diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/smp_64.c | 74 |
1 files changed, 35 insertions, 39 deletions
diff --git a/arch/x86/kernel/smp_64.c b/arch/x86/kernel/smp_64.c index 03fa6ed559c..62b0f2a1b1e 100644 --- a/arch/x86/kernel/smp_64.c +++ b/arch/x86/kernel/smp_64.c @@ -29,7 +29,7 @@ #include <asm/idle.h> /* - * Smarter SMP flushing macros. + * Smarter SMP flushing macros. * c/o Linus Torvalds. * * These mean you can really definitely utterly forget about @@ -37,15 +37,15 @@ * * Optimizations Manfred Spraul <manfred@colorfullife.com> * - * More scalable flush, from Andi Kleen + * More scalable flush, from Andi Kleen * - * To avoid global state use 8 different call vectors. - * Each CPU uses a specific vector to trigger flushes on other - * CPUs. Depending on the received vector the target CPUs look into + * To avoid global state use 8 different call vectors. + * Each CPU uses a specific vector to trigger flushes on other + * CPUs. Depending on the received vector the target CPUs look into * the right per cpu variable for the flush data. * - * With more than 8 CPUs they are hashed to the 8 available - * vectors. The limited global vector space forces us to this right now. + * With more than 8 CPUs they are hashed to the 8 available + * vectors. The limited global vector space forces us to this right now. * In future when interrupts are split into per CPU domains this could be * fixed, at the cost of triggering multiple IPIs in some cases. */ @@ -67,7 +67,7 @@ union smp_flush_state { static DEFINE_PER_CPU(union smp_flush_state, flush_state); /* - * We cannot call mmdrop() because we are in interrupt context, + * We cannot call mmdrop() because we are in interrupt context, * instead update mm->cpu_vm_mask. */ static inline void leave_mm(int cpu) @@ -85,25 +85,25 @@ static inline void leave_mm(int cpu) * 1) switch_mm() either 1a) or 1b) * 1a) thread switch to a different mm * 1a1) cpu_clear(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. + * 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 + * 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. + * Now cpu0 accepts tlb flushes for the new mm. * 1a4) cpu_set(cpu, new_mm->cpu_vm_mask); - * Now the other cpus will send tlb flush ipis. + * 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. + * 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 * @@ -142,7 +142,7 @@ asmlinkage void smp_invalidate_interrupt(struct pt_regs *regs) if (!cpu_isset(cpu, f->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 @@ -150,7 +150,7 @@ asmlinkage void smp_invalidate_interrupt(struct pt_regs *regs) * * BUG(); */ - + if (f->flush_mm == read_pda(active_mm)) { if (read_pda(mmu_state) == TLBSTATE_OK) { if (f->flush_va == FLUSH_ALL) @@ -176,9 +176,11 @@ static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm, sender = smp_processor_id() % NUM_INVALIDATE_TLB_VECTORS; f = &per_cpu(flush_state, sender); - /* Could avoid this lock when - num_online_cpus() <= NUM_INVALIDATE_TLB_VECTORS, but it is - probably not worth checking this for a cache-hot lock. */ + /* + * Could avoid this lock when + * num_online_cpus() <= NUM_INVALIDATE_TLB_VECTORS, but it is + * probably not worth checking this for a cache-hot lock. + */ spin_lock(&f->tlbstate_lock); f->flush_mm = mm; @@ -202,14 +204,14 @@ static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm, int __cpuinit init_smp_flush(void) { int i; + for_each_cpu_mask(i, cpu_possible_map) { spin_lock_init(&per_cpu(flush_state, i).tlbstate_lock); } return 0; } - core_initcall(init_smp_flush); - + void flush_tlb_current_task(void) { struct mm_struct *mm = current->mm; @@ -224,7 +226,6 @@ void flush_tlb_current_task(void) flush_tlb_others(cpu_mask, mm, FLUSH_ALL); preempt_enable(); } -EXPORT_SYMBOL(flush_tlb_current_task); void flush_tlb_mm (struct mm_struct * mm) { @@ -245,7 +246,6 @@ void flush_tlb_mm (struct mm_struct * mm) preempt_enable(); } -EXPORT_SYMBOL(flush_tlb_mm); void flush_tlb_page(struct vm_area_struct * vma, unsigned long va) { @@ -259,8 +259,8 @@ void flush_tlb_page(struct vm_area_struct * vma, unsigned long va) if (current->active_mm == mm) { if(current->mm) __flush_tlb_one(va); - else - leave_mm(smp_processor_id()); + else + leave_mm(smp_processor_id()); } if (!cpus_empty(cpu_mask)) @@ -268,7 +268,6 @@ void flush_tlb_page(struct vm_area_struct * vma, unsigned long va) preempt_enable(); } -EXPORT_SYMBOL(flush_tlb_page); static void do_flush_tlb_all(void* info) { @@ -325,11 +324,9 @@ void unlock_ipi_call_lock(void) * this function sends a 'generic call function' IPI to all other CPU * of the system defined in the mask. */ - -static int -__smp_call_function_mask(cpumask_t mask, - void (*func)(void *), void *info, - int wait) +static int __smp_call_function_mask(cpumask_t mask, + void (*func)(void *), void *info, + int wait) { struct call_data_struct data; cpumask_t allbutself; @@ -417,11 +414,10 @@ EXPORT_SYMBOL(smp_call_function_mask); */ int smp_call_function_single (int cpu, void (*func) (void *info), void *info, - int nonatomic, int wait) + int nonatomic, int wait) { /* prevent preemption and reschedule on another processor */ - int ret; - int me = get_cpu(); + int ret, me = get_cpu(); /* Can deadlock when called with interrupts disabled */ WARN_ON(irqs_disabled()); @@ -471,9 +467,9 @@ static void stop_this_cpu(void *dummy) */ cpu_clear(smp_processor_id(), cpu_online_map); disable_local_APIC(); - for (;;) + for (;;) halt(); -} +} void smp_send_stop(void) { |