5 files changed, 85 insertions, 96 deletions

diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h
index 133ce054fc89..521726430afa 100644
--- a/arch/s390/include/asm/cputime.h
+++ b/arch/s390/include/asm/cputime.h
@@ -11,7 +11,7 @@
 
 #include <asm/div64.h>
 
-/* We want to use micro-second resolution. */
+/* We want to use full resolution of the CPU timer: 2**-12 micro-seconds. */
 
 typedef unsigned long long cputime_t;
 typedef unsigned long long cputime64_t;
@@ -53,9 +53,9 @@ __div(unsigned long long n, unsigned int base)
 #define cputime_ge(__a, __b)            ((__a) >= (__b))
 #define cputime_lt(__a, __b)            ((__a) <  (__b))
 #define cputime_le(__a, __b)            ((__a) <= (__b))
-#define cputime_to_jiffies(__ct)        (__div((__ct), 1000000 / HZ))
+#define cputime_to_jiffies(__ct)        (__div((__ct), 4096000000ULL / HZ))
 #define cputime_to_scaled(__ct)         (__ct)
-#define jiffies_to_cputime(__hz)        ((cputime_t)(__hz) * (1000000 / HZ))
+#define jiffies_to_cputime(__hz)        ((cputime_t)(__hz) * (4096000000ULL / HZ))
 
 #define cputime64_zero                  (0ULL)
 #define cputime64_add(__a, __b)         ((__a) + (__b))
@@ -64,7 +64,7 @@ __div(unsigned long long n, unsigned int base)
 static inline u64
 cputime64_to_jiffies64(cputime64_t cputime)
 {
-        do_div(cputime, 1000000 / HZ);
+        do_div(cputime, 4096000000ULL / HZ);
         return cputime;
 }
 
@@ -74,13 +74,13 @@ cputime64_to_jiffies64(cputime64_t cputime)
 static inline unsigned int
 cputime_to_msecs(const cputime_t cputime)
 {
-        return __div(cputime, 1000);
+        return __div(cputime, 4096000);
 }
 
 static inline cputime_t
 msecs_to_cputime(const unsigned int m)
 {
-        return (cputime_t) m * 1000;
+        return (cputime_t) m * 4096000;
 }
 
 /*
@@ -89,13 +89,13 @@ msecs_to_cputime(const unsigned int m)
 static inline unsigned int
 cputime_to_secs(const cputime_t cputime)
 {
-        return __div(cputime, 1000000);
+        return __div(cputime, 2048000000) >> 1;
 }
 
 static inline cputime_t
 secs_to_cputime(const unsigned int s)
 {
-        return (cputime_t) s * 1000000;
+        return (cputime_t) s * 4096000000ULL;
 }
 
 /*
@@ -104,7 +104,7 @@ secs_to_cputime(const unsigned int s)
 static inline cputime_t
 timespec_to_cputime(const struct timespec *value)
 {
-        return value->tv_nsec / 1000 + (u64) value->tv_sec * 1000000;
+        return value->tv_nsec * 4096 / 1000 + (u64) value->tv_sec * 4096000000ULL;
 }
 
 static inline void
@@ -114,12 +114,12 @@ cputime_to_timespec(const cputime_t cputime, struct timespec *value)
         register_pair rp;
 
         rp.pair = cputime >> 1;
-        asm ("dr %0,%1" : "+d" (rp) : "d" (1000000 >> 1));
-        value->tv_nsec = rp.subreg.even * 1000;
+        asm ("dr %0,%1" : "+d" (rp) : "d" (2048000000UL));
+        value->tv_nsec = rp.subreg.even * 1000 / 4096;
         value->tv_sec = rp.subreg.odd;
 #else
-        value->tv_nsec = (cputime % 1000000) * 1000;
-        value->tv_sec = cputime / 1000000;
+        value->tv_nsec = (cputime % 4096000000ULL) * 1000 / 4096;
+        value->tv_sec = cputime / 4096000000ULL;
 #endif
 }
 
