1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
1164 lines
26 KiB
C
1164 lines
26 KiB
C
/*
|
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* linux/arch/alpha/kernel/smp.c
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*
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* 2001-07-09 Phil Ezolt (Phillip.Ezolt@compaq.com)
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* Renamed modified smp_call_function to smp_call_function_on_cpu()
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* Created an function that conforms to the old calling convention
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* of smp_call_function().
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*
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* This is helpful for DCPI.
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*
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*/
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/kernel_stat.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/threads.h>
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#include <linux/smp.h>
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#include <linux/smp_lock.h>
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#include <linux/interrupt.h>
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#include <linux/init.h>
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#include <linux/delay.h>
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#include <linux/spinlock.h>
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#include <linux/irq.h>
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#include <linux/cache.h>
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#include <linux/profile.h>
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#include <linux/bitops.h>
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|
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#include <asm/hwrpb.h>
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#include <asm/ptrace.h>
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#include <asm/atomic.h>
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#include <asm/io.h>
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#include <asm/irq.h>
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#include <asm/pgtable.h>
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#include <asm/pgalloc.h>
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#include <asm/mmu_context.h>
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#include <asm/tlbflush.h>
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#include "proto.h"
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#include "irq_impl.h"
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#define DEBUG_SMP 0
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#if DEBUG_SMP
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#define DBGS(args) printk args
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#else
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#define DBGS(args)
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#endif
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/* A collection of per-processor data. */
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struct cpuinfo_alpha cpu_data[NR_CPUS];
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/* A collection of single bit ipi messages. */
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static struct {
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unsigned long bits ____cacheline_aligned;
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} ipi_data[NR_CPUS] __cacheline_aligned;
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enum ipi_message_type {
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IPI_RESCHEDULE,
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IPI_CALL_FUNC,
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IPI_CPU_STOP,
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};
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/* Set to a secondary's cpuid when it comes online. */
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static int smp_secondary_alive __initdata = 0;
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/* Which cpus ids came online. */
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cpumask_t cpu_present_mask;
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cpumask_t cpu_online_map;
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EXPORT_SYMBOL(cpu_online_map);
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/* cpus reported in the hwrpb */
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static unsigned long hwrpb_cpu_present_mask __initdata = 0;
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int smp_num_probed; /* Internal processor count */
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int smp_num_cpus = 1; /* Number that came online. */
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extern void calibrate_delay(void);
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/*
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* Called by both boot and secondaries to move global data into
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* per-processor storage.
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*/
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static inline void __init
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smp_store_cpu_info(int cpuid)
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{
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cpu_data[cpuid].loops_per_jiffy = loops_per_jiffy;
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cpu_data[cpuid].last_asn = ASN_FIRST_VERSION;
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cpu_data[cpuid].need_new_asn = 0;
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cpu_data[cpuid].asn_lock = 0;
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}
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/*
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* Ideally sets up per-cpu profiling hooks. Doesn't do much now...
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*/
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static inline void __init
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smp_setup_percpu_timer(int cpuid)
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{
|
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cpu_data[cpuid].prof_counter = 1;
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cpu_data[cpuid].prof_multiplier = 1;
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}
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|
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static void __init
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wait_boot_cpu_to_stop(int cpuid)
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{
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unsigned long stop = jiffies + 10*HZ;
|
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|
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while (time_before(jiffies, stop)) {
|
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if (!smp_secondary_alive)
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return;
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barrier();
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}
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||
|
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printk("wait_boot_cpu_to_stop: FAILED on CPU %d, hanging now\n", cpuid);
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for (;;)
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barrier();
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}
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/*
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* Where secondaries begin a life of C.
