diff options
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/smp.h | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/smp.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 165 | ||||
| -rw-r--r-- | arch/x86/xen/smp_hvm.c | 16 | ||||
| -rw-r--r-- | arch/x86/xen/smp_pv.c | 39 |
6 files changed, 75 insertions, 154 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d0191338a102..adb1ec8503d0 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -274,6 +274,7 @@ config X86 select HAVE_UNSTABLE_SCHED_CLOCK select HAVE_USER_RETURN_NOTIFIER select HAVE_GENERIC_VDSO + select HOTPLUG_CORE_SYNC_FULL if SMP select HOTPLUG_SMT if SMP select IRQ_FORCED_THREADING select NEED_PER_CPU_EMBED_FIRST_CHUNK diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index 0ec4c64a1981..693c9997c069 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -38,6 +38,8 @@ struct smp_ops { void (*crash_stop_other_cpus)(void); void (*smp_send_reschedule)(int cpu); + void (*cleanup_dead_cpu)(unsigned cpu); + void (*poll_sync_state)(void); int (*cpu_up)(unsigned cpu, struct task_struct *tidle); int (*cpu_disable)(void); void (*cpu_die)(unsigned int cpu); @@ -90,7 +92,8 @@ static inline int __cpu_disable(void) static inline void __cpu_die(unsigned int cpu) { - smp_ops.cpu_die(cpu); + if (smp_ops.cpu_die) + smp_ops.cpu_die(cpu); } static inline void __noreturn play_dead(void) @@ -123,8 +126,6 @@ void native_smp_cpus_done(unsigned int max_cpus); int common_cpu_up(unsigned int cpunum, struct task_struct *tidle); int native_cpu_up(unsigned int cpunum, struct task_struct *tidle); int native_cpu_disable(void); -int common_cpu_die(unsigned int cpu); -void native_cpu_die(unsigned int cpu); void __noreturn hlt_play_dead(void); void native_play_dead(void); void play_dead_common(void); diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index 375b33ecafa2..4f6375b4ba9a 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c @@ -269,7 +269,6 @@ struct smp_ops smp_ops = { .smp_send_reschedule = native_smp_send_reschedule, .cpu_up = native_cpu_up, - .cpu_die = native_cpu_die, .cpu_disable = native_cpu_disable, .play_dead = native_play_dead, diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 4349e8ab2566..59386419b4b1 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -57,6 +57,7 @@ #include <linux/pgtable.h> #include <linux/overflow.h> #include <linux/stackprotector.h> +#include <linux/cpuhotplug.h> #include <asm/acpi.h> #include <asm/cacheinfo.h> @@ -101,9 +102,6 @@ EXPORT_PER_CPU_SYMBOL(cpu_die_map); DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); EXPORT_PER_CPU_SYMBOL(cpu_info); -/* All of these masks are initialized in setup_cpu_local_masks() */ -static cpumask_var_t cpu_initialized_mask; -static cpumask_var_t cpu_callout_mask; /* Representing CPUs for which sibling maps can be computed */ static cpumask_var_t cpu_sibling_setup_mask; @@ -166,10 +164,10 @@ static void ap_starting(void) int cpuid = smp_processor_id(); /* - * If woken up by an INIT in an 82489DX configuration - * cpu_callout_mask guarantees the CPU does not reach this point - * before an INIT_deassert IPI reaches the local APIC, so it is now - * safe to touch the local APIC. + * If woken up by an INIT in an 82489DX configuration the alive + * synchronization guarantees that the CPU does not reach this + * point before an INIT_deassert IPI reaches the local APIC, so it + * is now safe to touch the local APIC. * * Set up this CPU, first the APIC, which is probably redundant on * most