obj-$(CONFIG_X86_CPUID) += cpuid.o
obj-$(CONFIG_MICROCODE) += microcode.o
obj-$(CONFIG_APM) += apm.o
-obj-$(CONFIG_X86_SMP) += smp.o smpboot.o tsc_sync.o
+obj-$(CONFIG_X86_SMP) += smp_32.o smpboot.o tsc_sync.o
obj-$(CONFIG_SMP) += smpcommon.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o
obj-$(CONFIG_X86_MPPARSE) += mpparse.o
+++ /dev/null
-/*
- * Intel SMP support routines.
- *
- * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
- * (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com>
- *
- * This code is released under the GNU General Public License version 2 or
- * later.
- */
-
-#include <linux/init.h>
-
-#include <linux/mm.h>
-#include <linux/delay.h>
-#include <linux/spinlock.h>
-#include <linux/kernel_stat.h>
-#include <linux/mc146818rtc.h>
-#include <linux/cache.h>
-#include <linux/interrupt.h>
-#include <linux/cpu.h>
-#include <linux/module.h>
-
-#include <asm/mtrr.h>
-#include <asm/tlbflush.h>
-#include <asm/mmu_context.h>
-#include <mach_apic.h>
-
-/*
- * Some notes on x86 processor bugs affecting SMP operation:
- *
- * Pentium, Pentium Pro, II, III (and all CPUs) have bugs.
- * The Linux implications for SMP are handled as follows:
- *
- * Pentium III / [Xeon]
- * None of the E1AP-E3AP errata are visible to the user.
- *
- * E1AP. see PII A1AP
- * E2AP. see PII A2AP
- * E3AP. see PII A3AP
- *
- * Pentium II / [Xeon]
- * None of the A1AP-A3AP errata are visible to the user.
- *
- * A1AP. see PPro 1AP
- * A2AP. see PPro 2AP
- * A3AP. see PPro 7AP
- *
- * Pentium Pro
- * None of 1AP-9AP errata are visible to the normal user,
- * except occasional delivery of 'spurious interrupt' as trap #15.
- * This is very rare and a non-problem.
- *
- * 1AP. Linux maps APIC as non-cacheable
- * 2AP. worked around in hardware
- * 3AP. fixed in C0 and above steppings microcode update.
- * Linux does not use excessive STARTUP_IPIs.
- * 4AP. worked around in hardware
- * 5AP. symmetric IO mode (normal Linux operation) not affected.
- * 'noapic' mode has vector 0xf filled out properly.
- * 6AP. 'noapic' mode might be affected - fixed in later steppings
- * 7AP. We do not assume writes to the LVT deassering IRQs
- * 8AP. We do not enable low power mode (deep sleep) during MP bootup
- * 9AP. We do not use mixed mode
- *
- * Pentium
- * There is a marginal case where REP MOVS on 100MHz SMP
- * machines with B stepping processors can fail. XXX should provide
- * an L1cache=Writethrough or L1cache=off option.
- *
- * B stepping CPUs may hang. There are hardware work arounds
- * for this. We warn about it in case your board doesn't have the work
- * arounds. Basically thats so I can tell anyone with a B stepping
- * CPU and SMP problems "tough".
- *
- * Specific items [From Pentium Processor Specification Update]
- *
- * 1AP. Linux doesn't use remote read
- * 2AP. Linux doesn't trust APIC errors
- * 3AP. We work around this
- * 4AP. Linux never generated 3 interrupts of the same priority
- * to cause a lost local interrupt.
- * 5AP. Remote read is never used
- * 6AP. not affected - worked around in hardware
- * 7AP. not affected - worked around in hardware
- * 8AP. worked around in hardware - we get explicit CS errors if not
- * 9AP. only 'noapic' mode affected. Might generate spurious
- * interrupts, we log only the first one and count the
- * rest silently.
