diff options
Diffstat (limited to 'arch/x86_64/kernel/smp.c')
| -rw-r--r-- | arch/x86_64/kernel/smp.c | 449 |
1 files changed, 0 insertions, 449 deletions
diff --git a/arch/x86_64/kernel/smp.c b/arch/x86_64/kernel/smp.c deleted file mode 100644 index 6ee74db5230..00000000000 --- a/arch/x86_64/kernel/smp.c +++ /dev/null @@ -1,449 +0,0 @@ -/* - * Intel SMP support routines. - * - * (c) 1995 Alan Cox, Building #3 <alan@redhat.com> - * (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com> - * (c) 2002,2003 Andi Kleen, SuSE Labs. - * - * This code is released under the GNU General Public License version 2 or - * later. - */ - -#include <linux/init.h> - -#include <linux/mm.h> -#include <linux/irq.h> -#include <linux/delay.h> -#include <linux/spinlock.h> -#include <linux/smp_lock.h> -#include <linux/smp.h> -#include <linux/kernel_stat.h> -#include <linux/mc146818rtc.h> -#include <linux/interrupt.h> - -#include <asm/mtrr.h> -#include <asm/pgalloc.h> -#include <asm/tlbflush.h> -#include <asm/mach_apic.h> -#include <asm/mmu_context.h> -#include <asm/proto.h> -#include <asm/apicdef.h> - -/* - * Smarter SMP flushing macros. - * c/o Linus Torvalds. - * - * These mean you can really definitely utterly forget about - * writing to user space from interrupts. (Its not allowed anyway). - * - * Optimizations Manfred Spraul <manfred@colorfullife.com> - */ - -static cpumask_t flush_cpumask; -static struct mm_struct * flush_mm; -static unsigned long flush_va; -static DEFINE_SPINLOCK(tlbstate_lock); -#define FLUSH_ALL -1ULL - -/* - * We cannot call mmdrop() because we are in interrupt context, - * instead update mm->cpu_vm_mask. - */ -static inline void leave_mm (unsigned long cpu) -{ - if (read_pda(mmu_state) == TLBSTATE_OK) - BUG(); - clear_bit(cpu, &read_pda(active_mm)->cpu_vm_mask); - load_cr3(swapper_pg_dir); -} - -/* - * - * The flush IPI assumes that a thread switch happens in this order: - * [cpu0: the cpu that switches] - * 1) switch_mm() either 1a) or 1b) - * 1a) thread switch to a different mm - * 1a1) clear_bit(cpu, &old_mm->cpu_vm_mask); - * Stop ipi delivery for the old mm. This is not synchronized with - * the other cpus, but smp_invalidate_interrupt ignore flush ipis - * for the wrong mm, and in the worst case we perform a superfluous - * tlb flush. - * 1a2) set cpu mmu_state to TLBSTATE_OK - * Now the smp_invalidate_interrupt won't call leave_mm if cpu0 - * was in lazy tlb mode. - * 1a3) update cpu active_mm - * Now cpu0 accepts tlb flushes for the new mm. - * 1a4) set_bit(cpu, &new_mm->cpu_vm_mask); - * Now the other cpus will send tlb flush ipis. - * 1a4) change cr3. - * 1b) thread switch without mm change - * cpu active_mm is correct, cpu0 already handles - * flush ipis. - * 1b1) set cpu mmu_state to TLBSTATE_OK - * 1b2) test_and_set the cpu bit in cpu_vm_mask. - * Atomically set the bit [other cpus will start sending flush ipis], - * and test the bit. - * 1b3) if the bit was 0: leave_mm was called, flush the tlb. - * 2) switch %%esp, ie current - * - * The interrupt must handle 2 special cases: - * - cr3 is changed before %%esp, ie. it cannot use current->{active_,}mm. - * - the cpu performs speculative tlb reads, i.e. even if the cpu only - * runs in kernel space, the cpu could load tlb entries for user space - * pages. - * - * The good news is that cpu mmu_state is local to each cpu, no - * write/read ordering problems. - */ - -/* - * TLB flush IPI: - * - * 1) Flush the tlb entries if the cpu uses the mm that's being flushed. - * 2) Leave the mm if we are in the lazy tlb mode. - */ - -asmlinkage