From 677d762319facc20467243c6dd9487261e3515b0 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 20 Nov 2007 11:13:37 +0100 Subject: [S390] Dont overwrite lowcores on smp_send_stop(). Don't perform a sigp store-status-at-address on smp_send_stop(). It will overwrite the lowcores of other cpus and destroys valueable debug informations. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/smp.c | 56 +++++++------------------------------------------- 1 file changed, 7 insertions(+), 49 deletions(-) (limited to 'arch/s390/kernel') diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index b05ae858425..264ea906db4 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -193,71 +193,29 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, } EXPORT_SYMBOL(smp_call_function_single); -static void do_send_stop(void) +void smp_send_stop(void) { int cpu, rc; - /* stop all processors */ - for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) - continue; - do { - rc = signal_processor(cpu, sigp_stop); - } while (rc == sigp_busy); - } -} + /* Disable all interrupts/machine checks */ + __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); -static void do_store_status(void) -{ - int cpu, rc; + /* write magic number to zero page (absolute 0) */ + lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC; - /* store status of all processors in their lowcores (real 0) */ + /* stop all processors */ for_each_online_cpu(cpu) { if (cpu == smp_processor_id()) continue; do { - rc = signal_processor_p( - (__u32)(unsigned long) lowcore_ptr[cpu], cpu, - sigp_store_status_at_address); + rc = signal_processor(cpu, sigp_stop); } while (rc == sigp_busy); - } -} -static void do_wait_for_stop(void) -{ - int cpu; - - /* Wait for all other cpus to enter stopped state */ - for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) - continue; while (!smp_cpu_not_running(cpu)) cpu_relax(); } } -/* - * this function sends a 'stop' sigp to all other CPUs in the system. - * it goes straight through. - */ -void smp_send_stop(void) -{ - /* Disable all interrupts/machine checks */ - __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); - - /* write magic number to zero page (absolute 0) */ - lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC; - - /* stop other processors. */ - do_send_stop(); - - /* wait until other processors are stopped */ - do_wait_for_stop(); - - /* store status of other processors. */ - do_store_status(); -} - /* * Reboot, halt and power_off routines for SMP. */ -- cgit v1.2.3