From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- arch/alpha/kernel/smp.c | 825 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 825 insertions(+) create mode 100644 arch/alpha/kernel/smp.c (limited to 'arch/alpha/kernel/smp.c') diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c new file mode 100644 index 00000000..d7397036 --- /dev/null +++ b/arch/alpha/kernel/smp.c @@ -0,0 +1,825 @@ +/* + * linux/arch/alpha/kernel/smp.c + * + * 2001-07-09 Phil Ezolt (Phillip.Ezolt@compaq.com) + * Renamed modified smp_call_function to smp_call_function_on_cpu() + * Created an function that conforms to the old calling convention + * of smp_call_function(). + * + * This is helpful for DCPI. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include "proto.h" +#include "irq_impl.h" + + +#define DEBUG_SMP 0 +#if DEBUG_SMP +#define DBGS(args) printk args +#else +#define DBGS(args) +#endif + +/* A collection of per-processor data. */ +struct cpuinfo_alpha cpu_data[NR_CPUS]; +EXPORT_SYMBOL(cpu_data); + +/* A collection of single bit ipi messages. */ +static struct { + unsigned long bits ____cacheline_aligned; +} ipi_data[NR_CPUS] __cacheline_aligned; + +enum ipi_message_type { + IPI_RESCHEDULE, + IPI_CALL_FUNC, + IPI_CALL_FUNC_SINGLE, + IPI_CPU_STOP, +}; + +/* Set to a secondary's cpuid when it comes online. */ +static int smp_secondary_alive __devinitdata = 0; + +int smp_num_probed; /* Internal processor count */ +int smp_num_cpus = 1; /* Number that came online. */ +EXPORT_SYMBOL(smp_num_cpus); + +/* + * Called by both boot and secondaries to move global data into + * per-processor storage. + */ +static inline void __init +smp_store_cpu_info(int cpuid) +{ + cpu_data[cpuid].loops_per_jiffy = loops_per_jiffy; + cpu_data[cpuid].last_asn = ASN_FIRST_VERSION; + cpu_data[cpuid].need_new_asn = 0; + cpu_data[cpuid].asn_lock = 0; +} + +/* + * Ideally sets up per-cpu profiling hooks. Doesn't do much now... + */ +static inline void __init +smp_setup_percpu_timer(int cpuid) +{ + cpu_data[cpuid].prof_counter = 1; + cpu_data[cpuid].prof_multiplier = 1; +} + +static void __init +wait_boot_cpu_to_stop(int cpuid) +{ + unsigned long stop = jiffies + 10*HZ; + + while (time_before(jiffies, stop)) { + if (!smp_secondary_alive) + return; + barrier(); + } + + printk("wait_boot_cpu_to_stop: FAILED on CPU %d, hanging now\n", cpuid); + for (;;) + barrier(); +} + +/* + * Where secondaries begin a life of C. + */ +void __cpuinit +smp_callin(void) +{ + int cpuid = hard_smp_processor_id(); + + if (cpu_online(cpuid)) { + printk("??, cpu 0x%x already present??\n", cpuid); + BUG(); + } + set_cpu_online(cpuid, true); + + /* Turn on machine checks. */ + wrmces(7); + + /* Set trap vectors. */ + trap_init(); + + /* Set interrupt vector. */ + wrent(entInt, 0); + + /* Get our local ticker going. */ + smp_setup_percpu_timer(cpuid); + + /* Call platform-specific callin, if specified */ + if (alpha_mv.smp_callin) alpha_mv.smp_callin(); + + /* All kernel threads share the same mm context. */ + atomic_inc(&init_mm.mm_count); + current->active_mm = &init_mm; + + /* inform the notifiers about the new cpu */ + notify_cpu_starting(cpuid); + + /* Must have completely accurate bogos. */ + local_irq_enable(); + + /* Wait boot CPU to stop with irq enabled before running + calibrate_delay. */ + wait_boot_cpu_to_stop(cpuid); + mb(); + calibrate_delay(); + + smp_store_cpu_info(cpuid); + /* Allow master to continue only after we written loops_per_jiffy. */ + wmb(); + smp_secondary_alive = 1; + + DBGS(("smp_callin: commencing CPU %d current %p active_mm %p\n", + cpuid, current, current->active_mm)); + + /* Do nothing. */ + cpu_idle(); +} + +/* Wait until hwrpb->txrdy is clear for cpu. Return -1 on timeout. */ +static int __devinit +wait_for_txrdy (unsigned long cpumask) +{ + unsigned long timeout; + + if (!