Adds various utility functions which might be required to fetch or check the
state of the possible vCPUs. This also introduces concept of *disabled* vCPUs,
which are part of the *possible* vCPUs but are not part of the *present* vCPU.
This state shall be used during machine init time to check the presence of
vcpus.
Co-developed-by: Salil Mehta <salil.me...@huawei.com>
Signed-off-by: Salil Mehta <salil.me...@huawei.com>
Co-developed-by: Keqian Zhu <zhukeqi...@huawei.com>
Signed-off-by: Keqian Zhu <zhukeqi...@huawei.com>
Signed-off-by: Salil Mehta <salil.me...@huawei.com>
---
cpus-common.c | 31 +++++++++++++++++++++++++
include/hw/core/cpu.h | 53 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 84 insertions(+)
diff --git a/cpus-common.c b/cpus-common.c
index 45c745ecf6..24c04199a1 100644
--- a/cpus-common.c
+++ b/cpus-common.c
@@ -24,6 +24,7 @@
#include "sysemu/cpus.h"
#include "qemu/lockable.h"
#include "trace/trace-root.h"
+#include "hw/boards.h"
QemuMutex qemu_cpu_list_lock;
static QemuCond exclusive_cond;
@@ -107,6 +108,36 @@ void cpu_list_remove(CPUState *cpu)
cpu_list_generation_id++;
}
+CPUState *qemu_get_possible_cpu(int index)
+{
+ MachineState *ms = MACHINE(qdev_get_machine());
+ const CPUArchIdList *possible_cpus = ms->possible_cpus;
+
+ assert((index >= 0) && (index < possible_cpus->len));
+
+ return CPU(possible_cpus->cpus[index].cpu);
+}
+
+bool qemu_present_cpu(CPUState *cpu)
+{
+ return cpu;
+}
+
+bool qemu_enabled_cpu(CPUState *cpu)
+{
+ return cpu && !cpu->disabled;
+}
+
+uint64_t qemu_get_cpu_archid(int cpu_index)
+{
+ MachineState *ms = MACHINE(qdev_get_machine());
+ const CPUArchIdList *possible_cpus = ms->possible_cpus;
+
+ assert((cpu_index >= 0) && (cpu_index < possible_cpus->len));
+
+ return possible_cpus->cpus[cpu_index].arch_id;
+}
+
CPUState *qemu_get_cpu(int index)
{
CPUState *cpu;
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index fdcbe87352..e5af79950c 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -413,6 +413,17 @@ struct CPUState {
SavedIOTLB saved_iotlb;
#endif
+ /*
+ * Some architectures do not allow *presence* of vCPUs to be changed
+ * after guest has booted using information specified by VMM/firmware
+ * via ACPI MADT at the boot time. Thus to enable vCPU hotplug on these
+ * architectures possible vCPU can have CPUState object in 'disabled'
+ * state or can also not have CPUState object at all. This is possible
+ * when vCPU Hotplug is supported and vCPUs are 'yet-to-be-plugged' in
+ * the QOM or have been hot-unplugged.
+ * By default every CPUState is enabled as of now across all archs.
+ */
+ bool disabled;
/* TODO Move common fields from CPUArchState here. */
int cpu_index;
int cluster_index;
@@ -770,6 +781,48 @@ static inline bool cpu_in_exclusive_context(const CPUState
*cpu)
*/
CPUState *qemu_get_cpu(int index);
+/**
+ * qemu_get_possible_cpu:
+ * @index: The CPUState@cpu_index value of the CPU to obtain.
+ * Input index MUST be in range [0, Max Possible CPUs)
+ *
+ * If CPUState object exists,then it gets a CPU matching
+ * @index in the possible CPU array.
+ *
+ * Returns: The possible CPU or %NULL if CPU does not exist.
+ */
+CPUState *qemu_get_possible_cpu(int index);
+
+/**
+ * qemu_present_cpu:
+ * @cpu: The vCPU to check
+ *
+ * Checks if the vCPU is amongst the present possible vcpus.
+ *
+ * Returns: True if it is present possible vCPU else false
+ */
+bool qemu_present_cpu(CPUState *cpu);
+
+/**
+ * qemu_enabled_cpu:
+ * @cpu: The vCPU to check
+ *
+ * Checks if the vCPU is enabled.
+ *
+ * Returns: True if it is 'enabled' else false
+ */
+bool qemu_enabled_cpu(CPUState *cpu);
+
+/**
+ * qemu_get_cpu_archid:
+ * @cpu_index: possible vCPU for which arch-id needs to be retreived
+ *
+ * Fetches the vCPU arch-id from the present possible vCPUs.
+ *
+ * Returns: arch-id of the possible vCPU
+ */
+uint64_t qemu_get_cpu_archid(int cpu_index);
+
/**
* cpu_exists:
* @id: Guest-exposed CPU ID to lookup.
--
2.34.1
