1 /* $NetBSD: lwp.h,v 1.215 2022/04/09 23:45:37 riastradh Exp $ */ 2 3 /* 4 * Copyright (c) 2001, 2006, 2007, 2008, 2009, 2010, 2019, 2020 5 * The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Nathan J. Williams and Andrew Doran. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #ifndef _SYS_LWP_H_ 34 #define _SYS_LWP_H_ 35 36 #if defined(_KERNEL) || defined(_KMEMUSER) 37 38 #include <sys/param.h> 39 #include <sys/time.h> 40 #include <sys/queue.h> 41 #include <sys/callout.h> 42 #include <sys/kcpuset.h> 43 #include <sys/mutex.h> 44 #include <sys/condvar.h> 45 #include <sys/signalvar.h> 46 #include <sys/sched.h> 47 #include <sys/specificdata.h> 48 #include <sys/syncobj.h> 49 #include <sys/resource.h> 50 51 #if defined(_KERNEL) 52 struct lwp; 53 /* forward declare this for <machine/cpu.h> so it can get l_cpu. */ 54 static __inline struct cpu_info *lwp_getcpu(struct lwp *); 55 #include <machine/cpu.h> /* curcpu() and cpu_info */ 56 #include <sys/atomic.h> 57 #ifdef _KERNEL_OPT 58 #include "opt_kcov.h" 59 #include "opt_kmsan.h" 60 #endif 61 #endif 62 63 #include <machine/proc.h> /* Machine-dependent proc substruct. */ 64 65 /* 66 * Lightweight process. Field markings and the corresponding locks: 67 * 68 * a: proc_lock 69 * c: condition variable interlock, passed to cv_wait() 70 * l: *l_mutex 71 * p: l_proc->p_lock 72 * s: spc_mutex, which may or may not be referenced by l_mutex 73 * S: l_selcluster->sc_lock 74 * (: unlocked, stable 75 * !: unlocked, may only be reliably accessed by the LWP itself 76 * 77 * Fields are clustered together by usage (to increase the likelihood 78 * of cache hits) and by size (to reduce dead space in the structure). 79 */ 80 81 #include <sys/pcu.h> 82 83 struct lockdebug; 84 struct sysent; 85 86 struct lwp { 87 /* Must not be zeroed on free. */ 88 struct cpu_info *volatile l_cpu;/* s: CPU we're on if LSONPROC */ 89 kmutex_t * volatile l_mutex; /* l: ptr to mutex on sched state */ 90 struct turnstile *l_ts; /* l: current turnstile */ 91 int l_stat; /* l: overall LWP status */ 92 int l__reserved; /* : padding - reuse as needed */ 93 94 /* Scheduling and overall state. */ 95 #define l_startzero l_runq 96 TAILQ_ENTRY(lwp) l_runq; /* s: run queue */ 97 union { 98 void * info; /* s: scheduler-specific structure */ 99 u_int timeslice; /* l: time-quantum for SCHED_M2 */ 100 } l_sched; 101 void *l_addr; /* l: PCB address; use lwp_getpcb() */ 102 struct mdlwp l_md; /* l: machine-dependent fields. */ 103 struct bintime l_rtime; /* l: real time */ 104 struct bintime l_stime; /* l: start time (while ONPROC) */ 105 int l_flag; /* l: misc flag values */ 106 u_int l_swtime; /* l: time swapped in or out */ 107 u_int l_rticks; /* l: Saved start time of run */ 108 u_int l_rticksum; /* l: Sum of ticks spent running */ 109 u_int l_slpticks; /* l: Saved start time of sleep */ 110 u_int l_slpticksum; /* l: Sum of ticks spent sleeping */ 111 int l_biglocks; /* l: biglock count before sleep */ 112 int l_class; /* l: scheduling class */ 113 int l_kpriority; /* !: has kernel priority boost */ 114 pri_t l_kpribase; /* !: kernel priority base level */ 115 pri_t l_priority; /* l: scheduler priority */ 116 pri_t l_inheritedprio;/* l: inherited priority */ 117 pri_t l_protectprio; /* l: for PTHREAD_PRIO_PROTECT */ 118 pri_t l_auxprio; /* l: max(inherit,protect) priority */ 119 int l_protectdepth; /* l: for PTHREAD_PRIO_PROTECT */ 