sys/dev/hwpmc/hwpmc_logging.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2005-2007 Joseph Koshy
   5  * Copyright (c) 2007 The FreeBSD Foundation
   6  * Copyright (c) 2018 Matthew Macy
   7  * All rights reserved.
   8  *
   9  * Portions of this software were developed by A. Joseph Koshy under
  10  * sponsorship from the FreeBSD Foundation and Google, Inc.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  */
  34
  35 /*
  36  * Logging code for hwpmc(4)
  37  */
  38
  39 #include <sys/cdefs.h>
  40 __FBSDID("$FreeBSD$");
  41
  42 #include <sys/param.h>
  43 #include <sys/capsicum.h>
  44 #include <sys/file.h>
  45 #include <sys/kernel.h>
  46 #include <sys/kthread.h>
  47 #include <sys/lock.h>
  48 #include <sys/module.h>
  49 #include <sys/mutex.h>
  50 #include <sys/pmc.h>
  51 #include <sys/pmckern.h>
  52 #include <sys/pmclog.h>
  53 #include <sys/proc.h>
  54 #include <sys/sched.h>
  55 #include <sys/signalvar.h>
  56 #include <sys/smp.h>
  57 #include <sys/syscallsubr.h>
  58 #include <sys/sysctl.h>
  59 #include <sys/systm.h>
  60 #include <sys/uio.h>
  61 #include <sys/unistd.h>
  62 #include <sys/vnode.h>
  63
  64 #if defined(__i386__) || defined(__amd64__)
  65 #include <machine/clock.h>
  66 #endif
  67
  68 #define curdomain PCPU_GET(domain)
  69
  70 /*
  71  * Sysctl tunables
  72  */
  73
  74 SYSCTL_DECL(_kern_hwpmc);
  75
  76 /*
  77  * kern.hwpmc.logbuffersize -- size of the per-cpu owner buffers.
  78  */
  79
  80 static int pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
  81 #if (__FreeBSD_version < 1100000)
  82 TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "logbuffersize", &pmclog_buffer_size);
  83 #endif
  84 SYSCTL_INT(_kern_hwpmc, OID_AUTO, logbuffersize, CTLFLAG_RDTUN,
  85     &pmclog_buffer_size, 0, "size of log buffers in kilobytes");
  86
  87 /*
  88  * kern.hwpmc.nbuffer -- number of global log buffers
  89  */
  90
  91 static int pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
  92 #if (__FreeBSD_version < 1100000)
  93 TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "nbuffers", &pmc_nlogbuffers_pcpu);
  94 #endif
  95 SYSCTL_INT(_kern_hwpmc, OID_AUTO, nbuffers_pcpu, CTLFLAG_RDTUN,
  96     &pmc_nlogbuffers_pcpu, 0, "number of log buffers per cpu");
  97
  98 /*
  99  * Global log buffer list and associated spin lock.
 100  */
 101
 102 static struct mtx pmc_kthread_mtx;      /* sleep lock */
 103
 104 #define PMCLOG_INIT_BUFFER_DESCRIPTOR(D, buf, domain) do {                                              \
 105                 (D)->plb_fence = ((char *) (buf)) +     1024*pmclog_buffer_size;                        \
 106                 (D)->plb_base  = (D)->plb_ptr = ((char *) (buf));                               \
 107                 (D)->plb_domain = domain; \
 108         } while (0)
 109
 110 #define PMCLOG_RESET_BUFFER_DESCRIPTOR(D) do {                  \
 111                 (D)->plb_ptr  = (D)->plb_base; \
 112         } while (0)
 113
 114 /*
 115  * Log file record constructors.
 116  */
 117 #define _PMCLOG_TO_HEADER(T,L)                                          \
 118         ((PMCLOG_HEADER_MAGIC << 24) |                                  \
 119          (PMCLOG_TYPE_ ## T << 16)   |                                  \
 120          ((L) & 0xFFFF))
 121
 122 /* reserve LEN bytes of space and initialize the entry header */
 123 #define _PMCLOG_RESERVE_SAFE(PO,TYPE,LEN,ACTION, TSC) do {      \
 124                 uint32_t *_le;                                          \
 125                 int _len = roundup((LEN), sizeof(uint32_t));    \
 126                 struct pmclog_header *ph;                                                       \
 127                 if ((_le = pmclog_reserve((PO), _len)) == NULL) {       \
 128                         ACTION;                                                                                 \
 129                 }                                                                                                       \
 130                 ph = (struct pmclog_header *)_le;                                       \
 131                 ph->pl_header =_PMCLOG_TO_HEADER(TYPE,_len);    \
 132                 ph->pl_tsc = (TSC);                                                                     \
 133                 _le += sizeof(*ph)/4    /* skip over timestamp */
 134
 135 /* reserve LEN bytes of space and initialize the entry header */
 136 #define _PMCLOG_RESERVE(PO,TYPE,LEN,ACTION) do {                        \
 137                 uint32_t *_le;                                          \
 138                 int _len = roundup((LEN), sizeof(uint32_t));    \
 139                 uint64_t tsc;                                                                           \
 140                 struct pmclog_header *ph;                                                       \
 141                 tsc = pmc_rdtsc();                                                                      \
 142                 spinlock_enter();                                                                       \
 143                 if ((_le = pmclog_reserve((PO), _len)) == NULL) {       \
 144                         spinlock_exit();                                                                \
 145                         ACTION;                                                                                 \
 146                 }                                                                                               \
 147                 ph = (struct pmclog_header *)_le;                                       \
 148                 ph->pl_header =_PMCLOG_TO_HEADER(TYPE,_len);    \
 149                 ph->pl_tsc = tsc;                                                                       \
 150                 _le += sizeof(*ph)/4    /* skip over timestamp */
 151
 152
 153
 154 #define PMCLOG_RESERVE_SAFE(P,T,L,TSC)          _PMCLOG_RESERVE_SAFE(P,T,L,return,TSC)
 155 #define PMCLOG_RESERVE(P,T,L)           _PMCLOG_RESERVE(P,T,L,return)
 156 #define PMCLOG_RESERVE_WITH_ERROR(P,T,L) _PMCLOG_RESERVE(P,T,L,         \
 157         error=ENOMEM;goto error)
 158
 159 #define PMCLOG_EMIT32(V)        do { *_le++ = (V); } while (0)
 160 #define PMCLOG_EMIT64(V)        do {                                    \
 161                 *_le++ = (uint32_t) ((V) & 0xFFFFFFFF);                 \
 162                 *_le++ = (uint32_t) (((V) >> 32) & 0xFFFFFFFF);         \
 163         } while (0)
 164
 165
 166 /* Emit a string.  Caution: does NOT update _le, so needs to be last */
 167 #define PMCLOG_EMITSTRING(S,L)  do { bcopy((S), _le, (L)); } while (0)
 168 #define PMCLOG_EMITNULLSTRING(L) do { bzero(_le, (L)); } while (0)
 169
 170 #define PMCLOG_DESPATCH_SAFE(PO)                                                \
 171             pmclog_release((PO));                                               \
 172         } while (0)
 173
 174 #define PMCLOG_DESPATCH_SCHED_LOCK(PO)                                          \
 175              pmclog_release_flags((PO), 0);                                                     \
 176         } while (0)
 177
 178 #define PMCLOG_DESPATCH(PO)                                                     \
 179             pmclog_release((PO));                                               \
 180                 spinlock_exit();                                                        \
 181         } while (0)
 182
 183 #define PMCLOG_DESPATCH_SYNC(PO)                                                \
 184             pmclog_schedule_io((PO), 1);                                                \
 185                 spinlock_exit();                                                                \
 186                 } while (0)
 187
 188
 189 #define TSDELTA 4
 190 /*
 191  * Assertions about the log file format.