- * 10AP. not affected - worked around in hardware
- * 11AP. Linux reads the APIC between writes to avoid this, as per
- * the documentation. Make sure you preserve this as it affects
- * the C stepping chips too.
- * 12AP. not affected - worked around in hardware
- * 13AP. not affected - worked around in hardware
- * 14AP. we always deassert INIT during bootup
- * 15AP. not affected - worked around in hardware
- * 16AP. not affected - worked around in hardware
- * 17AP. not affected - worked around in hardware
- * 18AP. not affected - worked around in hardware
- * 19AP. not affected - worked around in BIOS
- *
- * If this sounds worrying believe me these bugs are either ___RARE___,
- * or are signal timing bugs worked around in hardware and there's
- * about nothing of note with C stepping upwards.
- */
-
-DEFINE_PER_CPU(struct tlb_state, cpu_tlbstate) ____cacheline_aligned = { &init_mm, 0, };
-
-/*
- * the following functions deal with sending IPIs between CPUs.
- *
- * We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
- */
-
-static inline int __prepare_ICR (unsigned int shortcut, int vector)
-{
- unsigned int icr = shortcut | APIC_DEST_LOGICAL;
-
- switch (vector) {
- default:
- icr |= APIC_DM_FIXED | vector;
- break;
- case NMI_VECTOR:
- icr |= APIC_DM_NMI;
- break;
- }
- return icr;
-}
-
-static inline int __prepare_ICR2 (unsigned int mask)
-{
- return SET_APIC_DEST_FIELD(mask);
-}
-
-void __send_IPI_shortcut(unsigned int shortcut, int vector)
-{
- /*
- * Subtle. In the case of the 'never do double writes' workaround
- * we have to lock out interrupts to be safe. As we don't care
- * of the value read we use an atomic rmw access to avoid costly
- * cli/sti. Otherwise we use an even cheaper single atomic write
- * to the APIC.
- */
- unsigned int cfg;
-
- /*
- * Wait for idle.
- */
- apic_wait_icr_idle();
-
- /*
- * No need to touch the target chip field
- */
- cfg = __prepare_ICR(shortcut, vector);
-
- /*
- * Send the IPI. The write to APIC_ICR fires this off.
- */
- apic_write_around(APIC_ICR, cfg);
-}
-
-void fastcall send_IPI_self(int vector)
-{
- __send_IPI_shortcut(APIC_DEST_SELF, vector);
-}
-
-/*
- * This is used to send an IPI with no shorthand notation (the destination is
- * specified in bits 56 to 63 of the ICR).
- */
-static inline void __send_IPI_dest_field(unsigned long mask, int vector)
-{
- unsigned long cfg;
-
- /*
- * Wait for idle.
- */
- if (unlikely(vector == NMI_VECTOR))
- safe_apic_wait_icr_idle();
- else
- apic_wait_icr_idle();
-
- /*
- * prepare target chip field
- */
- cfg = __prepare_ICR2(mask);
- apic_write_around(APIC_ICR2, cfg);
-
- /*
- * program the ICR
- */
- cfg = __prepare_ICR(0, vector);
-
- /*
- * Send the IPI. The write to APIC_ICR fires this off.
- */
- apic_write_around(APIC_ICR, cfg);
-}
-
-/*
- * This is only used on smaller machines.
- */
-void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
-{
- unsigned long mask = cpus_addr(cpumask)[0];
- unsigned long flags;
-
- local_irq_save(flags);
- WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
- __send_IPI_dest_field(mask, vector);
- local_irq_restore(flags);
-}
-
-void send_IPI_mask_sequence(cpumask_t mask, int vector)
-{
- unsigned long flags;
- unsigned int query_cpu;
-
- /*
- * Hack. The clustered APIC addressing mode doesn't allow us to send
- * to an arbitrary mask, so I do a unicasts to each CPU instead. This
- * should be modified to do 1 message per cluster ID - mbligh
- */
-
- local_irq_save(flags);
- for (query_cpu = 0; query_cpu < NR_CPUS; ++query_cpu) {
- if (cpu_isset(query_cpu, mask)) {
- __send_IPI_dest_field(cpu_to_logical_apicid(query_cpu),
- vector);
- }
- }
- local_irq_restore(flags);
-}
-
-#include <mach_ipi.h> /* must come after the send_IPI functions above for inlining */
-
-/*
- * 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);
-
-/*
- * We cannot call mmdrop() because we are in interrupt context,
- * instead update mm->cpu_vm_mask.