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*/
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void __init
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smp_callin(void)
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{
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int cpuid = hard_smp_processor_id();
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|
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if (cpu_test_and_set(cpuid, cpu_online_map)) {
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printk("??, cpu 0x%x already present??\n", cpuid);
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BUG();
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}
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/* Turn on machine checks. */
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wrmces(7);
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/* Set trap vectors. */
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trap_init();
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/* Set interrupt vector. */
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wrent(entInt, 0);
|
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|
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/* Get our local ticker going. */
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smp_setup_percpu_timer(cpuid);
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/* Call platform-specific callin, if specified */
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if (alpha_mv.smp_callin) alpha_mv.smp_callin();
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/* All kernel threads share the same mm context. */
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atomic_inc(&init_mm.mm_count);
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current->active_mm = &init_mm;
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/* Must have completely accurate bogos. */
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local_irq_enable();
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/* Wait boot CPU to stop with irq enabled before running
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calibrate_delay. */
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wait_boot_cpu_to_stop(cpuid);
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mb();
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calibrate_delay();
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smp_store_cpu_info(cpuid);
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/* Allow master to continue only after we written loops_per_jiffy. */
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wmb();
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smp_secondary_alive = 1;
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DBGS(("smp_callin: commencing CPU %d current %p active_mm %p\n",
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cpuid, current, current->active_mm));
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/* Do nothing. */
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cpu_idle();
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}
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/* Wait until hwrpb->txrdy is clear for cpu. Return -1 on timeout. */
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static int __init
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wait_for_txrdy (unsigned long cpumask)
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{
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unsigned long timeout;
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if (!(hwrpb->txrdy & cpumask))
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return 0;
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timeout = jiffies + 10*HZ;
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while (time_before(jiffies, timeout)) {
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if (!(hwrpb->txrdy & cpumask))
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return 0;
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udelay(10);
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barrier();
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}
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return -1;
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}
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/*
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* Send a message to a secondary's console. "START" is one such
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* interesting message. ;-)
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*/
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static void __init
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send_secondary_console_msg(char *str, int cpuid)
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{
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struct percpu_struct *cpu;
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register char *cp1, *cp2;
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unsigned long cpumask;
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size_t len;
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cpu = (struct percpu_struct *)
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((char*)hwrpb
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+ hwrpb->processor_offset
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+ cpuid * hwrpb->processor_size);
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cpumask = (1UL << cpuid);
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if (wait_for_txrdy(cpumask))
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goto timeout;
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cp2 = str;
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len = strlen(cp2);
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*(unsigned int *)&cpu->ipc_buffer[0] = len;
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cp1 = (char *) &cpu->ipc_buffer[1];
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memcpy(cp1, cp2, len);
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/* atomic test and set */
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wmb();
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set_bit(cpuid, &hwrpb->rxrdy);
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if (wait_for_txrdy(cpumask))
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goto timeout;
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return;
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timeout:
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printk("Processor %x not ready\n", cpuid);
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}
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/*
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* A secondary console wants to send a message. Receive it.
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*/
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static void
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recv_secondary_console_msg(void)
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{
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int mycpu, i, cnt;
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unsigned long txrdy = hwrpb->txrdy;
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char *cp1, *cp2, buf[80];
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struct percpu_struct *cpu;
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DBGS(("recv_secondary_console_msg: TXRDY 0x%lx.\n", txrdy));
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mycpu = hard_smp_processor_id();
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for (i = 0; i < NR_CPUS; i++) {
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if (!(txrdy & (1UL << i)))
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continue;
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DBGS(("recv_secondary_console_msg: "
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"TXRDY contains CPU %d.\n", i));
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cpu = (struct percpu_struct *)
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((char*)hwrpb
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+ hwrpb->processor_offset
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+ i * hwrpb->processor_size);
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DBGS(("recv_secondary_console_msg: on %d from %d"
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" HALT_REASON 0x%lx FLAGS 0x%lx\n",
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mycpu, i, cpu->halt_reason, cpu->flags));
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cnt = cpu->ipc_buffer[0] >> 32;
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if (cnt <= 0 || cnt >= 80)
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strcpy(buf, "<<< BOGUS MSG >>>");
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else {
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cp1 = (char *) &cpu->ipc_buffer[11];
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cp2 = buf;
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strcpy(cp2, cp1);
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while ((cp2 = strchr(cp2, '\r')) != 0) {
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*cp2 = ' ';
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if (cp2[1] == '\n')
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cp2[1] = ' ';
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}
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}
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DBGS((KERN_INFO "recv_secondary_console_msg: on %d "
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"message is '%s'\n", mycpu, buf));
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}
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hwrpb->txrdy = 0;
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}
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/*
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* Convince the console to have a secondary cpu begin execution.