 192  */
 193 CTASSERT(sizeof(struct pmclog_callchain) == 7*4 + TSDELTA +
 194     PMC_CALLCHAIN_DEPTH_MAX*sizeof(uintfptr_t));
 195 CTASSERT(sizeof(struct pmclog_closelog) == 3*4 + TSDELTA);
 196 CTASSERT(sizeof(struct pmclog_dropnotify) == 3*4 + TSDELTA);
 197 CTASSERT(sizeof(struct pmclog_map_in) == PATH_MAX + TSDELTA +
 198     5*4 + sizeof(uintfptr_t));
 199 CTASSERT(offsetof(struct pmclog_map_in,pl_pathname) ==
 200     5*4 + TSDELTA + sizeof(uintfptr_t));
 201 CTASSERT(sizeof(struct pmclog_map_out) == 5*4 + 2*sizeof(uintfptr_t) + TSDELTA);
 202 CTASSERT(sizeof(struct pmclog_pmcallocate) == 9*4 + TSDELTA);
 203 CTASSERT(sizeof(struct pmclog_pmcattach) == 5*4 + PATH_MAX + TSDELTA);
 204 CTASSERT(offsetof(struct pmclog_pmcattach,pl_pathname) == 5*4 + TSDELTA);
 205 CTASSERT(sizeof(struct pmclog_pmcdetach) == 5*4 + TSDELTA);
 206 CTASSERT(sizeof(struct pmclog_proccsw) == 7*4 + 8 + TSDELTA);
 207 CTASSERT(sizeof(struct pmclog_procexec) == 5*4 + PATH_MAX +
 208     sizeof(uintfptr_t) + TSDELTA);
 209 CTASSERT(offsetof(struct pmclog_procexec,pl_pathname) == 5*4 + TSDELTA +
 210     sizeof(uintfptr_t));
 211 CTASSERT(sizeof(struct pmclog_procexit) == 5*4 + 8 + TSDELTA);
 212 CTASSERT(sizeof(struct pmclog_procfork) == 5*4 + TSDELTA);
 213 CTASSERT(sizeof(struct pmclog_sysexit) == 6*4);
 214 CTASSERT(sizeof(struct pmclog_userdata) == 6*4);
 215
 216 /*
 217  * Log buffer structure
 218  */
 219
 220 struct pmclog_buffer {
 221         TAILQ_ENTRY(pmclog_buffer) plb_next;
 222         char            *plb_base;
 223         char            *plb_ptr;
 224         char            *plb_fence;
 225         uint16_t         plb_domain;
 226 } __aligned(CACHE_LINE_SIZE);
 227
 228 /*
 229  * Prototypes
 230  */
 231
 232 static int pmclog_get_buffer(struct pmc_owner *po);
 233 static void pmclog_loop(void *arg);
 234 static void pmclog_release(struct pmc_owner *po);
 235 static uint32_t *pmclog_reserve(struct pmc_owner *po, int length);
 236 static void pmclog_schedule_io(struct pmc_owner *po, int wakeup);
 237 static void pmclog_schedule_all(struct pmc_owner *po);
 238 static void pmclog_stop_kthread(struct pmc_owner *po);
 239
 240 /*
 241  * Helper functions
 242  */
 243
 244 static inline void
 245 pmc_plb_rele_unlocked(struct pmclog_buffer *plb)
 246 {
 247         TAILQ_INSERT_HEAD(&pmc_dom_hdrs[plb->plb_domain]->pdbh_head, plb, plb_next);
 248 }
 249
 250 static inline void
 251 pmc_plb_rele(struct pmclog_buffer *plb)
 252 {
 253         mtx_lock_spin(&pmc_dom_hdrs[plb->plb_domain]->pdbh_mtx);
 254         pmc_plb_rele_unlocked(plb);
 255         mtx_unlock_spin(&pmc_dom_hdrs[plb->plb_domain]->pdbh_mtx);
 256 }
 257
 258 /*
 259  * Get a log buffer
 260  */
 261 static int
 262 pmclog_get_buffer(struct pmc_owner *po)
 263 {
 264         struct pmclog_buffer *plb;
 265         int domain;
 266
 267         KASSERT(po->po_curbuf[curcpu] == NULL,
 268             ("[pmclog,%d] po=%p current buffer still valid", __LINE__, po));
 269
 270         domain = curdomain;
 271         MPASS(pmc_dom_hdrs[domain]);
 272         mtx_lock_spin(&pmc_dom_hdrs[domain]->pdbh_mtx);
 273         if ((plb = TAILQ_FIRST(&pmc_dom_hdrs[domain]->pdbh_head)) != NULL)
 274                 TAILQ_REMOVE(&pmc_dom_hdrs[domain]->pdbh_head, plb, plb_next);
 275         mtx_unlock_spin(&pmc_dom_hdrs[domain]->pdbh_mtx);
 276
 277         PMCDBG2(LOG,GTB,1, "po=%p plb=%p", po, plb);
 278
 279 #ifdef  HWPMC_DEBUG
 280         if (plb)
 281                 KASSERT(plb->plb_ptr == plb->plb_base &&
 282                     plb->plb_base < plb->plb_fence,
 283                     ("[pmclog,%d] po=%p buffer invariants: ptr=%p "
 284                     "base=%p fence=%p", __LINE__, po, plb->plb_ptr,
 285                     plb->plb_base, plb->plb_fence));
 286 #endif
 287
 288         po->po_curbuf[curcpu] = plb;
 289
 290         /* update stats */
 291         counter_u64_add(pmc_stats.pm_buffer_requests, 1);
 292         if (plb == NULL)
 293                 counter_u64_add(pmc_stats.pm_buffer_requests_failed, 1);
 294
 295         return (plb ? 0 : ENOMEM);
 296 }
 297
 298 struct pmclog_proc_init_args {
 299         struct proc *kthr;
 300         struct pmc_owner *po;
 301         bool exit;
 302         bool acted;
 303 };
 304
 305 int
 306 pmclog_proc_create(struct thread *td, void **handlep)
 307 {
 308         struct pmclog_proc_init_args *ia;
 309         int error;
 310
 311         ia = malloc(sizeof(*ia), M_TEMP, M_WAITOK | M_ZERO);
 312         error = kproc_create(pmclog_loop, ia, &ia->kthr,
 313             RFHIGHPID, 0, "hwpmc: proc(%d)", td->td_proc->p_pid);
 314         if (error == 0)
 315                 *handlep = ia;
 316         return (error);
 317 }
 318
 319 void
 320 pmclog_proc_ignite(void *handle, struct pmc_owner *po)
 321 {
 322         struct pmclog_proc_init_args *ia;
 323
 324         ia = handle;
 325         mtx_lock(&pmc_kthread_mtx);
 326         MPASS(!ia->acted);
 327         MPASS(ia->po == NULL);
 328         MPASS(!ia->exit);
 329         MPASS(ia->kthr != NULL);
 330         if (po == NULL) {
 331                 ia->exit = true;
 332         } else {
 333                 ia->po = po;
 334                 KASSERT(po->po_kthread == NULL,
 335                     ("[pmclog,%d] po=%p kthread (%p) already present",
 336                     __LINE__, po, po->po_kthread));
 337                 po->po_kthread = ia->kthr;
 338         }
 339         wakeup(ia);
 340         while (!ia->acted)
 341                 msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogw", 0);
 342         mtx_unlock(&pmc_kthread_mtx);
 343         free(ia, M_TEMP);
 344 }
 345
 346 /*
 347  * Log handler loop.
 348  *
