4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
29 #include <sys/kcondvar.h>
36 * definitions of callback classes (c_class)
38 * Callbacks belong in the same class if (1) their callback routines
39 * do the same kind of processing (ideally, using the same callback function)
40 * and (2) they can/should be executed at the same time in a cpr
41 * suspend/resume operation.
43 * Note: The DAEMON class, in particular, is for stopping kernel threads
44 * and nothing else. The CALLB_* macros below should be used to deal
45 * with kernel threads, and the callback function should be callb_generic_cpr.
46 * Another idiosyncrasy of the DAEMON class is that if a suspend operation
47 * fails, some of the callback functions may be called with the RESUME
48 * code which were never called with SUSPEND. Not a problem currently,
49 * but see bug 4201851.
51 #define CB_CL_CPR_DAEMON 0
52 #define CB_CL_CPR_VM 1
53 #define CB_CL_CPR_CALLOUT 2
54 #define CB_CL_CPR_OBP 3
55 #define CB_CL_CPR_FB 4
57 #define CB_CL_CPR_RPC 6
58 #define CB_CL_CPR_PROMPRINTF 7
59 #define CB_CL_UADMIN 8
60 #define CB_CL_CPR_PM 9
62 #define CB_CL_CPR_DMA 11
63 #define CB_CL_CPR_POST_USER 12
64 #define CB_CL_UADMIN_PRE_VFS 13
65 #define CB_CL_MDBOOT CB_CL_UADMIN
66 #define CB_CL_ENTER_DEBUGGER 14
67 #define CB_CL_CPR_POST_KERNEL 15
68 #define CB_CL_CPU_DEEP_IDLE 16
69 #define NCBCLASS 17 /* CHANGE ME if classes are added/removed */
72 * CB_CL_CPR_DAEMON class specific definitions are given below:
76 * code for CPR callb_execute_class
78 #define CB_CODE_CPR_CHKPT 0
79 #define CB_CODE_CPR_RESUME 1
81 typedef void * callb_id_t;
83 * Per kernel thread structure for CPR daemon callbacks.
84 * Must be protected by either a existing lock in the daemon or
85 * a new lock created for such a purpose.
87 typedef struct callb_cpr {
88 kmutex_t *cc_lockp; /* lock to protect this struct */
89 char cc_events; /* various events for CPR */
90 callb_id_t cc_id; /* callb id address */
91 kcondvar_t cc_callb_cv; /* cv for callback waiting */
92 kcondvar_t cc_stop_cv; /* cv to checkpoint block */
96 * cc_events definitions
98 #define CALLB_CPR_START 1 /* a checkpoint request's started */
99 #define CALLB_CPR_SAFE 2 /* thread is safe for CPR */
100 #define CALLB_CPR_ALWAYS_SAFE 4 /* thread is ALWAYS safe for CPR */
103 * Used when checking that all kernel threads are stopped.
105 #define CALLB_MAX_RETRY 3 /* when waiting for kthread to sleep */
106 #define CALLB_THREAD_DELAY 10 /* ticks allowed to reach sleep */
107 #define CPR_KTHREAD_TIMEOUT_SEC 90 /* secs before callback times out -- */
108 /* due to pwr mgmt of disks, make -- */
109 /* big enough for worst spinup time */
114 * CALLB_CPR_INIT macro is used by kernel threads to add their entry to
115 * the callback table and perform other initialization. It automatically
116 * adds the thread as being in the callback class CB_CL_CPR_DAEMON.
118 * cp - ptr to the callb_cpr_t structure for this kernel thread
120 * lockp - pointer to mutex protecting the callb_cpr_t stuct
122 * func - pointer to the callback function for this kernel thread.
123 * It has the prototype boolean_t <func>(void *arg, int code)
124 * where: arg - ptr to the callb_cpr_t structure
125 * code - not used for this type of callback
126 * returns: B_TRUE if successful; B_FALSE if unsuccessful.
