4 * Implements the architecture independant portion of the LWKT
7 * Types which must already be defined when this header is included by
8 * userland: struct md_thread
10 * $DragonFly: src/sys/sys/thread.h,v 1.38 2003/12/07 04:20:38 dillon Exp $
13 #ifndef _SYS_THREAD_H_
14 #define _SYS_THREAD_H_
16 #ifndef _SYS_STDINT_H_
17 #include <sys/stdint.h> /* __int types */
20 #include <sys/param.h> /* MAXCOMLEN */
23 #include <sys/queue.h> /* TAILQ_* macros */
25 #ifndef _SYS_MSGPORT_H_
26 #include <sys/msgport.h> /* lwkt_port */
43 typedef struct lwkt_queue *lwkt_queue_t;
44 typedef struct lwkt_token *lwkt_token_t;
45 typedef struct lwkt_wait *lwkt_wait_t;
46 typedef struct lwkt_cpu_msg *lwkt_cpu_msg_t;
47 typedef struct lwkt_cpu_port *lwkt_cpu_port_t;
48 typedef struct lwkt_rwlock *lwkt_rwlock_t;
49 typedef struct lwkt_ipiq *lwkt_ipiq_t;
50 typedef struct thread *thread_t;
52 typedef TAILQ_HEAD(lwkt_queue, thread) lwkt_queue;
55 * Differentiation between kernel threads and user threads. Userland
56 * programs which want to access to kernel structures have to define
57 * _KERNEL_STRUCTURES. This is a kinda safety valve to prevent badly
58 * written user programs from getting an LWKT thread that is neither the
59 * kernel nor the user version.
61 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
62 #ifndef _MACHINE_THREAD_H_
63 #include <machine/thread.h> /* md_thread */
68 * Tokens arbitrate access to information. They are 'soft' arbitrators
69 * in that they are associated with cpus rather then threads, making the
70 * optimal aquisition case very fast if your cpu already happens to own the
71 * token you are requesting.
73 typedef struct lwkt_token {
74 int t_cpu; /* the current owner of the token */
75 int t_reqcpu; /* return ownership to this cpu on release */
76 int t_gen; /* generation number */
80 * Wait structures deal with blocked threads. Due to the way remote cpus
81 * interact with these structures stable storage must be used.
83 typedef struct lwkt_wait {
84 lwkt_queue wa_waitq; /* list of waiting threads */
85 lwkt_token wa_token; /* who currently owns the list */
90 #define MAXCPUFIFO 16 /* power of 2 */
91 #define MAXCPUFIFO_MASK (MAXCPUFIFO - 1)
93 typedef void (*ipifunc_t)(void *arg);
95 typedef struct lwkt_ipiq {
96 int ip_rindex; /* only written by target cpu */
97 int ip_xindex; /* writte by target, indicates completion */
98 int ip_windex; /* only written by source cpu */
99 ipifunc_t ip_func[MAXCPUFIFO];
100 void *ip_arg[MAXCPUFIFO];
104 * The standard message and queue structure used for communications between
105 * cpus. Messages are typically queued via a machine-specific non-linked
106 * FIFO matrix allowing any cpu to send a message to any other cpu without
109 typedef struct lwkt_cpu_msg {
110 void (*cm_func)(lwkt_cpu_msg_t msg); /* primary dispatch function */
111 int cm_code; /* request code if applicable */
112 int cm_cpu; /* reply to cpu */
113 thread_t cm_originator; /* originating thread for wakeup */
119 typedef struct lwkt_rwlock {
126 #define rw_token rw_wait.wa_token
129 * Thread structure. Note that ownership of a thread structure is special
130 * cased and there is no 'token'. A thread is always owned by the cpu
131 * represented by td_gd, any manipulation of the thread by some other cpu
132 * must be done through cpu_*msg() functions. e.g. you could request
133 * ownership of a thread that way, or hand a thread off to another cpu.
135 * NOTE: td_pri is bumped by TDPRI_CRIT when entering a critical section,
136 * but this does not effect how the thread is scheduled by LWKT.