120 u_int l_cpticks; /* (: Ticks of CPU time */ 121 psetid_t l_psid; /* l: assigned processor-set ID */ 122 fixpt_t l_pctcpu; /* p: %cpu during l_swtime */ 123 fixpt_t l_estcpu; /* l: cpu time for SCHED_4BSD */ 124 volatile uint64_t l_ncsw; /* l: total context switches */ 125 volatile uint64_t l_nivcsw; /* l: involuntary context switches */ 126 SLIST_HEAD(, turnstile) l_pi_lenders; /* l: ts lending us priority */ 127 struct cpu_info *l_target_cpu; /* l: target CPU to migrate */ 128 struct lwpctl *l_lwpctl; /* p: lwpctl block kernel address */ 129 struct lcpage *l_lcpage; /* p: lwpctl containing page */ 130 kcpuset_t *l_affinity; /* l: CPU set for affinity */ 131 132 /* Synchronisation. */ 133 struct syncobj *l_syncobj; /* l: sync object operations set */ 134 LIST_ENTRY(lwp) l_sleepchain; /* l: sleep queue */ 135 wchan_t l_wchan; /* l: sleep address */ 136 const char *l_wmesg; /* l: reason for sleep */ 137 struct sleepq *l_sleepq; /* l: current sleep queue */ 138 callout_t l_timeout_ch; /* !: callout for tsleep */ 139 kcondvar_t l_waitcv; /* a: vfork() wait */ 140 u_int l_slptime; /* l: time since last blocked */ 141 bool l_vforkwaiting; /* a: vfork() waiting */ 142 143 /* User-space synchronization. */ 144 uintptr_t l_robust_head; /* !: list of robust futexes */ 145 uint32_t l___rsvd1; /* reserved for future use */ 146 147 #if PCU_UNIT_COUNT > 0 148 struct cpu_info * volatile l_pcu_cpu[PCU_UNIT_COUNT]; 149 uint32_t l_pcu_valid; 150 #endif 151 152 /* Process level and global state, misc. */ 153 lwpid_t l_lid; /* (: LWP identifier; local to proc */ 154 LIST_ENTRY(lwp) l_list; /* a: entry on list of all LWPs */ 155 void *l_ctxlink; /* p: uc_link {get,set}context */ 156 struct proc *l_proc; /* p: parent process */ 157 LIST_ENTRY(lwp) l_sibling; /* p: entry on proc's list of LWPs */ 158 char *l_name; /* (: name, optional */ 159 lwpid_t l_waiter; /* p: first LWP waiting on us */ 160 lwpid_t l_waitingfor; /* p: specific LWP we are waiting on */ 161 int l_prflag; /* p: process level flags */ 162 u_int l_refcnt; /* p: reference count on this LWP */ 163 164 /* State of select() or poll(). */ 165 int l_selflag; /* S: polling state flags */ 166 int l_selret; /* S: return value of select/poll */ 167 SLIST_HEAD(,selinfo) l_selwait; /* S: descriptors waited on */ 168 uintptr_t l_selrec; /* !: argument for selrecord() */ 169 struct selcluster *l_selcluster;/* !: associated cluster data */ 170 void * l_selbits; /* (: select() bit-field */ 171 size_t l_selni; /* (: size of a single bit-field */ 172 173 /* Signals. */ 174 int l_sigrestore; /* p: need to restore old sig mask */ 175 sigset_t l_sigwaitset; /* p: signals being waited for */ 176 kcondvar_t l_sigcv; /* p: for sigsuspend() */ 177 struct ksiginfo *l_sigwaited; /* p: delivered signals from set */ 178 sigpend_t *l_sigpendset; /* p: XXX issignal()/postsig() baton */ 179 LIST_ENTRY(lwp) l_sigwaiter; /* p: chain on list of waiting LWPs */ 180 stack_t l_sigstk; /* p: sp & on stack state variable */ 181 sigset_t l_sigmask; /* p: signal mask */ 182 sigpend_t l_sigpend; /* p: signals to this LWP */ 183 sigset_t l_sigoldmask; /* p: mask for sigpause */ 184 185 /* Private data. */ 186 specificdata_reference 187 l_specdataref; /* !: subsystem lwp-specific data */ 188 struct timespec l_ktrcsw; /* !: for ktrace CSW trace XXX */ 189 void *l_private; /* !: svr4-style lwp-private data */ 190 struct lwp *l_switchto; /* !: mi_switch: switch to this LWP */ 191 struct kauth_cred *l_cred; /* !: cached credentials */ 192 struct filedesc *l_fd; /* !: cached copy of proc::p_fd */ 193 void *l_emuldata; /* !: kernel lwp-private data */ 194 struct fstrans_lwp_info *l_fstrans; /* (: fstrans private data */ 195 u_short l_shlocks; /* !: lockdebug: shared locks held */ 196 u_short l_exlocks; /* !: lockdebug: excl. locks held */ 197 u_short l_psrefs; /* !: count of psref held */ 198 u_short l_blcnt; /* !: count of kernel_lock held */ 199 volatile int l_nopreempt; /* !: don't preempt me! */ 200 volatile u_int l_dopreempt; /* s: kernel preemption pending */ 201 int l_pflag; /* !: LWP private flags */ 202 int l_dupfd; /* !: side return from cloning devs XXX */ 203 const struct sysent * volatile l_sysent;/* !: currently active syscall */ 204 struct rusage l_ru; /* !: accounting information */ 205 uint64_t l_pfailtime; /* !: for kernel preemption */ 206 uintptr_t l_pfailaddr; /* !: for kernel preemption */ 207 uintptr_t l_pfaillock; /* !: for kernel preemption */ 208 _TAILQ_HEAD(,struct lockdebug,volatile) l_ld_locks;/* !: locks held by LWP */ 209 volatile void *l_ld_wanted; /* !: lock currently wanted by LWP */ 210 uintptr_t l_rwcallsite; /* !: rwlock actual callsite */ 211 int l_tcgen; /* !: for timecounter removal */ 212 213 /* These are only used by 'options SYSCALL_TIMES'. */ 214 uint32_t l_syscall_time; /* !: time epoch for current syscall */ 215 uint64_t *l_syscall_counter; /* !: counter for current process */ 216 217 struct kdtrace_thread *l_dtrace; /* (: DTrace-specific data. */ 218 219 #ifdef KMSAN 220 void *l_kmsan; /* !: KMSAN private data. */ 221 #endif 222 #ifdef KCOV 223 void *l_kcov; /* !: KCOV private data. */ 224 #endif 225 }; 226 227 /* 228 * UAREA_PCB_OFFSET: an offset of PCB structure in the uarea. MD code may 229 * define it in <machine/proc.h>, to indicate a different uarea layout. 230 */ 231 #ifndef UAREA_PCB_OFFSET 232 #define UAREA_PCB_OFFSET 0 233 #endif 234 235 LIST_HEAD(lwplist, lwp); /* A list of LWPs. */ 236 237 #ifdef _KERNEL 238 extern struct lwplist alllwp; /* List of all LWPs. */ 239 extern lwp_t lwp0; /* LWP for proc0. */ 240 extern int maxlwp __read_mostly; /* max number of lwps */ 241 #ifndef MAXLWP 242 #define MAXLWP 2048 243 #endif 244 #ifndef __HAVE_CPU_MAXLWP 245 #define cpu_maxlwp() MAXLWP 246 #endif 247 #endif 248 249 #endif /* _KERNEL || _KMEMUSER */ 250 251 /* 252 * These flags are kept in l_flag, and they are modified only with the LWP 253 * locked. 254 */ 255 #define LW_IDLE 0x00000001 /* Idle lwp. */ 256 #define LW_LWPCTL 0x00000002 /* Adjust lwpctl in userret */ 257 #define LW_STIMO 0x00000040 /* Sleep timed out */ 258 #define LW_SINTR 0x00000080 /* Sleep is interruptible. */ 259 #define LW_CATCHINTR 0x00000100 /* LW_SINTR intent; see sleepq_block(). */ 260 #define LW_SYSTEM 0x00000200 /* Kernel thread */ 261 #define LW_SYSTEM_FPU 0x00000400 /* Kernel thread with vector/FP enabled */ 262 #define LW_DBGSUSPEND 0x00010000 /* Suspend by debugger */ 263 #define LW_WSUSPEND 0x00020000 /* Suspend before return to user */ 264 #define LW_BATCH 0x00040000 /* LWP tends to hog CPU */ 265 #define LW_WCORE 0x00080000 /* Stop for core dump on return to user */ 266 #define LW_WEXIT 0x00100000 /* Exit before return to user */ 267 #define LW_PENDSIG 0x01000000 /* Pending signal for us */ 268 #define LW_CANCELLED 0x02000000 /* tsleep should not sleep */ 269 #define LW_WREBOOT 0x08000000 /* System is rebooting, please suspend */ 270 #define LW_UNPARKED 0x10000000 /* Unpark op pending */ 271 #define LW_RUMP_CLEAR 0x40000000 /* Clear curlwp in RUMP scheduler */ 272 #define LW_RUMP_QEXIT 0x80000000 /* LWP should exit ASAP */ 273 274 /* 275 * The second set of flags is kept in l_pflag, and they are modified only by 276 * the LWP itself, or modified when it's known the LWP cannot be running. 