X-Git-Url: https://git.stricted.de/?p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git;a=blobdiff_plain;f=arch%2Farm64%2Fkernel%2Fsmp.c;h=7d850f9a0c2b72465354d7cf32ee07ce066e462a;hp=b0a8703a25ecdca15ee675696cf527ce9158d411;hb=4a2455f795a889c7c76c55abe4ce50bdd5175e5f;hpb=5cfc71ce138e79ceb6250f78137dd05ba52e9d34 diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index b0a8703a25ec..7d850f9a0c2b 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -48,13 +49,17 @@ #include #include +#include + +#define CREATE_TRACE_POINTS +#include + /* * as from 2.5, kernels no longer have an init_tasks structure * so we need some other way of telling a new secondary core * where to place its SVC stack */ struct secondary_data secondary_data; -volatile unsigned long secondary_holding_pen_release = INVALID_HWID; enum ipi_msg_type { IPI_RESCHEDULE, @@ -63,61 +68,16 @@ enum ipi_msg_type { IPI_CPU_STOP, }; -static DEFINE_RAW_SPINLOCK(boot_lock); - -/* - * Write secondary_holding_pen_release in a way that is guaranteed to be - * visible to all observers, irrespective of whether they're taking part - * in coherency or not. This is necessary for the hotplug code to work - * reliably. - */ -static void __cpuinit write_pen_release(u64 val) -{ - void *start = (void *)&secondary_holding_pen_release; - unsigned long size = sizeof(secondary_holding_pen_release); - - secondary_holding_pen_release = val; - __flush_dcache_area(start, size); -} - /* * Boot a secondary CPU, and assign it the specified idle task. * This also gives us the initial stack to use for this CPU. */ static int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) { - unsigned long timeout; - - /* - * Set synchronisation state between this boot processor - * and the secondary one - */ - raw_spin_lock(&boot_lock); - - /* - * Update the pen release flag. - */ - write_pen_release(cpu_logical_map(cpu)); - - /* - * Send an event, causing the secondaries to read pen_release. - */ - sev(); - - timeout = jiffies + (1 * HZ); - while (time_before(jiffies, timeout)) { - if (secondary_holding_pen_release == INVALID_HWID) - break; - udelay(10); - } + if (cpu_ops[cpu]->cpu_boot) + return cpu_ops[cpu]->cpu_boot(cpu); - /* - * Now the secondary core is starting up let it run its - * calibrations, then wait for it to finish - */ - raw_spin_unlock(&boot_lock); - - return secondary_holding_pen_release != INVALID_HWID ? -ENOSYS : 0; + return -EOPNOTSUPP; } static DECLARE_COMPLETION(cpu_running); @@ -158,6 +118,11 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) return ret; } +static void __cpuinit smp_store_cpu_info(unsigned int cpuid) +{ + store_cpu_topology(cpuid); +} + /* * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. @@ -177,6 +142,8 @@ asmlinkage void __cpuinit secondary_start_kernel(void) current->active_mm = mm; cpumask_set_cpu(cpu, mm_cpumask(mm)); + set_my_cpu_offset(per_cpu_offset(smp_processor_id())); + /* * TTBR0 is only used for the identity mapping at this stage. Make it * point to zero page to avoid speculatively fetching new entries. @@ -187,17 +154,8 @@ asmlinkage void __cpuinit secondary_start_kernel(void) preempt_disable(); trace_hardirqs_off(); - /* - * Let the primary processor know we're out of the - * pen, then head off into the C entry point - */ - write_pen_release(INVALID_HWID); - - /* - * Synchronise with the boot thread. - */ - raw_spin_lock(&boot_lock); - raw_spin_unlock(&boot_lock); + if (cpu_ops[cpu]->cpu_postboot) + cpu_ops[cpu]->cpu_postboot(); /* * Log the CPU info before it is marked online and might get read. @@ -212,11 +170,14 @@ asmlinkage void __cpuinit secondary_start_kernel(void) set_cpu_online(cpu, true); complete(&cpu_running); + smp_store_cpu_info(cpu); + /* * Enable GIC and timers. */ notify_cpu_starting(cpu); + local_dbg_enable(); local_irq_enable(); local_fiq_enable(); @@ -226,41 +187,136 @@ asmlinkage void __cpuinit secondary_start_kernel(void) cpu_startup_entry(CPUHP_ONLINE); } -void __init smp_cpus_done(unsigned int max_cpus) +#ifdef CONFIG_HOTPLUG_CPU +static int op_cpu_disable(unsigned int cpu) { - unsigned long bogosum = loops_per_jiffy * num_online_cpus(); + /* + * If we don't have a cpu_die method, abort before we reach the point + * of no return. CPU0 may not have an cpu_ops, so test for it. + */ + if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_die) + return -EOPNOTSUPP; - pr_info("SMP: Total of %d processors activated (%lu.