xref: /linux/include/xen/interface/sched.h (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /******************************************************************************
2  * sched.h
3  *
4  * Scheduler state interactions
5  *
6  * Copyright (c) 2005, Keir Fraser <keir@xensource.com>
7  */
8 
9 #ifndef __XEN_PUBLIC_SCHED_H__
10 #define __XEN_PUBLIC_SCHED_H__
11 
12 #include <xen/interface/event_channel.h>
13 
14 /*
15  * The prototype for this hypercall is:
16  *  long sched_op_new(int cmd, void *arg)
17  * @cmd == SCHEDOP_??? (scheduler operation).
18  * @arg == Operation-specific extra argument(s), as described below.
19  *
20  * **NOTE**:
21  * Versions of Xen prior to 3.0.2 provide only the following legacy version
22  * of this hypercall, supporting only the commands yield, block and shutdown:
23  *  long sched_op(int cmd, unsigned long arg)
24  * @cmd == SCHEDOP_??? (scheduler operation).
25  * @arg == 0               (SCHEDOP_yield and SCHEDOP_block)
26  *      == SHUTDOWN_* code (SCHEDOP_shutdown)
27  */
28 
29 /*
30  * Voluntarily yield the CPU.
31  * @arg == NULL.
32  */
33 #define SCHEDOP_yield       0
34 
35 /*
36  * Block execution of this VCPU until an event is received for processing.
37  * If called with event upcalls masked, this operation will atomically
38  * reenable event delivery and check for pending events before blocking the
39  * VCPU. This avoids a "wakeup waiting" race.
40  * @arg == NULL.
41  */
42 #define SCHEDOP_block       1
43 
44 /*
45  * Halt execution of this domain (all VCPUs) and notify the system controller.
46  * @arg == pointer to sched_shutdown structure.
47  */
48 #define SCHEDOP_shutdown    2
49 struct sched_shutdown {
50     unsigned int reason; /* SHUTDOWN_* */
51 };
52 DEFINE_GUEST_HANDLE_STRUCT(sched_shutdown);
53 
54 /*
55  * Poll a set of event-channel ports. Return when one or more are pending. An
56  * optional timeout may be specified.
57  * @arg == pointer to sched_poll structure.
58  */
59 #define SCHEDOP_poll        3
60 struct sched_poll {
61     GUEST_HANDLE(evtchn_port_t) ports;
62     unsigned int nr_ports;
63     uint64_t timeout;
64 };
65 DEFINE_GUEST_HANDLE_STRUCT(sched_poll);
66 
67 /*
68  * Declare a shutdown for another domain. The main use of this function is
69  * in interpreting shutdown requests and reasons for fully-virtualized
70  * domains.  A para-virtualized domain may use SCHEDOP_shutdown directly.
71  * @arg == pointer to sched_remote_shutdown structure.
72  */
73 #define SCHEDOP_remote_shutdown        4
74 struct sched_remote_shutdown {
75     domid_t domain_id;         /* Remote domain ID */
76     unsigned int reason;       /* SHUTDOWN_xxx reason */
77 };
78 
79 /*
80  * Latch a shutdown code, so that when the domain later shuts down it
81  * reports this code to the control tools.
82  * @arg == as for SCHEDOP_shutdown.
83  */
84 #define SCHEDOP_shutdown_code 5
85 
86 /*
87  * Setup, poke and destroy a domain watchdog timer.
88  * @arg == pointer to sched_watchdog structure.
89  * With id == 0, setup a domain watchdog timer to cause domain shutdown
90  *               after timeout, returns watchdog id.
91  * With id != 0 and timeout == 0, destroy domain watchdog timer.
92  * With id != 0 and timeout != 0, poke watchdog timer and set new timeout.
93  */
94 #define SCHEDOP_watchdog    6
95 struct sched_watchdog {
96     uint32_t id;                /* watchdog ID */
97     uint32_t timeout;           /* timeout */
98 };
99 
100 /*
101  * Reason codes for SCHEDOP_shutdown. These may be interpreted by control
102  * software to determine the appropriate action. For the most part, Xen does
103  * not care about the shutdown code.
104  */
105 #define SHUTDOWN_poweroff   0  /* Domain exited normally. Clean up and kill. */
106 #define SHUTDOWN_reboot     1  /* Clean up, kill, and then restart.          */
107 #define SHUTDOWN_suspend    2  /* Clean up, save suspend info, kill.         */
108 #define SHUTDOWN_crash      3  /* Tell controller we've crashed.             */
109 #define SHUTDOWN_watchdog   4  /* Restart because watchdog time expired.     */
110 
111 #endif /* __XEN_PUBLIC_SCHED_H__ */
112