@@ -131,7 +131,7 @@ cputime_to_timespec(const cputime_t cputime, struct timespec *value)
 static inline cputime_t
 timeval_to_cputime(const struct timeval *value)
 {
-        return value->tv_usec + (u64) value->tv_sec * 1000000;
+        return value->tv_usec * 4096 + (u64) value->tv_sec * 4096000000ULL;
 }
 
 static inline void
@@ -141,12 +141,12 @@ cputime_to_timeval(const cputime_t cputime, struct timeval *value)
         register_pair rp;
 
         rp.pair = cputime >> 1;
-        asm ("dr %0,%1" : "+d" (rp) : "d" (1000000 >> 1));
-        value->tv_usec = rp.subreg.even;
+        asm ("dr %0,%1" : "+d" (rp) : "d" (2048000000UL));
+        value->tv_usec = rp.subreg.even / 4096;
         value->tv_sec = rp.subreg.odd;
 #else
-        value->tv_usec = cputime % 1000000;
-        value->tv_sec = cputime / 1000000;
+        value->tv_usec = cputime % 4096000000ULL;
+        value->tv_sec = cputime / 4096000000ULL;
 #endif
 }
 
@@ -156,13 +156,13 @@ cputime_to_timeval(const cputime_t cputime, struct timeval *value)
 static inline clock_t
 cputime_to_clock_t(cputime_t cputime)
 {
-        return __div(cputime, 1000000 / USER_HZ);
+        return __div(cputime, 4096000000ULL / USER_HZ);
 }
 
 static inline cputime_t
 clock_t_to_cputime(unsigned long x)
 {
-        return (cputime_t) x * (1000000 / USER_HZ);
+        return (cputime_t) x * (4096000000ULL / USER_HZ);
 }
 
 /*
@@ -171,7 +171,7 @@ clock_t_to_cputime(unsigned long x)
 static inline clock_t
 cputime64_to_clock_t(cputime64_t cputime)
 {
-       return __div(cputime, 1000000 / USER_HZ);
+       return __div(cputime, 4096000000ULL / USER_HZ);
 }
 
 #endif /* _S390_CPUTIME_H */
diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index 0bc51d52a899..a547817cf1ab 100644
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -67,11 +67,11 @@
 #define __LC_SYNC_ENTER_TIMER           0x248
 #define __LC_ASYNC_ENTER_TIMER          0x250
 #define __LC_EXIT_TIMER                 0x258
-#define __LC_LAST_UPDATE_TIMER          0x260
-#define __LC_USER_TIMER                 0x268
-#define __LC_SYSTEM_TIMER               0x270
-#define __LC_LAST_UPDATE_CLOCK          0x278
-#define __LC_STEAL_CLOCK                0x280
+#define __LC_USER_TIMER                 0x260
+#define __LC_SYSTEM_TIMER               0x268
+#define __LC_STEAL_TIMER                0x270
+#define __LC_LAST_UPDATE_TIMER          0x278
+#define __LC_LAST_UPDATE_CLOCK          0x280
 #define __LC_RETURN_MCCK_PSW            0x288
 #define __LC_KERNEL_STACK               0xC40
 #define __LC_THREAD_INFO                0xC44
@@ -89,11 +89,11 @@
 #define __LC_SYNC_ENTER_TIMER           0x250
 #define __LC_ASYNC_ENTER_TIMER          0x258
 #define __LC_EXIT_TIMER                 0x260
-#define __LC_LAST_UPDATE_TIMER          0x268
-#define __LC_USER_TIMER                 0x270
-#define __LC_SYSTEM_TIMER               0x278
-#define __LC_LAST_UPDATE_CLOCK          0x280
-#define __LC_STEAL_CLOCK                0x288
+#define __LC_USER_TIMER                 0x268
+#define __LC_SYSTEM_TIMER               0x270
+#define __LC_STEAL_TIMER                0x278
+#define __LC_LAST_UPDATE_TIMER          0x280
+#define __LC_LAST_UPDATE_CLOCK          0x288
 #define __LC_RETURN_MCCK_PSW            0x290
 #define __LC_KERNEL_STACK               0xD40
 #define __LC_THREAD_INFO                0xD48
@@ -252,11 +252,11 @@ struct _lowcore
         __u64        sync_enter_timer;         /* 0x248 */
         __u64        async_enter_timer;        /* 0x250 */
         __u64        exit_timer;               /* 0x258 */
-        __u64        last_update_timer;        /* 0x260 */
-        __u64        user_timer;               /* 0x268 */
-        __u64        system_timer;             /* 0x270 */
-        __u64        last_update_clock;        /* 0x278 */
-        __u64        steal_clock;              /* 0x280 */
+        __u64        user_timer;               /* 0x260 */
+        __u64        system_timer;             /* 0x268 */
+        __u64        steal_timer;              /* 0x270 */
+        __u64        last_update_timer;        /* 0x278 */
+        __u64        last_update_clock;        /* 0x280 */
         psw_t        return_mcck_psw;          /* 0x288 */
         __u8         pad8[0xc00-0x290];        /* 0x290 */
 