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*/
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static int __init
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secondary_cpu_start(int cpuid, struct task_struct *idle)
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{
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struct percpu_struct *cpu;
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struct pcb_struct *hwpcb, *ipcb;
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unsigned long timeout;
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cpu = (struct percpu_struct *)
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((char*)hwrpb
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+ hwrpb->processor_offset
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+ cpuid * hwrpb->processor_size);
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hwpcb = (struct pcb_struct *) cpu->hwpcb;
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ipcb = &idle->thread_info->pcb;
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/* Initialize the CPU's HWPCB to something just good enough for
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us to get started. Immediately after starting, we'll swpctx
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to the target idle task's pcb. Reuse the stack in the mean
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time. Precalculate the target PCBB. */
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hwpcb->ksp = (unsigned long)ipcb + sizeof(union thread_union) - 16;
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hwpcb->usp = 0;
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hwpcb->ptbr = ipcb->ptbr;
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hwpcb->pcc = 0;
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hwpcb->asn = 0;
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hwpcb->unique = virt_to_phys(ipcb);
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hwpcb->flags = ipcb->flags;
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hwpcb->res1 = hwpcb->res2 = 0;
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#if 0
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DBGS(("KSP 0x%lx PTBR 0x%lx VPTBR 0x%lx UNIQUE 0x%lx\n",
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hwpcb->ksp, hwpcb->ptbr, hwrpb->vptb, hwpcb->unique));
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#endif
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DBGS(("Starting secondary cpu %d: state 0x%lx pal_flags 0x%lx\n",
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cpuid, idle->state, ipcb->flags));
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|
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/* Setup HWRPB fields that SRM uses to activate secondary CPU */
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hwrpb->CPU_restart = __smp_callin;
|
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hwrpb->CPU_restart_data = (unsigned long) __smp_callin;
|
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|
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/* Recalculate and update the HWRPB checksum */
|
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hwrpb_update_checksum(hwrpb);
|
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|
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/*
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* Send a "start" command to the specified processor.
|
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*/
|
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|
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/* SRM III 3.4.1.3 */
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cpu->flags |= 0x22; /* turn on Context Valid and Restart Capable */
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cpu->flags &= ~1; /* turn off Bootstrap In Progress */
|
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wmb();
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send_secondary_console_msg("START\r\n", cpuid);
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/* Wait 10 seconds for an ACK from the console. */
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timeout = jiffies + 10*HZ;
|
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while (time_before(jiffies, timeout)) {
|
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if (cpu->flags & 1)
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goto started;
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udelay(10);
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barrier();
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}
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printk(KERN_ERR "SMP: Processor %d failed to start.\n", cpuid);
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return -1;
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started:
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DBGS(("secondary_cpu_start: SUCCESS for CPU %d!!!\n", cpuid));
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return 0;
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}
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|
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/*
|
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* Bring one cpu online.
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*/
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static int __init
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smp_boot_one_cpu(int cpuid)
|
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{
|
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struct task_struct *idle;
|
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unsigned long timeout;
|
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|
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/* Cook up an idler for this guy. Note that the address we
|
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give to kernel_thread is irrelevant -- it's going to start
|
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where HWRPB.CPU_restart says to start. But this gets all
|
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the other task-y sort of data structures set up like we
|
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wish. We can't use kernel_thread since we must avoid
|
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rescheduling the child. */
|
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idle = fork_idle(cpuid);
|
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if (IS_ERR(idle))
|
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panic("failed fork for CPU %d", cpuid);
|
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|
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DBGS(("smp_boot_one_cpu: CPU %d state 0x%lx flags 0x%lx\n",
|
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cpuid, idle->state, idle->flags));
|
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|
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/* Signal the secondary to wait a moment. */
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smp_secondary_alive = -1;
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|
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/* Whirrr, whirrr, whirrrrrrrrr... */
|
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if (secondary_cpu_start(cpuid, idle))
|
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return -1;
|
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|
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/* Notify the secondary CPU it can run calibrate_delay. */
|
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mb();
|
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smp_secondary_alive = 0;
|
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|
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/* We've been acked by the console; wait one second for
|
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the task to start up for real. */
|
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timeout = jiffies + 1*HZ;
|
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while (time_before(jiffies, timeout)) {
|
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if (smp_secondary_alive == 1)
|
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goto alive;
|
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udelay(10);
|
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barrier();
|
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}
|
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|
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/* We failed to boot the CPU. */
|
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|
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printk(KERN_ERR "SMP: Processor %d is stuck.\n", cpuid);
|
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return -1;
|
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|
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alive:
|
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/* Another "Red Snapper". */
|
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return 0;
|
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}
|
||
|
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/*
|
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* Called from setup_arch. Detect an SMP system and which processors
|
||
* are present.