141 TAILQ_ENTRY(thread) td_threadq;
142 TAILQ_ENTRY(thread) td_allq;
143 lwkt_port td_msgport; /* built-in message port for replies */
144 struct proc *td_proc; /* (optional) associated process */
145 struct pcb *td_pcb; /* points to pcb and top of kstack */
146 struct globaldata *td_gd; /* associated with this cpu */
147 const char *td_wmesg; /* string name for blockage */
148 void *td_wchan; /* waiting on channel */
149 int td_pri; /* 0-31, 31=highest priority (note 1) */
150 int td_flags; /* TDF flags */
151 int td_gen; /* wait queue chasing generation number */
153 void (*td_preemptable)(struct thread *td, int critpri);
154 void (*td_release)(struct thread *td);
156 struct md_intr_info *intdata;
158 char *td_kstack; /* kernel stack */
159 char *td_sp; /* kernel stack pointer for LWKT restore */
160 void (*td_switch)(struct thread *ntd);
161 lwkt_wait_t td_wait; /* thread sitting on wait structure */
162 __uint64_t td_uticks; /* Statclock hits in user mode (uS) */
163 __uint64_t td_sticks; /* Statclock hits in system mode (uS) */
164 __uint64_t td_iticks; /* Statclock hits processing intr (uS) */
165 int td_locks; /* lockmgr lock debugging YYY */
166 int td_refs; /* hold position in gd_tdallq / hold free */
167 int td_nest_count; /* prevent splz nesting */
169 int td_mpcount; /* MP lock held (count) */
173 char td_comm[MAXCOMLEN+1]; /* typ 16+1 bytes */
174 struct thread *td_preempted; /* we preempted this thread */
175 struct md_thread td_mach;
179 * Thread flags. Note that TDF_RUNNING is cleared on the old thread after
180 * we switch to the new one, which is necessary because LWKTs don't need
181 * to hold the BGL. This flag is used by the exit code and the managed
182 * thread migration code.
184 * LWKT threads stay on their (per-cpu) run queue while running, not to
185 * be confused with user processes which are removed from the user scheduling
186 * run queue while actually running.
188 #define TDF_RUNNING 0x0001 /* thread still active */
189 #define TDF_RUNQ 0x0002 /* on an LWKT run queue */
190 #define TDF_PREEMPT_LOCK 0x0004 /* I have been preempted */
191 #define TDF_PREEMPT_DONE 0x0008 /* acknowledge preemption complete */
192 #define TDF_IDLE_NOHLT 0x0010 /* we need to spin */
194 #define TDF_SYSTHREAD 0x0100 /* system thread */
195 #define TDF_ALLOCATED_THREAD 0x0200 /* zalloc allocated thread */
196 #define TDF_ALLOCATED_STACK 0x0400 /* zalloc allocated stack */
197 #define TDF_VERBOSE 0x0800 /* verbose on exit */
198 #define TDF_DEADLKTREAT 0x1000 /* special lockmgr deadlock treatment */
199 #define TDF_STOPREQ 0x2000 /* suspend_kproc */
200 #define TDF_WAKEREQ 0x4000 /* resume_kproc */
201 #define TDF_TIMEOUT 0x8000 /* tsleep timeout */
202 #define TDF_INTTHREAD 0x00010000 /* interrupt thread */
205 * Thread priorities. Typically only one thread from any given
206 * user process scheduling queue is on the LWKT run queue at a time.
207 * Remember that there is one LWKT run queue per cpu.
209 * Critical sections are handled by bumping td_pri above TDPRI_MAX, which
210 * causes interrupts to be masked as they occur. When this occurs a
211 * rollup flag will be set in mycpu->gd_reqflags.