@@ -343,11 +343,11 @@ struct _lowcore
         __u64        sync_enter_timer;         /* 0x250 */
         __u64        async_enter_timer;        /* 0x258 */
         __u64        exit_timer;               /* 0x260 */
-        __u64        last_update_timer;        /* 0x268 */
-        __u64        user_timer;               /* 0x270 */
-        __u64        system_timer;             /* 0x278 */
-        __u64        last_update_clock;        /* 0x280 */
-        __u64        steal_clock;              /* 0x288 */
+        __u64        user_timer;               /* 0x268 */
+        __u64        system_timer;             /* 0x270 */
+        __u64        steal_timer;              /* 0x278 */
+        __u64        last_update_timer;        /* 0x280 */
+        __u64        last_update_clock;        /* 0x288 */
         psw_t        return_mcck_psw;          /* 0x290 */
         __u8         pad8[0xc00-0x2a0];        /* 0x2a0 */
         /* System info area */
diff --git a/arch/s390/include/asm/system.h b/arch/s390/include/asm/system.h
index 024ef42ed6d7..3a8b26eb1f2e 100644
--- a/arch/s390/include/asm/system.h
+++ b/arch/s390/include/asm/system.h
@@ -99,7 +99,7 @@ static inline void restore_access_regs(unsigned int *acrs)
         prev = __switch_to(prev,next);                                       \
 } while (0)
 
-extern void account_vtime(struct task_struct *);
+extern void account_vtime(struct task_struct *, struct task_struct *);
 extern void account_tick_vtime(struct task_struct *);
 extern void account_system_vtime(struct task_struct *);
 
@@ -121,7 +121,7 @@ static inline void cmma_init(void) { }
 
 #define finish_arch_switch(prev) do {                                        \
         set_fs(current->thread.mm_segment);                                  \
-        account_vtime(prev);                                                 \
+        account_vtime(prev, current);                                        \
 } while (0)
 
 #define nop() asm volatile("nop")
diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h
index c1eaf9604da7..c544aa524535 100644
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -47,6 +47,8 @@ struct thread_info {
         unsigned int            cpu;            /* current CPU */
         int                     preempt_count;  /* 0 => preemptable, <0 => BUG */
         struct restart_block    restart_block;
+        __u64                   user_timer;
+        __u64                   system_timer;
 };
 
 /*
diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index 4a4a34caec55..1254a4d0d762 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -31,11 +31,10 @@ static DEFINE_PER_CPU(struct vtimer_queue, virt_cpu_timer);
  * Update process times based on virtual cpu times stored by entry.S
  * to the lowcore fields user_timer, system_timer & steal_clock.
  */
-void account_process_tick(struct task_struct *tsk, int user_tick)
+static void do_account_vtime(struct task_struct *tsk, int hardirq_offset)
 {
-        cputime_t cputime;
-        __u64 timer, clock;
-        int rcu_user_flag;
+        struct thread_info *ti = task_thread_info(tsk);
+        __u64 timer, clock, user, system, steal;
 
         timer = S390_lowcore.last_update_timer;
         clock = S390_lowcore.last_update_clock;
@@ -44,59 +43,47 @@ void account_process_tick(struct task_struct *tsk, int user_tick)
                       : "=m" (S390_lowcore.last_update_timer),
                         "=m" (S390_lowcore.last_update_clock) );
         S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer;
-        S390_lowcore.steal_clock += S390_lowcore.last_update_clock - clock;
+        S390_lowcore.steal_timer += S390_lowcore.last_update_clock - clock;
 
-        cputime = S390_lowcore.user_timer >> 12;
-        rcu_user_flag = cputime != 0;
-        S390_lowcore.user_timer -= cputime << 12;
-        S390_lowcore.steal_clock -= cputime << 12;
-        account_user_time(tsk, cputime, cputime);
+        user = S390_lowcore.user_timer - ti->user_timer;
+        S390_lowcore.steal_timer -= user;
+        ti->user_timer = S390_lowcore.user_timer;
+        account_user_time(tsk, user, user);
 
-        cputime =  S390_lowcore.system_timer >> 12;
-        S390_lowcore.system_timer -= cputime << 12;
-        S390_lowcore.steal_clock -= cputime << 12;
+        system = S390_lowcore.system_timer - ti->system_timer;
+        S390_lowcore.steal_timer -= system;
+        ti->system_timer = S390_lowcore.system_timer;
         if (idle_task(smp_processor_id()) != current)
-                account_system_time(tsk, HARDIRQ_OFFSET, cputime, cputime);
+                account_system_time(tsk, hardirq_offset, system, system);
         else
-                account_idle_time(cputime);
+                account_idle_time(system);
 