- *
- * We need to reload %cr3 since the page tables may be going
- * away from under us..
- */
-void leave_mm(unsigned long cpu)
-{
- if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK)
- BUG();
- cpu_clear(cpu, per_cpu(cpu_tlbstate, cpu).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) 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 superflous
- * tlb flush.
- * 1a2) set cpu_tlbstate to TLBSTATE_OK
- * Now the smp_invalidate_interrupt won't call leave_mm if cpu0
- * was in lazy tlb mode.
- * 1a3) update cpu_tlbstate[].active_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.
- * 1a4) change cr3.
- * 1b) thread switch without mm change
- * cpu_tlbstate[].active_mm is correct, cpu0 already handles
- * flush ipis.
- * 1b1) set cpu_tlbstate 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_tlbstate 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.
- */
-
-fastcall void smp_invalidate_interrupt(struct pt_regs *regs)
-{
- 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 == per_cpu(cpu_tlbstate, cpu).active_mm) {
- if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK) {
- if (flush_va == TLB_FLUSH_ALL)
- local_flush_tlb();
- else
- __flush_tlb_one(flush_va);
- } else
- leave_mm(cpu);
- }
- ack_APIC_irq();
- smp_mb__before_clear_bit();
- cpu_clear(cpu, flush_cpumask);
- smp_mb__after_clear_bit();
-out:
- put_cpu_no_resched();
-}
-
-void native_flush_tlb_others(const cpumask_t *cpumaskp, struct mm_struct *mm,
- unsigned long va)
-{
- cpumask_t cpumask = *cpumaskp;
-
- /*
- * A couple of (to be removed) sanity checks:
- *
- * - current CPU must not be in mask
- * - mask must exist :)
- */
- BUG_ON(cpus_empty(cpumask));
- BUG_ON(cpu_isset(smp_processor_id(), cpumask));
- BUG_ON(!mm);
-
-#ifdef CONFIG_HOTPLUG_CPU
- /* If a CPU which we ran on has gone down, OK. */
- cpus_and(cpumask, cpumask, cpu_online_map);
- if (unlikely(cpus_empty(cpumask)))
- return;
-#endif
-
- /*
- * i'm not happy about this global shared spinlock in the
- * MM hot path, but we'll see how contended it is.
- * AK: x86-64 has a faster method that could be ported.
- */
- 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))
- /* nothing. lockup detection does not belong here */
- cpu_relax();
-
- 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, TLB_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, TLB_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();
-}
-EXPORT_SYMBOL(flush_tlb_page);
-
-static void do_flush_tlb_all(void* info)
-{
- unsigned long cpu = smp_processor_id();
-
- __flush_tlb_all();
- if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_LAZY)
- leave_mm(cpu);
-}
-
-void flush_tlb_all(void)
-{
- on_each_cpu(do_flush_tlb_all, NULL, 1, 1);
-}
-
-/*
- * 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 ...
- */
-static void native_smp_send_reschedule(int cpu)
-{
- WARN_ON(cpu_is_offline(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;
-};
-
-void lock_ipi_call_lock(void)
-{
- spin_lock_irq(&call_lock);
-}
-
-void unlock_ipi_call_lock(void)
-{
- spin_unlock_irq(&call_lock);
-}
-
-static struct call_data_struct *call_data;
-
-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;
- mb();
-
- /* 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)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
-}
-
-
-/**
- * smp_call_function_mask(): Run a function on a set of other CPUs.