%02lu BogoMIPS).\n", - num_online_cpus(), bogosum / (500000/HZ), - (bogosum / (5000/HZ)) % 100); + /* + * We may need to abort a hot unplug for some other mechanism-specific + * reason. + */ + if (cpu_ops[cpu]->cpu_disable) + return cpu_ops[cpu]->cpu_disable(cpu); + + return 0; } -void __init smp_prepare_boot_cpu(void) +/* + * __cpu_disable runs on the processor to be shutdown. + */ +int __cpu_disable(void) { -} + unsigned int cpu = smp_processor_id(); + int ret; -static void (*smp_cross_call)(const struct cpumask *, unsigned int); + ret = op_cpu_disable(cpu); + if (ret) + return ret; -static const struct smp_enable_ops *enable_ops[] __initconst = { - &smp_spin_table_ops, - &smp_psci_ops, - NULL, -}; + /* + * Take this CPU offline. Once we clear this, we can't return, + * and we must not schedule until we're ready to give up the cpu. + */ + set_cpu_online(cpu, false); -static const struct smp_enable_ops *smp_enable_ops[NR_CPUS]; + /* + * OK - migrate IRQs away from this CPU + */ + migrate_irqs(); + + /* + * Remove this CPU from the vm mask set of all processes. + */ + clear_tasks_mm_cpumask(cpu); -static const struct smp_enable_ops * __init smp_get_enable_ops(const char *name) + return 0; +} + +static int op_cpu_kill(unsigned int cpu) { - const struct smp_enable_ops **ops = enable_ops; + /* + * If we have no means of synchronising with the dying CPU, then assume + * that it is really dead. We can only wait for an arbitrary length of + * time and hope that it's dead, so let's skip the wait and just hope. + */ + if (!cpu_ops[cpu]->cpu_kill) + return 1; - while (*ops) { - if (!strcmp(name, (*ops)->name)) - return *ops; + return cpu_ops[cpu]->cpu_kill(cpu); +} + +static DECLARE_COMPLETION(cpu_died); - ops++; +/* + * called on the thread which is asking for a CPU to be shutdown - + * waits until shutdown has completed, or it is timed out. + */ +void __cpu_die(unsigned int cpu) +{ + if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) { + pr_crit("CPU%u: cpu didn't die\n", cpu); + return; } + pr_notice("CPU%u: shutdown\n", cpu); + + /* + * Now that the dying CPU is beyond the point of no return w.r.t. + * in-kernel synchronisation, try to get the firwmare to help us to + * verify that it has really left the kernel before we consider + * clobbering anything it might still be using. + */ + if (!op_cpu_kill(cpu)) + pr_warn("CPU%d may not have shut down cleanly\n", cpu); +} + +/* + * Called from the idle thread for the CPU which has been shutdown. + * + * Note that we disable IRQs here, but do not re-enable them + * before returning to the caller. This is also the behaviour + * of the other hotplug-cpu capable cores, so presumably coming + * out of idle fixes this. + */ +void cpu_die(void) +{ + unsigned int cpu = smp_processor_id(); + + idle_task_exit(); + + local_irq_disable(); + + /* Tell __cpu_die() that this CPU is now safe to dispose of */ + complete(&cpu_died); + + /* + * Actually shutdown the CPU. This must never fail. The specific hotplug + * mechanism must perform all required cache maintenance to ensure that + * no dirty lines are lost in the process of shutting down the CPU. + */ + cpu_ops[cpu]->cpu_die(cpu); - return NULL; + BUG(); +} +#endif + +void __init smp_cpus_done(unsigned int max_cpus) +{ + unsigned long bogosum = loops_per_jiffy * num_online_cpus(); + + pr_info("SMP: Total of %d processors activated (%lu.%02lu BogoMIPS).