Skip to content
charmOS docs

IPIs

include/irq/ipi.h View source View on GitHub

Enums

Section titled “Enums”

ipi_mask_flags

Section titled “ipi_mask_flags”
enum ipi_mask_flags (2 variants) source
§ IPI_MASK_EXACT = 0

Only CPUs in the mask take the IPI

§ IPI_MASK_SUPERSET_OK = 1 << 0

Others may too

Functions

Section titled “Functions”

ipi_send

Section titled “ipi_send”
void ipi_send(cpu_id_t cpu, uint8_t vector)
source

ipi_send_try

Section titled “ipi_send_try”
bool ipi_send_try(cpu_id_t cpu, uint8_t vector)
source

Fails instead of waiting if a send is still in flight

ipi_send_cost

Section titled “ipi_send_cost”
size_t ipi_send_cost(const struct cpu_mask *targets)
source

How many IPIs does it take to bother targets?

ipi_send_mask

Section titled “ipi_send_mask”
void ipi_send_mask(
    const struct cpu_mask *targets,
    uint8_t vector,
    enum ipi_mask_flags flags
)
source

Picks shorthand / KVM PV / x2APIC cluster / physical per call

nmi_send

Section titled “nmi_send”
void nmi_send(cpu_id_t cpu)
source

nmi_send_others

Section titled “nmi_send_others”
void nmi_send_others(cpu_id_t self)
source

NMIs every CPU except self, for the panic path

Macros

Section titled “Macros”

IPI_BCAST_RATIO_Q8

Section titled “IPI_BCAST_RATIO_Q8”
#define IPI_BCAST_RATIO_Q8 (16 * 256)
source

Broadcast instead of exact if (sends_needed - 1) * 256 >= bystanders * IPI_BCAST_RATIO_Q8 where ratio is (bystander interrupt cost / cost of one send)