boards. @@ -213,17 +211,6 @@ static void ap_calibrate_delay(void) cpu_data(smp_processor_id()).loops_per_jiffy = loops_per_jiffy; } -static void wait_for_master_cpu(int cpu) -{ - /* - * Wait for release by control CPU before continuing with AP - * initialization. - */ - WARN_ON(cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)); - while (!cpumask_test_cpu(cpu, cpu_callout_mask)) - cpu_relax(); -} - /* * Activate a secondary processor. */ @@ -244,11 +231,11 @@ static void notrace start_secondary(void *unused) cpu_init_exception_handling(); /* - * Sync point with wait_cpu_initialized(). Sets AP in - * cpu_initialized_mask and then waits for the control CPU - * to release it. + * Synchronization point with the hotplug core. Sets the + * synchronization state to ALIVE and waits for the control CPU to + * release this CPU for further bringup. */ - wait_for_master_cpu(raw_smp_processor_id()); + cpuhp_ap_sync_alive(); cpu_init(); rcu_cpu_starting(raw_smp_processor_id()); @@ -278,7 +265,6 @@ static void notrace start_secondary(void *unused) set_cpu_online(smp_processor_id(), true); lapic_online(); unlock_vector_lock(); - cpu_set_state_online(smp_processor_id()); x86_platform.nmi_init(); /* enable local interrupts */ @@ -729,9 +715,9 @@ static void impress_friends(void) * Allow the user to impress friends. */ pr_debug("Before bogomips\n"); - for_each_possible_cpu(cpu) - if (cpumask_test_cpu(cpu, cpu_callout_mask)) - bogosum += cpu_data(cpu).loops_per_jiffy; + for_each_online_cpu(cpu) + bogosum += cpu_data(cpu).loops_per_jiffy; + pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n", num_online_cpus(), bogosum/(500000/HZ), @@ -1003,6 +989,7 @@ int common_cpu_up(unsigned int cpu, struct task_struct *idle) static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle) { unsigned long start_ip = real_mode_header->trampoline_start; + int ret; #ifdef CONFIG_X86_64 /* If 64-bit wakeup method exists, use the 64-bit mode trampoline IP */ @@ -1043,13 +1030,6 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle) } } - /* - * AP might wait on cpu_callout_mask in cpu_init() with - * cpu_initialized_mask set if previous attempt to online - * it timed-out. Clear cpu_initialized_mask so that after - * INIT/SIPI it could start with a clean state. - */ - cpumask_clear_cpu(cpu, cpu_initialized_mask); smp_mb(); /* @@ -1060,47 +1040,16 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle) * - Use an INIT boot APIC message */ if (apic->wakeup_secondary_cpu_64) - return apic->wakeup_secondary_cpu_64(apicid, start_ip); + ret = apic->wakeup_secondary_cpu_64(apicid, start_ip); else if (apic->wakeup_secondary_cpu) - return apic->wakeup_secondary_cpu(apicid, start_ip); - - return wakeup_secondary_cpu_via_init(apicid, start_ip); -} - -static int wait_cpu_cpumask(unsigned int cpu, const struct cpumask *mask) -{ - unsigned long timeout; - - /* - * Wait up to 10s for the CPU to report in. - */ - timeout = jiffies + 10*HZ; - while (time_before(jiffies, timeout)) { - if (cpumask_test_cpu(cpu, mask)) - return 0; - - schedule(); - } - return -1; -} - -/* - * Bringup step two: Wait for the target AP to reach cpu_init_secondary() - * and thus wait_for_master_cpu(), then set cpu_callout_mask to allow it - * to proceed. The AP will then proceed past setting its 'callin' bit - * and end up waiting in check_tsc_sync_target() until we reach - * wait_cpu_online() to tend to it. - */ -static int wait_cpu_initialized(unsigned int cpu) -{ - /* - * Wait for first sign of