void smp_invalidate_interrupt (void) -{ - unsigned long cpu; - - cpu = get_cpu(); - - if (!cpu_isset(cpu, flush_cpumask)) - goto out; - /* - * This was a BUG() but until someone can quote me the - * line from the intel manual that guarantees an IPI to - * multiple CPUs is retried _only_ on the erroring CPUs - * its staying as a return - * - * BUG(); - */ - - if (flush_mm == read_pda(active_mm)) { - if (read_pda(mmu_state) == TLBSTATE_OK) { - if (flush_va == FLUSH_ALL) - local_flush_tlb(); - else - __flush_tlb_one(flush_va); - } else - leave_mm(cpu); - } -out: - ack_APIC_irq(); - cpu_clear(cpu, flush_cpumask); - put_cpu_no_resched(); -} - -static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm, - unsigned long va) -{ - cpumask_t tmp; - /* - * A couple of (to be removed) sanity checks: - * - * - we do not send IPIs to not-yet booted CPUs. - * - current CPU must not be in mask - * - mask must exist :) - */ - BUG_ON(cpus_empty(cpumask)); - cpus_and(tmp, cpumask, cpu_online_map); - BUG_ON(!cpus_equal(tmp, cpumask)); - BUG_ON(cpu_isset(smp_processor_id(), cpumask)); - if (!mm) - BUG(); - - /* - * I'm not happy about this global shared spinlock in the - * MM hot path, but we'll see how contended it is. - * Temporarily this turns IRQs off, so that lockups are - * detected by the NMI watchdog. - */ - spin_lock(&tlbstate_lock); - - flush_mm = mm; - flush_va = va; - cpus_or(flush_cpumask, cpumask, flush_cpumask); - - /* - * We have to send the IPI only to - * CPUs affected. - */ - send_IPI_mask(cpumask, INVALIDATE_TLB_VECTOR); - - while (!cpus_empty(flush_cpumask)) - mb(); /* nothing. lockup detection does not belong here */; - - flush_mm = NULL; - flush_va = 0; - spin_unlock(&tlbstate_lock); -} - -void flush_tlb_current_task(void) -{ - struct mm_struct *mm = current->mm; - cpumask_t cpu_mask; - - preempt_disable(); - cpu_mask = mm->cpu_vm_mask; - cpu_clear(smp_processor_id(), cpu_mask); - - local_flush_tlb(); - if (!cpus_empty(cpu_mask)) - flush_tlb_others(cpu_mask, mm, FLUSH_ALL); - preempt_enable(); -} - -void flush_tlb_mm (struct mm_struct * mm) -{ - cpumask_t cpu_mask; - - preempt_disable(); - cpu_mask = mm->cpu_vm_mask; - cpu_clear(smp_processor_id(), cpu_mask); - - if (current->active_mm == mm) { - if (current->mm) - local_flush_tlb(); - else - leave_mm(smp_processor_id()); - } - if (!cpus_empty(cpu_mask)) - flush_tlb_others(cpu_mask, mm, FLUSH_ALL); - - preempt_enable(); -} - -void flush_tlb_page(struct vm_area_struct * vma, unsigned long va) -{ - struct mm_struct *mm = vma->vm_mm; - cpumask_t cpu_mask; - - preempt_disable(); - cpu_mask = mm->cpu_vm_mask; - cpu_clear(smp_processor_id(), cpu_mask); - - if (current->active_mm == mm) { - if(current->mm) - __flush_tlb_one(va); - else - leave_mm(smp_processor_id()); - } - - if (!cpus_empty(cpu_mask)) - flush_tlb_others(cpu_mask, mm, va); - - preempt_enable(); -} - -static void do_flush_tlb_all(void* info) -{ - unsigned long cpu = smp_processor_id(); - - __flush_tlb_all(); - if (read_pda(mmu_state) == TLBSTATE_LAZY) - leave_mm(cpu); -} - -void flush_tlb_all(void) -{ - on_each_cpu(do_flush_tlb_all, NULL, 1, 1); -} - -void smp_kdb_stop(void) -{ - send_IPI_allbutself(KDB_VECTOR); -} - -/* - * this function sends a 'reschedule' IPI to another CPU. - * it goes straight through and wastes no time serializing - * anything. Worst case is that we lose a reschedule ... - */ - -void smp_send_reschedule(int cpu) -{ - send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR); -} - -/* - * Structure and data for smp_call_function(). This is designed to minimise - * static memory requirements. It also looks cleaner. - */ -static DEFINE_SPINLOCK(call_lock); - -struct call_data_struct { - void (*func) (void *info); - void *info; - atomic_t started; - atomic_t finished; - int wait; -}; - -static struct call_data_struct * call_data; - -void lock_ipi_call_lock(void) -{ - spin_lock_irq(&call_lock); -} - -void unlock_ipi_call_lock(void) -{ - spin_unlock_irq(&call_lock); -} - -/* - * this function sends a 'generic call function' IPI to all other CPUs - * in the system. - */ -static void __smp_call_function (void (*func) (void *info), void *info, - int nonatomic, int wait) -{ - struct call_data_struct data; - int cpus = num_online_cpus()-1; - - if (!cpus) - return; - - data.func = func; - data.info = info; - atomic_set(&data.started, 0); - data.wait = wait; - if (wait) - atomic_set(&data.finished, 0); - - call_data = &data; - wmb(); - /* Send a message to all other CPUs and wait for them to respond */ - send_IPI_allbutself(CALL_FUNCTION_VECTOR); - - /* Wait for response */ - while (atomic_read(&data.started) != cpus) - cpu_relax(); - - if (!wait) - return; - - while (atomic_read(&data.finished) != cpus) - cpu_relax(); -} - -/* - * smp_call_function - 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. - * @nonatomic: currently unused. - * @wait: If true, wait (atomically) 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. - * Actually there are a few legal cases, like panic. - */ -int smp_call_function (void (*func) (void *info), void *info, int nonatomic, - int wait) -{ - spin_lock(&call_lock); - __smp_call_function(func,info,nonatomic,wait); - spin_unlock(&call_lock); - return 0; -} - -void smp_stop_cpu(void) -{ - /* - * Remove this CPU: - */ - cpu_clear(smp_processor_id(), cpu_online_map); - local_irq_disable(); - disable_local_APIC(); - local_irq_enable(); -} - -static void smp_really_stop_cpu(void *dummy) -{ - smp_stop_cpu(); - for (;;) - asm("hlt"); -} - -void smp_send_stop(void) -{ - int nolock = 0; - if (reboot_force) - return; - /* Don't deadlock on the call lock in panic */ - if (!spin_trylock(&call_lock)) { - /* ignore locking because we have paniced anyways */ - nolock = 1; - } - __smp_call_function(smp_really_stop_cpu, NULL, 0, 0); - if (!nolock) - spin_unlock(&call_lock); - - local_irq_disable(); - disable_local_APIC(); - local_irq_enable(); -} - -/* - * Reschedule call back. Nothing to do, - * all the work is done automatically when - * we return from the interrupt. - */ -asmlinkage void smp_reschedule_interrupt(void) -{ - ack_APIC_irq(); -} - -asmlinkage void smp_call_function_interrupt(void) -{ - void (*func) (void *info) = call_data->func; - void *info = call_data->info; - int wait = call_data->wait; - - ack_APIC_irq(); - /* - * Notify initiating CPU that I've grabbed the data and am - * about to execute the function - */ - mb(); - atomic_inc(&call_data->started); - /* - * At this point the info structure may be out of scope unless wait==1 - */ - irq_enter(); - (*func)(info); - irq_exit(); - if (wait) { - mb(); - atomic_inc(&call_data->finished); - } -} - -int safe_smp_processor_id(void) -{ - int apicid, i; - - if (disable_apic) - return 0; - - apicid = hard_smp_processor_id(); - if (x86_cpu_to_apicid[apicid] == apicid) - return apicid; - - for (i = 0; i < NR_CPUS; ++i) { - if (x86_cpu_to_apicid[i] == apicid) - return i; - } - - /* No entries in x86_cpu_to_apicid? Either no MPS|ACPI, - * or called too early. Either way, we must be CPU 0. */ - if (x86_cpu_to_apicid[0] == BAD_APICID) - return 0; - - return 0; /* Should not happen */ -} |
