diff options
Diffstat (limited to 'arch/s390/kernel/processor.c')
| -rw-r--r-- | arch/s390/kernel/processor.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c index 5de13307b703..4cdaefec1b7c 100644 --- a/arch/s390/kernel/processor.c +++ b/arch/s390/kernel/processor.c @@ -31,6 +31,7 @@ struct cpu_info { }; static DEFINE_PER_CPU(struct cpu_info, cpu_info); +static DEFINE_PER_CPU(int, cpu_relax_retry); static bool machine_has_cpu_mhz; @@ -58,13 +59,19 @@ void s390_update_cpu_mhz(void) on_each_cpu(update_cpu_mhz, NULL, 0); } -void notrace cpu_relax_yield(void) +void notrace cpu_relax_yield(const struct cpumask *cpumask) { - if (!smp_cpu_mtid && MACHINE_HAS_DIAG44) { - diag_stat_inc(DIAG_STAT_X044); - asm volatile("diag 0,0,0x44"); + int cpu, this_cpu; + + this_cpu = smp_processor_id(); + if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) { + __this_cpu_write(cpu_relax_retry, 0); + cpu = cpumask_next_wrap(this_cpu, cpumask, this_cpu, false); + if (cpu >= nr_cpu_ids) + return; + if (arch_vcpu_is_preempted(cpu)) + smp_yield_cpu(cpu); } - barrier(); } EXPORT_SYMBOL(cpu_relax_yield); |