From c6b5b847a7cf11f131c43fe0041443ec11697fc7 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 4 Dec 2006 15:40:33 +0100 Subject: [PATCH] [S390] cpu shutdown rework Let one master cpu kill all other cpus instead of sending an external interrupt to all other cpus so they can kill themselves. Simplifies reipl/shutdown functions a lot. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/ipl.c | 24 +------ arch/s390/kernel/machine_kexec.c | 65 +++++-------------- arch/s390/kernel/smp.c | 104 +++++++++---------------------- drivers/s390/char/sclp_quiesce.c | 37 +---------- include/asm-s390/smp.h | 8 +++ 5 files changed, 58 insertions(+), 180 deletions(-) diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c index 101b003cfabf..a36bea1188d9 100644 --- a/arch/s390/kernel/ipl.c +++ b/arch/s390/kernel/ipl.c @@ -576,23 +576,6 @@ static struct subsys_attribute dump_type_attr = static decl_subsys(dump, NULL, NULL); -#ifdef CONFIG_SMP -static void dump_smp_stop_all(void) -{ - int cpu; - preempt_disable(); - for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) - continue; - while (signal_processor(cpu, sigp_stop) == sigp_busy) - udelay(10); - } - preempt_enable(); -} -#else -#define dump_smp_stop_all() do { } while (0) -#endif - /* * Shutdown actions section */ @@ -724,13 +707,13 @@ static void do_dump(void) switch (dump_method) { case IPL_METHOD_CCW_CIO: - dump_smp_stop_all(); + smp_send_stop(); devid.devno = dump_block_ccw->ipl_info.ccw.devno; devid.ssid = 0; reipl_ccw_dev(&devid); break; case IPL_METHOD_CCW_VM: - dump_smp_stop_all(); + smp_send_stop(); sprintf(buf, "STORE STATUS"); __cpcmd(buf, NULL, 0, NULL); sprintf(buf, "IPL %X", dump_block_ccw->ipl_info.ccw.devno); @@ -1059,9 +1042,6 @@ void s390_reset_system(void) { struct _lowcore *lc; - /* Disable all interrupts/machine checks */ - __load_psw_mask(PSW_KERNEL_BITS & ~PSW_MASK_MCHECK); - /* Stack for interrupt/machine check handler */ lc = (struct _lowcore *)(unsigned long) store_prefix(); lc->panic_stack = S390_lowcore.panic_stack; diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c index 202bf1fdfe39..def5caf8f72f 100644 --- a/arch/s390/kernel/machine_kexec.c +++ b/arch/s390/kernel/machine_kexec.c @@ -1,15 +1,10 @@ /* * arch/s390/kernel/machine_kexec.c * - * (C) Copyright IBM Corp. 2005 + * Copyright IBM Corp. 2005,2006 * - * Author(s): Rolf Adelsberger - * - */ - -/* - * s390_machine_kexec.c - handle the transition of Linux booting another kernel - * on the S390 architecture. + * Author(s): Rolf Adelsberger, + * Heiko Carstens */ #include @@ -24,81 +19,53 @@ #include #include -static void kexec_halt_all_cpus(void *); - -typedef void (*relocate_kernel_t) (kimage_entry_t *, unsigned long); +typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long); extern const unsigned char relocate_kernel[]; extern const unsigned long long relocate_kernel_len; -int -machine_kexec_prepare(struct kimage *image) +int machine_kexec_prepare(struct kimage *image) { - unsigned long reboot_code_buffer; + void *reboot_code_buffer; /* We don't support anything but the default image type for now. */ if (image->type != KEXEC_TYPE_DEFAULT) return -EINVAL; /* Get the destination where the assembler code should be copied to.*/ - reboot_code_buffer = page_to_pfn(image->control_code_page)<control_code_page); /* Then copy it */ - memcpy((void *) reboot_code_buffer, relocate_kernel, - relocate_kernel_len); + memcpy(reboot_code_buffer, relocate_kernel, relocate_kernel_len); return 0; } -void -machine_kexec_cleanup(struct kimage *image) +void machine_kexec_cleanup(struct kimage *image) { } -void -machine_shutdown(void) +void machine_shutdown(void) { printk(KERN_INFO "kexec: machine_shutdown called\n"); } -NORET_TYPE void -machine_kexec(struct kimage *image) -{ - on_each_cpu(kexec_halt_all_cpus, image, 0, 0); - for (;;); -} - extern void pfault_fini(void); -static void -kexec_halt_all_cpus(void *kernel_image) +void machine_kexec(struct kimage *image) { - static atomic_t cpuid = ATOMIC_INIT(-1); - int cpu; - struct kimage *image; relocate_kernel_t data_mover; + preempt_disable(); #ifdef CONFIG_PFAULT if (MACHINE_IS_VM) pfault_fini(); #endif - - if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) != -1) - signal_processor(smp_processor_id(), sigp_stop); - - /* 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(); - } - + smp_send_stop(); s390_reset_system(); - image = (struct kimage *) kernel_image; - data_mover = (relocate_kernel_t) - (page_to_pfn(image->control_code_page) << PAGE_SHIFT); + data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page); /* Call the moving routine */ - (*data_mover) (&image->head, image->start); + (*data_mover)(&image->head, image->start); + for (;;); } diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 62822245f9be..b549a43ed08f 