- * @mask: The set of cpus to run on. Must not include the current cpu.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @wait: If true, wait (atomically) until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-static int
-native_smp_call_function_mask(cpumask_t mask,
- void (*func)(void *), void *info,
- int wait)
-{
- struct call_data_struct data;
- cpumask_t allbutself;
- int cpus;
-
- /* Can deadlock when called with interrupts disabled */
- WARN_ON(irqs_disabled());
-
- /* Holding any lock stops cpus from going down. */
- spin_lock(&call_lock);
-
- allbutself = cpu_online_map;
- cpu_clear(smp_processor_id(), allbutself);
-
- cpus_and(mask, mask, allbutself);
- cpus = cpus_weight(mask);
-
- if (!cpus) {
- spin_unlock(&call_lock);
- return 0;
- }
-
- data.func = func;
- data.info = info;
- atomic_set(&data.started, 0);
- data.wait = wait;
- if (wait)
- atomic_set(&data.finished, 0);
-
- call_data = &data;
- mb();
-
- /* Send a message to other CPUs */
- if (cpus_equal(mask, allbutself))
- send_IPI_allbutself(CALL_FUNCTION_VECTOR);
- else
- send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
- spin_unlock(&call_lock);
-
- return 0;
-}
-
-static void stop_this_cpu (void * dummy)
-{
- local_irq_disable();
- /*
- * Remove this CPU:
- */
- cpu_clear(smp_processor_id(), cpu_online_map);
- disable_local_APIC();
- if (cpu_data[smp_processor_id()].hlt_works_ok)
- for(;;) halt();
- for (;;);
-}
-
-/*
- * this function calls the 'stop' function on all other CPUs in the system.
- */
-
-static void native_smp_send_stop(void)
-{
- /* Don't deadlock on the call lock in panic */
- int nolock = !spin_trylock(&call_lock);
- unsigned long flags;
-
- local_irq_save(flags);
- __smp_call_function(stop_this_cpu, NULL, 0, 0);
- if (!nolock)
- spin_unlock(&call_lock);
- disable_local_APIC();
- local_irq_restore(flags);
-}
-
-/*
- * Reschedule call back. Nothing to do,
- * all the work is done automatically when
- * we return from the interrupt.
- */
-fastcall void smp_reschedule_interrupt(struct pt_regs *regs)
-{
- ack_APIC_irq();
-}
-
-fastcall void smp_call_function_interrupt(struct pt_regs *regs)
-{
- 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);
- }
-}
-
-static int convert_apicid_to_cpu(int apic_id)
-{
- int i;
-
- for (i = 0; i < NR_CPUS; i++) {
- if (x86_cpu_to_apicid[i] == apic_id)
- return i;
- }
- return -1;
-}
-
-int safe_smp_processor_id(void)
-{
- int apicid, cpuid;
-
- if (!boot_cpu_has(X86_FEATURE_APIC))
- return 0;
-
- apicid = hard_smp_processor_id();
- if (apicid == BAD_APICID)
- return 0;
-
- cpuid = convert_apicid_to_cpu(apicid);
-
- return cpuid >= 0 ? cpuid : 0;
-}
-
-struct smp_ops smp_ops = {
- .smp_prepare_boot_cpu = native_smp_prepare_boot_cpu,
- .smp_prepare_cpus = native_smp_prepare_cpus,
- .cpu_up = native_cpu_up,
- .smp_cpus_done = native_smp_cpus_done,
-
- .smp_send_stop = native_smp_send_stop,
- .smp_send_reschedule = native_smp_send_reschedule,
- .smp_call_function_mask = native_smp_call_function_mask,
-};
--- /dev/null
+/*
+ * Intel SMP support routines.
+ *
+ * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
+ * (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com>
+ *
+ * This code is released under the GNU General Public License version 2 or
+ * later.