128 * name - a string giving the name of the kernel thread
130 * Note: lockp is the lock to protect the callb_cpr_t (cp) structure
131 * later on. No lock held is needed for this initialization.
133 #define CALLB_CPR_INIT(cp, lockp, func, name) { \
134 strlcpy(curthread->td_name, (name), \
135 sizeof(curthread->td_name)); \
136 bzero((caddr_t)(cp), sizeof (callb_cpr_t)); \
137 (cp)->cc_lockp = lockp; \
138 (cp)->cc_id = callb_add(func, (void *)(cp), \
139 CB_CL_CPR_DAEMON, name); \
140 cv_init(&(cp)->cc_callb_cv, NULL, CV_DEFAULT, NULL); \
141 cv_init(&(cp)->cc_stop_cv, NULL, CV_DEFAULT, NULL); \
145 #define CALLB_CPR_ASSERT(cp) ASSERT(MUTEX_HELD((cp)->cc_lockp));
147 #define CALLB_CPR_ASSERT(cp)
150 * Some threads (like the idle threads) do not adhere to the callback
151 * protocol and are always considered safe. Such threads must never exit.
152 * They register their presence by calling this macro during their
156 * t - thread pointer of the client kernel thread
157 * name - a string giving the name of the kernel thread
159 #define CALLB_CPR_INIT_SAFE(t, name) { \
160 (void) callb_add_thread(callb_generic_cpr_safe, \
161 (void *) &callb_cprinfo_safe, CB_CL_CPR_DAEMON, \
165 * The lock to protect cp's content must be held before
166 * calling the following two macros.
168 * Any code region between CALLB_CPR_SAFE_BEGIN and CALLB_CPR_SAFE_END
169 * is safe for checkpoint/resume.
171 #define CALLB_CPR_SAFE_BEGIN(cp) { \
172 CALLB_CPR_ASSERT(cp) \
173 (cp)->cc_events |= CALLB_CPR_SAFE; \
174 if ((cp)->cc_events & CALLB_CPR_START) \
175 cv_signal(&(cp)->cc_callb_cv); \
177 #define CALLB_CPR_SAFE_END(cp, lockp) { \
178 CALLB_CPR_ASSERT(cp) \
179 while ((cp)->cc_events & CALLB_CPR_START) \
180 cv_wait(&(cp)->cc_stop_cv, lockp); \
181 (cp)->cc_events &= ~CALLB_CPR_SAFE; \
184 * cv_destroy is nop right now but may be needed in the future.
186 #define CALLB_CPR_EXIT(cp) { \
187 CALLB_CPR_ASSERT(cp) \
188 (cp)->cc_events |= CALLB_CPR_SAFE; \
189 if ((cp)->cc_events & CALLB_CPR_START) \
190 cv_signal(&(cp)->cc_callb_cv); \
191 mutex_exit((cp)->cc_lockp); \
192 (void) callb_delete((cp)->cc_id); \
193 cv_destroy(&(cp)->cc_callb_cv); \
194 cv_destroy(&(cp)->cc_stop_cv); \
197 extern callb_cpr_t callb_cprinfo_safe;
198 extern callb_id_t callb_add(boolean_t (*)(void *, int), void *, int, char *);
199 extern callb_id_t callb_add_thread(boolean_t (*)(void *, int),
200 void *, int, char *, kthread_id_t);
201 extern int callb_delete(callb_id_t);
202 extern void callb_execute(callb_id_t, int);
203 extern void *callb_execute_class(int, int);
204 extern boolean_t callb_generic_cpr(void *, int);
205 extern boolean_t callb_generic_cpr_safe(void *, int);
206 extern boolean_t callb_is_stopped(kthread_id_t, caddr_t *);
207 extern void callb_lock_table(void);
208 extern void callb_unlock_table(void);
215 #endif /* _SYS_CALLB_H */