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -230,18 +230,37 @@ static inline void do_store_status(void) } } +static inline 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(); } @@ -250,88 +269,28 @@ void smp_send_stop(void) * Reboot, halt and power_off routines for SMP. */ -static void do_machine_restart(void * __unused) -{ - int cpu; - static atomic_t cpuid = ATOMIC_INIT(-1); - - if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) != -1) - signal_processor(smp_processor_id(), sigp_stop); - - /* 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(); - } - - /* Store status of other cpus. */ - do_store_status(); - - /* - * Finally call reipl. Because we waited for all other - * cpus to enter this function we know that they do - * not hold any s390irq-locks (the cpus have been - * interrupted by an external interrupt and s390irq - * locks are always held disabled). - */ - do_reipl(); -} - void machine_restart_smp(char * __unused) { - on_each_cpu(do_machine_restart, NULL, 0, 0); -} - -static void do_wait_for_stop(void) -{ - unsigned long cr[16]; - - __ctl_store(cr, 0, 15); - cr[0] &= ~0xffff; - cr[6] = 0; - __ctl_load(cr, 0, 15); - for (;;) - enabled_wait(); -} - -static void do_machine_halt(void * __unused) -{ - static atomic_t cpuid = ATOMIC_INIT(-1); - - if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) == -1) { - smp_send_stop(); - if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0) - cpcmd(vmhalt_cmd, NULL, 0, NULL); - signal_processor(smp_processor_id(), - sigp_stop_and_store_status); - } - do_wait_for_stop(); + smp_send_stop(); + do_reipl(); } void machine_halt_smp(void) { - on_each_cpu(do_machine_halt, NULL, 0, 0); -} - -static void do_machine_power_off(void * __unused) -{ - static atomic_t cpuid = ATOMIC_INIT(-1); - - if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) == -1) { - smp_send_stop(); - if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0) - cpcmd(vmpoff_cmd, NULL, 0, NULL); - signal_processor(smp_processor_id(), - sigp_stop_and_store_status); - } - do_wait_for_stop(); + smp_send_stop(); + if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0) + __cpcmd(vmhalt_cmd, NULL, 0, NULL); + signal_processor(smp_processor_id(), sigp_stop_and_store_status); + for (;;); } void machine_power_off_smp(void) { - on_each_cpu(do_machine_power_off, NULL, 0, 0); + smp_send_stop(); + if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0) + __cpcmd(vmpoff_cmd, NULL, 0, NULL); + signal_processor(smp_processor_id(), sigp_stop_and_store_status); + for (;;); } /* @@ -860,4 +819,3 @@ EXPORT_SYMBOL(smp_ctl_clear_bit); EXPORT_SYMBOL(smp_call_function); EXPORT_SYMBOL(smp_get_cpu); EXPORT_SYMBOL(smp_put_cpu); - diff --git a/drivers/s390/char/sclp_quiesce.c b/drivers/s390/char/sclp_quiesce.c index 32004aae95c1..ffa9282ce97a 100644 --- a/drivers/s390/char/sclp_quiesce.c +++ b/drivers/s390/char/sclp_quiesce.c @@ -19,52 +19,17 @@ #include "sclp.h" - -#ifdef CONFIG_SMP -/* Signal completion of shutdown process. All CPUs except the first to enter - * this function: go to stopped state. First CPU: wait until all other - * CPUs are in stopped or check stop state. Afterwards, load special PSW - * to indicate completion. */ -static void -do_load_quiesce_psw(void * __unused) -{ - static atomic_t cpuid = ATOMIC_INIT(-1); - psw_t quiesce_psw; - int cpu; - - if (atomic_cmpxchg(&cpuid, -1, smp_processor_id()) != -1) - signal_processor(smp_processor_id(), sigp_stop); - /* 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(); - } - /* Quiesce the last cpu with the special psw */ - quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT; - quiesce_psw.addr = 0xfff; - __load_psw(quiesce_psw); -} - -/* Shutdown handler. Perform shutdown function on all CPUs. */ -static void -do_machine_quiesce(void) -{ - on_each_cpu(do_load_quiesce_psw, NULL, 0, 0); -} -#else /* Shutdown handler. Signal completion of shutdown by loading special PSW. */ static void do_machine_quiesce(void) { psw_t quiesce_psw; + smp_send_stop(); quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT; quiesce_psw.addr = 0xfff; __load_psw(quiesce_psw); } -#endif /* Handler for quiesce event. Start shutdown procedure. */ static void diff --git a/include/asm-s390/smp.h b/include/asm-s390/smp.h index c3cf030ada4d..7097c96ed026 100644 --- a/include/asm-s390/smp.h +++ b/include/asm-s390/smp.h @@ -18,6 +18,7 @@ #include #include +#include /* s390 specific smp.c headers @@ -101,6 +102,13 @@ smp_call_function_on(void (*func) (void *info), void *info, func(info); return 0; } + +static inline void smp_send_stop(void) +{ + /* Disable all interrupts/machine checks */ + __load_psw_mask(PSW_KERNEL_BITS & ~PSW_MASK_MCHECK); +} + #define smp_cpu_not_running(cpu) 1 #define smp_get_cpu(cpu) ({ 0; }) #define smp_put_cpu(cpu) ({ 0; })