213 #define TDPRI_IDLE_THREAD 0 /* the idle thread */
214 #define TDPRI_USER_IDLE 4 /* user scheduler idle */
215 #define TDPRI_USER_NORM 6 /* user scheduler normal */
216 #define TDPRI_USER_REAL 8 /* user scheduler real time */
217 #define TDPRI_KERN_LPSCHED 9 /* scheduler helper for userland sch */
218 #define TDPRI_KERN_USER 10 /* kernel / block in syscall */
219 #define TDPRI_KERN_DAEMON 12 /* kernel daemon (pageout, etc) */
220 #define TDPRI_SOFT_NORM 14 /* kernel / normal */
221 #define TDPRI_SOFT_TIMER 16 /* kernel / timer */
222 #define TDPRI_EXITING 19 /* exiting thread */
223 #define TDPRI_INT_SUPPORT 20 /* kernel / high priority support */
224 #define TDPRI_INT_LOW 27 /* low priority interrupt */
225 #define TDPRI_INT_MED 28 /* medium priority interrupt */
226 #define TDPRI_INT_HIGH 29 /* high priority interrupt */
229 #define TDPRI_MASK 31
230 #define TDPRI_CRIT 32 /* high bits of td_pri used for crit */
232 #define CACHE_NTHREADS 6
234 #define IN_CRITICAL_SECT(td) ((td)->td_pri >= TDPRI_CRIT)
238 extern struct vm_zone *thread_zone;
243 * Applies both to the kernel and to liblwkt.
245 extern struct thread *lwkt_alloc_thread(struct thread *template, int cpu);
246 extern void lwkt_init_thread(struct thread *td, void *stack, int flags,
247 struct globaldata *gd);
248 extern void lwkt_set_comm(thread_t td, const char *ctl, ...);
249 extern void lwkt_wait_free(struct thread *td);
250 extern void lwkt_free_thread(struct thread *td);
251 extern void lwkt_init_wait(struct lwkt_wait *w);
252 extern void lwkt_gdinit(struct globaldata *gd);
253 extern void lwkt_switch(void);
254 extern void lwkt_maybe_switch(void);
255 extern void lwkt_preempt(thread_t ntd, int critpri);
256 extern void lwkt_schedule(thread_t td);
257 extern void lwkt_schedule_self(void);
258 extern void lwkt_deschedule(thread_t td);
259 extern void lwkt_deschedule_self(void);
260 extern void lwkt_acquire(thread_t td);
261 extern void lwkt_yield(void);
262 extern void lwkt_yield_quick(void);
263 extern void lwkt_hold(thread_t td);
264 extern void lwkt_rele(thread_t td);
266 extern void lwkt_block(lwkt_wait_t w, const char *wmesg, int *gen);
267 extern void lwkt_signal(lwkt_wait_t w, int count);
268 extern int lwkt_trytoken(lwkt_token_t tok);
269 extern int lwkt_gettoken(lwkt_token_t tok);
270 extern int lwkt_gentoken(lwkt_token_t tok, int *gen);
271 extern int lwkt_reltoken(lwkt_token_t tok);
272 extern void lwkt_inittoken(lwkt_token_t tok);
273 extern int lwkt_regettoken(lwkt_token_t tok);
274 extern void lwkt_rwlock_init(lwkt_rwlock_t lock);
275 extern void lwkt_exlock(lwkt_rwlock_t lock, const char *wmesg);
276 extern void lwkt_shlock(lwkt_rwlock_t lock, const char *wmesg);
277 extern void lwkt_exunlock(lwkt_rwlock_t lock);
278 extern void lwkt_shunlock(lwkt_rwlock_t lock);
279 extern void lwkt_setpri(thread_t td, int pri);
280 extern void lwkt_setpri_self(int pri);
281 extern int lwkt_send_ipiq(int dcpu, ipifunc_t func, void *arg);
282 extern void lwkt_send_ipiq_mask(u_int32_t mask, ipifunc_t func, void *arg);
283 extern void lwkt_wait_ipiq(int dcpu, int seq);
284 extern void lwkt_process_ipiq(void);
285 extern void crit_panic(void);
286 extern struct proc *lwkt_preempted_proc(void);
288 extern int lwkt_create (void (*func)(void *), void *arg, struct thread **ptd,
289 struct thread *template, int tdflags, int cpu,
290 const char *ctl, ...);
291 extern void lwkt_exit (void) __dead2;