 349  * This function is executed by each pmc owner's helper thread.
 350  */
 351 static void
 352 pmclog_loop(void *arg)
 353 {
 354         struct pmclog_proc_init_args *ia;
 355         struct pmc_owner *po;
 356         struct pmclog_buffer *lb;
 357         struct proc *p;
 358         struct ucred *ownercred;
 359         struct ucred *mycred;
 360         struct thread *td;
 361         sigset_t unb;
 362         struct uio auio;
 363         struct iovec aiov;
 364         size_t nbytes;
 365         int error;
 366
 367         td = curthread;
 368
 369         SIGEMPTYSET(unb);
 370         SIGADDSET(unb, SIGHUP);
 371         (void)kern_sigprocmask(td, SIG_UNBLOCK, &unb, NULL, 0);
 372
 373         ia = arg;
 374         MPASS(ia->kthr == curproc);
 375         MPASS(!ia->acted);
 376         mtx_lock(&pmc_kthread_mtx);
 377         while (ia->po == NULL && !ia->exit)
 378                 msleep(ia, &pmc_kthread_mtx, PWAIT, "pmclogi", 0);
 379         if (ia->exit) {
 380                 ia->acted = true;
 381                 wakeup(ia);
 382                 mtx_unlock(&pmc_kthread_mtx);
 383                 kproc_exit(0);
 384         }
 385         MPASS(ia->po != NULL);
 386         po = ia->po;
 387         ia->acted = true;
 388         wakeup(ia);
 389         mtx_unlock(&pmc_kthread_mtx);
 390         ia = NULL;
 391
 392         p = po->po_owner;
 393         mycred = td->td_ucred;
 394
 395         PROC_LOCK(p);
 396         ownercred = crhold(p->p_ucred);
 397         PROC_UNLOCK(p);
 398
 399         PMCDBG2(LOG,INI,1, "po=%p kt=%p", po, po->po_kthread);
 400         KASSERT(po->po_kthread == curthread->td_proc,
 401             ("[pmclog,%d] proc mismatch po=%p po/kt=%p curproc=%p", __LINE__,
 402                 po, po->po_kthread, curthread->td_proc));
 403
 404         lb = NULL;
 405
 406
 407         /*
 408          * Loop waiting for I/O requests to be added to the owner
 409          * struct's queue.  The loop is exited when the log file
 410          * is deconfigured.
 411          */
 412
 413         mtx_lock(&pmc_kthread_mtx);
 414
 415         for (;;) {
 416
 417                 /* check if we've been asked to exit */
 418                 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
 419                         break;
 420
 421                 if (lb == NULL) { /* look for a fresh buffer to write */
 422                         mtx_lock_spin(&po->po_mtx);
 423                         if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) {
 424                                 mtx_unlock_spin(&po->po_mtx);
 425
 426                                 /* No more buffers and shutdown required. */
 427                                 if (po->po_flags & PMC_PO_SHUTDOWN)
 428                                         break;
 429
 430                                 (void) msleep(po, &pmc_kthread_mtx, PWAIT,
 431                                     "pmcloop", 250);
 432                                 continue;
 433                         }
 434
 435                         TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
 436                         mtx_unlock_spin(&po->po_mtx);
 437                 }
 438
 439                 mtx_unlock(&pmc_kthread_mtx);
 440
 441                 /* process the request */
 442                 PMCDBG3(LOG,WRI,2, "po=%p base=%p ptr=%p", po,
 443                     lb->plb_base, lb->plb_ptr);
 444                 /* change our thread's credentials before issuing the I/O */
 445
 446                 aiov.iov_base = lb->plb_base;
 447                 aiov.iov_len  = nbytes = lb->plb_ptr - lb->plb_base;
 448
 449                 auio.uio_iov    = &aiov;
 450                 auio.uio_iovcnt = 1;
 451                 auio.uio_offset = -1;
 452                 auio.uio_resid  = nbytes;
 453                 auio.uio_rw     = UIO_WRITE;
 454                 auio.uio_segflg = UIO_SYSSPACE;
 455                 auio.uio_td     = td;
 456
 457                 /* switch thread credentials -- see kern_ktrace.c */
 458                 td->td_ucred = ownercred;
 459                 error = fo_write(po->po_file, &auio, ownercred, 0, td);
 460                 td->td_ucred = mycred;
 461
 462                 if (error) {
 463                         /* XXX some errors are recoverable */
 464                         /* send a SIGIO to the owner and exit */
 465                         PROC_LOCK(p);
 466                         kern_psignal(p, SIGIO);
 467                         PROC_UNLOCK(p);
 468
 469                         mtx_lock(&pmc_kthread_mtx);
 470
 471                         po->po_error = error; /* save for flush log */
 472
 473                         PMCDBG2(LOG,WRI,2, "po=%p error=%d", po, error);
 474
 475                         break;
 476                 }
 477
 478                 mtx_lock(&pmc_kthread_mtx);
 479
 480                 /* put the used buffer back into the global pool */
 481                 PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
 482
 483                 pmc_plb_rele(lb);
 484                 lb = NULL;
 485         }
 486
 487         wakeup_one(po->po_kthread);
 488         po->po_kthread = NULL;
 489
 490         mtx_unlock(&pmc_kthread_mtx);
 491
 492         /* return the current I/O buffer to the global pool */
 493         if (lb) {
 494                 PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
 495
 496                 pmc_plb_rele(lb);
 497         }
 498
 499         /*
 500          * Exit this thread, signalling the waiter
 501          */
 502
 503         crfree(ownercred);
 504
 505         kproc_exit(0);
 506 }
 507
 508 /*
 509  * Release and log entry and schedule an I/O if needed.
