[PATCH v5 RESEND 4/5] x86, acpi, cpu-hotplug: Enable MADT APIs to return disabled apicid.

From: Tang Chen
Date: Mon Jan 25 2016 - 01:08:52 EST


From: Gu Zheng <guz.fnst@xxxxxxxxxxxxxx>

The whole patch-set aims at making cpuid <-> nodeid mapping persistent. So that,
when node online/offline happens, cache based on cpuid <-> nodeid mapping such as
wq_numa_possible_cpumask will not cause any problem.
It contains 4 steps:
1. Enable apic registeration flow to handle both enabled and disabled cpus.
2. Introduce a new array storing all possible cpuid <-> apicid mapping.
3. Enable _MAT and MADT relative apis to return non-presnet or disabled cpus' apicid.
4. Establish all possible cpuid <-> nodeid mapping.

This patch finishes step 3.

There are four mappings in the kernel:
1. nodeid (logical node id) <-> pxm (persistent)
2. apicid (physical cpu id) <-> nodeid (persistent)
3. cpuid (logical cpu id) <-> apicid (not persistent, now persistent by step 2)
4. cpuid (logical cpu id) <-> nodeid (not persistent)

So, in order to setup persistent cpuid <-> nodeid mapping for all possible CPUs,
we should:
1. Setup cpuid <-> apicid mapping for all possible CPUs, which has been done in step 1, 2.
2. Setup cpuid <-> nodeid mapping for all possible CPUs. But before that, we should
obtain all apicids from MADT.

All processors' apicids can be obtained by _MAT method or from MADT in ACPI.
The current code ignores disabled processors and returns -ENODEV.

After this patch, a new parameter will be added to MADT APIs so that caller
is able to control if disabled processors are ignored.

Signed-off-by: Gu Zheng <guz.fnst@xxxxxxxxxxxxxx>
Signed-off-by: Tang Chen <tangchen@xxxxxxxxxxxxxx>
---
drivers/acpi/acpi_processor.c | 5 +++-
drivers/acpi/processor_core.c | 57 +++++++++++++++++++++++++++----------------
2 files changed, 40 insertions(+), 22 deletions(-)

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 6979186..d30111a 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -300,8 +300,11 @@ static int acpi_processor_get_info(struct acpi_device *device)
* Extra Processor objects may be enumerated on MP systems with
* less than the max # of CPUs. They should be ignored _iff
* they are physically not present.
+ *
+ * NOTE: Even if the processor has a cpuid, it may not present because
+ * cpuid <-> apicid mapping is persistent now.
*/
- if (invalid_logical_cpuid(pr->id)) {
+ if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
int ret = acpi_processor_hotadd_init(pr);
if (ret)
return ret;
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 33a38d6..824b98b 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -32,12 +32,12 @@ static struct acpi_table_madt *get_madt_table(void)
}

static int map_lapic_id(struct acpi_subtable_header *entry,
- u32 acpi_id, phys_cpuid_t *apic_id)
+ u32 acpi_id, phys_cpuid_t *apic_id, bool ignore_disabled)
{
struct acpi_madt_local_apic *lapic =
container_of(entry, struct acpi_madt_local_apic, header);

- if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(lapic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;

if (lapic->processor_id != acpi_id)
@@ -48,12 +48,13 @@ static int map_lapic_id(struct acpi_subtable_header *entry,
}

static int map_x2apic_id(struct acpi_subtable_header *entry,
- int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
+ int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id,
+ bool ignore_disabled)
{
struct acpi_madt_local_x2apic *apic =
container_of(entry, struct acpi_madt_local_x2apic, header);

- if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(apic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;

if (device_declaration && (apic->uid == acpi_id)) {
@@ -65,12 +66,13 @@ static int map_x2apic_id(struct acpi_subtable_header *entry,
}

static int map_lsapic_id(struct acpi_subtable_header *entry,
- int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
+ int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id,
+ bool ignore_disabled)
{
struct acpi_madt_local_sapic *lsapic =
container_of(entry, struct acpi_madt_local_sapic, header);

