diff options
Diffstat (limited to 'arch/s390/kernel/smp.c')
| -rw-r--r-- | arch/s390/kernel/smp.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 6ab16ac64d2..e4572601e91 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -97,6 +97,29 @@ static inline int cpu_stopped(int cpu) return raw_cpu_stopped(cpu_logical_map(cpu)); } +/* + * Ensure that PSW restart is done on an online CPU + */ +void smp_restart_with_online_cpu(void) +{ + int cpu; + + for_each_online_cpu(cpu) { + if (stap() == __cpu_logical_map[cpu]) { + /* We are online: Enable DAT again and return */ + __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); + return; + } + } + /* We are not online: Do PSW restart on an online CPU */ + while (sigp(cpu, sigp_restart) == sigp_busy) + cpu_relax(); + /* And stop ourself */ + while (raw_sigp(stap(), sigp_stop) == sigp_busy) + cpu_relax(); + for (;;); +} + void smp_switch_to_ipl_cpu(void (*func)(void *), void *data) { struct _lowcore *lc, *current_lc; |