 510  */
 511
 512 static void
 513 pmclog_release_flags(struct pmc_owner *po, int wakeup)
 514 {
 515         struct pmclog_buffer *plb;
 516
 517         plb = po->po_curbuf[curcpu];
 518         KASSERT(plb->plb_ptr >= plb->plb_base,
 519             ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
 520                 po, plb->plb_ptr, plb->plb_base));
 521         KASSERT(plb->plb_ptr <= plb->plb_fence,
 522             ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
 523                 po, plb->plb_ptr, plb->plb_fence));
 524
 525         /* schedule an I/O if we've filled a buffer */
 526         if (plb->plb_ptr >= plb->plb_fence)
 527                 pmclog_schedule_io(po, wakeup);
 528
 529         PMCDBG1(LOG,REL,1, "po=%p", po);
 530 }
 531
 532 static void
 533 pmclog_release(struct pmc_owner *po)
 534 {
 535
 536         pmclog_release_flags(po, 1);
 537 }
 538
 539
 540 /*
 541  * Attempt to reserve 'length' bytes of space in an owner's log
 542  * buffer.  The function returns a pointer to 'length' bytes of space
 543  * if there was enough space or returns NULL if no space was
 544  * available.  Non-null returns do so with the po mutex locked.  The
 545  * caller must invoke pmclog_release() on the pmc owner structure
 546  * when done.
 547  */
 548
 549 static uint32_t *
 550 pmclog_reserve(struct pmc_owner *po, int length)
 551 {
 552         uintptr_t newptr, oldptr;
 553         struct pmclog_buffer *plb, **pplb;
 554
 555         PMCDBG2(LOG,ALL,1, "po=%p len=%d", po, length);
 556
 557         KASSERT(length % sizeof(uint32_t) == 0,
 558             ("[pmclog,%d] length not a multiple of word size", __LINE__));
 559
 560         /* No more data when shutdown in progress. */
 561         if (po->po_flags & PMC_PO_SHUTDOWN)
 562                 return (NULL);
 563
 564         pplb = &po->po_curbuf[curcpu];
 565         if (*pplb == NULL && pmclog_get_buffer(po) != 0)
 566                 goto fail;
 567
 568         KASSERT(*pplb != NULL,
 569             ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
 570
 571         plb = *pplb;
 572         KASSERT(plb->plb_ptr >= plb->plb_base &&
 573             plb->plb_ptr <= plb->plb_fence,
 574             ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
 575                 __LINE__, po, plb->plb_ptr, plb->plb_base,
 576                 plb->plb_fence));
 577
 578         oldptr = (uintptr_t) plb->plb_ptr;
 579         newptr = oldptr + length;
 580
 581         KASSERT(oldptr != (uintptr_t) NULL,
 582             ("[pmclog,%d] po=%p Null log buffer pointer", __LINE__, po));
 583
 584         /*
 585          * If we have space in the current buffer, return a pointer to
 586          * available space with the PO structure locked.
 587          */
 588         if (newptr <= (uintptr_t) plb->plb_fence) {
 589                 plb->plb_ptr = (char *) newptr;
 590                 goto done;
 591         }
 592
 593         /*
 594          * Otherwise, schedule the current buffer for output and get a
 595          * fresh buffer.
 596          */
 597         pmclog_schedule_io(po, 0);
 598
 599         if (pmclog_get_buffer(po) != 0)
 600                 goto fail;
 601
 602         plb = *pplb;
 603         KASSERT(plb != NULL,
 604             ("[pmclog,%d] po=%p no current buffer", __LINE__, po));
 605
 606         KASSERT(plb->plb_ptr != NULL,
 607             ("[pmclog,%d] null return from pmc_get_log_buffer", __LINE__));
 608
 609         KASSERT(plb->plb_ptr == plb->plb_base &&
 610             plb->plb_ptr <= plb->plb_fence,
 611             ("[pmclog,%d] po=%p buffer invariants: ptr=%p base=%p fence=%p",
 612                 __LINE__, po, plb->plb_ptr, plb->plb_base,
 613                 plb->plb_fence));
 614
 615         oldptr = (uintptr_t) plb->plb_ptr;
 616
 617  done:
 618         return ((uint32_t *) oldptr);
 619  fail:
 620         return (NULL);
 621 }
 622
 623 /*
 624  * Schedule an I/O.
 625  *
 626  * Transfer the current buffer to the helper kthread.
 627  */
 628
 629 static void
 630 pmclog_schedule_io(struct pmc_owner *po, int wakeup)
 631 {
 632         struct pmclog_buffer *plb;
 633
 634         plb = po->po_curbuf[curcpu];
 635         po->po_curbuf[curcpu] = NULL;
 636         KASSERT(plb != NULL,
 637             ("[pmclog,%d] schedule_io with null buffer po=%p", __LINE__, po));
 638         KASSERT(plb->plb_ptr >= plb->plb_base,
 639             ("[pmclog,%d] buffer invariants po=%p ptr=%p base=%p", __LINE__,
 640                 po, plb->plb_ptr, plb->plb_base));
 641         KASSERT(plb->plb_ptr <= plb->plb_fence,
 642             ("[pmclog,%d] buffer invariants po=%p ptr=%p fenc=%p", __LINE__,
 643                 po, plb->plb_ptr, plb->plb_fence));
 644
 645         PMCDBG1(LOG,SIO, 1, "po=%p", po);
 646
 647         /*
 648          * Add the current buffer to the tail of the buffer list and
 649          * wakeup the helper.