|
||
*/
|
||
void __init
|
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setup_smp(void)
|
||
{
|
||
struct percpu_struct *cpubase, *cpu;
|
||
unsigned long i;
|
||
|
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if (boot_cpuid != 0) {
|
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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 *)
|
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((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++;
|
||
/* Assume here that "whami" == index */
|
||
hwrpb_cpu_present_mask |= (1UL << i);
|
||
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;
|
||
hwrpb_cpu_present_mask = (1UL << boot_cpuid);
|
||
}
|
||
cpu_present_mask = cpumask_of_cpu(boot_cpuid);
|
||
|
||
printk(KERN_INFO "SMP: %d CPUs probed -- cpu_present_mask = %lx\n",
|
||
smp_num_probed, hwrpb_cpu_present_mask);
|
||
}
|
||
|
||
/*
|
||
* Called by smp_init prepare the secondaries
|
||
*/
|
||
void __init
|
||
smp_prepare_cpus(unsigned int max_cpus)
|
||
{
|
||
int cpu_count, i;
|
||
|
||
/* 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) {
|
||
cpu_present_mask = cpumask_of_cpu(boot_cpuid);
|
||
printk(KERN_INFO "SMP mode deactivated.\n");
|
||
return;
|
||
}
|
||
|
||
printk(KERN_INFO "SMP starting up secondaries.\n");
|
||
|
||
cpu_count = 1;
|
||
for (i = 0; (i < NR_CPUS) && (cpu_count < max_cpus); i++) {
|
||
if (i == boot_cpuid)
|
||
continue;
|
||
|
||
if (((hwrpb_cpu_present_mask >> i) & 1) == 0)
|
||
continue;
|
||
|
||
cpu_set(i, cpu_possible_map);
|
||
cpu_count++;
|
||
}
|
||
|
||
smp_num_cpus = cpu_count;
|
||
}
|
||
|
||
void __devinit
|
||
smp_prepare_boot_cpu(void)
|
||
{
|
||
/*
|
||
* Mark the boot cpu (current cpu) as both present and online
|
||
*/
|
||
cpu_set(smp_processor_id(), cpu_present_mask);
|
||
cpu_set(smp_processor_id(), cpu_online_map);
|
||
}
|
||
|
||
int __devinit
|
||
__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)
|
||
{
|
||
int cpu = smp_processor_id();
|
||
unsigned long user = user_mode(regs);
|
||
struct cpuinfo_alpha *data = &cpu_data[cpu];
|
||
|
||
/* Record kernel PC. */
|
||
profile_tick(CPU_PROFILING, regs);
|
||
|
||
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();
|
||
}
|
||
}
|
||
|
||
int __init
|
||
setup_profiling_timer(unsigned int multiplier)
|
||
{
|
||
return -EINVAL;
|
||
}
|
||
|
||
|
||
static void
|
||
send_ipi_message(cpumask_t to_whom, enum ipi_message_type operation)
|
||
{
|
||
int i;
|
||
|
||
mb();
|
||
for_each_cpu_mask(i, to_whom)
|
||
set_bit(operation, &ipi_data[i].bits);
|
||
|
||
mb();
|
||
for_each_cpu_mask(i, to_whom)
|
||
wripir(i);
|
||
}
|
||
|
||
/* Structure and data for smp_call_function. This is designed to
|
||
minimize static memory requirements. Plus it looks cleaner. */
|
||
|
||
struct smp_call_struct {
|
||
void (*func) (void *info);
|
||
void *info;
|
||
long wait;
|
||
atomic_t unstarted_count;
|
||
atomic_t unfinished_count;
|
||
};
|
||
|
||
static struct smp_call_struct *smp_call_function_data;
|
||
|
||
/* Atomicly drop data into a shared pointer. The pointer is free if
|
||
it is initially locked. If retry, spin until free. */
|
||
|
||
static int
|
||
pointer_lock (void *lock, void *data, int retry)
|
||
{
|
||
void *old, *tmp;
|
||
|
||
mb();
|
||
again:
|
||
/* Compare and swap with zero. */
