BSD 4.4 Lite Kernel Sources

1 files changed, 256 insertions, 0 deletions

diff --git a/sys/kern/subr_prof.c b/sys/kern/subr_prof.c
new file mode 100644
index 0000000..4fb81d8
--- /dev/null
+++ b/sys/kern/subr_prof.c
@@ -0,0 +1,256 @@
+/*-
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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/user.h>
+#include <machine/cpu.h>
+
+#ifdef GPROF
+#include <sys/malloc.h>
+#include <sys/gmon.h>
+
+/*
+ * Froms is actually a bunch of unsigned shorts indexing tos
+ */
+struct gmonparam _gmonparam = { GMON_PROF_OFF };
+
+extern char etext[];
+
+kmstartup()
+{
+	char *cp;
+	struct gmonparam *p = &_gmonparam;
+	/*
+	 * 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=%d [%x..%x]\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);
+	cp = (char *)malloc(p->kcountsize + p->fromssize + p->tossize,
+	    M_GPROF, M_NOWAIT);
+	if (cp == 0) {
+		printf("No memory for profiling.\n");
+		return;
+	}
+	bzero(cp, p->kcountsize + p->tossize + p->fromssize);
+	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.
+ */
+sysctl_doprof(name, namelen, oldp, oldlenp, newp, newlen, p)
+	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.
+ */
+struct profil_args {
+	caddr_t	samples;
+	u_int	size;
+	u_int	offset;
+	u_int	scale;
+};
+/* ARGSUSED */
+profil(p, uap, retval)
+	struct proc *p;
+	register struct profil_args *uap;
+	int *retval;
+{
+	register struct uprof *upp;
+	int s;
+
+	if (uap->scale > (1 << 16))
+		return (EINVAL);
+	if (uap->scale == 0) {
+		stopprofclock(p);
+		return (0);
+	}
+	upp = &p->p_stats->p_prof;
+
+	/* Block profile interrupts while changing state. */
+	s = splstatclock();
+	upp->pr_off = uap->offset;
+	upp->pr_scale = uap->scale;
+	upp->pr_base = uap->samples;
+	upp->pr_size = 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.  We try to update the user profiling buffers
+ * cheaply with fuswintr() and suswintr().  If that fails, we revert to
+ * an AST that will vector us to trap() with a context in which copyin
+ * and copyout will work.  Trap will then call addupc_task().
+ *
+ * Note that we may (rarely) not get around to the AST soon enough, and
+ * lose profile ticks when the next tick overwrites this one, but in this
+ * case the system is overloaded and the profile is probably already
+ * inaccurate.
+ */
+void
+addupc_intr(p, pc, ticks)
+	register struct proc *p;
+	register u_long pc;
+	u_int ticks;
+{
+	register struct uprof *prof;
+	register caddr_t addr;
+	register u_int i;
+	register int v;
+
+	if (ticks == 0)
+		return;
+	prof = &p->p_stats->p_prof;
+	if (pc < prof->pr_off ||
+	    (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size)
+		return;			/* out of range; ignore */
+
+	addr = prof->pr_base + i;
+	if ((v = fuswintr(addr)) == -1 || suswintr(addr, v + ticks) == -1) {
+		prof->pr_addr = pc;
+		prof->pr_ticks = ticks;
+		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(p, pc, ticks)
+	register struct proc *p;
+	register u_long pc;
+	u_int ticks;
+{
+	register struct uprof *prof;
+	register caddr_t addr;
+	register u_int i;
+	u_short v;
+
+	/* Testing P_PROFIL may be unnecessary, but is certainly safe. */
+	if ((p->p_flag & P_PROFIL) == 0 || ticks == 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 += ticks;
+		if (copyout((caddr_t)&v, addr, sizeof(v)) == 0)
+			return;
+	}
+	stopprofclock(p);
+}