life from AP. - */ - if (wait_cpu_cpumask(cpu, cpu_initialized_mask)) - return -1; + ret = apic->wakeup_secondary_cpu(apicid, start_ip); + else + ret = wakeup_secondary_cpu_via_init(apicid, start_ip); - cpumask_set_cpu(cpu, cpu_callout_mask); - return 0; + /* If the wakeup mechanism failed, cleanup the warm reset vector */ + if (ret) + arch_cpuhp_cleanup_kick_cpu(cpu); + return ret; } static int native_kick_ap(unsigned int cpu, struct task_struct *tidle) @@ -1125,11 +1074,6 @@ static int native_kick_ap(unsigned int cpu, struct task_struct *tidle) */ mtrr_save_state(); - /* x86 CPUs take themselves offline, so delayed offline is OK. */ - err = cpu_check_up_prepare(cpu); - if (err && err != -EBUSY) - return err; - /* the FPU context is blank, nobody can own it */ per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL; @@ -1146,17 +1090,29 @@ static int native_kick_ap(unsigned int cpu, struct task_struct *tidle) int native_cpu_up(unsigned int cpu, struct task_struct *tidle) { - int ret; - - ret = native_kick_ap(cpu, tidle); - if (!ret) - ret = wait_cpu_initialized(cpu); + return native_kick_ap(cpu, tidle); +} +void arch_cpuhp_cleanup_kick_cpu(unsigned int cpu) +{ /* Cleanup possible dangling ends... */ - if (x86_platform.legacy.warm_reset) + if (smp_ops.cpu_up == native_cpu_up && x86_platform.legacy.warm_reset) smpboot_restore_warm_reset_vector(); +} - return ret; +void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu) +{ + if (smp_ops.cleanup_dead_cpu) + smp_ops.cleanup_dead_cpu(cpu); + + if (system_state == SYSTEM_RUNNING) + pr_info("CPU %u is now offline\n", cpu); +} + +void arch_cpuhp_sync_state_poll(void) +{ + if (smp_ops.poll_sync_state) + smp_ops.poll_sync_state(); } /** @@ -1348,9 +1304,6 @@ void __init native_smp_prepare_boot_cpu(void) if (!IS_ENABLED(CONFIG_SMP)) switch_gdt_and_percpu_base(me); - /* already set me in cpu_online_mask in boot_cpu_init() */ - cpumask_set_cpu(me, cpu_callout_mask); - cpu_set_state_online(me); native_pv_lock_init(); } @@ -1477,8 +1430,6 @@ __init void prefill_possible_map(void) /* correctly size the local cpu masks */ void __init setup_cpu_local_masks(void) { - alloc_bootmem_cpumask_var(&cpu_initialized_mask); - alloc_bootmem_cpumask_var(&cpu_callout_mask); alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask); } @@ -1540,9 +1491,6 @@ static void remove_siblinginfo(int cpu) static void remove_cpu_from_maps(int cpu) { set_cpu_online(cpu, false); - cpumask_clear_cpu(cpu, cpu_callout_mask); - /* was set by cpu_init() */ - cpumask_clear_cpu(cpu, cpu_initialized_mask); numa_remove_cpu(cpu); } @@ -1593,36 +1541,11 @@ int native_cpu_disable(void) return 0; } -int common_cpu_die(unsigned int cpu) -{ - int ret = 0; - - /* We don't do anything here: idle task is faking death itself. */ - - /* They ack this in play_dead() by setting CPU_DEAD */ - if (cpu_wait_death(cpu, 5)) { - if (system_state == SYSTEM_RUNNING) - pr_info("CPU %u is now offline\n", cpu); - } else { - pr_err("CPU %u didn't die...