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-rw-r--r--arch/x86/kernel/apic/Makefile4
-rw-r--r--arch/x86/kernel/apic/apic.c16
-rw-r--r--arch/x86/kernel/apic/apic_flat_64.c2
-rw-r--r--arch/x86/kernel/apic/apic_numachip.c4
-rw-r--r--arch/x86/kernel/apic/ipi.c60
-rw-r--r--arch/x86/kernel/apic/vector.c88
-rw-r--r--arch/x86/kernel/apic/x2apic_uv_x.c5
7 files changed, 155 insertions, 24 deletions
diff --git a/arch/x86/kernel/apic/Makefile b/arch/x86/kernel/apic/Makefile
index 8bb12ddc5db8..8e63ebdcbd0b 100644
--- a/arch/x86/kernel/apic/Makefile
+++ b/arch/x86/kernel/apic/Makefile
@@ -2,6 +2,10 @@
# Makefile for local APIC drivers and for the IO-APIC code
#
+# Leads to non-deterministic coverage that is not a function of syscall inputs.
+# In particualr, smp_apic_timer_interrupt() is called in random places.
+KCOV_INSTRUMENT := n
+
obj-$(CONFIG_X86_LOCAL_APIC) += apic.o apic_noop.o ipi.o vector.o
obj-y += hw_nmi.o
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 8a5cddac7d44..d356987a04e9 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1611,7 +1611,7 @@ void __init enable_IR_x2apic(void)
legacy_pic->mask_all();
mask_ioapic_entries();
- /* If irq_remapping_prepare() succeded, try to enable it */
+ /* If irq_remapping_prepare() succeeded, try to enable it */
if (ir_stat >= 0)
ir_stat = try_to_enable_IR();
/* ir_stat contains the remap mode or an error code */
@@ -2078,6 +2078,20 @@ int generic_processor_info(int apicid, int version)
cpu = cpumask_next_zero(-1, cpu_present_mask);
/*
+ * This can happen on physical hotplug. The sanity check at boot time
+ * is done from native_smp_prepare_cpus() after num_possible_cpus() is
+ * established.
+ */
+ if (topology_update_package_map(apicid, cpu) < 0) {
+ int thiscpu = max + disabled_cpus;
+
+ pr_warning("ACPI: Package limit reached. Processor %d/0x%x ignored.\n",
+ thiscpu, apicid);
+ disabled_cpus++;
+ return -ENOSPC;
+ }
+
+ /*
* Validate version
*/
if (version == 0x0) {
diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index 9968f30cca3e..76f89e2b245a 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -53,7 +53,7 @@ void flat_init_apic_ldr(void)
apic_write(APIC_LDR, val);
}
-static inline void _flat_send_IPI_mask(unsigned long mask, int vector)
+static void _flat_send_IPI_mask(unsigned long mask, int vector)
{
unsigned long flags;
diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index c80c02c6ec49..ab5c2c685a3c 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -30,7 +30,7 @@ static unsigned int numachip1_get_apic_id(unsigned long x)
unsigned long value;
unsigned int id = (x >> 24) & 0xff;
- if (static_cpu_has_safe(X86_FEATURE_NODEID_MSR)) {
+ if (static_cpu_has(X86_FEATURE_NODEID_MSR)) {
rdmsrl(MSR_FAM10H_NODE_ID, value);
id |= (value << 2) & 0xff00;
}
@@ -178,7 +178,7 @@ static void fixup_cpu_id(struct cpuinfo_x86 *c, int node)
this_cpu_write(cpu_llc_id, node);
/* Account for nodes per socket in multi-core-module processors */
- if (static_cpu_has_safe(X86_FEATURE_NODEID_MSR)) {
+ if (static_cpu_has(X86_FEATURE_NODEID_MSR)) {
rdmsrl(MSR_FAM10H_NODE_ID, val);
nodes = ((val >> 3) & 7) + 1;
}
diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index eb45fc9b6124..28bde88b0085 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -18,6 +18,66 @@
#include <asm/proto.h>
#include <asm/ipi.h>
+void __default_send_IPI_shortcut(unsigned int shortcut, int vector, unsigned int dest)
+{
+ /*
+ * 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.
+ */
+ __xapic_wait_icr_idle();
+
+ /*
+ * No need to touch the target chip field
+ */
+ cfg = __prepare_ICR(shortcut, vector, dest);
+
+ /*
+ * Send the IPI. The write to APIC_ICR fires this off.
+ */
+ native_apic_mem_write(APIC_ICR, cfg);
+}
+
+/*
+ * This is used to send an IPI with no shorthand notation (the destination is
+ * specified in bits 56 to 63 of the ICR).
+ */
+void __default_send_IPI_dest_field(unsigned int mask, int vector, unsigned int dest)
+{
+ unsigned long cfg;
+
+ /*
+ * Wait for idle.
+ */
+ if (unlikely(vector == NMI_VECTOR))
+ safe_apic_wait_icr_idle();
+ else
+ __xapic_wait_icr_idle();
+
+ /*
+ * prepare target chip field
+ */
+ cfg = __prepare_ICR2(mask);
+ native_apic_mem_write(APIC_ICR2, cfg);
+
+ /*
+ * program the ICR
+ */
+ cfg = __prepare_ICR(0, vector, dest);
+
+ /*
+ * Send the IPI. The write to APIC_ICR fires this off.