|
||
asm volatile (
|
||
"1: ldq_l %0,%1\n"
|
||
" mov %3,%2\n"
|
||
" bne %0,2f\n"
|
||
" stq_c %2,%1\n"
|
||
" beq %2,1b\n"
|
||
"2:"
|
||
: "=&r"(old), "=m"(*(void **)lock), "=&r"(tmp)
|
||
: "r"(data)
|
||
: "memory");
|
||
|
||
if (old == 0)
|
||
return 0;
|
||
if (! retry)
|
||
return -EBUSY;
|
||
|
||
while (*(void **)lock)
|
||
barrier();
|
||
goto again;
|
||
}
|
||
|
||
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:
|
||
/* Reschedule callback. Everything to be done
|
||
is done by the interrupt return path. */
|
||
break;
|
||
|
||
case IPI_CALL_FUNC:
|
||
{
|
||
struct smp_call_struct *data;
|
||
void (*func)(void *info);
|
||
void *info;
|
||
int wait;
|
||
|
||
data = smp_call_function_data;
|
||
func = data->func;
|
||
info = data->info;
|
||
wait = data->wait;
|
||
|
||
/* Notify the sending CPU that the data has been
|
||
received, and execution is about to begin. */
|
||
mb();
|
||
atomic_dec (&data->unstarted_count);
|
||
|
||
/* At this point the structure may be gone unless
|
||
wait is true. */
|
||
(*func)(info);
|
||
|
||
/* Notify the sending CPU that the task is done. */
|
||
mb();
|
||
if (wait) atomic_dec (&data->unfinished_count);
|
||
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(cpu), IPI_RESCHEDULE);
|
||
}
|
||
|
||
void
|
||
smp_send_stop(void)
|
||
{
|
||
cpumask_t to_whom = cpu_possible_map;
|
||
cpu_clear(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);
|
||
}
|
||
|
||
/*
|
||
* Run a function on all other CPUs.
|
||
* <func> The function to run. This must be fast and non-blocking.
|
||
* <info> An arbitrary pointer to pass to the function.
|
||
* <retry> If true, keep retrying until ready.
|
||
* <wait> If true, wait until function has completed on other CPUs.
|
||
* [RETURNS] 0 on success, else a negative status code.
|
||
*
|
||
* Does not return until remote CPUs are nearly ready to execute <func>
|
||
* or are or have executed.
|
||
* You must not call this function with disabled interrupts or from a
|
||
* hardware interrupt handler or from a bottom half handler.
|
||
*/
|
||
|
||
int
|
||
smp_call_function_on_cpu (void (*func) (void *info), void *info, int retry,
|
||
int wait, cpumask_t to_whom)
|
||
{
|
||
struct smp_call_struct data;
|
||
unsigned long timeout;
|
||
int num_cpus_to_call;
|
||
|
||
/* Can deadlock when called with interrupts disabled */
|
||
WARN_ON(irqs_disabled());
|
||
|
||
data.func = func;
|
||
data.info = info;
|
||
data.wait = wait;
|
||
|
||
cpu_clear(smp_processor_id(), to_whom);
|
||
num_cpus_to_call = cpus_weight(to_whom);
|
||
|
||
atomic_set(&data.unstarted_count, num_cpus_to_call);
|
||
atomic_set(&data.unfinished_count, num_cpus_to_call);
|
||
|
||
/* Acquire the smp_call_function_data mutex. */
|
||
if (pointer_lock(&smp_call_function_data, &data, retry))
|
||
return -EBUSY;
|
||
|
||
/* Send a message to the requested CPUs. */
|
||
send_ipi_message(to_whom, IPI_CALL_FUNC);
|
||
|
||
/* Wait for a minimal response. */
|
||
timeout = jiffies + HZ;
|
||
while (atomic_read (&data.unstarted_count) > 0
|
||
&& time_before (jiffies, timeout))
|
||
barrier();
|
||
|
||
/* If there's no response yet, log a message but allow a longer
|
||
* timeout period -- if we get a response this time, log
|
||
* a message saying when we got it..