(hwrpb->txrdy & cpumask)) + return 0; + + timeout = jiffies + 10*HZ; + while (time_before(jiffies, timeout)) { + if (!(hwrpb->txrdy & cpumask)) + return 0; + udelay(10); + barrier(); + } + + return -1; +} + +/* + * Send a message to a secondary's console. "START" is one such + * interesting message. ;-) + */ +static void __cpuinit +send_secondary_console_msg(char *str, int cpuid) +{ + struct percpu_struct *cpu; + register char *cp1, *cp2; + unsigned long cpumask; + size_t len; + + cpu = (struct percpu_struct *) + ((char*)hwrpb + + hwrpb->processor_offset + + cpuid * hwrpb->processor_size); + + cpumask = (1UL << cpuid); + if (wait_for_txrdy(cpumask)) + goto timeout; + + cp2 = str; + len = strlen(cp2); + *(unsigned int *)&cpu->ipc_buffer[0] = len; + cp1 = (char *) &cpu->ipc_buffer[1]; + memcpy(cp1, cp2, len); + + /* atomic test and set */ + wmb(); + set_bit(cpuid, &hwrpb->rxrdy); + + if (wait_for_txrdy(cpumask)) + goto timeout; + return; + + timeout: + printk("Processor %x not ready\n", cpuid); +} + +/* + * A secondary console wants to send a message. Receive it. + */ +static void +recv_secondary_console_msg(void) +{ + int mycpu, i, cnt; + unsigned long txrdy = hwrpb->txrdy; + char *cp1, *cp2, buf[80]; + struct percpu_struct *cpu; + + DBGS(("recv_secondary_console_msg: TXRDY 0x%lx.\n", txrdy)); + + mycpu = hard_smp_processor_id(); + + for (i = 0; i < NR_CPUS; i++) { + if (!(txrdy & (1UL << i))) + continue; + + DBGS(("recv_secondary_console_msg: " + "TXRDY contains CPU %d.\n", i)); + + cpu = (struct percpu_struct *) + ((char*)hwrpb + + hwrpb->processor_offset + + i * hwrpb->processor_size); + + DBGS(("recv_secondary_console_msg: on %d from %d" + " HALT_REASON 0x%lx FLAGS 0x%lx\n", + mycpu, i, cpu->halt_reason, cpu->flags)); + + cnt = cpu->ipc_buffer[0] >> 32; + if (cnt <= 0 || cnt >= 80) + strcpy(buf, "<<< BOGUS MSG >>>"); + else { + cp1 = (char *) &cpu->ipc_buffer[11]; + cp2 = buf; + strcpy(cp2, cp1); + + while ((cp2 = strchr(cp2, '\r')) != 0) { + *cp2 = ' '; + if (cp2[1] == '\n') + cp2[1] = ' '; + } + } + + DBGS((KERN_INFO "recv_secondary_console_msg: on %d " + "message is '%s'\n", mycpu, buf)); + } + + hwrpb->txrdy = 0; +} + +/* + * Convince the console to have a secondary cpu begin execution. + */ +static int __cpuinit +secondary_cpu_start(int cpuid, struct task_struct *idle) +{ + struct percpu_struct *cpu; + struct pcb_struct *hwpcb, *ipcb; + unsigned long timeout; + + cpu = (struct percpu_struct *) + ((char*)hwrpb + + hwrpb->processor_offset + + cpuid * hwrpb->processor_size); + hwpcb = (struct pcb_struct *) cpu->hwpcb; + ipcb = &task_thread_info(idle)->pcb; + + /* Initialize the CPU's HWPCB to something just good enough for + us to get started. Immediately after starting, we'll swpctx + to the target idle task's pcb. Reuse the stack in the mean + time. Precalculate the target PCBB. */ + hwpcb->ksp = (unsigned long)ipcb + sizeof(union thread_union) - 16; + hwpcb->usp = 0; + hwpcb->ptbr = ipcb->ptbr; + hwpcb->pcc = 0; + hwpcb->asn = 0; + hwpcb->unique = virt_to_phys(ipcb); + hwpcb->flags = ipcb->flags; + hwpcb->res1 = hwpcb->res2 = 0; + +#if 0 + DBGS(("KSP 0x%lx PTBR 0x%lx VPTBR 0x%lx UNIQUE 0x%lx\n", + hwpcb->ksp, hwpcb->ptbr, hwrpb->vptb, hwpcb->unique)); +#endif + DBGS(("Starting secondary cpu %d: state 0x%lx pal_flags 0x%lx\n", + cpuid, idle->state, ipcb->flags)); + + /* Setup HWRPB fields that SRM uses to activate secondary CPU */ + hwrpb->CPU_restart = __smp_callin; + hwrpb->CPU_restart_data = (unsigned long) __smp_callin; + + /* Recalculate and update the HWRPB checksum */ + hwrpb_update_checksum(hwrpb); + + /* + * Send a "start" command to the specified processor. + */ + + /* SRM III 3.4.1.3 */ + cpu->flags |= 0x22; /* turn on Context Valid and Restart Capable */ + cpu->flags &= ~1; /* turn off Bootstrap In Progress */ + wmb(); + + send_secondary_console_msg("START\r\n", cpuid); + + /* Wait 10 seconds for an ACK from the console. */ + timeout = jiffies + 10*HZ; + while (time_before(jiffies, timeout)) { + if (cpu->flags & 1) + goto started; + udelay(10); + barrier(); + } + printk(KERN_ERR "SMP: Processor %d failed to start.\n", cpuid); + return -1; + + started: + DBGS(("secondary_cpu_start: SUCCESS for CPU %d!!!\n", cpuid)); + return 0; +} + +/* + * Bring one cpu online. + */ +static int __cpuinit +smp_boot_one_cpu(int cpuid) +{ + struct task_struct *idle; + unsigned long timeout; + + /* Cook up an idler for this guy. Note that the address we + give to kernel_thread is irrelevant -- it's going to start + where HWRPB.CPU_restart says to start. But this gets all + the other task-y sort of data structures set up like we + wish. We can't use kernel_thread since we must avoid + rescheduling the child. */ + idle = fork_idle(cpuid); + if (IS_ERR(idle)) + panic("failed fork for CPU %d", cpuid); + + DBGS(("smp_boot_one_cpu: CPU %d state 0x%lx flags 0x%lx\n", + cpuid, idle->state, idle->flags)); + + /* Signal the secondary to wait a moment. */ + smp_secondary_alive = -1; + + /* Whirrr, whirrr, whirrrrrrrrr... */ + if (secondary_cpu_start(cpuid, idle)) + return -1; + + /* Notify the secondary CPU it can run calibrate_delay. */ + mb(); + smp_secondary_alive = 0; + + /* We've been acked by the console; wait one second for + the task to start up for real. */ + timeout = jiffies + 1*HZ; + while (time_before(jiffies, timeout)) { + if (smp_secondary_alive == 1) + goto alive; + udelay(10); + barrier(); + } + + /* We failed to boot the CPU. */ + + printk(KERN_ERR "SMP: Processor %d is stuck.\n", cpuid); + return -1; + + alive: + /* Another "Red Snapper". */ + return 0; +} + +/* + * Called from setup_arch. Detect an SMP system and which processors + * are present. + */ +void __init +setup_smp(void) +{ + struct percpu_struct *cpubase, *cpu; + unsigned long i; + + if (boot_cpuid != 0) { + printk(KERN_WARNING "SMP: Booting off cpu %d instead of 0?\n", + boot_cpuid); + } + + if (hwrpb->nr_processors > 1) { + int boot_cpu_palrev; + + DBGS(("setup_smp: nr_processors %ld\n", + hwrpb->nr_processors)); + + cpubase = (struct percpu_struct *) + ((char*)hwrpb + hwrpb->processor_offset); + boot_cpu_palrev = cpubase->pal_revision; + + for (i = 0; i < hwrpb->nr_processors; i++) { + cpu = (struct percpu_struct *) + ((char *)cpubase + i*hwrpb->processor_size); + if ((cpu->flags & 0x1cc) == 0x1cc) { + smp_num_probed++; + set_cpu_possible(i, true); + set_cpu_present(i, true); + cpu->pal_revision = boot_cpu_palrev; + } + + DBGS(("setup_smp: CPU %d: flags 0x%lx type 0x%lx\n", + i, cpu->flags, cpu->type)); + DBGS(("setup_smp: CPU %d: PAL rev 0x%lx\n", + i, cpu->pal_revision)); + } + } else { + smp_num_probed = 1; + } + + printk(KERN_INFO "SMP: %d CPUs probed -- cpu_present_map = %lx\n", + smp_num_probed, cpumask_bits(cpu_present_mask)[0]); +} + +/* + * Called by smp_init prepare the secondaries + */ +void __init +smp_prepare_cpus(unsigned int max_cpus) +{ + /* Take care of some initial bookkeeping. */ + memset(ipi_data, 0, sizeof(ipi_data)); + + current_thread_info()->cpu = boot_cpuid; + + smp_store_cpu_info(boot_cpuid); + smp_setup_percpu_timer(boot_cpuid); + + /* Nothing to do on a UP box, or when told not to. */ + if (smp_num_probed == 1 || max_cpus == 0) { + init_cpu_possible(cpumask_of(boot_cpuid)); + init_cpu_present(cpumask_of(boot_cpuid)); + printk(KERN_INFO "SMP mode deactivated.