+ */
+
+#include <linux/init.h>
+
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/kernel_stat.h>
+#include <linux/mc146818rtc.h>
+#include <linux/cache.h>
+#include <linux/interrupt.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+
+#include <asm/mtrr.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+#include <mach_apic.h>
+
+/*
+ * Some notes on x86 processor bugs affecting SMP operation:
+ *
+ * Pentium, Pentium Pro, II, III (and all CPUs) have bugs.
+ * The Linux implications for SMP are handled as follows:
+ *
+ * Pentium III / [Xeon]
+ * None of the E1AP-E3AP errata are visible to the user.
+ *
+ * E1AP. see PII A1AP
+ * E2AP. see PII A2AP
+ * E3AP. see PII A3AP
+ *
+ * Pentium II / [Xeon]
+ * None of the A1AP-A3AP errata are visible to the user.
+ *
+ * A1AP. see PPro 1AP
+ * A2AP. see PPro 2AP
+ * A3AP. see PPro 7AP
+ *
+ * Pentium Pro
+ * None of 1AP-9AP errata are visible to the normal user,
+ * except occasional delivery of 'spurious interrupt' as trap #15.
+ * This is very rare and a non-problem.
+ *
+ * 1AP. Linux maps APIC as non-cacheable
+ * 2AP. worked around in hardware
+ * 3AP. fixed in C0 and above steppings microcode update.
+ * Linux does not use excessive STARTUP_IPIs.
+ * 4AP. worked around in hardware
+ * 5AP. symmetric IO mode (normal Linux operation) not affected.
+ * 'noapic' mode has vector 0xf filled out properly.
+ * 6AP. 'noapic' mode might be affected - fixed in later steppings
+ * 7AP. We do not assume writes to the LVT deassering IRQs
+ * 8AP. We do not enable low power mode (deep sleep) during MP bootup
+ * 9AP. We do not use mixed mode
+ *
+ * Pentium
+ * There is a marginal case where REP MOVS on 100MHz SMP
+ * machines with B stepping processors can fail. XXX should provide
+ * an L1cache=Writethrough or L1cache=off option.
+ *
+ * B stepping CPUs may hang. There are hardware work arounds
+ * for this. We warn about it in case your board doesn't have the work
+ * arounds. Basically thats so I can tell anyone with a B stepping
+ * CPU and SMP problems "tough".
+ *
+ * Specific items [From Pentium Processor Specification Update]
+ *
+ * 1AP. Linux doesn't use remote read
+ * 2AP. Linux doesn't trust APIC errors
+ * 3AP. We work around this
+ * 4AP. Linux never generated 3 interrupts of the same priority
+ * to cause a lost local interrupt.
+ * 5AP. Remote read is never used
+ * 6AP. not affected - worked around in hardware
+ * 7AP. not affected - worked around in hardware
+ * 8AP. worked around in hardware - we get explicit CS errors if not
+ * 9AP. only 'noapic' mode affected. Might generate spurious
+ * interrupts, we log only the first one and count the
+ * rest silently.
+ * 10AP. not affected - worked around in hardware
+ * 11AP. Linux reads the APIC between writes to avoid this, as per
+ * the documentation. Make sure you preserve this as it affects
+ * the C stepping chips too.
+ * 12AP. not affected - worked around in hardware
+ * 13AP. not affected - worked around in hardware
+ * 14AP. we always deassert INIT during bootup
+ * 15AP. not affected - worked around in hardware
+ * 16AP. not affected - worked around in hardware
+ * 17AP. not affected - worked around in hardware
+ * 18AP. not affected - worked around in hardware
+ * 19AP. not affected - worked around in BIOS
+ *
+ * If this sounds worrying believe me these bugs are either ___RARE___,
+ * or are signal timing bugs worked around in hardware and there's
+ * about nothing of note with C stepping upwards.
+ */
+
+DEFINE_PER_CPU(struct tlb_state, cpu_tlbstate) ____cacheline_aligned = { &init_mm, 0, };
+
+/*
+ * the following functions deal with sending IPIs between CPUs.
