/* SPDX-License-Identifier: MIT */
/******************************************************************************
* sched.h
*
* Scheduler state interactions
*
* Copyright (c) 2005, Keir Fraser <keir@xensource.com>
*/
#ifndef __XEN_PUBLIC_SCHED_H__
#define __XEN_PUBLIC_SCHED_H__
#include "event_channel.h"
/*
* `incontents 150 sched Guest Scheduler Operations
*
* The SCHEDOP interface provides mechanisms for a guest to interact
* with the scheduler, including yield, blocking and shutting itself
* down.
*/
/*
* The prototype for this hypercall is:
* ` long HYPERVISOR_sched_op(enum sched_op cmd, void *arg, ...)
*
* @cmd == SCHEDOP_??? (scheduler operation).
* @arg == Operation-specific extra argument(s), as described below.
* ... == Additional Operation-specific extra arguments, described below.
*
* Versions of Xen prior to 3.0.2 provided only the following legacy version
* of this hypercall, supporting only the commands yield, block and shutdown:
* long sched_op(int cmd, unsigned long arg)
* @cmd == SCHEDOP_??? (scheduler operation).
* @arg == 0 (SCHEDOP_yield and SCHEDOP_block)
* == SHUTDOWN_* code (SCHEDOP_shutdown)
*
* This legacy version is available to new guests as:
* ` long HYPERVISOR_sched_op_compat(enum sched_op cmd, unsigned long arg)
*/
/* [see __HYPERVISOR_sched_op] */
/* [see __HYPERVISOR_sched_op_compat] */
/* ` enum sched_op { // SCHEDOP_* => struct sched_* */
/*
* Voluntarily yield the CPU.
* @arg == NULL.
*/
#define SCHEDOP_yield 0
/*
* Block execution of this VCPU until an event is received for processing.
* If called with event upcalls masked, this operation will atomically
* reenable event delivery and check for pending events before blocking the
* VCPU. This avoids a "wakeup waiting" race.
* @arg == NULL.
*/
#define SCHEDOP_block 1
/*
* Halt execution of this domain (all VCPUs) and notify the system controller.
* @arg == pointer to sched_shutdown_t structure.
*
* If the sched_shutdown_t reason is SHUTDOWN_suspend then
* x86 PV guests must also set RDX (EDX for 32-bit guests) to the MFN
* of the guest's start info page. RDX/EDX is the third hypercall
* argument.
*
* In addition, which reason is SHUTDOWN_suspend this hypercall
* returns 1 if suspend was cancelled or the domain was merely
* checkpointed, and 0 if it is resuming in a new domain.
*/
#define SCHEDOP_shutdown 2
/*
* Poll a set of event-channel ports. Return when one or more are pending. An
* optional timeout may be specified.
* @arg == pointer to sched_poll_t structure.
*/
#define SCHEDOP_poll 3
/*
* Declare a shutdown for another domain. The main use of this function is
* in interpreting shutdown requests and reasons for fully-virtualized
* domains. A para-virtualized domain may use SCHEDOP_shutdown directly.
* @arg == pointer to sched_remote_shutdown_t structure.
*/
#define SCHEDOP_remote_shutdown 4
/*
* Latch a shutdown code, so that when the domain later shuts down it
* reports this code to the control tools.
* @arg == sched_shutdown_t, as for SCHEDOP_shutdown.
*/
#define SCHEDOP_shutdown_code 5
/*
* Setup, poke and destroy a domain watchdog timer.
* @arg == pointer to sched_watchdog_t structure.
* With id == 0, setup a domain watchdog timer to cause domain shutdown
* after timeout, returns watchdog id.
* With id != 0 and timeout == 0, destroy domain watchdog timer.
* With id != 0 and timeout != 0, poke watchdog timer and set new timeout.
*/
#define SCHEDOP_watchdog 6
/*
* Override the current vcpu affinity by pinning it to one physical cpu or
* undo this override restoring the previous affinity.
* @arg == pointer to sched_pin_override_t structure.
*
* A negative pcpu value will undo a previous pin override and restore the
* previous cpu affinity.
* This call is allowed for the hardware domain only and requires the cpu
* to be part of the domain's cpupool.
*/
#define SCHEDOP_pin_override 7
/* ` } */
struct sched_shutdown {
unsigned int reason; /* SHUTDOWN_* => enum sched_shutdown_reason */
};
typedef struct sched_shutdown sched_shutdown_t;
DEFINE_XEN_GUEST_HANDLE(sched_shutdown_t);
/* [see SCHEDOP_shutdown] */
struct sched_poll {
XEN_GUEST_HANDLE(evtchn_port_t) ports;
unsigned int nr_ports;
uint64_t timeout;
};
typedef struct sched_poll sched_poll_t;
DEFINE_XEN_GUEST_HANDLE(sched_poll_t);
/* [see SCHEDOP_poll] */
struct sched_remote_shutdown {
domid_t domain_id; /* Remote domain ID */
unsigned int reason; /* SHUTDOWN_* => enum sched_shutdown_reason */
};
typedef struct sched_remote_shutdown sched_remote_shutdown_t;
DEFINE_XEN_GUEST_HANDLE(sched_remote_shutdown_t);
/* [see SCHEDOP_remote_shutdown] */
struct sched_watchdog {
uint32_t id; /* watchdog ID */
uint32_t timeout; /* timeout */
};
typedef struct sched_watchdog sched_watchdog_t;
DEFINE_XEN_GUEST_HANDLE(sched_watchdog_t);
/* [see SCHEDOP_watchdog] */
struct sched_pin_override {
int32_t pcpu;
};
typedef struct sched_pin_override sched_pin_override_t;
DEFINE_XEN_GUEST_HANDLE(sched_pin_override_t);
/* [see SCHEDOP_pin_override] */
/*
* Reason codes for SCHEDOP_shutdown. These may be interpreted by control
* software to determine the appropriate action. For the most part, Xen does
* not care about the shutdown code.
*/
/* ` enum sched_shutdown_reason { */
#define SHUTDOWN_poweroff 0 /* Domain exited normally. Clean up and kill. */
#define SHUTDOWN_reboot 1 /* Clean up, kill, and then restart. */
#define SHUTDOWN_suspend 2 /* Clean up, save suspend info, kill. */
#define SHUTDOWN_crash 3 /* Tell controller we've crashed. */
#define SHUTDOWN_watchdog 4 /* Restart because watchdog time expired. */
/*
* Domain asked to perform 'soft reset' for it. The expected behavior is to
* reset internal Xen state for the domain returning it to the point where it
* was created but leaving the domain's memory contents and vCPU contexts
* intact. This will allow the domain to start over and set up all Xen specific
* interfaces again.
*/
#define SHUTDOWN_soft_reset 5
#define SHUTDOWN_MAX 5 /* Maximum valid shutdown reason. */
/* ` } */
#endif /* __XEN_PUBLIC_SCHED_H__ */
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/