4 * Implements inline procedure support for the LWKT subsystem.
6 * Generally speaking these routines only operate on threads associated
7 * with the current cpu. For example, a higher priority thread pending
8 * on a different cpu will not be immediately scheduled by a yield() on
12 #ifndef _SYS_THREAD2_H_
13 #define _SYS_THREAD2_H_
17 #error "This file should not be included by userland programs."
22 * Userland will have its own globaldata which it includes prior to this.
25 #include <sys/systm.h>
27 #ifndef _SYS_GLOBALDATA_H_
28 #include <sys/globaldata.h>
30 #include <machine/cpufunc.h>
33 * Is a token held by the specified thread?
36 _lwkt_token_held(lwkt_token_t tok, thread_t td)
38 return (tok->t_ref >= &td->td_toks_base &&
39 tok->t_ref < td->td_toks_stop);
43 * Critical section debugging
45 #ifdef DEBUG_CRIT_SECTIONS
46 #define __DEBUG_CRIT_ARG__ const char *id
47 #define __DEBUG_CRIT_ADD_ARG__ , const char *id
48 #define __DEBUG_CRIT_PASS_ARG__ , id
49 #define __DEBUG_CRIT_ENTER(td) _debug_crit_enter((td), id)
50 #define __DEBUG_CRIT_EXIT(td) _debug_crit_exit((td), id)
51 #define crit_enter() _crit_enter(mycpu, __FUNCTION__)
52 #define crit_enter_id(id) _crit_enter(mycpu, id)
53 #define crit_enter_gd(curgd) _crit_enter((curgd), __FUNCTION__)
54 #define crit_enter_quick(curtd) _crit_enter_quick((curtd), __FUNCTION__)
55 #define crit_enter_hard() _crit_enter_hard(mycpu, __FUNCTION__)
56 #define crit_enter_hard_gd(curgd) _crit_enter_hard((curgd), __FUNCTION__)
57 #define crit_exit() _crit_exit(mycpu, __FUNCTION__)
58 #define crit_exit_id(id) _crit_exit(mycpu, id)
59 #define crit_exit_gd(curgd) _crit_exit((curgd), __FUNCTION__)
60 #define crit_exit_quick(curtd) _crit_exit_quick((curtd), __FUNCTION__)
61 #define crit_exit_hard() _crit_exit_hard(mycpu, __FUNCTION__)
62 #define crit_exit_hard_gd(curgd) _crit_exit_hard((curgd), __FUNCTION__)
63 #define crit_exit_noyield(curtd) _crit_exit_noyield((curtd),__FUNCTION__)
65 #define __DEBUG_CRIT_ARG__ void
66 #define __DEBUG_CRIT_ADD_ARG__
67 #define __DEBUG_CRIT_PASS_ARG__
68 #define __DEBUG_CRIT_ENTER(td)
69 #define __DEBUG_CRIT_EXIT(td)
70 #define crit_enter() _crit_enter(mycpu)
71 #define crit_enter_id(id) _crit_enter(mycpu)
72 #define crit_enter_gd(curgd) _crit_enter((curgd))
73 #define crit_enter_quick(curtd) _crit_enter_quick((curtd))
74 #define crit_enter_hard() _crit_enter_hard(mycpu)
75 #define crit_enter_hard_gd(curgd) _crit_enter_hard((curgd))
76 #define crit_exit() crit_exit_wrapper()
77 #define crit_exit_id(id) _crit_exit(mycpu)
78 #define crit_exit_gd(curgd) _crit_exit((curgd))
79 #define crit_exit_quick(curtd) _crit_exit_quick((curtd))
80 #define crit_exit_hard() _crit_exit_hard(mycpu)
81 #define crit_exit_hard_gd(curgd) _crit_exit_hard((curgd))
82 #define crit_exit_noyield(curtd) _crit_exit_noyield((curtd))
85 extern void crit_exit_wrapper(__DEBUG_CRIT_ARG__);
88 * Track crit_enter()/crit_exit() pairs and warn on mismatches.
90 #ifdef DEBUG_CRIT_SECTIONS
93 _debug_crit_enter(thread_t td, const char *id)
95 int wi = td->td_crit_debug_index;
97 td->td_crit_debug_array[wi & CRIT_DEBUG_ARRAY_MASK] = id;
98 ++td->td_crit_debug_index;
102 _debug_crit_exit(thread_t td, const char *id)
107 wi = td->td_crit_debug_index - 1;
108 if ((gid = td->td_crit_debug_array[wi & CRIT_DEBUG_ARRAY_MASK]) != id) {
109 if (td->td_in_crit_report == 0) {
110 td->td_in_crit_report = 1;
111 kprintf("crit_exit(%s) expected id %s\n", id, gid);
112 td->td_in_crit_report = 0;
115 --td->td_crit_debug_index;
121 * Critical sections prevent preemption, but allowing explicit blocking
122 * and thread switching. Any interrupt occuring while in a critical
123 * section is made pending and returns immediately. Interrupts are not
124 * physically disabled.
126 * Hard critical sections prevent preemption and disallow any blocking
127 * or thread switching, and in addition will assert on any blockable
128 * operation (acquire token not already held, lockmgr, mutex ops, or
129 * splz). Spinlocks can still be used in hard sections.
131 * All critical section routines only operate on the current thread.
132 * Passed gd or td arguments are simply optimizations when mycpu or
133 * curthread is already available to the caller.