 650          */
 651         mtx_lock_spin(&po->po_mtx);
 652         TAILQ_INSERT_TAIL(&po->po_logbuffers, plb, plb_next);
 653         mtx_unlock_spin(&po->po_mtx);
 654         if (wakeup)
 655                 wakeup_one(po);
 656 }
 657
 658 /*
 659  * Stop the helper kthread.
 660  */
 661
 662 static void
 663 pmclog_stop_kthread(struct pmc_owner *po)
 664 {
 665
 666         mtx_lock(&pmc_kthread_mtx);
 667         po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
 668         if (po->po_kthread != NULL) {
 669                 PROC_LOCK(po->po_kthread);
 670                 kern_psignal(po->po_kthread, SIGHUP);
 671                 PROC_UNLOCK(po->po_kthread);
 672         }
 673         wakeup_one(po);
 674         while (po->po_kthread)
 675                 msleep(po->po_kthread, &pmc_kthread_mtx, PPAUSE, "pmckstp", 0);
 676         mtx_unlock(&pmc_kthread_mtx);
 677 }
 678
 679 /*
 680  * Public functions
 681  */
 682
 683 /*
 684  * Configure a log file for pmc owner 'po'.
 685  *
 686  * Parameter 'logfd' is a file handle referencing an open file in the
 687  * owner process.  This file needs to have been opened for writing.
 688  */
 689
 690 int
 691 pmclog_configure_log(struct pmc_mdep *md, struct pmc_owner *po, int logfd)
 692 {
 693         struct proc *p;
 694         struct timespec ts;
 695         uint64_t tsc;
 696         int error;
 697
 698         sx_assert(&pmc_sx, SA_XLOCKED);
 699         PMCDBG2(LOG,CFG,1, "config po=%p logfd=%d", po, logfd);
 700
 701         p = po->po_owner;
 702
 703         /* return EBUSY if a log file was already present */
 704         if (po->po_flags & PMC_PO_OWNS_LOGFILE)
 705                 return (EBUSY);
 706
 707         KASSERT(po->po_file == NULL,
 708             ("[pmclog,%d] po=%p file (%p) already present", __LINE__, po,
 709                 po->po_file));
 710
 711         /* get a reference to the file state */
 712         error = fget_write(curthread, logfd, &cap_write_rights, &po->po_file);
 713         if (error)
 714                 goto error;
 715
 716         /* mark process as owning a log file */
 717         po->po_flags |= PMC_PO_OWNS_LOGFILE;
 718
 719         /* mark process as using HWPMCs */
 720         PROC_LOCK(p);
 721         p->p_flag |= P_HWPMC;
 722         PROC_UNLOCK(p);
 723         nanotime(&ts);
 724         tsc = pmc_rdtsc();
 725         /* create a log initialization entry */
 726         PMCLOG_RESERVE_WITH_ERROR(po, INITIALIZE,
 727             sizeof(struct pmclog_initialize));
 728         PMCLOG_EMIT32(PMC_VERSION);
 729         PMCLOG_EMIT32(md->pmd_cputype);
 730 #if defined(__i386__) || defined(__amd64__)
 731         PMCLOG_EMIT64(tsc_freq);
 732 #else
 733         /* other architectures will need to fill this in */
 734         PMCLOG_EMIT32(0);
 735         PMCLOG_EMIT32(0);
 736 #endif
 737         memcpy(_le, &ts, sizeof(ts));
 738         _le += sizeof(ts)/4;
 739         PMCLOG_EMITSTRING(pmc_cpuid, PMC_CPUID_LEN);
 740         PMCLOG_DESPATCH_SYNC(po);
 741
 742         return (0);
 743
 744  error:
 745         KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not "
 746             "stopped", __LINE__, po));
 747
 748         if (po->po_file)
 749                 (void) fdrop(po->po_file, curthread);
 750         po->po_file  = NULL;    /* clear file and error state */
 751         po->po_error = 0;
 752         po->po_flags &= ~PMC_PO_OWNS_LOGFILE;
 753
 754         return (error);
 755 }
 756
 757
 758 /*
 759  * De-configure a log file.  This will throw away any buffers queued
 760  * for this owner process.
 761  */
 762
 763 int
 764 pmclog_deconfigure_log(struct pmc_owner *po)
 765 {
 766         int error;
 767         struct pmclog_buffer *lb;
 768
 769         PMCDBG1(LOG,CFG,1, "de-config po=%p", po);
 770
 771         if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)
 772                 return (EINVAL);
 773
 774         KASSERT(po->po_sscount == 0,
 775             ("[pmclog,%d] po=%p still owning SS PMCs", __LINE__, po));
 776         KASSERT(po->po_file != NULL,
 777             ("[pmclog,%d] po=%p no log file", __LINE__, po));
 778
 779         /* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */
 780         pmclog_stop_kthread(po);
 781
 782         KASSERT(po->po_kthread == NULL,
 783             ("[pmclog,%d] po=%p kthread not stopped", __LINE__, po));
 784
 785         /* return all queued log buffers to the global pool */
 786         while ((lb = TAILQ_FIRST(&po->po_logbuffers)) != NULL) {
 787                 TAILQ_REMOVE(&po->po_logbuffers, lb, plb_next);
 788                 PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
 789                 pmc_plb_rele(lb);
 790         }
 791         for (int i = 0; i < mp_ncpus; i++) {
 792                 thread_lock(curthread);
 793                 sched_bind(curthread, i);
 794                 thread_unlock(curthread);
 795                 /* return the 'current' buffer to the global pool */
 796                 if ((lb = po->po_curbuf[curcpu]) != NULL) {
 797                         PMCLOG_RESET_BUFFER_DESCRIPTOR(lb);
 798                         pmc_plb_rele(lb);
 799                 }
 800         }
 801         thread_lock(curthread);
 802         sched_unbind(curthread);
 803         thread_unlock(curthread);
 804
 805         /* drop a reference to the fd */
 806         if (po->po_file != NULL) {
 807                 error = fdrop(po->po_file, curthread);
 808                 po->po_file = NULL;
 809         } else
 810                 error = 0;
 811         po->po_error = 0;
 812
 813         return (error);
 814 }
 815
 816 /*
 817  * Flush a process' log buffer.
 818  */
 819
 820 int
 821 pmclog_flush(struct pmc_owner *po, int force)
 822 {
 823         int error;
 824
 825         PMCDBG1(LOG,FLS,1, "po=%p", po);
 826
 827         /*
 828          * If there is a pending error recorded by the logger thread,
 829          * return that.