+ */
+ native_apic_mem_write(APIC_ICR, cfg);
+}
+
void default_send_IPI_single_phys(int cpu, int vector)
{
unsigned long flags;
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 3b670df4ba7b..ad59d70bcb1a 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -213,6 +213,7 @@ update:
*/
cpumask_and(d->old_domain, d->old_domain, cpu_online_mask);
d->move_in_progress = !cpumask_empty(d->old_domain);
+ d->cfg.old_vector = d->move_in_progress ? d->cfg.vector : 0;
d->cfg.vector = vector;
cpumask_copy(d->domain, vector_cpumask);
success:
@@ -655,46 +656,97 @@ void irq_complete_move(struct irq_cfg *cfg)
}
/*
- * Called with @desc->lock held and interrupts disabled.
+ * Called from fixup_irqs() with @desc->lock held and interrupts disabled.
*/
void irq_force_complete_move(struct irq_desc *desc)
{
struct irq_data *irqdata = irq_desc_get_irq_data(desc);
struct apic_chip_data *data = apic_chip_data(irqdata);
struct irq_cfg *cfg = data ? &data->cfg : NULL;
+ unsigned int cpu;
if (!cfg)
return;
- __irq_complete_move(cfg, cfg->vector);
-
/*
* This is tricky. If the cleanup of @data->old_domain has not been
* done yet, then the following setaffinity call will fail with
* -EBUSY. This can leave the interrupt in a stale state.
*
- * The cleanup cannot make progress because we hold @desc->lock. So in
- * case @data->old_domain is not yet cleaned up, we need to drop the
- * lock and acquire it again. @desc cannot go away, because the
- * hotplug code holds the sparse irq lock.
+ * All CPUs are stuck in stop machine with interrupts disabled so
+ * calling __irq_complete_move() would be completely pointless.
*/
raw_spin_lock(&vector_lock);
- /* Clean out all offline cpus (including ourself) first. */
+ /*
+ * Clean out all offline cpus (including the outgoing one) from the
+ * old_domain mask.
+ */
cpumask_and(data->old_domain, data->old_domain, cpu_online_mask);
- while (!cpumask_empty(data->old_domain)) {
+
+ /*
+ * If move_in_progress is cleared and the old_domain mask is empty,
+ * then there is nothing to cleanup. fixup_irqs() will take care of
+ * the stale vectors on the outgoing cpu.
+ */
+ if (!data->move_in_progress && cpumask_empty(data->old_domain)) {
raw_spin_unlock(&vector_lock);
- raw_spin_unlock(&desc->lock);
- cpu_relax();
- raw_spin_lock(&desc->lock);
+ return;
+ }
+
+ /*
+ * 1) The interrupt is in move_in_progress state. That means that we
+ * have not seen an interrupt since the io_apic was reprogrammed to
+ * the new vector.
+ *
+ * 2) The interrupt has fired on the new vector, but the cleanup IPIs
+ * have not been processed yet.
+ */
+ if (data->move_in_progress) {
/*
- * Reevaluate apic_chip_data. It might have been cleared after
- * we dropped @desc->lock.
+ * In theory there is a race:
+ *
+ * set_ioapic(new_vector) <-- Interrupt is raised before update
+ * is effective, i.e. it's raised on
+ * the old vector.
+ *
+ * So if the target cpu cannot handle that interrupt before
+ * the old vector is cleaned up, we get a spurious interrupt
+ * and in the worst case the ioapic irq line becomes stale.
+ *
+ * But in case of cpu hotplug this should be a non issue
+ * because if the affinity update happens right before all
+ * cpus rendevouz in stop machine, there is no way that the
+ * interrupt can be blocked on the target cpu because all cpus
+ * loops first with interrupts enabled in stop machine, so the
+ * old vector is not yet cleaned up when the interrupt fires.
+ *
+ * So the only way to run into this issue is if the delivery
+ * of the interrupt on the apic/system bus would be delayed
+ * beyond the point where the target cpu disables interrupts
+ * in stop machine. I doubt that it can happen, but at least
+ * there is a theroretical chance. Virtualization might be
+ * able to expose this, but AFAICT the IOAPIC emulation is not
+ * as stupid as the real hardware.
+ *
+ * Anyway, there is nothing we can do about that at this point
+ * w/o refactoring the whole fixup_irq() business completely.
+ * We print at least the irq number and the old vector number,
+ * so we have the necessary information when a problem in that
+ * area arises.
*/
- data = apic_chip_data(irqdata);
- if (!data)
- return;
- raw_spin_lock(&vector_lock);
+ pr_warn("IRQ fixup: irq %d move in progress, old vector %d\n",
+ irqdata->irq, cfg->old_vector);
}
+ /*
+ * If old_domain is not empty, then other cpus still have the irq
+ * descriptor set in their vector array. Clean it up.
+ */
+ for_each_cpu(cpu, data->old_domain)
+ per_cpu(vector_irq, cpu)[cfg->old_vector] = VECTOR_UNUSED;
+
+ /* Cleanup the left overs of the (half finished) move */
+ cpumask_clear(data->old_domain);
+ data->move_in_progress = 0;
raw_spin_unlock(&vector_lock);
}
#endif
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 624db00583f4..8f4942e2bcbb 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -792,7 +792,8 @@ static int uv_scir_cpu_notify(struct notifier_block *self, unsigned long action,
{
long cpu = (long)hcpu;
- switch (action) {
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_DOWN_FAILED:
case CPU_ONLINE:
uv_heartbeat_enable(cpu);
break;
@@ -860,7 +861,7 @@ int uv_set_vga_state(struct pci_dev *pdev, bool decode,
*/
void uv_cpu_init(void)
{
- /* CPU 0 initilization will be done via uv_system_init. */
+ /* CPU 0 initialization will be done via uv_system_init. */
if (!uv_blade_info)
return;