diff options
Diffstat (limited to 'arch/s390/lib/delay.c')
| -rw-r--r-- | arch/s390/lib/delay.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c index daca7bad66de..68d61f2835df 100644 --- a/arch/s390/lib/delay.c +++ b/arch/s390/lib/delay.c @@ -13,11 +13,19 @@ #include <linux/export.h> #include <linux/irqflags.h> #include <linux/interrupt.h> +#include <linux/jump_label.h> #include <linux/irq.h> #include <asm/vtimer.h> #include <asm/div64.h> #include <asm/idle.h> +static DEFINE_STATIC_KEY_FALSE(udelay_ready); + +void __init udelay_enable(void) +{ + static_branch_enable(&udelay_ready); +} + void __delay(unsigned long loops) { /* @@ -33,7 +41,7 @@ EXPORT_SYMBOL(__delay); static void __udelay_disabled(unsigned long long usecs) { - unsigned long cr0, cr0_new, psw_mask, flags; + unsigned long cr0, cr0_new, psw_mask; struct s390_idle_data idle; u64 end; @@ -45,9 +53,8 @@ static void __udelay_disabled(unsigned long long usecs) psw_mask = __extract_psw() | PSW_MASK_EXT | PSW_MASK_WAIT; set_clock_comparator(end); set_cpu_flag(CIF_IGNORE_IRQ); - local_irq_save(flags); psw_idle(&idle, psw_mask); - local_irq_restore(flags); + trace_hardirqs_off(); clear_cpu_flag(CIF_IGNORE_IRQ); set_clock_comparator(S390_lowcore.clock_comparator); __ctl_load(cr0, 0, 0); @@ -77,6 +84,11 @@ void __udelay(unsigned long long usecs) { unsigned long flags; + if (!static_branch_likely(&udelay_ready)) { + udelay_simple(usecs); + return; + } + preempt_disable(); local_irq_save(flags); if (in_irq()) { |