1/******************************************************************************
2 * sched.h
3 *
4 * Scheduler state interactions
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 *
24 * Copyright (c) 2005, Keir Fraser <keir@xensource.com>
25 */
26
27#ifndef __XEN_PUBLIC_SCHED_H__
28#define __XEN_PUBLIC_SCHED_H__
29
30#include "event_channel.h"
31
32/*
33 * `incontents 150 sched Guest Scheduler Operations
34 *
35 * The SCHEDOP interface provides mechanisms for a guest to interact
36 * with the scheduler, including yield, blocking and shutting itself
37 * down.
38 */
39
40/*
41 * The prototype for this hypercall is:
42 * ` long HYPERVISOR_sched_op(enum sched_op cmd, void *arg, ...)
43 *
44 * @cmd == SCHEDOP_??? (scheduler operation).
45 * @arg == Operation-specific extra argument(s), as described below.
46 * ...  == Additional Operation-specific extra arguments, described below.
47 *
48 * Versions of Xen prior to 3.0.2 provided only the following legacy version
49 * of this hypercall, supporting only the commands yield, block and shutdown:
50 *  long sched_op(int cmd, unsigned long arg)
51 * @cmd == SCHEDOP_??? (scheduler operation).
52 * @arg == 0               (SCHEDOP_yield and SCHEDOP_block)
53 *      == SHUTDOWN_* code (SCHEDOP_shutdown)
54 *
55 * This legacy version is available to new guests as:
56 * ` long HYPERVISOR_sched_op_compat(enum sched_op cmd, unsigned long arg)
57 */
58
59/* ` enum sched_op { // SCHEDOP_* => struct sched_* */
60/*
61 * Voluntarily yield the CPU.
62 * @arg == NULL.
63 */
64#define SCHEDOP_yield       0
65
66/*
67 * Block execution of this VCPU until an event is received for processing.
68 * If called with event upcalls masked, this operation will atomically
69 * reenable event delivery and check for pending events before blocking the
70 * VCPU. This avoids a "wakeup waiting" race.
71 * @arg == NULL.
72 */
73#define SCHEDOP_block       1
74
75/*
76 * Halt execution of this domain (all VCPUs) and notify the system controller.
77 * @arg == pointer to sched_shutdown_t structure.
78 *
79 * If the sched_shutdown_t reason is SHUTDOWN_suspend then
80 * x86 PV guests must also set RDX (EDX for 32-bit guests) to the MFN
81 * of the guest's start info page.  RDX/EDX is the third hypercall
82 * argument.
83 *
84 * In addition, which reason is SHUTDOWN_suspend this hypercall
85 * returns 1 if suspend was cancelled or the domain was merely
86 * checkpointed, and 0 if it is resuming in a new domain.
87 */
88#define SCHEDOP_shutdown    2
89
90/*
91 * Poll a set of event-channel ports. Return when one or more are pending. An
92 * optional timeout may be specified.
93 * @arg == pointer to sched_poll_t structure.
94 */
95#define SCHEDOP_poll        3
96
97/*
98 * Declare a shutdown for another domain. The main use of this function is
99 * in interpreting shutdown requests and reasons for fully-virtualized
100 * domains.  A para-virtualized domain may use SCHEDOP_shutdown directly.
101 * @arg == pointer to sched_remote_shutdown_t structure.
102 */
103#define SCHEDOP_remote_shutdown        4
104
105/*
106 * Latch a shutdown code, so that when the domain later shuts down it
107 * reports this code to the control tools.
108 * @arg == sched_shutdown_t, as for SCHEDOP_shutdown.
109 */
110#define SCHEDOP_shutdown_code 5
111
112/*
113 * Setup, poke and destroy a domain watchdog timer.
114 * @arg == pointer to sched_watchdog_t structure.
115 * With id == 0, setup a domain watchdog timer to cause domain shutdown
116 *               after timeout, returns watchdog id.
117 * With id != 0 and timeout == 0, destroy domain watchdog timer.
118 * With id != 0 and timeout != 0, poke watchdog timer and set new timeout.
119 */
120#define SCHEDOP_watchdog    6
121
122/*
123 * Override the current vcpu affinity by pinning it to one physical cpu or
124 * undo this override restoring the previous affinity.
125 * @arg == pointer to sched_pin_override_t structure.
126 *
127 * A negative pcpu value will undo a previous pin override and restore the
128 * previous cpu affinity.
129 * This call is allowed for the hardware domain only and requires the cpu
130 * to be part of the domain's cpupool.
131 */
132#define SCHEDOP_pin_override 7
133/* ` } */
134
135struct sched_shutdown {
136    unsigned int reason; /* SHUTDOWN_* => enum sched_shutdown_reason */
137};
138typedef struct sched_shutdown sched_shutdown_t;
139DEFINE_XEN_GUEST_HANDLE(sched_shutdown_t);
140
141struct sched_poll {
142    XEN_GUEST_HANDLE(evtchn_port_t) ports;
143    unsigned int nr_ports;
144    uint64_t timeout;
145};
146typedef struct sched_poll sched_poll_t;
147DEFINE_XEN_GUEST_HANDLE(sched_poll_t);
148
149struct sched_remote_shutdown {
150    domid_t domain_id;         /* Remote domain ID */
151    unsigned int reason;       /* SHUTDOWN_* => enum sched_shutdown_reason */
152};
153typedef struct sched_remote_shutdown sched_remote_shutdown_t;
154DEFINE_XEN_GUEST_HANDLE(sched_remote_shutdown_t);
155
156struct sched_watchdog {
157    uint32_t id;                /* watchdog ID */
158    uint32_t timeout;           /* timeout */
159};
160typedef struct sched_watchdog sched_watchdog_t;
161DEFINE_XEN_GUEST_HANDLE(sched_watchdog_t);
162
163struct sched_pin_override {
164    int32_t pcpu;
165};
166typedef struct sched_pin_override sched_pin_override_t;
167DEFINE_XEN_GUEST_HANDLE(sched_pin_override_t);
168
169/*
170 * Reason codes for SCHEDOP_shutdown. These may be interpreted by control
171 * software to determine the appropriate action. For the most part, Xen does
172 * not care about the shutdown code.
173 */
174/* ` enum sched_shutdown_reason { */
175#define SHUTDOWN_poweroff   0  /* Domain exited normally. Clean up and kill. */
176#define SHUTDOWN_reboot     1  /* Clean up, kill, and then restart.          */
177#define SHUTDOWN_suspend    2  /* Clean up, save suspend info, kill.         */
178#define SHUTDOWN_crash      3  /* Tell controller we've crashed.             */
179#define SHUTDOWN_watchdog   4  /* Restart because watchdog time expired.     */
180
181/*
182 * Domain asked to perform 'soft reset' for it. The expected behavior is to
183 * reset internal Xen state for the domain returning it to the point where it
184 * was created but leaving the domain's memory contents and vCPU contexts
185 * intact. This will allow the domain to start over and set up all Xen specific
186 * interfaces again.
187 */
188#define SHUTDOWN_soft_reset 5
189#define SHUTDOWN_MAX        5  /* Maximum valid shutdown reason.             */
190/* ` } */
191
192#endif /* __XEN_PUBLIC_SCHED_H__ */
193
194/*
195 * Local variables:
196 * mode: C
197 * c-file-style: "BSD"
198 * c-basic-offset: 4
199 * tab-width: 4
200 * indent-tabs-mode: nil
201 * End:
202 */
203