 830          */
 831         if (po->po_error)
 832                 return (po->po_error);
 833
 834         error = 0;
 835
 836         /*
 837          * Check that we do have an active log file.
 838          */
 839         mtx_lock(&pmc_kthread_mtx);
 840         if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) {
 841                 error = EINVAL;
 842                 goto error;
 843         }
 844
 845         pmclog_schedule_all(po);
 846  error:
 847         mtx_unlock(&pmc_kthread_mtx);
 848
 849         return (error);
 850 }
 851
 852 static void
 853 pmclog_schedule_one_cond(struct pmc_owner *po)
 854 {
 855         struct pmclog_buffer *plb;
 856         int cpu;
 857
 858         spinlock_enter();
 859         cpu = curcpu;
 860         /* tell hardclock not to run again */
 861         if (PMC_CPU_HAS_SAMPLES(cpu))
 862                 PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL);
 863
 864         plb = po->po_curbuf[cpu];
 865         if (plb && plb->plb_ptr != plb->plb_base)
 866                 pmclog_schedule_io(po, 1);
 867         spinlock_exit();
 868 }
 869
 870 static void
 871 pmclog_schedule_all(struct pmc_owner *po)
 872 {
 873         /*
 874          * Schedule the current buffer if any and not empty.
 875          */
 876         for (int i = 0; i < mp_ncpus; i++) {
 877                 thread_lock(curthread);
 878                 sched_bind(curthread, i);
 879                 thread_unlock(curthread);
 880                 pmclog_schedule_one_cond(po);
 881         }
 882         thread_lock(curthread);
 883         sched_unbind(curthread);
 884         thread_unlock(curthread);
 885 }
 886
 887 int
 888 pmclog_close(struct pmc_owner *po)
 889 {
 890
 891         PMCDBG1(LOG,CLO,1, "po=%p", po);
 892
 893         pmclog_process_closelog(po);
 894
 895         mtx_lock(&pmc_kthread_mtx);
 896         /*
 897          * Initiate shutdown: no new data queued,
 898          * thread will close file on last block.
 899          */
 900         po->po_flags |= PMC_PO_SHUTDOWN;
 901         /* give time for all to see */
 902         DELAY(50);
 903
 904         /*
 905          * Schedule the current buffer.
 906          */
 907         pmclog_schedule_all(po);
 908         wakeup_one(po);
 909
 910         mtx_unlock(&pmc_kthread_mtx);
 911
 912         return (0);
 913 }
 914
 915 void
 916 pmclog_process_callchain(struct pmc *pm, struct pmc_sample *ps)
 917 {
 918         int n, recordlen;
 919         uint32_t flags;
 920         struct pmc_owner *po;
 921
 922         PMCDBG3(LOG,SAM,1,"pm=%p pid=%d n=%d", pm, ps->ps_pid,
 923             ps->ps_nsamples);
 924
 925         recordlen = offsetof(struct pmclog_callchain, pl_pc) +
 926             ps->ps_nsamples * sizeof(uintfptr_t);
 927         po = pm->pm_owner;
 928         flags = PMC_CALLCHAIN_TO_CPUFLAGS(ps->ps_cpu,ps->ps_flags);
 929         PMCLOG_RESERVE_SAFE(po, CALLCHAIN, recordlen, ps->ps_tsc);
 930         PMCLOG_EMIT32(ps->ps_pid);
 931         PMCLOG_EMIT32(ps->ps_tid);
 932         PMCLOG_EMIT32(pm->pm_id);
 933         PMCLOG_EMIT32(flags);
 934         for (n = 0; n < ps->ps_nsamples; n++)
 935                 PMCLOG_EMITADDR(ps->ps_pc[n]);
 936         PMCLOG_DESPATCH_SAFE(po);
 937 }
 938
 939 void
 940 pmclog_process_closelog(struct pmc_owner *po)
 941 {
 942         PMCLOG_RESERVE(po,CLOSELOG,sizeof(struct pmclog_closelog));
 943         PMCLOG_DESPATCH_SYNC(po);
 944 }
 945
 946 void
 947 pmclog_process_dropnotify(struct pmc_owner *po)
 948 {
 949         PMCLOG_RESERVE(po,DROPNOTIFY,sizeof(struct pmclog_dropnotify));
 950         PMCLOG_DESPATCH(po);
 951 }
 952
 953 void
 954 pmclog_process_map_in(struct pmc_owner *po, pid_t pid, uintfptr_t start,
 955     const char *path)
 956 {
 957         int pathlen, recordlen;
 958
 959         KASSERT(path != NULL, ("[pmclog,%d] map-in, null path", __LINE__));
 960
 961         pathlen = strlen(path) + 1;     /* #bytes for path name */
 962         recordlen = offsetof(struct pmclog_map_in, pl_pathname) +
 963             pathlen;
 964
 965         PMCLOG_RESERVE(po, MAP_IN, recordlen);
 966         PMCLOG_EMIT32(pid);
 967         PMCLOG_EMIT32(0);
 968         PMCLOG_EMITADDR(start);
 969         PMCLOG_EMITSTRING(path,pathlen);
 970         PMCLOG_DESPATCH_SYNC(po);
 971 }
 972
 973 void
 974 pmclog_process_map_out(struct pmc_owner *po, pid_t pid, uintfptr_t start,
 975     uintfptr_t end)
 976 {
 977         KASSERT(start <= end, ("[pmclog,%d] start > end", __LINE__));
 978
 979         PMCLOG_RESERVE(po, MAP_OUT, sizeof(struct pmclog_map_out));
 980         PMCLOG_EMIT32(pid);
 981         PMCLOG_EMIT32(0);
 982         PMCLOG_EMITADDR(start);
 983         PMCLOG_EMITADDR(end);
 984         PMCLOG_DESPATCH(po);
 985 }
 986
 987 void
 988 pmclog_process_pmcallocate(struct pmc *pm)
 989 {
 990         struct pmc_owner *po;
 991         struct pmc_soft *ps;
 992
 993         po = pm->pm_owner;
 994
 995         PMCDBG1(LOG,ALL,1, "pm=%p", pm);
 996
 997         if (PMC_TO_CLASS(pm) == PMC_CLASS_SOFT) {
 998                 PMCLOG_RESERVE(po, PMCALLOCATEDYN,
 999                     sizeof(struct pmclog_pmcallocatedyn));