\n", + num_online_cpus(), bogosum / (500000/HZ), + (bogosum / (5000/HZ)) % 100); +} + +void __init smp_prepare_boot_cpu(void) +{ + set_my_cpu_offset(per_cpu_offset(smp_processor_id())); } /* @@ -270,9 +326,8 @@ static const struct smp_enable_ops * __init smp_get_enable_ops(const char *name) */ void __init smp_init_cpus(void) { - const char *enable_method; struct device_node *dn = NULL; - int i, cpu = 1; + unsigned int i, cpu = 1; bool bootcpu_valid = false; while ((dn = of_find_node_by_type(dn, "cpu"))) { @@ -341,25 +396,10 @@ void __init smp_init_cpus(void) if (cpu >= NR_CPUS) goto next; - /* - * We currently support only the "spin-table" enable-method. - */ - enable_method = of_get_property(dn, "enable-method", NULL); - if (!enable_method) { - pr_err("%s: missing enable-method property\n", - dn->full_name); + if (cpu_read_ops(dn, cpu) != 0) goto next; - } - - smp_enable_ops[cpu] = smp_get_enable_ops(enable_method); - - if (!smp_enable_ops[cpu]) { - pr_err("%s: invalid enable-method property: %s\n", - dn->full_name, enable_method); - goto next; - } - if (smp_enable_ops[cpu]->init_cpu(dn, cpu)) + if (cpu_ops[cpu]->cpu_init(dn, cpu)) goto next; pr_debug("cpu logical map 0x%llx\n", hwid); @@ -389,8 +429,13 @@ next: void __init smp_prepare_cpus(unsigned int max_cpus) { - int cpu, err; - unsigned int ncores = num_possible_cpus(); + int err; + unsigned int cpu, ncores = num_possible_cpus(); + + init_cpu_topology(); + + smp_store_cpu_info(smp_processor_id()); + /* * are we trying to boot more cores than exist? @@ -417,10 +462,10 @@ void __init smp_prepare_cpus(unsigned int max_cpus) if (cpu == smp_processor_id()) continue; - if (!smp_enable_ops[cpu]) + if (!cpu_ops[cpu]) continue; - err = smp_enable_ops[cpu]->prepare_cpu(cpu); + err = cpu_ops[cpu]->cpu_prepare(cpu); if (err) continue; @@ -429,36 +474,33 @@ void __init smp_prepare_cpus(unsigned int max_cpus) } } +static void (*__smp_cross_call)(const struct cpumask *, unsigned int); void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int)) { - smp_cross_call = fn; + __smp_cross_call = fn; } -void arch_send_call_function_ipi_mask(const struct cpumask *mask) -{ - smp_cross_call(mask, IPI_CALL_FUNC); -} - -void arch_send_call_function_single_ipi(int cpu) -{ - smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); -} - -static const char *ipi_types[NR_IPI] = { -#define S(x,s) [x - IPI_RESCHEDULE] = s +static const char *ipi_types[NR_IPI] __tracepoint_string = { +#define S(x,s) [x] = s S(IPI_RESCHEDULE, "Rescheduling interrupts"), S(IPI_CALL_FUNC, "Function call interrupts"), S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"), S(IPI_CPU_STOP, "CPU stop interrupts"), }; +static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) +{ + trace_ipi_raise(target, ipi_types[ipinr]); + __smp_cross_call(target, ipinr); +} + void show_ipi_list(struct seq_file *p, int prec) { unsigned int cpu, i; for (i = 0; i < NR_IPI; i++) { - seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i + IPI_RESCHEDULE, + seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : ""); for_each_present_cpu(cpu) seq_printf(p, "%10u ", @@ -478,6 +520,16 @@ u64 smp_irq_stat_cpu(unsigned int cpu) return sum; } +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + smp_cross_call(mask, IPI_CALL_FUNC); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); +} + static DEFINE_RAW_SPINLOCK(stop_lock); /* @@ -510,8 +562,10 @@ void handle_IPI(int ipinr, struct pt_regs *regs) unsigned int cpu = smp_processor_id(); struct pt_regs *old_regs = set_irq_regs(regs); - if (ipinr >= IPI_RESCHEDULE && ipinr < IPI_RESCHEDULE + NR_IPI) - __inc_irq_stat(cpu, ipi_irqs[ipinr - IPI_RESCHEDULE]); + if ((unsigned)ipinr < NR_IPI) { + trace_ipi_entry(ipi_types[ipinr]); + __inc_irq_stat(cpu, ipi_irqs[ipinr]); + } switch (ipinr) { case IPI_RESCHEDULE: @@ -520,19 +574,25 @@ void handle_IPI(int ipinr, struct pt_regs *regs) case IPI_CALL_FUNC: irq_enter(); + mt_trace_ISR_start(ipinr); generic_smp_call_function_interrupt(); + mt_trace_ISR_end(ipinr); irq_exit(); break; case IPI_CALL_FUNC_SINGLE: irq_enter(); + mt_trace_ISR_start(ipinr); generic_smp_call_function_single_interrupt(); + mt_trace_ISR_end(ipinr); irq_exit(); break; case IPI_CPU_STOP: irq_enter(); + mt_trace_ISR_start(ipinr); ipi_cpu_stop(cpu); + mt_trace_ISR_end(ipinr); irq_exit(); break; @@ -540,6 +600,9 @@ void handle_IPI(int ipinr, struct pt_regs *regs) pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr); break; } + + if ((unsigned)ipinr < NR_IPI) + trace_ipi_exit(ipi_types[ipinr]); set_irq_regs(old_regs); }