[patch 36/52] x86/irq/vector: Initialize matrix allocator

Thomas Gleixner
2017-09-13T21:35:16Z

[-- Attachment #1: x86-irq-vector--Initialize-matrix-allocator.patch --]
[-- Type: text/plain, Size: 7036 bytes --]

Initialize the matrix allocator and add the proper accounting points to the
code.

No functional change, just preparation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/Kconfig | 1
arch/x86/include/asm/apic.h | 6 ++++
arch/x86/include/asm/hw_irq.h | 3 +-
arch/x86/kernel/apic/vector.c | 56 +++++++++++++++++++++++++++++++++++++++---
arch/x86/kernel/i8259.c | 1
arch/x86/kernel/irqinit.c | 1
arch/x86/kernel/smpboot.c | 3 +-
7 files changed, 65 insertions(+), 6 deletions(-)

Index: b/arch/x86/Kconfig
===================================================================
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -93,6 +93,7 @@ config X86
select GENERIC_FIND_FIRST_BIT
select GENERIC_IOMAP
select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
+ select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
select GENERIC_IRQ_MIGRATION if SMP
select GENERIC_IRQ_PROBE
select GENERIC_IRQ_SHOW
Index: b/arch/x86/include/asm/apic.h
===================================================================
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -161,6 +161,10 @@ static inline int apic_is_clustered_box(
#endif

extern int setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask);
+extern void lapic_assign_system_vectors(void);
+extern void lapic_assign_legacy_vector(unsigned int isairq, bool replace);
+extern void lapic_online(void);
+extern void lapic_offline(void);

#else /* !CONFIG_X86_LOCAL_APIC */
static inline void lapic_shutdown(void) { }
@@ -170,6 +174,8 @@ static inline void disable_local_APIC(vo
# define setup_boot_APIC_clock x86_init_noop
# define setup_secondary_APIC_clock x86_init_noop
static inline void lapic_update_tsc_freq(void) { }
+static inline void lapic_assign_system_vectors(void) { }
+static inline void lapic_assign_legacy_vector(unsigned int i, bool r) { }
#endif /* !CONFIG_X86_LOCAL_APIC */

#ifdef CONFIG_X86_X2APIC
Index: b/arch/x86/include/asm/hw_irq.h
===================================================================
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -15,6 +15,8 @@

#include <asm/irq_vectors.h>

+#define IRQ_MATRIX_BITS NR_VECTORS
+
#ifndef __ASSEMBLY__

#include <linux/percpu.h>
@@ -130,7 +132,6 @@ extern struct irq_cfg *irq_cfg(unsigned
extern struct irq_cfg *irqd_cfg(struct irq_data *irq_data);
extern void lock_vector_lock(void);
extern void unlock_vector_lock(void);
-extern void setup_vector_irq(int cpu);
#ifdef CONFIG_SMP
extern void send_cleanup_vector(struct irq_cfg *);
extern void irq_complete_move(struct irq_cfg *cfg);
Index: b/arch/x86/kernel/apic/vector.c
===================================================================
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -36,6 +36,7 @@ EXPORT_SYMBOL_GPL(x86_vector_domain);
static DEFINE_RAW_SPINLOCK(vector_lock);
static cpumask_var_t vector_cpumask, vector_searchmask, searched_cpumask;
static struct irq_chip lapic_controller;
+static struct irq_matrix *vector_matrix;
#ifdef CONFIG_SMP
static DEFINE_PER_CPU(struct hlist_head, cleanup_list);
#endif
@@ -404,6 +405,36 @@ int __init arch_probe_nr_irqs(void)
return legacy_pic->probe();
}