+ *
+ * We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
+ */
+
+static inline int __prepare_ICR (unsigned int shortcut, int vector)
+{
+ unsigned int icr = shortcut | APIC_DEST_LOGICAL;
+
+ switch (vector) {
+ default:
+ icr |= APIC_DM_FIXED | vector;
+ break;
+ case NMI_VECTOR:
+ icr |= APIC_DM_NMI;
+ break;
+ }
+ return icr;
+}
+
+static inline int __prepare_ICR2 (unsigned int mask)
+{
+ return SET_APIC_DEST_FIELD(mask);
+}
+
+void __send_IPI_shortcut(unsigned int shortcut, int vector)
+{
+ /*
+ * Subtle. In the case of the 'never do double writes' workaround
+ * we have to lock out interrupts to be safe. As we don't care
+ * of the value read we use an atomic rmw access to avoid costly
+ * cli/sti. Otherwise we use an even cheaper single atomic write
+ * to the APIC.
+ */
+ unsigned int cfg;
+
+ /*
+ * Wait for idle.
+ */
+ apic_wait_icr_idle();
+
+ /*
+ * No need to touch the target chip field
+ */
+ cfg = __prepare_ICR(shortcut, vector);
+
+ /*
+ * Send the IPI. The write to APIC_ICR fires this off.
+ */
+ apic_write_around(APIC_ICR, cfg);
+}
+
+void fastcall send_IPI_self(int vector)
+{
+ __send_IPI_shortcut(APIC_DEST_SELF, vector);
+}
+
+/*
+ * This is used to send an IPI with no shorthand notation (the destination is
+ * specified in bits 56 to 63 of the ICR).
+ */
+static inline void __send_IPI_dest_field(unsigned long mask, int vector)
+{
+ unsigned long cfg;
+
+ /*
+ * Wait for idle.
+ */
+ if (unlikely(vector == NMI_VECTOR))
+ safe_apic_wait_icr_idle();
+ else
+ apic_wait_icr_idle();
+
+ /*
+ * prepare target chip field
+ */
+ cfg = __prepare_ICR2(mask);
+ apic_write_around(APIC_ICR2, cfg);
+
+ /*
+ * program the ICR
+ */
+ cfg = __prepare_ICR(0, vector);
+
+ /*
+ * Send the IPI. The write to APIC_ICR fires this off.
+ */
+ apic_write_around(APIC_ICR, cfg);
+}
+
+/*
+ * This is only used on smaller machines.
+ */
+void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
+{
+ unsigned long mask = cpus_addr(cpumask)[0];
+ unsigned long flags;
+
+ local_irq_save(flags);
+ WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
+ __send_IPI_dest_field(mask, vector);
+ local_irq_restore(flags);
+}
+
+void send_IPI_mask_sequence(cpumask_t mask, int vector)
+{
+ unsigned long flags;
+ unsigned int query_cpu;
+
+ /*
+ * Hack. The clustered APIC addressing mode doesn't allow us to send
+ * to an arbitrary mask, so I do a unicasts to each CPU instead. This
+ * should be modified to do 1 message per cluster ID - mbligh
+ */
+
+ local_irq_save(flags);
+ for (query_cpu = 0; query_cpu < NR_CPUS; ++query_cpu) {
+ if (cpu_isset(query_cpu, mask)) {
+ __send_IPI_dest_field(cpu_to_logical_apicid(query_cpu),
+ vector);
+ }
+ }
+ local_irq_restore(flags);
+}
+
+#include <mach_ipi.h> /* must come after the send_IPI functions above for inlining */
+
+/*
+ * 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);
+
+/*
+ * We cannot call mmdrop() because we are in interrupt context,
+ * instead update mm->cpu_vm_mask.
+ *
+ * We need to reload %cr3 since the page tables may be going
+ * away from under us..
+ */
+void leave_mm(unsigned long cpu)
+{
+ if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK)
+ BUG();
+ cpu_clear(cpu, per_cpu(cpu_tlbstate, cpu).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) 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 superflous
+ * tlb flush.
