4 * Implements the architecture independant portion of the LWKT
7 * $DragonFly: src/sys/sys/thread.h,v 1.6 2003/06/22 04:30:43 dillon Exp $
10 #ifndef _SYS_THREAD_H_
11 #define _SYS_THREAD_H_
25 typedef struct lwkt_queue *lwkt_queue_t;
26 typedef struct lwkt_token *lwkt_token_t;
27 typedef struct lwkt_wait *lwkt_wait_t;
28 typedef struct lwkt_msg *lwkt_msg_t;
29 typedef struct lwkt_port *lwkt_port_t;
30 typedef struct lwkt_cpu_msg *lwkt_cpu_msg_t;
31 typedef struct lwkt_cpu_port *lwkt_cpu_port_t;
32 typedef struct lwkt_rwlock *lwkt_rwlock_t;
33 typedef struct thread *thread_t;
35 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue;
36 typedef TAILQ_HEAD(lwkt_msg_queue, lwkt_msg) lwkt_msg_queue;
38 #include <machine/thread.h>
41 * Tokens arbitrate access to information. They are 'soft' arbitrators
42 * in that they are associated with cpus rather then threads, making the
43 * optimal aquisition case very fast if your cpu already happens to own the
44 * token you are requesting.
46 typedef struct lwkt_token {
47 int t_cpu; /* the current owner of the token */
48 int t_reqcpu; /* return ownership to this cpu on release */
50 int t_pri; /* raise thread priority to hold token */
55 * Wait structures deal with blocked threads. Due to the way remote cpus
56 * interact with these structures stable storage must be used.
58 typedef struct lwkt_wait {
59 lwkt_queue wa_waitq; /* list of waiting threads */
60 lwkt_token wa_token; /* who currently owns the list */
66 * The standarding message and port structure for communications between
69 typedef struct lwkt_msg {
70 TAILQ_ENTRY(lwkt_msg) ms_node;
71 lwkt_port_t ms_replyport;
77 #define MSGF_DONE 0x0001
78 #define MSGF_REPLY 0x0002
79 #define MSGF_QUEUED 0x0004
81 typedef struct lwkt_port {
82 lwkt_msg_queue mp_msgq;
86 #define mp_token mp_wait.wa_token
89 * The standard message and queue structure used for communications between
90 * cpus. Messages are typically queued via a machine-specific non-linked
91 * FIFO matrix allowing any cpu to send a message to any other cpu without
94 typedef struct lwkt_cpu_msg {
95 void (*cm_func)(lwkt_cpu_msg_t msg); /* primary dispatch function */
96 int cm_code; /* request code if applicable */
97 int cm_cpu; /* reply to cpu */
98 thread_t cm_originator; /* originating thread for wakeup */
104 typedef struct lwkt_rwlock {
110 #define rw_token rw_wait.wa_token
113 * Thread structure. Note that ownership of a thread structure is special
114 * cased and there is no 'token'. A thread is always owned by td_cpu and
115 * any manipulation of the thread by some other cpu must be done through
116 * cpu_*msg() functions. e.g. you could request ownership of a thread that
117 * way, or hand a thread off to another cpu by changing td_cpu and sending
118 * a schedule request to the other cpu.
121 TAILQ_ENTRY(thread) td_threadq;
122 struct proc *td_proc; /* (optional) associated process */
123 struct pcb *td_pcb; /* points to pcb and top of kstack */
124 const char *td_wmesg; /* string name for blockage */
125 int td_cpu; /* cpu owning the thread */
126 int td_pri; /* 0-31, 0=highest priority */
127 int td_flags; /* THF flags */
128 int td_gen; /* wait queue chasing generation number */
129 char *td_kstack; /* kernel stack */
130 char *td_sp; /* kernel stack pointer for LWKT restore */
131 void (*td_switch)(struct thread *ntd);
132 lwkt_wait_t td_wait; /* thread sitting on wait structure */
133 lwkt_rwlock td_rwlock; /* thread arbitration */
134 struct mi_thread td_mach;
137 #define td_token td_rwlock.rw_token
140 * Thread flags. Note that the RUNNING state is independant from the
141 * RUNQ/WAITQ state. That is, a thread's queueing state can be manipulated
142 * while it is running. If a thread is preempted it will always be moved
143 * back to the RUNQ if it isn't on it.
145 #define TDF_RUNNING 0x0001 /* currently running */
146 #define TDF_RUNQ 0x0002 /* on run queue */
149 * Thread priorities. Typically only one thread from any given
150 * user process scheduling queue is on the LWKT run queue at a time.
151 * Remember that there is one LWKT run queue per cpu.
153 * Critical sections are handled by bumping td_pri above TDPRI_MAX, which
154 * causes interrupts to be masked as they occur. When this occurs
155 * mycpu->gd_reqpri will be raised (possibly just set to TDPRI_CRIT for
156 * interrupt masking).
158 #define TDPRI_IDLE_THREAD 0 /* the idle thread */
159 #define TDPRI_USER_IDLE 4 /* user scheduler idle */
160 #define TDPRI_USER_NORM 6 /* user scheduler normal */
161 #define TDPRI_USER_REAL 8 /* user scheduler real time */
162 #define TDPRI_KERN_USER 10 /* kernel / block in syscall */
163 #define TDPRI_SOFT_NORM 14 /* kernel / normal */
164 #define TDPRI_SOFT_TIMER 16 /* kernel / timer */
165 #define TDPRI_EXITING 19 /* exiting thread */
166 #define TDPRI_INT_SUPPORT 20 /* kernel / high priority support */
167 #define TDPRI_INT_LOW 27 /* low priority interrupt */
168 #define TDPRI_INT_MED 28 /* medium priority interrupt */
169 #define TDPRI_INT_HIGH 29 /* high priority interrupt */
172 #define TDPRI_MASK 31
173 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */
175 #define CACHE_NTHREADS 4
179 extern struct vm_zone *thread_zone;
181 extern struct thread *lwkt_alloc_thread(void);
182 extern void lwkt_init_thread(struct thread *td, void *stack);
183 extern void lwkt_init_wait(struct lwkt_wait *w);
184 extern void lwkt_gdinit(struct globaldata *gd);
185 extern void lwkt_switch(void);
186 extern void lwkt_preempt(void);
187 extern void lwkt_schedule(thread_t td);
188 extern void lwkt_schedule_self(void);
189 extern void lwkt_deschedule(thread_t td);
190 extern void lwkt_deschedule_self(void);
191 extern void lwkt_yield(void);
192 extern void lwkt_yield_quick(void);
194 extern void lwkt_block(lwkt_wait_t w, const char *wmesg, int *gen);
195 extern void lwkt_signal(lwkt_wait_t w);
196 extern void lwkt_gettoken(lwkt_token_t tok);
197 extern void lwkt_reltoken(lwkt_token_t tok);
198 extern int lwkt_regettoken(lwkt_token_t tok);
199 extern void lwkt_rwlock_init(lwkt_rwlock_t lock);
200 extern void lwkt_exlock(lwkt_rwlock_t lock, const char *wmesg);
201 extern void lwkt_shlock(lwkt_rwlock_t lock, const char *wmesg);
202 extern void lwkt_exunlock(lwkt_rwlock_t lock);
203 extern void lwkt_shunlock(lwkt_rwlock_t lock);