprintf(buf, "0,0\n");
+
+ return sprintf(buf, "%llu,%d\n",
+ tod_to_ns(stzi.lsoib.nlsout - TOD_UNIX_EPOCH) / NSEC_PER_SEC,
+ stzi.lsoib.nlso - stzi.lsoib.also);
+}
+
+static DEVICE_ATTR_RO(leap_seconds_scheduled);
+
static ssize_t stratum_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online)
- return -ENODATA;
- return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid())
+ ret = sprintf(buf, "%i\n", (int)(s16) stp_info.stratum);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(stratum);
@@ -743,9 +836,13 @@ static ssize_t time_offset_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online || !(stp_info.vbits & 0x0800))
- return -ENODATA;
- return sprintf(buf, "%i\n", (int) stp_info.tto);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid() && (stp_info.vbits & 0x0800))
+ ret = sprintf(buf, "%i\n", (int) stp_info.tto);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(time_offset);
@@ -754,9 +851,13 @@ static ssize_t time_zone_offset_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online || !(stp_info.vbits & 0x4000))
- return -ENODATA;
- return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid() && (stp_info.vbits & 0x4000))
+ ret = sprintf(buf, "%i\n", (int)(s16) stp_info.tzo);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(time_zone_offset);
@@ -765,9 +866,13 @@ static ssize_t timing_mode_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online)
- return -ENODATA;
- return sprintf(buf, "%i\n", stp_info.tmd);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid())
+ ret = sprintf(buf, "%i\n", stp_info.tmd);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(timing_mode);
@@ -776,9 +881,13 @@ static ssize_t timing_state_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- if (!stp_online)
- return -ENODATA;
- return sprintf(buf, "%i\n", stp_info.tst);
+ ssize_t ret = -ENODATA;
+
+ mutex_lock(&stp_mutex);
+ if (stpinfo_valid())
+ ret = sprintf(buf, "%i\n", stp_info.tst);
+ mutex_unlock(&stp_mutex);
+ return ret;
}
static DEVICE_ATTR_RO(timing_state);
@@ -801,14 +910,14 @@ static ssize_t online_store(struct device *dev,
return -EINVAL;
if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags))
return -EOPNOTSUPP;
- mutex_lock(&clock_sync_mutex);
+ mutex_lock(&stp_mutex);
stp_online = value;
if (stp_online)
set_bit(CLOCK_SYNC_STP, &clock_sync_flags);
else
clear_bit(CLOCK_SYNC_STP, &clock_sync_flags);
queue_work(time_sync_wq, &stp_work);
- mutex_unlock(&clock_sync_mutex);
+ mutex_unlock(&stp_mutex);
return count;
}
@@ -824,6 +933,7 @@ static struct device_attribute *stp_attributes[] = {
&dev_attr_dst_offset,
&dev_attr_leap_seconds,
&dev_attr_online,
+ &dev_attr_leap_seconds_scheduled,
&dev_attr_stratum,
&dev_attr_time_offset,
&dev_attr_time_zone_offset,