277 * LP_RUNNING is typically updated with the LWP locked, but not always in 278 * the case of soft interrupt handlers. 279 */ 280 #define LP_KTRACTIVE 0x00000001 /* Executing ktrace operation */ 281 #define LP_KTRCSW 0x00000002 /* ktrace context switch marker */ 282 #define LP_KTRCSWUSER 0x00000004 /* ktrace context switch marker */ 283 /* 0x00000008 was LP_PIDLID */ 284 #define LP_OWEUPC 0x00000010 /* Owe user profiling tick */ 285 #define LP_MPSAFE 0x00000020 /* Starts life without kernel_lock */ 286 #define LP_INTR 0x00000040 /* Soft interrupt handler */ 287 #define LP_SYSCTLWRITE 0x00000080 /* sysctl write lock held */ 288 #define LP_MUSTJOIN 0x00000100 /* Must join kthread on exit */ 289 #define LP_SINGLESTEP 0x00000400 /* Single step thread in ptrace(2) */ 290 #define LP_TIMEINTR 0x00010000 /* Time this soft interrupt */ 291 #define LP_PREEMPTING 0x00020000 /* mi_switch called involuntarily */ 292 #define LP_RUNNING 0x20000000 /* Active on a CPU */ 293 #define LP_TELEPORT 0x40000000 /* Teleport to new CPU on preempt() */ 294 #define LP_BOUND 0x80000000 /* Bound to a CPU */ 295 296 /* 297 * The third set of flags is kept in l_prflag and they are modified only 298 * with p_lock held. 299 */ 300 #define LPR_DETACHED 0x00800000 /* Won't be waited for. */ 301 #define LPR_CRMOD 0x00000100 /* Credentials modified */ 302 #define LPR_DRAINING 0x80000000 /* Draining references before exiting */ 303 304 /* 305 * Mask indicating that there is "exceptional" work to be done on return to 306 * user. 307 */ 308 #define LW_USERRET \ 309 (LW_WEXIT | LW_PENDSIG | LW_WREBOOT | LW_WSUSPEND | LW_WCORE | LW_LWPCTL) 310 311 /* 312 * Status values. 313 * 314 * A note about LSRUN and LSONPROC: LSRUN indicates that a process is 315 * runnable but *not* yet running, i.e. is on a run queue. LSONPROC 316 * indicates that the process is actually executing on a CPU, i.e. 317 * it is no longer on a run queue. 318 * 319 * These values are set in stone and must not be reused with future changes. 320 */ 321 #define LSIDL 1 /* Process being created by fork. */ 322 #define LSRUN 2 /* Currently runnable. */ 323 #define LSSLEEP 3 /* Sleeping on an address. */ 324 #define LSSTOP 4 /* Process debugging or suspension. */ 325 #define LSZOMB 5 /* Awaiting collection by parent. */ 326 /* define LSDEAD 6 Process is almost a zombie. (removed in 5.0) */ 327 #define LSONPROC 7 /* Process is currently on a CPU. */ 328 #define LSSUSPENDED 8 /* Not running, not signalable. */ 329 330 #if defined(_KERNEL) || defined(_KMEMUSER) 331 static __inline void * 332 lwp_getpcb(struct lwp *l) 333 { 334 335 return l->l_addr; 336 } 337 #endif /* _KERNEL || _KMEMUSER */ 338 339 #ifdef _KERNEL 340 #define LWP_CACHE_CREDS(l, p) \ 341 do { \ 342 (void)p; \ 343 if (__predict_false((l)->l_prflag & LPR_CRMOD)) \ 344 lwp_update_creds(l); \ 345 } while (/* CONSTCOND */ 0) 346 347 void lwpinit(void); 348 void lwp0_init(void); 349 350 