/* $OpenBSD: subr_prof.c,v 1.19 2010/07/09 20:30:48 deraadt Exp $ */ /* $NetBSD: subr_prof.c,v 1.12 1996/04/22 01:38:50 christos Exp $ */ /*- * Copyright (c) 1982, 1986, 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. * * @(#)subr_prof.c 8.3 (Berkeley) 9/23/93 */ #include <sys/param.h> #include <sys/systm.h> #include <sys/kernel.h> #include <sys/proc.h> #include <sys/resourcevar.h> #include <sys/mount.h> #include <sys/sysctl.h> #include <sys/syscallargs.h> #include <machine/cpu.h> #ifdef GPROF #include <sys/malloc.h> #include <sys/gmon.h> #include <uvm/uvm_extern.h> /* * Froms is actually a bunch of unsigned shorts indexing tos */ struct gmonparam _gmonparam = { GMON_PROF_OFF }; extern char etext[]; void kmstartup(void) { char *cp; struct gmonparam *p = &_gmonparam; int size; /* * Round lowpc and highpc to multiples of the density we're using * so the rest of the scaling (here and in gprof) stays in ints. */ p->lowpc = ROUNDDOWN(KERNBASE, HISTFRACTION * sizeof(HISTCOUNTER)); p->highpc = ROUNDUP((u_long)etext, HISTFRACTION * sizeof(HISTCOUNTER)); p->textsize = p->highpc - p->lowpc; printf("Profiling kernel, textsize=%ld [%lx..%lx]\n", p->textsize, p->lowpc, p->highpc); p->kcountsize = p->textsize / HISTFRACTION; p->hashfraction = HASHFRACTION; p->fromssize = p->textsize / HASHFRACTION; p->tolimit = p->textsize * ARCDENSITY / 100; if (p->tolimit < MINARCS) p->tolimit = MINARCS; else if (p->tolimit > MAXARCS) p->tolimit = MAXARCS; p->tossize = p->tolimit * sizeof(struct tostruct); size = p->kcountsize + p->fromssize + p->tossize; cp = (char *)uvm_km_zalloc(kernel_map, round_page(size)); if (cp == 0) { printf("No memory for profiling.\n"); return; } p->tos = (struct tostruct *)cp; cp += p->tossize; p->kcount = (u_short *)cp; cp += p->kcountsize; p->froms = (u_short *)cp; } /* * Return kernel profiling information. */ int sysctl_doprof(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp, size_t newlen) { struct gmonparam *gp = &_gmonparam; int error; /* all sysctl names at this level are terminal */ if (namelen != 1) return (ENOTDIR); /* overloaded */ switch (name[0]) { case GPROF_STATE: error = sysctl_int(oldp, oldlenp, newp, newlen, &gp->state); if (error) return (error); if (gp->state == GMON_PROF_OFF) stopprofclock(&proc0); else startprofclock(&proc0); return (0); case GPROF_COUNT: return (sysctl_struct(oldp, oldlenp, newp, newlen, gp->kcount, gp->kcountsize)); case GPROF_FROMS: return (sysctl_struct(oldp, oldlenp, newp, newlen, gp->froms, gp->fromssize)); case GPROF_TOS: return (sysctl_struct(oldp, oldlenp, newp, newlen, gp->tos, gp->tossize)); case GPROF_GMONPARAM: return (sysctl_rdstruct(oldp, oldlenp, newp, gp, sizeof *gp)); default: return (EOPNOTSUPP); } /* NOTREACHED */ } #endif /* GPROF */ /* * Profiling system call. * * The scale factor is a fixed point number with 16 bits of fraction, so that * 1.0 is represented as 0x10000. A scale factor of 0 turns off profiling. */ /* ARGSUSED */ int sys_profil(struct proc *p, void *v, register_t *retval) { struct sys_profil_args /* { syscallarg(caddr_t) samples; syscallarg(size_t) size; syscallarg(u_long) offset; syscallarg(u_int) scale; } */ *uap = v; struct uprof *upp; int s; if (SCARG(uap, scale) > (1 << 16)) return (EINVAL); if (SCARG(uap, scale) == 0) { stopprofclock(p); return (0); } upp = &p->p_stats->p_prof; /* Block profile interrupts while changing state. */ s = splstatclock(); upp->pr_off = SCARG(uap, offset); upp->pr_scale = SCARG(uap, scale); upp->pr_base = (caddr_t)SCARG(uap, samples); upp->pr_size = SCARG(uap, size); startprofclock(p); splx(s); return (0); } /* * Scale is a fixed-point number with the binary point 16 bits * into the value, and is <= 1.0. pc is at most 32 bits, so the * intermediate result is at most 48 bits. */ #define PC_TO_INDEX(pc, prof) \ ((int)(((u_quad_t)((pc) - (prof)->pr_off) * \ (u_quad_t)((prof)->pr_scale)) >> 16) & ~1) /* * Collect user-level profiling statistics; called on a profiling tick, * when a process is running in user-mode. This routine may be called * from an interrupt context. Schedule an AST that will vector us to * trap() with a context in which copyin and copyout will work. * Trap will then call addupc_task(). */ void addupc_intr(struct proc *p, u_long pc) { struct uprof *prof; prof = &p->p_stats->p_prof; if (pc < prof->pr_off || PC_TO_INDEX(pc, prof) >= prof->pr_size) return; /* out of range; ignore */ prof->pr_addr = pc; prof->pr_ticks++; atomic_setbits_int(&p->p_flag, P_OWEUPC); need_proftick(p); } /* * Much like before, but we can afford to take faults here. If the * update fails, we simply turn off profiling. */ void addupc_task(struct proc *p, u_long pc, u_int nticks) { struct uprof *prof; caddr_t addr; u_int i; u_short v; /* Testing P_PROFIL may be unnecessary, but is certainly safe. */ if ((p->p_flag & P_PROFIL) == 0 || nticks == 0) return; prof = &p->p_stats->p_prof; if (pc < prof->pr_off || (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) return; addr = prof->pr_base + i; if (copyin(addr, (caddr_t)&v, sizeof(v)) == 0) { v += nticks; if (copyout((caddr_t)&v, addr, sizeof(v)) == 0) return; } stopprofclock(p); }