/******************************************************************************
* sched.h
*
* Scheduler state interactions
*
* Copyright (c) 2005, Keir Fraser <[email protected]>
*/

#ifndef __XEN_PUBLIC_SCHED_H__
#define __XEN_PUBLIC_SCHED_H__

#include <xen/interface/event_channel.h>

/*
* The prototype for this hypercall is:
* long sched_op_new(int cmd, void *arg)
* @cmd == SCHEDOP_??? (scheduler operation).
* @arg == Operation-specific extra argument(s), as described below.
*
* **NOTE**:
* Versions of Xen prior to 3.0.2 provide 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)
*/

/*
* 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 structure.
*/
#define SCHEDOP_shutdown 2
struct sched_shutdown {
unsigned int reason; /* SHUTDOWN_* */
};
DEFINE_GUEST_HANDLE_STRUCT(sched_shutdown);

/*
* 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 structure.
*/
#define SCHEDOP_poll 3
struct sched_poll {
GUEST_HANDLE(evtchn_port_t) ports;
unsigned int nr_ports;
uint64_t timeout;
};
DEFINE_GUEST_HANDLE_STRUCT(sched_poll);

/*
* 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 structure.
*/
#define SCHEDOP_remote_shutdown 4
struct sched_remote_shutdown {
domid_t domain_id; /* Remote domain ID */
unsigned int reason; /* SHUTDOWN_xxx reason */
};

/*
* Latch a shutdown code, so that when the domain later shuts down it
* reports this code to the control tools.
* @arg == as for SCHEDOP_shutdown.
*/
#define SCHEDOP_shutdown_code 5

/*
* Setup, poke and destroy a domain watchdog timer.
* @arg == pointer to sched_watchdog 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
struct sched_watchdog {
uint32_t id; /* watchdog ID */
uint32_t timeout; /* timeout */
};

/*
* 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.
*/
#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. */

#endif /* __XEN_PUBLIC_SCHED_H__ */