[PATCH v8 4/7] x86, acpi, cpu-hotplug: Enable MADT APIs to return disabled apicid.

[Dou Liyang]

From: Gu Zheng 

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 
Signed-off-by: Tang Chen 
Signed-off-by: Zhu Guihua 
Signed-off-by: Dou Liyang 
---
 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 c7ba948..e85b19a 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 

[PATCH v8 4/7] x86, acpi, cpu-hotplug: Enable MADT APIs to return disabled apicid.

[Dou Liyang]

From: Gu Zheng 

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 
Signed-off-by: Tang Chen 
Signed-off-by: Zhu Guihua 
Signed-off-by: Dou Liyang 
---
 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 c7ba948..e85b19a 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)
+