/* $NetBSD: mcount.c,v 1.18 2024/02/23 13:32:28 christos Exp $ */ /* * Copyright (c) 2003, 2004 Wasabi Systems, Inc. * All rights reserved. * * Written by Nathan J. Williams for Wasabi Systems, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the NetBSD Project by * Wasabi Systems, Inc. * 4. The name of Wasabi Systems, Inc. may not be used to endorse * or promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /*- * Copyright (c) 1983, 1992, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifdef _KERNEL_OPT #include "opt_multiprocessor.h" #endif /* If building a standalone libkern, don't include mcount. */ #if (!defined(_KERNEL) || defined(GPROF)) && !defined(_STANDALONE) #include <sys/cdefs.h> #if !defined(lint) && !defined(_KERNEL) && defined(LIBC_SCCS) #if 0 static char sccsid[] = "@(#)mcount.c 8.1 (Berkeley) 6/4/93"; #else __RCSID("$NetBSD: mcount.c,v 1.18 2024/02/23 13:32:28 christos Exp $"); #endif #endif #include <sys/param.h> #include <sys/gmon.h> #include <sys/lock.h> #include <sys/proc.h> #ifndef _KERNEL #include "reentrant.h" #endif #if defined(_REENTRANT) && !defined(_RUMPKERNEL) extern thread_key_t _gmonkey; extern struct gmonparam _gmondummy; struct gmonparam *_m_gmon_alloc(void); #endif _MCOUNT_DECL(u_long, u_long) #ifdef _KERNEL __attribute__((__no_instrument_function__)) #endif __used; /* XXX: make these interfaces */ #ifdef _RUMPKERNEL #undef MCOUNT_ENTER #define MCOUNT_ENTER #undef MCOUNT_EXIT #define MCOUNT_EXIT #undef MCOUNT #define MCOUNT #endif /* * mcount is called on entry to each function compiled with the profiling * switch set. _mcount(), which is declared in a machine-dependent way * with _MCOUNT_DECL, does the actual work and is either inlined into a * C routine or called by an assembly stub. In any case, this magic is * taken care of by the MCOUNT definition in <machine/profile.h>. * * _mcount updates data structures that represent traversals of the * program's call graph edges. frompc and selfpc are the return * address and function address that represents the given call graph edge. * * Note: the original BSD code used the same variable (frompcindex) for * both frompcindex and frompc. Any reasonable, modern compiler will * perform this optimization. */ /* _mcount; may be static, inline, etc */ /*LINTED unused*/ _MCOUNT_DECL(u_long frompc, u_long selfpc) { u_short *frompcindex; struct tostruct *top, *prevtop; struct gmonparam *p; long toindex; #if defined(_KERNEL) && !defined(_RUMPKERNEL) int s; #endif #if defined(_REENTRANT) && !defined(_KERNEL) && !defined(_RUMPKERNEL) if (__isthreaded) { /* prevent re-entry via thr_getspecific */ if (_gmonparam.state != GMON_PROF_ON) return; _gmonparam.state = GMON_PROF_BUSY; p = thr_getspecific(_gmonkey); if (p == NULL) { /* Prevent recursive calls while allocating */ thr_setspecific(_gmonkey, &_gmondummy); p = _m_gmon_alloc(); } _gmonparam.state = GMON_PROF_ON; } else #endif p = &_gmonparam; /* * check that we are profiling * and that we aren't recursively invoked. */ if (p->state != GMON_PROF_ON) return; #if defined(_KERNEL) && !defined(_RUMPKERNEL) MCOUNT_ENTER; #ifdef MULTIPROCESSOR p = curcpu()->ci_gmon; if (p == NULL || p->state != GMON_PROF_ON) { MCOUNT_EXIT; return; } #endif #endif p->state = GMON_PROF_BUSY; /* * check that frompcindex is a reasonable pc value. * for example: signal catchers get called from the stack, * not from text space. too bad. */ frompc -= p->lowpc; if (frompc > p->textsize) goto done; #if (HASHFRACTION & (HASHFRACTION - 1)) == 0 if (p->hashfraction == HASHFRACTION) frompcindex = &p->froms[ (size_t)(frompc / (HASHFRACTION * sizeof(*p->froms)))]; else #endif frompcindex = &p->froms[ (size_t)(frompc / (p->hashfraction * sizeof(*p->froms)))]; toindex = *frompcindex; if (toindex == 