+ * 1a2) set cpu_tlbstate to TLBSTATE_OK
+ * Now the smp_invalidate_interrupt won't call leave_mm if cpu0
+ * was in lazy tlb mode.
+ * 1a3) update cpu_tlbstate[].active_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.
+ * 1a4) change cr3.
+ * 1b) thread switch without mm change
+ * cpu_tlbstate[].active_mm is correct, cpu0 already handles
+ * flush ipis.
+ * 1b1) set cpu_tlbstate 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_tlbstate 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.
+ */
+
+fastcall void smp_invalidate_interrupt(struct pt_regs *regs)
+{
+ 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 == per_cpu(cpu_tlbstate, cpu).active_mm) {
+ if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK) {
+ if (flush_va == TLB_FLUSH_ALL)
+ local_flush_tlb();
+ else
+ __flush_tlb_one(flush_va);
+ } else
+ leave_mm(cpu);
+ }
+ ack_APIC_irq();
+ smp_mb__before_clear_bit();
+ cpu_clear(cpu, flush_cpumask);
+ smp_mb__after_clear_bit();
+out:
+ put_cpu_no_resched();
+}
+
+void native_flush_tlb_others(const cpumask_t *cpumaskp, struct mm_struct *mm,
+ unsigned long va)
+{
+ cpumask_t cpumask = *cpumaskp;
+
+ /*
+ * A couple of (to be removed) sanity checks:
+ *
+ * - current CPU must not be in mask
+ * - mask must exist :)
+ */
+ BUG_ON(cpus_empty(cpumask));
+ BUG_ON(cpu_isset(smp_processor_id(), cpumask));
+ BUG_ON(!mm);
+
+#ifdef CONFIG_HOTPLUG_CPU
+ /* If a CPU which we ran on has gone down, OK. */
+ cpus_and(cpumask, cpumask, cpu_online_map);
+ if (unlikely(cpus_empty(cpumask)))
+ return;
+#endif
+
+ /*
+ * i'm not happy about this global shared spinlock in the
+ * MM hot path, but we'll see how contended it is.
+ * AK: x86-64 has a faster method that could be ported.
+ */
+ 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))
+ /* nothing. lockup detection does not belong here */
+ cpu_relax();
+
+ 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, TLB_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, TLB_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();
+}
+EXPORT_SYMBOL(flush_tlb_page);
+
+static void do_flush_tlb_all(void* info)
+{
+ unsigned long cpu = smp_processor_id();
+
+ __flush_tlb_all();
+ if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_LAZY)
+ leave_mm(cpu);
+}
+
+void flush_tlb_all(void)
+{
+ on_each_cpu(do_flush_tlb_all, NULL, 1, 1);
+}
+
+/*
+ * 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 ...
+ */
+static void native_smp_send_reschedule(int cpu)
+{
+ WARN_ON(cpu_is_offline(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;
+};
+
+void lock_ipi_call_lock(void)
+{
+ spin_lock_irq(&call_lock);
+}
+
+void unlock_ipi_call_lock(void)
+{
+ spin_unlock_irq(&call_lock);
+}
+
+static struct call_data_struct *call_data;
+
+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;
+ mb();
+
+ /* 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)
+ while (atomic_read(&data.finished) != cpus)
+ cpu_relax();
+}
+
+
+/**
+ * smp_call_function_mask(): Run a function on a set of other CPUs.
+ * @mask: The set of cpus to run on. Must not include the current cpu.
+ * @func: The function to run. This must be fast and non-blocking.
+ * @info: An arbitrary pointer to pass to the function.
+ * @wait: If true, wait (atomically) until function has completed on other CPUs.
+ *
+ * Returns 0 on success, else a negative status code.
+ *
+ * If @wait is true, then returns once @func has returned; otherwise
+ * it returns just before the target cpu calls @func.
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler.
