s390/nohz: use a per-cpu flag for arch_needs_cpu

Move the nohz_delay bit from the s390_idle data structure to the
per-cpu flags. Clear the nohz delay flag in __cpu_disable and
remove the cpu hotplug notifier that used to do this.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky
2014-09-30 17:37:52 +02:00
parent a9b1649917
commit fe0f49768d
9 changed files with 11 additions and 31 deletions

View File

@@ -163,7 +163,7 @@ void __kprobes vtime_stop_cpu(void)
/* Wait for external, I/O or machine check interrupt. */
psw_mask = PSW_KERNEL_BITS | PSW_MASK_WAIT | PSW_MASK_DAT |
PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
idle->nohz_delay = 0;
clear_cpu_flag(CIF_NOHZ_DELAY);
/* Call the assembler magic in entry.S */
psw_idle(idle, psw_mask);
@@ -378,25 +378,8 @@ void init_cpu_vtimer(void)
set_vtimer(VTIMER_MAX_SLICE);
}
static int s390_nohz_notify(struct notifier_block *self, unsigned long action,
void *hcpu)
{
struct s390_idle_data *idle;
long cpu = (long) hcpu;
idle = &per_cpu(s390_idle, cpu);
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DYING:
idle->nohz_delay = 0;
default:
break;
}
return NOTIFY_OK;
}
void __init vtime_init(void)
{
/* Enable cpu timer interrupts on the boot cpu. */
init_cpu_vtimer();
cpu_notifier(s390_nohz_notify, 0);
}