0) { /* * first time traversing this arc */ toindex = ++p->tos[0].link; if (toindex >= p->tolimit) /* halt further profiling */ goto overflow; *frompcindex = (u_short)toindex; top = &p->tos[(size_t)toindex]; top->selfpc = selfpc; top->count = 1; top->link = 0; goto done; } top = &p->tos[(size_t)toindex]; if (top->selfpc == selfpc) { /* * arc at front of chain; usual case. */ top->count++; goto done; } /* * have to go looking down chain for it. * top points to what we are looking at, * prevtop points to previous top. * we know it is not at the head of the chain. */ for (; /* goto done */; ) { if (top->link == 0) { /* * top is end of the chain and none of the chain * had top->selfpc == selfpc. * so we allocate a new tostruct * and link it to the head of the chain. */ toindex = ++p->tos[0].link; if (toindex >= p->tolimit) goto overflow; top = &p->tos[(size_t)toindex]; top->selfpc = selfpc; top->count = 1; top->link = *frompcindex; *frompcindex = (u_short)toindex; goto done; } /* * otherwise, check the next arc on the chain. */ prevtop = top; top = &p->tos[top->link]; if (top->selfpc == selfpc) { /* * there it is. * increment its count * move it to the head of the chain. */ top->count++; toindex = prevtop->link; prevtop->link = top->link; top->link = *frompcindex; *frompcindex = (u_short)toindex; goto done; } } done: p->state = GMON_PROF_ON; #if defined(_KERNEL) && !defined(_RUMPKERNEL) MCOUNT_EXIT; #endif return; overflow: p->state = GMON_PROF_ERROR; #if defined(_KERNEL) && !defined(_RUMPKERNEL) MCOUNT_EXIT; #endif return; } #ifdef MCOUNT /* * Actual definition of mcount function. Defined in <machine/profile.h>, * which is included by <sys/gmon.h>. */ MCOUNT #endif #if defined(_KERNEL) && !defined(_RUMPKERNEL) && defined(MULTIPROCESSOR) void _gmonparam_merge(struct gmonparam *, struct gmonparam *); void _gmonparam_merge(struct gmonparam *p, struct gmonparam *q) { u_long fromindex; u_short *frompcindex, qtoindex, toindex; u_long selfpc; u_long endfrom; long count; struct tostruct *top; int i; count = q->kcountsize / sizeof(*q->kcount); for (i = 0; i < count; i++) p->kcount[i] += q->kcount[i]; endfrom = (q->fromssize / sizeof(*q->froms)); for (fromindex = 0; fromindex < endfrom; fromindex++) { if (q->froms[fromindex] == 0) continue; for (qtoindex = q->froms[fromindex]; qtoindex != 0; qtoindex = q->tos[qtoindex].link) { selfpc = q->tos[qtoindex].selfpc; count = q->tos[qtoindex].count; /* cribbed from mcount */ frompcindex = &p->froms[fromindex]; toindex = *frompcindex; if (toindex == 0) { /* * first time traversing this arc */ toindex = ++p->tos[0].link; if (toindex >= p->tolimit) /* halt further profiling */ goto overflow; *frompcindex = (u_short)toindex; top = &p->tos[(size_t)toindex]; top->selfpc = selfpc; top->count = count; top->link = 0; goto done; } top = &p->tos[(size_t)toindex]; if (top->selfpc == selfpc) { /* * arc at front of chain; usual case. */ top->count+= count; goto done; } /* * have to go looking down chain for it. * top points to what we are looking at, * we know it is not at the head of the chain. */ for (; /* goto done */; ) { if (top->link == 0) { /* * top is end of the chain and * none of the chain had * top->selfpc == selfpc. so * we allocate a new tostruct * and link it to the head of * the chain. */ toindex = ++p->tos[0].link; if (toindex >= p->tolimit) goto overflow; top = &p->tos[(size_t)toindex]; top->selfpc = selfpc; top->count = count; top->link = *frompcindex; *frompcindex = (u_short)toindex; goto done; } /* * otherwise, check the next arc on the chain. */ top = &p->tos[top->link]; if (top->selfpc == selfpc) { /* * there it is. * add to its count. */ top->count += count; goto done; } } done: ; } } overflow: ; } #endif #endif /* (!_KERNEL || GPROF) && !_STANDALONE */