+ */
+static int
+native_smp_call_function_mask(cpumask_t mask,
+ void (*func)(void *), void *info,
+ int wait)
+{
+ struct call_data_struct data;
+ cpumask_t allbutself;
+ int cpus;
+
+ /* Can deadlock when called with interrupts disabled */
+ WARN_ON(irqs_disabled());
+
+ /* Holding any lock stops cpus from going down. */
+ spin_lock(&call_lock);
+
+ allbutself = cpu_online_map;
+ cpu_clear(smp_processor_id(), allbutself);
+
+ cpus_and(mask, mask, allbutself);
+ cpus = cpus_weight(mask);
+
+ if (!cpus) {
+ spin_unlock(&call_lock);
+ return 0;
+ }
+
+ data.func = func;
+ data.info = info;
+ atomic_set(&data.started, 0);
+ data.wait = wait;
+ if (wait)
+ atomic_set(&data.finished, 0);
+
+ call_data = &data;
+ mb();
+
+ /* Send a message to other CPUs */
+ if (cpus_equal(mask, allbutself))
+ send_IPI_allbutself(CALL_FUNCTION_VECTOR);
+ else
+ send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
+
+ /* Wait for response */
+ while (atomic_read(&data.started) != cpus)
+ cpu_relax();
+
+ if (wait)
+ while (atomic_read(&data.finished) != cpus)
+ cpu_relax();
+ spin_unlock(&call_lock);
+
+ return 0;
+}
+
+static void stop_this_cpu (void * dummy)
+{
+ local_irq_disable();
+ /*
+ * Remove this CPU:
+ */
+ cpu_clear(smp_processor_id(), cpu_online_map);
+ disable_local_APIC();
+ if (cpu_data[smp_processor_id()].hlt_works_ok)
+ for(;;) halt();
+ for (;;);
+}
+
+/*
+ * this function calls the 'stop' function on all other CPUs in the system.
+ */
+
+static void native_smp_send_stop(void)
+{
+ /* Don't deadlock on the call lock in panic */
+ int nolock = !spin_trylock(&call_lock);
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __smp_call_function(stop_this_cpu, NULL, 0, 0);
+ if (!nolock)
+ spin_unlock(&call_lock);
+ disable_local_APIC();
+ local_irq_restore(flags);
+}
+
+/*
+ * Reschedule call back. Nothing to do,
+ * all the work is done automatically when
+ * we return from the interrupt.
+ */
+fastcall void smp_reschedule_interrupt(struct pt_regs *regs)
+{
+ ack_APIC_irq();
+}
+
+fastcall void smp_call_function_interrupt(struct pt_regs *regs)
+{
+ 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);
+ }
+}
+
+static int convert_apicid_to_cpu(int apic_id)
+{
+ int i;
+
+ for (i = 0; i < NR_CPUS; i++) {
+ if (x86_cpu_to_apicid[i] == apic_id)
+ return i;
+ }
+ return -1;
+}
+
+int safe_smp_processor_id(void)
+{
+ int apicid, cpuid;
+
+ if (!boot_cpu_has(X86_FEATURE_APIC))
+ return 0;
+
+ apicid = hard_smp_processor_id();
+ if (apicid == BAD_APICID)
+ return 0;
+
+ cpuid = convert_apicid_to_cpu(apicid);
+
+ return cpuid >= 0 ? cpuid : 0;
+}
+
+struct smp_ops smp_ops = {
+ .smp_prepare_boot_cpu = native_smp_prepare_boot_cpu,
+ .smp_prepare_cpus = native_smp_prepare_cpus,
+ .cpu_up = native_cpu_up,
+ .smp_cpus_done = native_smp_cpus_done,
+
+ .smp_send_stop = native_smp_send_stop,
+ .smp_send_reschedule = native_smp_send_reschedule,
+ .smp_call_function_mask = native_smp_call_function_mask,
+};
projects / deliverable / linux.git / commitdiff