140 _crit_enter_quick(thread_t td __DEBUG_CRIT_ADD_ARG__)
143 __DEBUG_CRIT_ENTER(td);
148 _crit_enter(globaldata_t gd __DEBUG_CRIT_ADD_ARG__)
150 _crit_enter_quick(gd->gd_curthread __DEBUG_CRIT_PASS_ARG__);
154 _crit_enter_hard(globaldata_t gd __DEBUG_CRIT_ADD_ARG__)
156 _crit_enter_quick(gd->gd_curthread __DEBUG_CRIT_PASS_ARG__);
157 ++gd->gd_intr_nesting_level;
164 * NOTE: Conditionalizing just gd_reqflags, a case which is virtually
165 * never true regardless of crit_count, should result in 100%
166 * optimal code execution. We don't check crit_count because
167 * it just bloats the inline and does not improve performance.
169 * NOTE: This can produce a considerable amount of code despite the
170 * relatively few lines of code so the non-debug case typically
171 * just wraps it in a real function, crit_exit_wrapper().
174 _crit_exit_noyield(thread_t td __DEBUG_CRIT_ADD_ARG__)
176 __DEBUG_CRIT_EXIT(td);
179 if (__predict_false(td->td_critcount < 0))
182 cpu_ccfence(); /* prevent compiler reordering */
186 _crit_exit_quick(thread_t td __DEBUG_CRIT_ADD_ARG__)
188 _crit_exit_noyield(td __DEBUG_CRIT_PASS_ARG__);
189 if (__predict_false(td->td_gd->gd_reqflags & RQF_IDLECHECK_MASK))
194 _crit_exit(globaldata_t gd __DEBUG_CRIT_ADD_ARG__)
196 _crit_exit_quick(gd->gd_curthread __DEBUG_CRIT_PASS_ARG__);
200 _crit_exit_hard(globaldata_t gd __DEBUG_CRIT_ADD_ARG__)
202 --gd->gd_intr_nesting_level;
203 _crit_exit_quick(gd->gd_curthread __DEBUG_CRIT_PASS_ARG__);
207 crit_test(thread_t td)
209 return(td->td_critcount);
213 * Return whether any threads are runnable.
218 return (TAILQ_FIRST(&mycpu->gd_tdrunq) != NULL);
222 lwkt_getpri(thread_t td)
228 lwkt_getpri_self(void)
230 return(lwkt_getpri(curthread));
234 * Reduce our priority in preparation for a return to userland. If
235 * our passive release function was still in place, our priority was
236 * never raised and does not need to be reduced.
238 * See also lwkt_passive_release() and platform/blah/trap.c
241 lwkt_passive_recover(thread_t td)
243 if (td->td_release == NULL)
244 lwkt_setpri_self(TDPRI_USER_NORM);
245 td->td_release = NULL;
252 lwkt_cpusync_init(lwkt_cpusync_t cs, cpumask_t mask,
253 cpusync_func_t func, void *data)
256 /* cs->cs_mack = 0; handled by _interlock */
264 * IPIQ messaging wrappers. IPIQ remote functions are passed three arguments:
265 * a void * pointer, an integer, and a pointer to the trap frame (or NULL if
266 * the trap frame is not known). However, we wish to provide opaque
267 * interfaces for simpler callbacks... the basic IPI messaging function as
268 * used by the kernel takes a single argument.
271 lwkt_send_ipiq(globaldata_t target, ipifunc1_t func, void *arg)
273 return(lwkt_send_ipiq3(target, (ipifunc3_t)func, arg, 0));
277 lwkt_send_ipiq2(globaldata_t target, ipifunc2_t func, void *arg1, int arg2)
279 return(lwkt_send_ipiq3(target, (ipifunc3_t)func, arg1, arg2));
283 lwkt_send_ipiq_mask(cpumask_t mask, ipifunc1_t func, void *arg)
285 return(lwkt_send_ipiq3_mask(mask, (ipifunc3_t)func, arg, 0));
289 lwkt_send_ipiq2_mask(cpumask_t mask, ipifunc2_t func, void *arg1, int arg2)
291 return(lwkt_send_ipiq3_mask(mask, (ipifunc3_t)func, arg1, arg2));
295 lwkt_send_ipiq_nowait(globaldata_t target, ipifunc1_t func, void *arg)
297 return(lwkt_send_ipiq3_nowait(target, (ipifunc3_t)func, arg, 0));
301 lwkt_send_ipiq2_nowait(globaldata_t target, ipifunc2_t func,
302 void *arg1, int arg2)
304 return(lwkt_send_ipiq3_nowait(target, (ipifunc3_t)func, arg1, arg2));
308 lwkt_send_ipiq_passive(globaldata_t target, ipifunc1_t func, void *arg)
310 return(lwkt_send_ipiq3_passive(target, (ipifunc3_t)func, arg, 0));
314 lwkt_send_ipiq2_passive(globaldata_t target, ipifunc2_t func,
315 void *arg1, int arg2)
317 return(lwkt_send_ipiq3_passive(target, (ipifunc3_t)func, arg1, arg2));
321 lwkt_send_ipiq_bycpu(int dcpu, ipifunc1_t func, void *arg)
323 return(lwkt_send_ipiq3_bycpu(dcpu, (ipifunc3_t)func, arg, 0));
327 lwkt_send_ipiq2_bycpu(int dcpu, ipifunc2_t func, void *arg1, int arg2)
329 return(lwkt_send_ipiq3_bycpu(dcpu, (ipifunc3_t)func, arg1, arg2));
334 #endif /* _SYS_THREAD2_H_ */