-        cputime = S390_lowcore.steal_clock;
-        if ((__s64) cputime > 0) {
-                cputime >>= 12;
-                S390_lowcore.steal_clock -= cputime << 12;
+        steal = S390_lowcore.steal_timer;
+        if ((s64) steal > 0) {
+                S390_lowcore.steal_timer = 0;
                 if (idle_task(smp_processor_id()) != current)
-                        account_steal_time(cputime);
+                        account_steal_time(steal);
                 else
-                        account_idle_time(cputime);
+                        account_idle_time(steal);
         }
 }
 
-/*
- * Update process times based on virtual cpu times stored by entry.S
- * to the lowcore fields user_timer, system_timer & steal_clock.
- */
-void account_vtime(struct task_struct *tsk)
+void account_vtime(struct task_struct *prev, struct task_struct *next)
 {
-        cputime_t cputime;
-        __u64 timer;
-
-        timer = S390_lowcore.last_update_timer;
-        asm volatile ("  STPT %0"    /* Store current cpu timer value */
-                      : "=m" (S390_lowcore.last_update_timer) );
-        S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer;
-
-        cputime = S390_lowcore.user_timer >> 12;
-        S390_lowcore.user_timer -= cputime << 12;
-        S390_lowcore.steal_clock -= cputime << 12;
-        account_user_time(tsk, cputime, cputime);
+        struct thread_info *ti;
+
+        do_account_vtime(prev, 0);
+        ti = task_thread_info(prev);
+        ti->user_timer = S390_lowcore.user_timer;
+        ti->system_timer = S390_lowcore.system_timer;
+        ti = task_thread_info(next);
+        S390_lowcore.user_timer = ti->user_timer;
+        S390_lowcore.system_timer = ti->system_timer;
+}
 
-        cputime =  S390_lowcore.system_timer >> 12;
-        S390_lowcore.system_timer -= cputime << 12;
-        S390_lowcore.steal_clock -= cputime << 12;
-        if (idle_task(smp_processor_id()) != current)
-                account_system_time(tsk, 0, cputime, cputime);
-        else
-                account_idle_time(cputime);
+void account_process_tick(struct task_struct *tsk, int user_tick)
+{
+        do_account_vtime(tsk, HARDIRQ_OFFSET);
 }
 
 /*
@@ -105,21 +92,21 @@ void account_vtime(struct task_struct *tsk)
  */
 void account_system_vtime(struct task_struct *tsk)
 {
-        cputime_t cputime;
-        __u64 timer;
+        struct thread_info *ti = task_thread_info(tsk);
+        __u64 timer, system;
 
         timer = S390_lowcore.last_update_timer;
         asm volatile ("  STPT %0"    /* Store current cpu timer value */
                       : "=m" (S390_lowcore.last_update_timer) );
         S390_lowcore.system_timer += timer - S390_lowcore.last_update_timer;
 
-        cputime =  S390_lowcore.system_timer >> 12;
-        S390_lowcore.system_timer -= cputime << 12;
-        S390_lowcore.steal_clock -= cputime << 12;
+        system = S390_lowcore.system_timer - ti->system_timer;
+        S390_lowcore.steal_timer -= system;
+        ti->system_timer = S390_lowcore.system_timer;
         if (in_irq() || idle_task(smp_processor_id()) != current)
-                account_system_time(tsk, 0, cputime, cputime);
+                account_system_time(tsk, 0, system, system);
         else
-                account_idle_time(cputime);
+                account_idle_time(system);
 }
 EXPORT_SYMBOL_GPL(account_system_vtime);
 
@@ -490,8 +477,8 @@ void init_cpu_vtimer(void)
         /* kick the virtual timer */
         S390_lowcore.exit_timer = VTIMER_MAX_SLICE;
         S390_lowcore.last_update_timer = VTIMER_MAX_SLICE;
-        asm volatile ("SPT %0" : : "m" (S390_lowcore.last_update_timer));
         asm volatile ("STCK %0" : "=m" (S390_lowcore.last_update_clock));
+        asm volatile ("SPT %0" : : "m" (S390_lowcore.last_update_timer));
 
         /* enable cpu timer interrupts */
         __ctl_set_bit(0,10);