|
||
*/
|
||
if (atomic_read(&data.unstarted_count) > 0) {
|
||
long start_time = jiffies;
|
||
printk(KERN_ERR "%s: initial timeout -- trying long wait\n",
|
||
__FUNCTION__);
|
||
timeout = jiffies + 30 * HZ;
|
||
while (atomic_read(&data.unstarted_count) > 0
|
||
&& time_before(jiffies, timeout))
|
||
barrier();
|
||
if (atomic_read(&data.unstarted_count) <= 0) {
|
||
long delta = jiffies - start_time;
|
||
printk(KERN_ERR
|
||
"%s: response %ld.%ld seconds into long wait\n",
|
||
__FUNCTION__, delta / HZ,
|
||
(100 * (delta - ((delta / HZ) * HZ))) / HZ);
|
||
}
|
||
}
|
||
|
||
/* We either got one or timed out -- clear the lock. */
|
||
mb();
|
||
smp_call_function_data = NULL;
|
||
|
||
/*
|
||
* If after both the initial and long timeout periods we still don't
|
||
* have a response, something is very wrong...
|
||
*/
|
||
BUG_ON(atomic_read (&data.unstarted_count) > 0);
|
||
|
||
/* Wait for a complete response, if needed. */
|
||
if (wait) {
|
||
while (atomic_read (&data.unfinished_count) > 0)
|
||
barrier();
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
int
|
||
smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
|
||
{
|
||
return smp_call_function_on_cpu (func, info, retry, wait,
|
||
cpu_online_map);
|
||
}
|
||
|
||
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, 1))
|
||
printk(KERN_CRIT "smp_imb: timed out\n");
|
||
}
|
||
|
||
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, 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, 1)) {
|
||
printk(KERN_CRIT "flush_tlb_mm: timed out\n");
|
||
}
|
||
|
||
preempt_enable();
|
||
}
|
||
|
||
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, 1)) {
|
||
printk(KERN_CRIT "flush_tlb_page: timed out\n");
|
||
}
|
||
|
||
preempt_enable();
|
||
}
|
||
|
||
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);
|
||
}
|
||
|
||
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, 1)) {
|
||
printk(KERN_CRIT "flush_icache_page: timed out\n");
|
||
}
|
||
|
||
preempt_enable();
|
||
}
|
||
|
||
#ifdef CONFIG_DEBUG_SPINLOCK
|
||
void
|
||
_raw_spin_unlock(spinlock_t * lock)
|
||
{
|
||
mb();
|
||
lock->lock = 0;
|
||
|
||
lock->on_cpu = -1;
|
||
lock->previous = NULL;
|
||
lock->task = NULL;
|
||
lock->base_file = "none";
|
||
lock->line_no = 0;
|
||
}
|
||
|
||
void
|
||
debug_spin_lock(spinlock_t * lock, const char *base_file, int line_no)
|
||
{
|
||
long tmp;
|
||
long stuck;
|
||
void *inline_pc = __builtin_return_address(0);
|
||
unsigned long started = jiffies;
|
||
int printed = 0;
|
||
int cpu = smp_processor_id();
|
||
|
||
stuck = 1L << 30;
|
||
try_again:
|
||
|
||
/* Use sub-sections to put the actual loop at the end
|
||
of this object file's text section so as to perfect
|
||
branch prediction. */
|
||
__asm__ __volatile__(
|
||
"1: ldl_l %0,%1\n"
|
||
" subq %2,1,%2\n"
|
||
" blbs %0,2f\n"
|
||
" or %0,1,%0\n"
|
||
" stl_c %0,%1\n"
|
||
" beq %0,3f\n"
|
||
"4: mb\n"
|
||
".subsection 2\n"
|
||
"2: ldl %0,%1\n"
|
||
" subq %2,1,%2\n"
|
||
"3: blt %2,4b\n"
|
||
" blbs %0,2b\n"
|
||
" br 1b\n"
|
||
".previous"
|
||
: "=r" (tmp), "=m" (lock->lock), "=r" (stuck)
|
||
: "1" (lock->lock), "2" (stuck) : "memory");
