[PATCH v4 1/3] xen: move wallclock functions from x86 to common

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

Remove dummy arm implementation of wallclock_time.
Use shared_info() in common code rather than x86-ism to access it, when
possible.

Define the static variable wc_sec, and the local variale sec in
update_domain_wallclock_time, as uint64_t instead of unsigned long, to
avoid size issue on arm.
Take a uint64_t sec paramter in do_settime for the same reason.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
CC: JBeulich@suse.com
CC: andrew.cooper3@citrix.com

---

Changes in v3:
- remove stray blank lines

Changes in v2:
- remove stray blank lines
- remove include <xen/config.h>
- move version_update_* to include/xen/time.h
- introduce ifdef to fix build issue in common/time.c
- define wc_sec and sec as uint64_t
- pass u64 to do_settime
---
 xen/arch/arm/time.c    |    5 ---
 xen/arch/x86/time.c    |   96 +-----------------------------------------------
 xen/common/time.c      |   95 ++++++++++++++++++++++++++++++++++++++++++++++-
 xen/include/xen/time.h |    5 ++-
 4 files changed, 99 insertions(+), 102 deletions(-)

diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
index 5ded30c..6207615 100644
--- a/xen/arch/arm/time.c
+++ b/xen/arch/arm/time.c
@@ -280,11 +280,6 @@ void domain_set_time_offset(struct domain *d, int64_t time_offset_seconds)
     /* XXX update guest visible wallclock time */
 }
 
-struct tm wallclock_time(uint64_t *ns)
-{
-    return (struct tm) { 0 };
-}
-
 /*
  * Local variables:
  * mode: C
diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index bbb7e6c..0f16db5 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -47,9 +47,6 @@ string_param("clocksource", opt_clocksource);
 unsigned long __read_mostly cpu_khz;  /* CPU clock frequency in kHz. */
 DEFINE_SPINLOCK(rtc_lock);
 unsigned long pit0_ticks;
-static unsigned long wc_sec; /* UTC time at last 'time update'. */
-static unsigned int wc_nsec;
-static DEFINE_SPINLOCK(wc_lock);
 
 struct cpu_time {
     u64 local_tsc_stamp;
@@ -783,10 +780,6 @@ uint64_t tsc_ticks2ns(uint64_t ticks)
     return scale_delta(ticks, &t->tsc_scale);
 }
 
-/* Explicitly OR with 1 just in case version number gets out of sync. */
-#define version_update_begin(v) (((v)+1)|1)
-#define version_update_end(v)   ((v)+1)
-
 static void __update_vcpu_system_time(struct vcpu *v, int force)
 {
     struct cpu_time       *t;
@@ -900,37 +893,6 @@ void force_update_vcpu_system_time(struct vcpu *v)
     __update_vcpu_system_time(v, 1);
 }
 
-void update_domain_wallclock_time(struct domain *d)
-{
-    uint32_t *wc_version;
-    unsigned long sec;
-
-    spin_lock(&wc_lock);
-
-    wc_version = &shared_info(d, wc_version);
-    *wc_version = version_update_begin(*wc_version);
-    wmb();
-
-    sec = wc_sec + d->time_offset_seconds;
-    if ( likely(!has_32bit_shinfo(d)) )
-    {
-        d->shared_info->native.wc_sec    = sec;
-        d->shared_info->native.wc_nsec   = wc_nsec;
-        d->shared_info->native.wc_sec_hi = sec >> 32;
-    }
-    else
-    {
-        d->shared_info->compat.wc_sec         = sec;
-        d->shared_info->compat.wc_nsec        = wc_nsec;
-        d->shared_info->compat.arch.wc_sec_hi = sec >> 32;
-    }
-
-    wmb();
-    *wc_version = version_update_end(*wc_version);
-
-    spin_unlock(&wc_lock);
-}
-
 static void update_domain_rtc(void)
 {
     struct domain *d;
@@ -988,27 +950,6 @@ int cpu_frequency_change(u64 freq)
     return 0;
 }
 
