s390/irq,idle: simplify idle check
Use the per-cpu CIF_ENABLED_WAIT flag to decide if an interrupt
occurred while a cpu was idle, instead of checking two conditions
within the old psw.
Also move clearing of the CIF_ENABLED_WAIT bit to the early interrupt
handler, which in turn makes arch_vcpu_is_preempted() also a bit more
precise, since the flag is now cleared before interrupt handlers have
been called.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
diff --git a/arch/s390/include/asm/idle.h b/arch/s390/include/asm/idle.h
index af72a2b..09f763b 100644
--- a/arch/s390/include/asm/idle.h
+++ b/arch/s390/include/asm/idle.h
@@ -23,6 +23,5 @@
extern struct device_attribute dev_attr_idle_time_us;
void psw_idle(struct s390_idle_data *data, unsigned long psw_mask);
-void psw_idle_exit(void);
#endif /* _S390_IDLE_H */
diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c
index dd8351e..1a1a419 100644
--- a/arch/s390/kernel/idle.c
+++ b/arch/s390/kernel/idle.c
@@ -28,7 +28,6 @@
u64 cycles_new[8];
int i;
- clear_cpu_flag(CIF_ENABLED_WAIT);
if (smp_cpu_mtid) {
stcctm(MT_DIAG, smp_cpu_mtid, cycles_new);
for (i = 0; i < smp_cpu_mtid; i++)
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 4539391..b020ff1 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -136,7 +136,7 @@
{
irqentry_state_t state = irqentry_enter(regs);
struct pt_regs *old_regs = set_irq_regs(regs);
- int from_idle;
+ bool from_idle;
irq_enter_rcu();
@@ -146,7 +146,7 @@
current->thread.last_break = regs->last_break;
}
- from_idle = !user_mode(regs) && regs->psw.addr == (unsigned long)psw_idle_exit;
+ from_idle = test_and_clear_cpu_flag(CIF_ENABLED_WAIT);
if (from_idle)
account_idle_time_irq();
@@ -171,7 +171,7 @@
{
irqentry_state_t state = irqentry_enter(regs);
struct pt_regs *old_regs = set_irq_regs(regs);
- int from_idle;
+ bool from_idle;
irq_enter_rcu();
@@ -185,7 +185,7 @@
regs->int_parm = S390_lowcore.ext_params;
regs->int_parm_long = S390_lowcore.ext_params2;
- from_idle = !user_mode(regs) && regs->psw.addr == (unsigned long)psw_idle_exit;
+ from_idle = test_and_clear_cpu_flag(CIF_ENABLED_WAIT);
if (from_idle)
account_idle_time_irq();