\n"); + return; + } + + printk(KERN_INFO "SMP starting up secondaries.\n"); + + smp_num_cpus = smp_num_probed; +} + +void __devinit +smp_prepare_boot_cpu(void) +{ +} + +int __cpuinit +__cpu_up(unsigned int cpu) +{ + smp_boot_one_cpu(cpu); + + return cpu_online(cpu) ? 0 : -ENOSYS; +} + +void __init +smp_cpus_done(unsigned int max_cpus) +{ + int cpu; + unsigned long bogosum = 0; + + for(cpu = 0; cpu < NR_CPUS; cpu++) + if (cpu_online(cpu)) + bogosum += cpu_data[cpu].loops_per_jiffy; + + printk(KERN_INFO "SMP: Total of %d processors activated " + "(%lu.%02lu BogoMIPS).\n", + num_online_cpus(), + (bogosum + 2500) / (500000/HZ), + ((bogosum + 2500) / (5000/HZ)) % 100); +} + + +void +smp_percpu_timer_interrupt(struct pt_regs *regs) +{ + struct pt_regs *old_regs; + int cpu = smp_processor_id(); + unsigned long user = user_mode(regs); + struct cpuinfo_alpha *data = &cpu_data[cpu]; + + old_regs = set_irq_regs(regs); + + /* Record kernel PC. */ + profile_tick(CPU_PROFILING); + + if (!--data->prof_counter) { + /* We need to make like a normal interrupt -- otherwise + timer interrupts ignore the global interrupt lock, + which would be a Bad Thing. */ + irq_enter(); + + update_process_times(user); + + data->prof_counter = data->prof_multiplier; + + irq_exit(); + } + set_irq_regs(old_regs); +} + +int +setup_profiling_timer(unsigned int multiplier) +{ + return -EINVAL; +} + + +static void +send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation) +{ + int i; + + mb(); + for_each_cpu(i, to_whom) + set_bit(operation, &ipi_data[i].bits); + + mb(); + for_each_cpu(i, to_whom) + wripir(i); +} + +void +handle_ipi(struct pt_regs *regs) +{ + int this_cpu = smp_processor_id(); + unsigned long *pending_ipis = &ipi_data[this_cpu].bits; + unsigned long ops; + +#if 0 + DBGS(("handle_ipi: on CPU %d ops 0x%lx PC 0x%lx\n", + this_cpu, *pending_ipis, regs->pc)); +#endif + + mb(); /* Order interrupt and bit testing. */ + while ((ops = xchg(pending_ipis, 0)) != 0) { + mb(); /* Order bit clearing and data access. */ + do { + unsigned long which; + + which = ops & -ops; + ops &= ~which; + which = __ffs(which); + + switch (which) { + case IPI_RESCHEDULE: + scheduler_ipi(); + break; + + case IPI_CALL_FUNC: + generic_smp_call_function_interrupt(); + break; + + case IPI_CALL_FUNC_SINGLE: + generic_smp_call_function_single_interrupt(); + break; + + case IPI_CPU_STOP: + halt(); + + default: + printk(KERN_CRIT "Unknown IPI on CPU %d: %lu\n", + this_cpu, which); + break; + } + } while (ops); + + mb(); /* Order data access and bit testing. */ + } + + cpu_data[this_cpu].ipi_count++; + + if (hwrpb->txrdy) + recv_secondary_console_msg(); +} + +void +smp_send_reschedule(int cpu) +{ +#ifdef DEBUG_IPI_MSG + if (cpu == hard_smp_processor_id()) + printk(KERN_WARNING + "smp_send_reschedule: Sending IPI to self.\n"); +#endif + send_ipi_message(cpumask_of(cpu), IPI_RESCHEDULE); +} + +void +smp_send_stop(void) +{ + cpumask_t to_whom; + cpumask_copy(&to_whom, cpu_possible_mask); + cpumask_clear_cpu(smp_processor_id(), &to_whom); +#ifdef DEBUG_IPI_MSG + if (hard_smp_processor_id() != boot_cpu_id) + printk(KERN_WARNING "smp_send_stop: Not on boot cpu.