-/* Set clock to <secs,usecs> after 00:00:00 UTC, 1 January, 1970. */
-void do_settime(unsigned long secs, unsigned int nsecs, u64 system_time_base)
-{
-    u64 x;
-    u32 y;
-    struct domain *d;
-
-    x = SECONDS(secs) + nsecs - system_time_base;
-    y = do_div(x, 1000000000);
-
-    spin_lock(&wc_lock);
-    wc_sec  = x;
-    wc_nsec = y;
-    spin_unlock(&wc_lock);
-
-    rcu_read_lock(&domlist_read_lock);
-    for_each_domain ( d )
-        update_domain_wallclock_time(d);
-    rcu_read_unlock(&domlist_read_lock);
-}
-
 /* Per-CPU communication between rendezvous IRQ and softirq handler. */
 struct cpu_calibration {
     u64 local_tsc_stamp;
@@ -1608,25 +1549,6 @@ void send_timer_event(struct vcpu *v)
     send_guest_vcpu_virq(v, VIRQ_TIMER);
 }
 
-/* Return secs after 00:00:00 localtime, 1 January, 1970. */
-unsigned long get_localtime(struct domain *d)
-{
-    return wc_sec + (wc_nsec + NOW()) / 1000000000ULL 
-        + d->time_offset_seconds;
-}
-
-/* Return microsecs after 00:00:00 localtime, 1 January, 1970. */
-uint64_t get_localtime_us(struct domain *d)
-{
-    return (SECONDS(wc_sec + d->time_offset_seconds) + wc_nsec + NOW())
-           / 1000UL;
-}
-
-unsigned long get_sec(void)
-{
-    return wc_sec + (wc_nsec + NOW()) / 1000000000ULL;
-}
-
 /* "cmos_utc_offset" is the difference between UTC time and CMOS time. */
 static long cmos_utc_offset; /* in seconds */
 
@@ -1635,7 +1557,7 @@ int time_suspend(void)
     if ( smp_processor_id() == 0 )
     {
         cmos_utc_offset = -get_cmos_time();
-        cmos_utc_offset += (wc_sec + (wc_nsec + NOW()) / 1000000000ULL);
+        cmos_utc_offset += get_sec();
         kill_timer(&calibration_timer);
 
         /* Sync platform timer stamps. */
@@ -1715,22 +1637,6 @@ int hwdom_pit_access(struct ioreq *ioreq)
     return 0;
 }
 
-struct tm wallclock_time(uint64_t *ns)
-{
-    uint64_t seconds, nsec;
-
-    if ( !wc_sec )
-        return (struct tm) { 0 };
-
-    seconds = NOW() + SECONDS(wc_sec) + wc_nsec;
-    nsec = do_div(seconds, 1000000000);
-
-    if ( ns )
-        *ns = nsec;
-
-    return gmtime(seconds);
-}
-
 /*
  * PV SoftTSC Emulation.
  */
diff --git a/xen/common/time.c b/xen/common/time.c
index 29fdf52..721ada8 100644
--- a/xen/common/time.c
+++ b/xen/common/time.c
@@ -15,8 +15,12 @@
  * along with this program; If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <xen/config.h>
+#include <xen/sched.h>
+#include <xen/shared.h>
+#include <xen/spinlock.h>
 #include <xen/time.h>
+#include <asm/div64.h>
+#include <asm/domain.h>
 
 /* Nonzero if YEAR is a leap year (every 4 years,
    except every 100th isn't, and every 400th is).  */
@@ -34,6 +38,10 @@ const unsigned short int __mon_lengths[2][12] = {
 #define SECS_PER_HOUR (60 * 60)
 #define SECS_PER_DAY  (SECS_PER_HOUR * 24)
 