|
||
|
||
if (stuck < 0) {
|
||
printk(KERN_WARNING
|
||
"%s:%d spinlock stuck in %s at %p(%d)"
|
||
" owner %s at %p(%d) %s:%d\n",
|
||
base_file, line_no,
|
||
current->comm, inline_pc, cpu,
|
||
lock->task->comm, lock->previous,
|
||
lock->on_cpu, lock->base_file, lock->line_no);
|
||
stuck = 1L << 36;
|
||
printed = 1;
|
||
goto try_again;
|
||
}
|
||
|
||
/* Exiting. Got the lock. */
|
||
lock->on_cpu = cpu;
|
||
lock->previous = inline_pc;
|
||
lock->task = current;
|
||
lock->base_file = base_file;
|
||
lock->line_no = line_no;
|
||
|
||
if (printed) {
|
||
printk(KERN_WARNING
|
||
"%s:%d spinlock grabbed in %s at %p(%d) %ld ticks\n",
|
||
base_file, line_no, current->comm, inline_pc,
|
||
cpu, jiffies - started);
|
||
}
|
||
}
|
||
|
||
int
|
||
debug_spin_trylock(spinlock_t * lock, const char *base_file, int line_no)
|
||
{
|
||
int ret;
|
||
if ((ret = !test_and_set_bit(0, lock))) {
|
||
lock->on_cpu = smp_processor_id();
|
||
lock->previous = __builtin_return_address(0);
|
||
lock->task = current;
|
||
} else {
|
||
lock->base_file = base_file;
|
||
lock->line_no = line_no;
|
||
}
|
||
return ret;
|
||
}
|
||
#endif /* CONFIG_DEBUG_SPINLOCK */
|
||
|
||
#ifdef CONFIG_DEBUG_RWLOCK
|
||
void _raw_write_lock(rwlock_t * lock)
|
||
{
|
||
long regx, regy;
|
||
int stuck_lock, stuck_reader;
|
||
void *inline_pc = __builtin_return_address(0);
|
||
|
||
try_again:
|
||
|
||
stuck_lock = 1<<30;
|
||
stuck_reader = 1<<30;
|
||
|
||
__asm__ __volatile__(
|
||
"1: ldl_l %1,%0\n"
|
||
" blbs %1,6f\n"
|
||
" blt %1,8f\n"
|
||
" mov 1,%1\n"
|
||
" stl_c %1,%0\n"
|
||
" beq %1,6f\n"
|
||
"4: mb\n"
|
||
".subsection 2\n"
|
||
"6: blt %3,4b # debug\n"
|
||
" subl %3,1,%3 # debug\n"
|
||
" ldl %1,%0\n"
|
||
" blbs %1,6b\n"
|
||
"8: blt %4,4b # debug\n"
|
||
" subl %4,1,%4 # debug\n"
|
||
" ldl %1,%0\n"
|
||
" blt %1,8b\n"
|
||
" br 1b\n"
|
||
".previous"
|
||
: "=m" (*(volatile int *)lock), "=&r" (regx), "=&r" (regy),
|
||
"=&r" (stuck_lock), "=&r" (stuck_reader)
|
||
: "0" (*(volatile int *)lock), "3" (stuck_lock), "4" (stuck_reader) : "memory");
|
||
|
||
if (stuck_lock < 0) {
|
||
printk(KERN_WARNING "write_lock stuck at %p\n", inline_pc);
|
||
goto try_again;
|
||
}
|
||
if (stuck_reader < 0) {
|
||
printk(KERN_WARNING "write_lock stuck on readers at %p\n",
|
||
inline_pc);
|
||
goto try_again;
|
||
}
|
||
}
|
||
|
||
void _raw_read_lock(rwlock_t * lock)
|
||
{
|
||
long regx;
|
||
int stuck_lock;
|
||
void *inline_pc = __builtin_return_address(0);
|
||
|
||
try_again:
|
||
|
||
stuck_lock = 1<<30;
|
||
|
||
__asm__ __volatile__(
|
||
"1: ldl_l %1,%0;"
|
||
" blbs %1,6f;"
|
||
" subl %1,2,%1;"
|
||
" stl_c %1,%0;"
|
||
" beq %1,6f;"
|
||
"4: mb\n"
|
||
".subsection 2\n"
|
||
"6: ldl %1,%0;"
|
||
" blt %2,4b # debug\n"
|
||
" subl %2,1,%2 # debug\n"
|
||
" blbs %1,6b;"
|
||
" br 1b\n"
|
||
".previous"
|
||
: "=m" (*(volatile int *)lock), "=&r" (regx), "=&r" (stuck_lock)
|
||
: "0" (*(volatile int *)lock), "2" (stuck_lock) : "memory");
|
||
|
||
if (stuck_lock < 0) {
|
||
printk(KERN_WARNING "read_lock stuck at %p\n", inline_pc);
|
||
goto try_again;
|
||
}
|
||
}
|
||
#endif /* CONFIG_DEBUG_RWLOCK */
|