\n", cpu); - ret = -1; - } - - return ret; -} - -void native_cpu_die(unsigned int cpu) -{ - common_cpu_die(cpu); -} - void play_dead_common(void) { idle_task_exit(); - /* Ack it */ - (void)cpu_report_death(); - + cpuhp_ap_report_dead(); /* * With physical CPU hotplug, we should halt the cpu */ @@ -1724,12 +1647,6 @@ int native_cpu_disable(void) return -ENOSYS; } -void native_cpu_die(unsigned int cpu) -{ - /* We said "no" in __cpu_disable */ - BUG(); -} - void native_play_dead(void) { BUG(); diff --git a/arch/x86/xen/smp_hvm.c b/arch/x86/xen/smp_hvm.c index b70afdff419c..ac95d1981cc0 100644 --- a/arch/x86/xen/smp_hvm.c +++ b/arch/x86/xen/smp_hvm.c @@ -55,18 +55,16 @@ static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus) } #ifdef CONFIG_HOTPLUG_CPU -static void xen_hvm_cpu_die(unsigned int cpu) +static void xen_hvm_cleanup_dead_cpu(unsigned int cpu) { - if (common_cpu_die(cpu) == 0) { - if (xen_have_vector_callback) { - xen_smp_intr_free(cpu); - xen_uninit_lock_cpu(cpu); - xen_teardown_timer(cpu); - } + if (xen_have_vector_callback) { + xen_smp_intr_free(cpu); + xen_uninit_lock_cpu(cpu); + xen_teardown_timer(cpu); } } #else -static void xen_hvm_cpu_die(unsigned int cpu) +static void xen_hvm_cleanup_dead_cpu(unsigned int cpu) { BUG(); } @@ -77,7 +75,7 @@ void __init xen_hvm_smp_init(void) smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu; smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus; smp_ops.smp_cpus_done = xen_smp_cpus_done; - smp_ops.cpu_die = xen_hvm_cpu_die; + smp_ops.cleanup_dead_cpu = xen_hvm_cleanup_dead_cpu; if (!xen_have_vector_callback) { #ifdef CONFIG_PARAVIRT_SPINLOCKS diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c index be40927667cf..b089fb1cefc6 100644 --- a/arch/x86/xen/smp_pv.c +++ b/arch/x86/xen/smp_pv.c @@ -62,6 +62,7 @@ static void cpu_bringup(void) int cpu; cr4_init(); + cpuhp_ap_sync_alive(); cpu_init(); touch_softlockup_watchdog(); @@ -83,7 +84,7 @@ static void cpu_bringup(void) set_cpu_online(cpu, true); - cpu_set_state_online(cpu); /* Implies full memory barrier. */ + smp_mb(); /* We can take interrupts now: we're officially "up". */ local_irq_enable(); @@ -323,14 +324,6 @@ static int xen_pv_cpu_up(unsigned int cpu, struct task_struct *idle) xen_setup_runstate_info(cpu); - /* - * PV VCPUs are always successfully taken down (see 'while' loop - * in xen_cpu_die()), so -EBUSY is an error. - */ - rc = cpu_check_up_prepare(cpu); - if (rc) - return rc; - /* make sure interrupts start blocked */ per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1; @@ -349,6 +342,11 @@ static int xen_pv_cpu_up(unsigned int cpu, struct task_struct *idle) return 0; } +static void xen_pv_poll_sync_state(void) +{ + HYPERVISOR_sched_op(SCHEDOP_yield, NULL); +} + #ifdef CONFIG_HOTPLUG_CPU static int xen_pv_cpu_disable(void) { @@ -364,18 +362,18 @@ static int xen_pv_cpu_disable(void) static void xen_pv_cpu_die(unsigned int cpu) { - while (HYPERVISOR_vcpu_op(VCPUOP_is_up, - xen_vcpu_nr(cpu), NULL)) { + while (HYPERVISOR_vcpu_op(VCPUOP_is_up, xen_vcpu_nr(cpu), NULL)) { __set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(HZ/10); } +} - if (common_cpu_die(cpu) == 0) { - xen_smp_intr_free(cpu); - xen_uninit_lock_cpu(cpu); - xen_teardown_timer(cpu); - xen_pmu_finish(cpu); - } +static void xen_pv_cleanup_dead_cpu(unsigned int cpu) +{ + xen_smp_intr_free(cpu); + xen_uninit_lock_cpu(cpu); + xen_teardown_timer(cpu); + xen_pmu_finish(cpu); } static void __noreturn xen_pv_play_dead(void) /* used only with HOTPLUG_CPU */ @@ -397,6 +395,11 @@ static void xen_pv_cpu_die(unsigned int cpu) BUG(); } +static void xen_pv_cleanup_dead_cpu(unsigned int cpu) +{ + BUG(); +} + static void __noreturn xen_pv_play_dead(void) { BUG(); @@ -437,6 +440,8 @@ static const struct smp_ops xen_smp_ops __initconst = { .cpu_up = xen_pv_cpu_up, .cpu_die = xen_pv_cpu_die, + .cleanup_dead_cpu = xen_pv_cleanup_dead_cpu, + .poll_sync_state = xen_pv_poll_sync_state, .cpu_disable = xen_pv_cpu_disable, .play_dead = xen_pv_play_dead, |