+static uint64_t wc_sec; /* UTC time at last 'time update'. */
+static unsigned int wc_nsec;
+static DEFINE_SPINLOCK(wc_lock);
+
 struct tm gmtime(unsigned long t)
 {
     struct tm tbuf;
@@ -85,3 +93,88 @@ struct tm gmtime(unsigned long t)
 
     return tbuf;
 }
+
+void update_domain_wallclock_time(struct domain *d)
+{
+    uint32_t *wc_version;
+    uint64_t sec;
+
+    spin_lock(&wc_lock);
+
+    wc_version = &shared_info(d, wc_version);
+    *wc_version = version_update_begin(*wc_version);
+    wmb();
+
+    sec = wc_sec + d->time_offset_seconds;
+    shared_info(d, wc_sec)    = sec;
+    shared_info(d, wc_nsec)   = wc_nsec;
+#ifdef CONFIG_X86
+    if ( likely(!has_32bit_shinfo(d)) )
+        d->shared_info->native.wc_sec_hi = sec >> 32;
+    else
+        d->shared_info->compat.arch.wc_sec_hi = sec >> 32;
+#else
+    shared_info(d, wc_sec_hi) = sec >> 32;
+#endif
+
+    wmb();
+    *wc_version = version_update_end(*wc_version);
+
+    spin_unlock(&wc_lock);
+}
+
+/* Set clock to <secs,usecs> after 00:00:00 UTC, 1 January, 1970. */
+void do_settime(u64 secs, unsigned int nsecs, u64 system_time_base)
+{
+    u64 x;
+    u32 y;
+    struct domain *d;
+
+    x = SECONDS(secs) + nsecs - system_time_base;
+    y = do_div(x, 1000000000);
+
+    spin_lock(&wc_lock);
+    wc_sec  = x;
+    wc_nsec = y;
+    spin_unlock(&wc_lock);
+
+    rcu_read_lock(&domlist_read_lock);
+    for_each_domain ( d )
+        update_domain_wallclock_time(d);
+    rcu_read_unlock(&domlist_read_lock);
+}
+
+/* Return secs after 00:00:00 localtime, 1 January, 1970. */
+unsigned long get_localtime(struct domain *d)
+{
+    return wc_sec + (wc_nsec + NOW()) / 1000000000ULL
+        + d->time_offset_seconds;
+}
+
+/* Return microsecs after 00:00:00 localtime, 1 January, 1970. */
+uint64_t get_localtime_us(struct domain *d)
+{
+    return (SECONDS(wc_sec + d->time_offset_seconds) + wc_nsec + NOW())
+           / 1000UL;
+}
+
+unsigned long get_sec(void)
+{
+    return wc_sec + (wc_nsec + NOW()) / 1000000000ULL;
+}
+
+struct tm wallclock_time(uint64_t *ns)
+{
+    uint64_t seconds, nsec;
+
+    if ( !wc_sec )
+        return (struct tm) { 0 };
+
+    seconds = NOW() + SECONDS(wc_sec) + wc_nsec;
+    nsec = do_div(seconds, 1000000000);
+
+    if ( ns )
+        *ns = nsec;
+
+    return gmtime(seconds);
+}
diff --git a/xen/include/xen/time.h b/xen/include/xen/time.h
index da4e8d7..b742746 100644
--- a/xen/include/xen/time.h
+++ b/xen/include/xen/time.h
@@ -60,11 +60,14 @@ struct tm wallclock_time(uint64_t *ns);
 /* Chosen so (NOW() + delta) wont overflow without an uptime of 200 years */
 #define STIME_DELTA_MAX ((s_time_t)((uint64_t)~0ull>>2))
 
+/* Explicitly OR with 1 just in case version number gets out of sync. */
+#define version_update_begin(v) (((v) + 1) | 1)
+#define version_update_end(v)   ((v) + 1)
 extern void update_vcpu_system_time(struct vcpu *v);
 extern void update_domain_wallclock_time(struct domain *d);
 
 extern void do_settime(
-    unsigned long secs, unsigned int nsecs, u64 system_time_base);
+    u64 secs, unsigned int nsecs, u64 system_time_base);
 
 extern void send_timer_event(struct vcpu *v);
 
-- 
1.7.10.4