1000                 PMCLOG_EMIT32(pm->pm_id);
1001                 PMCLOG_EMIT32(pm->pm_event);
1002                 PMCLOG_EMIT32(pm->pm_flags);
1003                 PMCLOG_EMIT32(0);
1004                 PMCLOG_EMIT64(pm->pm_sc.pm_reloadcount);
1005                 ps = pmc_soft_ev_acquire(pm->pm_event);
1006                 if (ps != NULL)
1007                         PMCLOG_EMITSTRING(ps->ps_ev.pm_ev_name,PMC_NAME_MAX);
1008                 else
1009                         PMCLOG_EMITNULLSTRING(PMC_NAME_MAX);
1010                 pmc_soft_ev_release(ps);
1011                 PMCLOG_DESPATCH_SYNC(po);
1012         } else {
1013                 PMCLOG_RESERVE(po, PMCALLOCATE,
1014                     sizeof(struct pmclog_pmcallocate));
1015                 PMCLOG_EMIT32(pm->pm_id);
1016                 PMCLOG_EMIT32(pm->pm_event);
1017                 PMCLOG_EMIT32(pm->pm_flags);
1018                 PMCLOG_EMIT32(0);
1019                 PMCLOG_EMIT64(pm->pm_sc.pm_reloadcount);
1020                 PMCLOG_DESPATCH_SYNC(po);
1021         }
1022 }
1023
1024 void
1025 pmclog_process_pmcattach(struct pmc *pm, pid_t pid, char *path)
1026 {
1027         int pathlen, recordlen;
1028         struct pmc_owner *po;
1029
1030         PMCDBG2(LOG,ATT,1,"pm=%p pid=%d", pm, pid);
1031
1032         po = pm->pm_owner;
1033
1034         pathlen = strlen(path) + 1;     /* #bytes for the string */
1035         recordlen = offsetof(struct pmclog_pmcattach, pl_pathname) + pathlen;
1036
1037         PMCLOG_RESERVE(po, PMCATTACH, recordlen);
1038         PMCLOG_EMIT32(pm->pm_id);
1039         PMCLOG_EMIT32(pid);
1040         PMCLOG_EMITSTRING(path, pathlen);
1041         PMCLOG_DESPATCH_SYNC(po);
1042 }
1043
1044 void
1045 pmclog_process_pmcdetach(struct pmc *pm, pid_t pid)
1046 {
1047         struct pmc_owner *po;
1048
1049         PMCDBG2(LOG,ATT,1,"!pm=%p pid=%d", pm, pid);
1050
1051         po = pm->pm_owner;
1052
1053         PMCLOG_RESERVE(po, PMCDETACH, sizeof(struct pmclog_pmcdetach));
1054         PMCLOG_EMIT32(pm->pm_id);
1055         PMCLOG_EMIT32(pid);
1056         PMCLOG_DESPATCH_SYNC(po);
1057 }
1058
1059 void
1060 pmclog_process_proccreate(struct pmc_owner *po, struct proc *p, int sync)
1061 {
1062         if (sync) {
1063                 PMCLOG_RESERVE(po, PROC_CREATE, sizeof(struct pmclog_proccreate));
1064                 PMCLOG_EMIT32(p->p_pid);
1065                 PMCLOG_EMIT32(p->p_flag);
1066                 PMCLOG_EMITSTRING(p->p_comm, MAXCOMLEN+1);
1067                 PMCLOG_DESPATCH_SYNC(po);
1068         } else {
1069                 PMCLOG_RESERVE(po, PROC_CREATE, sizeof(struct pmclog_proccreate));
1070                 PMCLOG_EMIT32(p->p_pid);
1071                 PMCLOG_EMIT32(p->p_flag);
1072                 PMCLOG_EMITSTRING(p->p_comm, MAXCOMLEN+1);
1073                 PMCLOG_DESPATCH(po);
1074         }
1075 }
1076
1077 /*
1078  * Log a context switch event to the log file.
1079  */
1080
1081 void
1082 pmclog_process_proccsw(struct pmc *pm, struct pmc_process *pp, pmc_value_t v, struct thread *td)
1083 {
1084         struct pmc_owner *po;
1085
1086         KASSERT(pm->pm_flags & PMC_F_LOG_PROCCSW,
1087             ("[pmclog,%d] log-process-csw called gratuitously", __LINE__));
1088
1089         PMCDBG3(LOG,SWO,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
1090             v);
1091
1092         po = pm->pm_owner;
1093
1094         PMCLOG_RESERVE_SAFE(po, PROCCSW, sizeof(struct pmclog_proccsw), pmc_rdtsc());
1095         PMCLOG_EMIT64(v);
1096         PMCLOG_EMIT32(pm->pm_id);
1097         PMCLOG_EMIT32(pp->pp_proc->p_pid);
1098         PMCLOG_EMIT32(td->td_tid);
1099         PMCLOG_EMIT32(0);
1100         PMCLOG_DESPATCH_SCHED_LOCK(po);
1101 }
1102
1103 void
1104 pmclog_process_procexec(struct pmc_owner *po, pmc_id_t pmid, pid_t pid,
1105     uintfptr_t startaddr, char *path)
1106 {
1107         int pathlen, recordlen;
1108
1109         PMCDBG3(LOG,EXC,1,"po=%p pid=%d path=\"%s\"", po, pid, path);
1110
1111         pathlen   = strlen(path) + 1;   /* #bytes for the path */
1112         recordlen = offsetof(struct pmclog_procexec, pl_pathname) + pathlen;
1113         PMCLOG_RESERVE(po, PROCEXEC, recordlen);
1114         PMCLOG_EMIT32(pid);
1115         PMCLOG_EMIT32(pmid);
1116         PMCLOG_EMITADDR(startaddr);
1117         PMCLOG_EMITSTRING(path,pathlen);
1118         PMCLOG_DESPATCH_SYNC(po);
1119 }
1120
1121 /*
1122  * Log a process exit event (and accumulated pmc value) to the log file.
1123  */
1124
1125 void
1126 pmclog_process_procexit(struct pmc *pm, struct pmc_process *pp)
1127 {
1128         int ri;
1129         struct pmc_owner *po;
1130
1131         ri = PMC_TO_ROWINDEX(pm);
1132         PMCDBG3(LOG,EXT,1,"pm=%p pid=%d v=%jx", pm, pp->pp_proc->p_pid,
1133             pp->pp_pmcs[ri].pp_pmcval);
1134
1135         po = pm->pm_owner;
1136
1137         PMCLOG_RESERVE(po, PROCEXIT, sizeof(struct pmclog_procexit));
1138         PMCLOG_EMIT32(pm->pm_id);
1139         PMCLOG_EMIT32(pp->pp_proc->p_pid);
1140         PMCLOG_EMIT64(pp->pp_pmcs[ri].pp_pmcval);
1141         PMCLOG_DESPATCH(po);
1142 }
1143
1144 /*
1145  * Log a fork event.
