diff options
| -rw-r--r-- | arch/s390/include/asm/cpu.h | 3 | ||||
| -rw-r--r-- | arch/s390/kernel/process.c | 67 | ||||
| -rw-r--r-- | arch/s390/kernel/smp.c | 25 | ||||
| -rw-r--r-- | arch/s390/kernel/vtime.c | 3 |
4 files changed, 61 insertions, 37 deletions
diff --git a/arch/s390/include/asm/cpu.h b/arch/s390/include/asm/cpu.h index e5a6a9ba3adf..89456df43c4a 100644 --- a/arch/s390/include/asm/cpu.h +++ b/arch/s390/include/asm/cpu.h @@ -14,7 +14,6 @@ struct s390_idle_data { spinlock_t lock; - unsigned int in_idle; unsigned long long idle_count; unsigned long long idle_enter; unsigned long long idle_time; @@ -26,7 +25,7 @@ void s390_idle_leave(void); static inline void s390_idle_check(void) { - if ((&__get_cpu_var(s390_idle))->in_idle) + if ((&__get_cpu_var(s390_idle))->idle_enter != 0ULL) s390_idle_leave(); } diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 04f8c67a6101..1e06436f07c2 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -38,6 +38,7 @@ #include <linux/utsname.h> #include <linux/tick.h> #include <linux/elfcore.h> +#include <linux/kernel_stat.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <asm/system.h> @@ -79,30 +80,19 @@ DEFINE_PER_CPU(struct s390_idle_data, s390_idle) = { .lock = __SPIN_LOCK_UNLOCKED(s390_idle.lock) }; -static int s390_idle_enter(void) +void s390_idle_leave(void) { struct s390_idle_data *idle; + unsigned long long idle_time; idle = &__get_cpu_var(s390_idle); + idle_time = S390_lowcore.int_clock - idle->idle_enter; spin_lock(&idle->lock); + idle->idle_time += idle_time; + idle->idle_enter = 0ULL; idle->idle_count++; - idle->in_idle = 1; - idle->idle_enter = get_clock(); spin_unlock(&idle->lock); - vtime_stop_cpu_timer(); - return NOTIFY_OK; -} - -void s390_idle_leave(void) -{ - struct s390_idle_data *idle; - vtime_start_cpu_timer(); - idle = &__get_cpu_var(s390_idle); - spin_lock(&idle->lock); - idle->idle_time += get_clock() - idle->idle_enter; - idle->in_idle = 0; - spin_unlock(&idle->lock); } extern void s390_handle_mcck(void); @@ -111,16 +101,16 @@ extern void s390_handle_mcck(void); */ static void default_idle(void) { + struct s390_idle_data *idle = &__get_cpu_var(s390_idle); + unsigned long addr; + psw_t psw; + /* CPU is going idle. */ local_irq_disable(); if (need_resched()) { local_irq_enable(); return; } - if (s390_idle_enter() == NOTIFY_BAD) { - local_irq_enable(); - return; - } #ifdef CONFIG_HOTPLUG_CPU if (cpu_is_offline(smp_processor_id())) { preempt_enable_no_resched(); @@ -138,9 +128,42 @@ static void default_idle(void) trace_hardirqs_on(); /* Don't trace preempt off for idle. */ stop_critical_timings(); + vtime_stop_cpu_timer(); + + /* + * The inline assembly is equivalent to + * idle->idle_enter = get_clock(); + * __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT | + * PSW_MASK_IO | PSW_MASK_EXT); + * The difference is that the inline assembly makes sure that + * the stck instruction is right before the lpsw instruction. + * This is done to increase the precision. + */ + /* Wait for external, I/O or machine check interrupt. */ - __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT | - PSW_MASK_IO | PSW_MASK_EXT); + psw.mask = psw_kernel_bits|PSW_MASK_WAIT|PSW_MASK_IO|PSW_MASK_EXT; +#ifndef __s390x__ + asm volatile( + " basr %0,0\n" + "0: ahi %0,1f-0b\n" + " st %0,4(%2)\n" + " stck 0(%3)\n" + " lpsw 0(%2)\n" + "1:" + : "=&d" (addr), "=m" (idle->idle_enter) + : "a" (&psw), "a" (&idle->idle_enter), "m" (psw) + : "memory", "cc"); +#else /* __s390x__ */ + asm volatile( + " larl %0,1f\n" + " stg %0,8(%2)\n" + " stck 0(%3)\n" + " lpswe 0(%2)\n" + "1:" + : "=&d" (addr), "=m" (idle->idle_enter) + : "a" (&psw), "a" (&idle->idle_enter), "m" (psw) + : "memory", "cc"); +#endif /* __s390x__ */ start_critical_timings(); } diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 6fc78541dc57..3979a6fc0882 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -851,9 +851,11 @@ static ssize_t show_idle_count(struct sys_device *dev, unsigned long long idle_count; idle = &per_cpu(s390_idle, dev->id); - spin_lock_irq(&idle->lock); + spin_lock(&idle->lock); idle_count = idle->idle_count; - spin_unlock_irq(&idle->lock); + if (idle->idle_enter) + idle_count++; + spin_unlock(&idle->lock); return sprintf(buf, "%llu\n", idle_count); } static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL); @@ -862,18 +864,17 @@ static ssize_t show_idle_time(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct s390_idle_data *idle; - unsigned long long new_time; + unsigned long long now, idle_time, idle_enter; idle = &per_cpu(s390_idle, dev->id); - spin_lock_irq(&idle->lock); - if (idle->in_idle) { - new_time = get_clock(); - idle->idle_time += new_time - idle->idle_enter; - idle->idle_enter = new_time; - } - new_time = idle->idle_time; - spin_unlock_irq(&idle->lock); - return sprintf(buf, "%llu\n", new_time >> 12); + spin_lock(&idle->lock); + now = get_clock(); + idle_time = idle->idle_time; + idle_enter = idle->idle_enter; + if (idle_enter != 0ULL && idle_enter < now) + idle_time += now - idle_enter; + spin_unlock(&idle->lock); + return sprintf(buf, "%llu\n", idle_time >> 12); } static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL); diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c index 1254a4d0d762..25d21fef76ba 100644 --- a/arch/s390/kernel/vtime.c +++ b/arch/s390/kernel/vtime.c @@ -112,6 +112,7 @@ EXPORT_SYMBOL_GPL(account_system_vtime); static inline void set_vtimer(__u64 expires) { + struct vtimer_queue *vq = &__get_cpu_var(virt_cpu_timer); __u64 timer; asm volatile (" STPT %0\n" /* Store current cpu timer value */ @@ -121,7 +122,7 @@ static inline void set_vtimer(__u64 expires) S390_lowcore.last_update_timer = expires; /* store expire time for this CPU timer */ - __get_cpu_var(virt_cpu_timer).to_expire = expires; + vq->to_expire = expires; } void vtime_start_cpu_timer(void) |