- if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(lsapic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;

if (device_declaration) {
@@ -87,12 +89,13 @@ static int map_lsapic_id(struct acpi_subtable_header *entry,
* Retrieve the ARM CPU physical identifier (MPIDR)
*/
static int map_gicc_mpidr(struct acpi_subtable_header *entry,
- int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
+ int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr,
+ bool ignore_disabled)
{
struct acpi_madt_generic_interrupt *gicc =
container_of(entry, struct acpi_madt_generic_interrupt, header);

- if (!(gicc->flags & ACPI_MADT_ENABLED))
+ if (ignore_disabled && !(gicc->flags & ACPI_MADT_ENABLED))
return -ENODEV;

/* device_declaration means Device object in DSDT, in the
@@ -108,7 +111,7 @@ static int map_gicc_mpidr(struct acpi_subtable_header *entry,
return -EINVAL;
}

-static phys_cpuid_t map_madt_entry(int type, u32 acpi_id)
+static phys_cpuid_t map_madt_entry(int type, u32 acpi_id, bool ignore_disabled)
{
unsigned long madt_end, entry;
phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */
@@ -128,16 +131,20 @@ static phys_cpuid_t map_madt_entry(int type, u32 acpi_id)
struct acpi_subtable_header *header =
(struct acpi_subtable_header *)entry;
if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
- if (!map_lapic_id(header, acpi_id, &phys_id))
+ if (!map_lapic_id(header, acpi_id, &phys_id,
+ ignore_disabled))
break;
} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
- if (!map_x2apic_id(header, type, acpi_id, &phys_id))
+ if (!map_x2apic_id(header, type, acpi_id, &phys_id,
+ ignore_disabled))
break;
} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
- if (!map_lsapic_id(header, type, acpi_id, &phys_id))
+ if (!map_lsapic_id(header, type, acpi_id, &phys_id,
+ ignore_disabled))
break;
} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
- if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
+ if (!map_gicc_mpidr(header, type, acpi_id, &phys_id,
+ ignore_disabled))
break;
}
entry += header->length;
@@ -145,7 +152,8 @@ static phys_cpuid_t map_madt_entry(int type, u32 acpi_id)
return phys_id;
}

-static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
+static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id,
+ bool ignore_disabled)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
@@ -166,30 +174,37 @@ static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)

header = (struct acpi_subtable_header *)obj->buffer.pointer;
if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
- map_lapic_id(header, acpi_id, &phys_id);
+ map_lapic_id(header, acpi_id, &phys_id, ignore_disabled);
else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
- map_lsapic_id(header, type, acpi_id, &phys_id);
+ map_lsapic_id(header, type, acpi_id, &phys_id, ignore_disabled);
else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
- map_x2apic_id(header, type, acpi_id, &phys_id);
+ map_x2apic_id(header, type, acpi_id, &phys_id, ignore_disabled);
else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
- map_gicc_mpidr(header, type, acpi_id, &phys_id);
+ map_gicc_mpidr(header, type, acpi_id, &phys_id,
+ ignore_disabled);

exit:
kfree(buffer.pointer);
return phys_id;
}

-phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
+static phys_cpuid_t __acpi_get_phys_id(acpi_handle handle, int type,
+ u32 acpi_id, bool ignore_disabled)
{
phys_cpuid_t phys_id;

- phys_id = map_mat_entry(handle, type, acpi_id);
+ phys_id = map_mat_entry(handle, type, acpi_id, ignore_disabled);
if (invalid_phys_cpuid(phys_id))
- phys_id = map_madt_entry(type, acpi_id);
+ phys_id = map_madt_entry(type, acpi_id, ignore_disabled);

return phys_id;
}

+phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
+{
+ return __acpi_get_phys_id(handle, type, acpi_id, true);
+}
+
int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
{
#ifdef CONFIG_SMP
--
1.9.3