diff options
| -rw-r--r-- | arch/s390/include/asm/processor.h | 3 | ||||
| -rw-r--r-- | arch/s390/kernel/processor.c | 17 | ||||
| -rw-r--r-- | arch/s390/kernel/smp.c | 2 | ||||
| -rw-r--r-- | include/linux/sched.h | 2 | ||||
| -rw-r--r-- | kernel/stop_machine.c | 14 |
5 files changed, 25 insertions, 13 deletions
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index b0fcbc37b637..445ce9ee4404 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -36,6 +36,7 @@ #ifndef __ASSEMBLY__ +#include <linux/cpumask.h> #include <linux/linkage.h> #include <linux/irqflags.h> #include <asm/cpu.h> @@ -225,7 +226,7 @@ static __no_kasan_or_inline unsigned short stap(void) * Give up the time slice of the virtual PU. */ #define cpu_relax_yield cpu_relax_yield -void cpu_relax_yield(void); +void cpu_relax_yield(const struct cpumask *cpumask); #define cpu_relax() barrier() 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); diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index f00955940694..44974654cbd0 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -414,7 +414,7 @@ void smp_yield_cpu(int cpu) diag_stat_inc_norecursion(DIAG_STAT_X09C); asm volatile("diag %0,0,0x9c" : : "d" (pcpu_devices[cpu].address)); - } else if (MACHINE_HAS_DIAG44) { + } else if (MACHINE_HAS_DIAG44 && !smp_cpu_mtid) { diag_stat_inc_norecursion(DIAG_STAT_X044); asm volatile("diag 0,0,0x44"); } diff --git a/include/linux/sched.h b/include/linux/sched.h index 11837410690f..1f9f3160da7e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1519,7 +1519,7 @@ static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpuma #endif #ifndef cpu_relax_yield -#define cpu_relax_yield() cpu_relax() +#define cpu_relax_yield(cpumask) cpu_relax() #endif extern int yield_to(struct task_struct *p, bool preempt); diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 2b5a6754646f..b8b0c5ff8da9 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -183,6 +183,7 @@ static int multi_cpu_stop(void *data) struct multi_stop_data *msdata = data; enum multi_stop_state curstate = MULTI_STOP_NONE; int cpu = smp_processor_id(), err = 0; + const struct cpumask *cpumask; unsigned long flags; bool is_active; @@ -192,15 +193,18 @@ static int multi_cpu_stop(void *data) */ local_save_flags(flags); - if (!msdata->active_cpus) - is_active = cpu == cpumask_first(cpu_online_mask); - else - is_active = cpumask_test_cpu(cpu, msdata->active_cpus); + if (!msdata->active_cpus) { + cpumask = cpu_online_mask; + is_active = cpu == cpumask_first(cpumask); + } else { + cpumask = msdata->active_cpus; + is_active = cpumask_test_cpu(cpu, cpumask); + } /* Simple state machine */ do { /* Chill out and ensure we re-read multi_stop_state. */ - cpu_relax_yield(); + cpu_relax_yield(cpumask); if (msdata->state != curstate) { curstate = msdata->state; switch (curstate) { |