+void lapic_assign_legacy_vector(unsigned int irq, bool replace)
+{
+ /*
+ * Use assign system here so it wont get accounted as allocated
+ * and moveable in the cpu hotplug check and it prevents managed
+ * irq reservation from touching it.
+ */
+ irq_matrix_assign_system(vector_matrix, ISA_IRQ_VECTOR(irq), replace);
+}
+
+void __init lapic_assign_system_vectors(void)
+{
+ unsigned int i, vector = 0;
+
+ for_each_set_bit_from(vector, system_vectors, NR_VECTORS)
+ irq_matrix_assign_system(vector_matrix, vector, false);
+
+ if (nr_legacy_irqs() > 1)
+ lapic_assign_legacy_vector(PIC_CASCADE_IR, false);
+
+ /* System vectors are reserved, online it */
+ irq_matrix_online(vector_matrix);
+
+ /* Mark the preallocated legacy interrupts */
+ for (i = 0; i < nr_legacy_irqs(); i++) {
+ if (i != PIC_CASCADE_IR)
+ irq_matrix_assign(vector_matrix, ISA_IRQ_VECTOR(i));
+ }
+}
+
int __init arch_early_irq_init(void)
{
struct fwnode_handle *fn;
@@ -423,6 +454,14 @@ int __init arch_early_irq_init(void)
BUG_ON(!alloc_cpumask_var(&vector_searchmask, GFP_KERNEL));
BUG_ON(!alloc_cpumask_var(&searched_cpumask, GFP_KERNEL));

+ /*
+ * Allocate the vector matrix allocator data structure and limit the
+ * search area.
+ */
+ vector_matrix = irq_alloc_matrix(NR_VECTORS, FIRST_EXTERNAL_VECTOR,
+ FIRST_SYSTEM_VECTOR);
+ BUG_ON(!vector_matrix);
+
return arch_early_ioapic_init();
}

@@ -454,14 +493,16 @@ static struct irq_desc *__setup_vector_i
return irq_to_desc(isairq);
}

-/*
- * Setup the vector to irq mappings. Must be called with vector_lock held.
- */
-void setup_vector_irq(int cpu)
+/* Online the local APIC infrastructure and initialize the vectors */
+void lapic_online(void)
{
unsigned int vector;

lockdep_assert_held(&vector_lock);
+
+ /* Online the vector matrix array for this CPU */
+ irq_matrix_online(vector_matrix);
+
/*
* The interrupt affinity logic never targets interrupts to offline
* CPUs. The exception are the legacy PIC interrupts. In general
@@ -482,6 +523,13 @@ void setup_vector_irq(int cpu)
vector_update_shutdown_irqs();
}

+void lapic_offline(void)
+{
+ lock_vector_lock();
+ irq_matrix_offline(vector_matrix);
+ unlock_vector_lock();
+}
+
static int apic_retrigger_irq(struct irq_data *irqd)
{
struct apic_chip_data *apicd = apic_chip_data(irqd);
Index: b/arch/x86/kernel/i8259.c
===================================================================
--- a/arch/x86/kernel/i8259.c
+++ b/arch/x86/kernel/i8259.c
@@ -113,6 +113,7 @@ static void make_8259A_irq(unsigned int
io_apic_irqs &= ~(1<<irq);
irq_set_chip_and_handler(irq, &i8259A_chip, handle_level_irq);
enable_irq(irq);
+ lapic_assign_legacy_vector(irq, true);
}

/*
Index: b/arch/x86/kernel/irqinit.c
===================================================================
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c
@@ -93,6 +93,7 @@ void __init native_init_IRQ(void)
x86_init.irqs.pre_vector_init();

idt_setup_apic_and_irq_gates();
+ lapic_assign_system_vectors();

if (!acpi_ioapic && !of_ioapic && nr_legacy_irqs())
setup_irq(2, &irq2);
Index: b/arch/x86/kernel/smpboot.c
===================================================================
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -257,7 +257,7 @@ static void notrace start_secondary(void
* from seeing a half valid vector space.
*/
lock_vector_lock();
- setup_vector_irq(smp_processor_id());
+ lapic_online();
set_cpu_online(smp_processor_id(), true);
unlock_vector_lock();
cpu_set_state_online(smp_processor_id());
@@ -1550,6 +1550,7 @@ void cpu_disable_common(void)
remove_cpu_from_maps(cpu);
unlock_vector_lock();
fixup_irqs();
+ lapic_offline();
}

int native_cpu_disable(void)