1146  */
1147
1148 void
1149 pmclog_process_procfork(struct pmc_owner *po, pid_t oldpid, pid_t newpid)
1150 {
1151         PMCLOG_RESERVE(po, PROCFORK, sizeof(struct pmclog_procfork));
1152         PMCLOG_EMIT32(oldpid);
1153         PMCLOG_EMIT32(newpid);
1154         PMCLOG_DESPATCH(po);
1155 }
1156
1157 /*
1158  * Log a process exit event of the form suitable for system-wide PMCs.
1159  */
1160
1161 void
1162 pmclog_process_sysexit(struct pmc_owner *po, pid_t pid)
1163 {
1164         PMCLOG_RESERVE(po, SYSEXIT, sizeof(struct pmclog_sysexit));
1165         PMCLOG_EMIT32(pid);
1166         PMCLOG_DESPATCH(po);
1167 }
1168
1169 void
1170 pmclog_process_threadcreate(struct pmc_owner *po, struct thread *td, int sync)
1171 {
1172         struct proc *p;
1173
1174         p = td->td_proc;
1175         if (sync) {
1176                 PMCLOG_RESERVE(po, THR_CREATE, sizeof(struct pmclog_threadcreate));
1177                 PMCLOG_EMIT32(td->td_tid);
1178                 PMCLOG_EMIT32(p->p_pid);
1179                 PMCLOG_EMIT32(p->p_flag);
1180                 PMCLOG_EMIT32(0);
1181                 PMCLOG_EMITSTRING(td->td_name, MAXCOMLEN+1);
1182                 PMCLOG_DESPATCH_SYNC(po);
1183         } else {
1184                 PMCLOG_RESERVE(po, THR_CREATE, sizeof(struct pmclog_threadcreate));
1185                 PMCLOG_EMIT32(td->td_tid);
1186                 PMCLOG_EMIT32(p->p_pid);
1187                 PMCLOG_EMIT32(p->p_flag);
1188                 PMCLOG_EMIT32(0);
1189                 PMCLOG_EMITSTRING(td->td_name, MAXCOMLEN+1);
1190                 PMCLOG_DESPATCH(po);
1191         }
1192 }
1193
1194 void
1195 pmclog_process_threadexit(struct pmc_owner *po, struct thread *td)
1196 {
1197
1198         PMCLOG_RESERVE(po, THR_EXIT, sizeof(struct pmclog_threadexit));
1199         PMCLOG_EMIT32(td->td_tid);
1200         PMCLOG_DESPATCH(po);
1201 }
1202
1203 /*
1204  * Write a user log entry.
1205  */
1206
1207 int
1208 pmclog_process_userlog(struct pmc_owner *po, struct pmc_op_writelog *wl)
1209 {
1210         int error;
1211
1212         PMCDBG2(LOG,WRI,1, "writelog po=%p ud=0x%x", po, wl->pm_userdata);
1213
1214         error = 0;
1215
1216         PMCLOG_RESERVE_WITH_ERROR(po, USERDATA,
1217             sizeof(struct pmclog_userdata));
1218         PMCLOG_EMIT32(wl->pm_userdata);
1219         PMCLOG_DESPATCH(po);
1220
1221  error:
1222         return (error);
1223 }
1224
1225 /*
1226  * Initialization.
1227  *
1228  * Create a pool of log buffers and initialize mutexes.
1229  */
1230
1231 void
1232 pmclog_initialize()
1233 {
1234         int domain;
1235         struct pmclog_buffer *plb;
1236
1237         if (pmclog_buffer_size <= 0 || pmclog_buffer_size > 16*1024) {
1238                 (void) printf("hwpmc: tunable logbuffersize=%d must be "
1239                                           "greater than zero and less than or equal to 16MB.\n",
1240                                           pmclog_buffer_size);
1241                 pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1242         }
1243
1244         if (pmc_nlogbuffers_pcpu <= 0) {
1245                 (void) printf("hwpmc: tunable nlogbuffers=%d must be greater "
1246                                           "than zero.\n", pmc_nlogbuffers_pcpu);
1247                 pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
1248         }
1249         if (pmc_nlogbuffers_pcpu*pmclog_buffer_size > 32*1024) {
1250                 (void) printf("hwpmc: memory allocated pcpu must be less than 32MB (is %dK).\n",
1251                                           pmc_nlogbuffers_pcpu*pmclog_buffer_size);
1252                 pmc_nlogbuffers_pcpu = PMC_NLOGBUFFERS_PCPU;
1253                 pmclog_buffer_size = PMC_LOG_BUFFER_SIZE;
1254         }
1255         for (domain = 0; domain < vm_ndomains; domain++) {
1256                 int ncpus = pmc_dom_hdrs[domain]->pdbh_ncpus;
1257                 int total = ncpus*pmc_nlogbuffers_pcpu;
1258
1259                 plb = malloc_domain(sizeof(struct pmclog_buffer)*total, M_PMC, domain, M_WAITOK|M_ZERO);
1260                 pmc_dom_hdrs[domain]->pdbh_plbs = plb;
1261                 for (int i = 0; i < total; i++, plb++) {
1262                         void *buf;
1263
1264                         buf = malloc_domain(1024 * pmclog_buffer_size, M_PMC, domain,
1265                                                                 M_WAITOK|M_ZERO);
1266                         PMCLOG_INIT_BUFFER_DESCRIPTOR(plb, buf, domain);
1267                         pmc_plb_rele_unlocked(plb);
1268                 }
1269         }
1270         mtx_init(&pmc_kthread_mtx, "pmc-kthread", "pmc-sleep", MTX_DEF);
1271 }
1272
1273 /*
1274  * Shutdown logging.
1275  *
1276  * Destroy mutexes and release memory back the to free pool.
1277  */
1278
1279 void
1280 pmclog_shutdown()
1281 {
1282         struct pmclog_buffer *plb;
1283         int domain;
1284
1285         mtx_destroy(&pmc_kthread_mtx);
1286
1287         for (domain = 0; domain < vm_ndomains; domain++) {
1288                 while ((plb = TAILQ_FIRST(&pmc_dom_hdrs[domain]->pdbh_head)) != NULL) {
1289                         TAILQ_REMOVE(&pmc_dom_hdrs[domain]->pdbh_head, plb, plb_next);
1290                         free(plb->plb_base, M_PMC);
1291                 }
1292                 free(pmc_dom_hdrs[domain]->pdbh_plbs, M_PMC);
1293         }
1294 }