void lwp_startup(lwp_t *, lwp_t *); 351 void startlwp(void *); 352 353 int lwp_locked(lwp_t *, kmutex_t *); 354 kmutex_t *lwp_setlock(lwp_t *, kmutex_t *); 355 void lwp_unlock_to(lwp_t *, kmutex_t *); 356 int lwp_trylock(lwp_t *); 357 void lwp_addref(lwp_t *); 358 void lwp_delref(lwp_t *); 359 void lwp_delref2(lwp_t *); 360 bool lwp_drainrefs(lwp_t *); 361 bool lwp_alive(lwp_t *); 362 lwp_t *lwp_find_first(proc_t *); 363 364 int lwp_wait(lwp_t *, lwpid_t, lwpid_t *, bool); 365 void lwp_continue(lwp_t *); 366 void lwp_unsleep(lwp_t *, bool); 367 void lwp_unstop(lwp_t *); 368 void lwp_exit(lwp_t *); 369 int lwp_suspend(lwp_t *, lwp_t *); 370 int lwp_create1(lwp_t *, const void *, size_t, u_long, lwpid_t *); 371 void lwp_start(lwp_t *, int); 372 void lwp_update_creds(lwp_t *); 373 void lwp_migrate(lwp_t *, struct cpu_info *); 374 lwp_t * lwp_find2(pid_t, lwpid_t); 375 lwp_t * lwp_find(proc_t *, int); 376 void lwp_userret(lwp_t *); 377 void lwp_need_userret(lwp_t *); 378 void lwp_free(lwp_t *, bool, bool); 379 uint64_t lwp_pctr(void); 380 int lwp_setprivate(lwp_t *, void *); 381 int do_lwp_create(lwp_t *, void *, u_long, lwp_t **, const sigset_t *, 382 const stack_t *); 383 384 void lwp_thread_cleanup(lwp_t *); 385 386 void lwpinit_specificdata(void); 387 int lwp_specific_key_create(specificdata_key_t *, specificdata_dtor_t); 388 void lwp_specific_key_delete(specificdata_key_t); 389 void lwp_initspecific(lwp_t *); 390 void lwp_finispecific(lwp_t *); 391 void *lwp_getspecific(specificdata_key_t); 392 #if defined(_LWP_API_PRIVATE) 393 void *_lwp_getspecific_by_lwp(lwp_t *, specificdata_key_t); 394 #endif 395 void lwp_setspecific(specificdata_key_t, void *); 396 void lwp_setspecific_by_lwp(lwp_t *, specificdata_key_t, void *); 397 398 /* Syscalls. */ 399 int lwp_park(clockid_t, int, struct timespec *); 400 int lwp_unpark(const lwpid_t *, const u_int); 401 402 /* DDB. */ 403 void lwp_whatis(uintptr_t, void (*)(const char *, ...) __printflike(1, 2)); 404 405 /* 406 * Lock an LWP. XXX _MODULE 407 */ 408 static __inline void 409 lwp_lock(lwp_t *l) 410 { 411 kmutex_t *old = atomic_load_consume(&l->l_mutex); 412 413 /* 414 * Note: mutex_spin_enter() will have posted a read barrier. 415 * Re-test l->l_mutex. If it has changed, we need to try again. 416 */ 417 mutex_spin_enter(old); 418 while (__predict_false(atomic_load_relaxed(&l->l_mutex) != old)) { 419 mutex_spin_exit(old); 420 old = atomic_load_consume(&l->l_mutex); 421 mutex_spin_enter(old); 422 } 423 } 424 425 /* 426 * Unlock an LWP. XXX _MODULE 427 */ 428 static __inline void 429 lwp_unlock(lwp_t *l) 430 { 431 mutex_spin_exit(l->l_mutex); 432 } 433 434 static __inline void 435 lwp_changepri(lwp_t *l, pri_t pri) 436 { 437 KASSERT(mutex_owned(l->l_mutex)); 438 439 if (l->l_priority == pri) 440 return; 441 442 (*l->l_syncobj->sobj_changepri)(l, pri); 443 KASSERT(l->l_priority == pri); 444 } 445 446 static __inline void 447 lwp_lendpri(lwp_t *l, pri_t pri) 448 { 449 KASSERT(mutex_owned(l->l_mutex)); 450 451 (*l->l_syncobj->sobj_lendpri)(l, pri); 452 KASSERT(l->l_inheritedprio == pri); 453 } 454 455 static __inline pri_t 456 lwp_eprio(lwp_t *l) 457 { 458 pri_t pri; 459 460 pri = l->l_priority; 461 if ((l->l_flag & LW_SYSTEM) == 0 && l->l_kpriority && pri < PRI_KERNEL) 462 pri = (pri >> 1) + l->l_kpribase; 463 return MAX(l->l_auxprio, pri); 464 } 465 466 int lwp_create(lwp_t *, struct proc *, vaddr_t, int, void *, size_t, 467 void (*)(void *), void *, lwp_t **, int, const sigset_t *, const stack_t *); 468 469 /* 470 * XXX _MODULE 471 * We should provide real stubs for the below that modules can use. 472 */ 473 474 static __inline void 475 spc_lock(struct cpu_info *ci) 476 { 477 mutex_spin_enter(ci->ci_schedstate.spc_mutex); 478 } 479 480 static __inline void 481 spc_unlock(struct cpu_info *ci) 482 { 483 mutex_spin_exit(ci->ci_schedstate.spc_mutex); 484 } 485 486 static __inline void 487 spc_dlock(struct cpu_info *ci1, struct cpu_info *ci2) 488 { 489 struct schedstate_percpu *spc1 = &ci1->ci_schedstate; 490 struct schedstate_percpu *spc2 = &ci2->ci_schedstate; 491 492 KASSERT(ci1 != ci2); 493 if (ci1 < ci2) { 494 mutex_spin_enter(spc1->spc_mutex); 495 mutex_spin_enter(spc2->spc_mutex); 496 } else { 497 mutex_spin_enter(spc2->spc_mutex); 498 mutex_spin_enter(spc1->spc_mutex); 499 } 500 } 501 502 /* 503 * Allow machine-dependent code to override curlwp in <machine/cpu.h> for 504 * its own convenience. Otherwise, we declare it as appropriate. 505 */ 506 #if !defined(curlwp) 507 #if defined(MULTIPROCESSOR) 508 #define curlwp curcpu()->ci_curlwp /* Current running LWP */ 509 #else 510 extern struct lwp *curlwp; /* Current running LWP */ 511 #endif /* MULTIPROCESSOR */ 512 #endif /* ! curlwp */ 513 #define curproc (curlwp->l_proc) 514 515 /* 516 * This provides a way for <machine/cpu.h> to get l_cpu for curlwp before 517 * struct lwp is defined. 518 */ 519 static __inline struct cpu_info * 520 lwp_getcpu(struct lwp *l) 521 { 522 return l->l_cpu; 523 } 524 525 static __inline bool 526 CURCPU_IDLE_P(void) 527 { 528 struct cpu_info *ci = curcpu(); 529 return ci->ci_onproc == ci->ci_data.cpu_idlelwp; 530 } 531 532 /* 533 * Disable and re-enable preemption. Only for low-level kernel 534 * use. Device drivers and anything that could potentially be 535 * compiled as a module should use kpreempt_disable() and 536 * kpreempt_enable(). 537 */ 538 static __inline void 539 KPREEMPT_DISABLE(lwp_t *l) 540 { 541 542 KASSERT(l == curlwp); 543 l->l_nopreempt++; 544 __insn_barrier(); 545 } 546 547 static __inline void 548 KPREEMPT_ENABLE(lwp_t *l) 549 { 550 551 KASSERT(l == curlwp); 552 KASSERT(l->l_nopreempt > 0); 553 __insn_barrier(); 554 if (--l->l_nopreempt != 0) 555 return; 556 __insn_barrier(); 557 if (__predict_false(l->l_dopreempt)) 558 kpreempt(0); 559 __insn_barrier(); 560 } 561 562 /* For lwp::l_dopreempt */ 563 #define DOPREEMPT_ACTIVE 0x01 564 #define DOPREEMPT_COUNTED 0x02 565 566 /* 567 * Prevent curlwp from migrating between CPUs between curlwp_bind and 568 * curlwp_bindx. One use case is psref(9) that has a contract that 569 * forbids migrations. 570 */ 571 static __inline int 572 curlwp_bind(void) 573 { 574 int bound; 575 576 bound = curlwp->l_pflag & LP_BOUND; 577 curlwp->l_pflag |= LP_BOUND; 578 __insn_barrier(); 579 580 return bound; 581 } 582 583 static __inline void 584 curlwp_bindx(int bound) 585 { 586 587 KASSERT(curlwp->l_pflag & LP_BOUND); 588 __insn_barrier(); 589 curlwp->l_pflag ^= bound ^ LP_BOUND; 590 } 591 592 #endif /* _KERNEL */ 593 594 /* Flags for _lwp_create(), as per Solaris. */ 595 #define LWP_DETACHED 0x00000040 596 #define LWP_SUSPENDED 0x00000080 597 598 /* Kernel-internal flags for LWP creation. */ 599 /* 0x40000000 was LWP_PIDLID */ 600 #define LWP_VFORK 0x80000000 601 602 #endif /* !_SYS_LWP_H_ */ 603