\n"); +#endif + send_ipi_message(&to_whom, IPI_CPU_STOP); +} + +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + send_ipi_message(mask, IPI_CALL_FUNC); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); +} + +static void +ipi_imb(void *ignored) +{ + imb(); +} + +void +smp_imb(void) +{ + /* Must wait other processors to flush their icache before continue. */ + if (on_each_cpu(ipi_imb, NULL, 1)) + printk(KERN_CRIT "smp_imb: timed out\n"); +} +EXPORT_SYMBOL(smp_imb); + +static void +ipi_flush_tlb_all(void *ignored) +{ + tbia(); +} + +void +flush_tlb_all(void) +{ + /* Although we don't have any data to pass, we do want to + synchronize with the other processors. */ + if (on_each_cpu(ipi_flush_tlb_all, NULL, 1)) { + printk(KERN_CRIT "flush_tlb_all: timed out\n"); + } +} + +#define asn_locked() (cpu_data[smp_processor_id()].asn_lock) + +static void +ipi_flush_tlb_mm(void *x) +{ + struct mm_struct *mm = (struct mm_struct *) x; + if (mm == current->active_mm && !asn_locked()) + flush_tlb_current(mm); + else + flush_tlb_other(mm); +} + +void +flush_tlb_mm(struct mm_struct *mm) +{ + preempt_disable(); + + if (mm == current->active_mm) { + flush_tlb_current(mm); + if (atomic_read(&mm->mm_users) <= 1) { + int cpu, this_cpu = smp_processor_id(); + for (cpu = 0; cpu < NR_CPUS; cpu++) { + if (!cpu_online(cpu) || cpu == this_cpu) + continue; + if (mm->context[cpu]) + mm->context[cpu] = 0; + } + preempt_enable(); + return; + } + } + + if (smp_call_function(ipi_flush_tlb_mm, mm, 1)) { + printk(KERN_CRIT "flush_tlb_mm: timed out\n"); + } + + preempt_enable(); +} +EXPORT_SYMBOL(flush_tlb_mm); + +struct flush_tlb_page_struct { + struct vm_area_struct *vma; + struct mm_struct *mm; + unsigned long addr; +}; + +static void +ipi_flush_tlb_page(void *x) +{ + struct flush_tlb_page_struct *data = (struct flush_tlb_page_struct *)x; + struct mm_struct * mm = data->mm; + + if (mm == current->active_mm && !asn_locked()) + flush_tlb_current_page(mm, data->vma, data->addr); + else + flush_tlb_other(mm); +} + +void +flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) +{ + struct flush_tlb_page_struct data; + struct mm_struct *mm = vma->vm_mm; + + preempt_disable(); + + if (mm == current->active_mm) { + flush_tlb_current_page(mm, vma, addr); + if (atomic_read(&mm->mm_users) <= 1) { + int cpu, this_cpu = smp_processor_id(); + for (cpu = 0; cpu < NR_CPUS; cpu++) { + if (!cpu_online(cpu) || cpu == this_cpu) + continue; + if (mm->context[cpu]) + mm->context[cpu] = 0; + } + preempt_enable(); + return; + } + } + + data.vma = vma; + data.mm = mm; + data.addr = addr; + + if (smp_call_function(ipi_flush_tlb_page, &data, 1)) { + printk(KERN_CRIT "flush_tlb_page: timed out\n"); + } + + preempt_enable(); +} +EXPORT_SYMBOL(flush_tlb_page); + +void +flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) +{ + /* On the Alpha we always flush the whole user tlb. */ + flush_tlb_mm(vma->vm_mm); +} +EXPORT_SYMBOL(flush_tlb_range); + +static void +ipi_flush_icache_page(void *x) +{ + struct mm_struct *mm = (struct mm_struct *) x; + if (mm == current->active_mm && !asn_locked()) + __load_new_mm_context(mm); + else + flush_tlb_other(mm); +} + +void +flush_icache_user_range(struct vm_area_struct *vma, struct page *page, + unsigned long addr, int len) +{ + struct mm_struct *mm = vma->vm_mm; + + if ((vma->vm_flags & VM_EXEC) == 0) + return; + + preempt_disable(); + + if (mm == current->active_mm) { + __load_new_mm_context(mm); + if (atomic_read(&mm->mm_users) <= 1) { + int cpu, this_cpu = smp_processor_id(); + for (cpu = 0; cpu < NR_CPUS; cpu++) { + if (!cpu_online(cpu) || cpu == this_cpu) + continue; + if (mm->context[cpu]) + mm->context[cpu] = 0; + } + preempt_enable(); + return; + } + } + + if (smp_call_function(ipi_flush_icache_page, mm, 1)) { + printk(KERN_CRIT "flush_icache_page: timed out\n"); + } + + preempt_enable(); +} -- cgit v1.2.3