Bring a working snapshot of hwpmc(4), its associated libraries, userland utilities

and documentation into -CURRENT.

Bump FreeBSD_version.

Reviewed by:	alc, jhb (kernel changes)

7 files changed, 1568 insertions, 0 deletions

diff --git a/usr.sbin/Makefile b/usr.sbin/Makefile
index e8b528b..071435e 100644
--- a/usr.sbin/Makefile
+++ b/usr.sbin/Makefile
@@ -112,6 +112,8 @@ SUBDIR=	ac \
 	${_pcvt} \
 	periodic \
 	pkg_install \
+	pmccontrol \
+	pmcstat \
 	${_pnpinfo} \
 	powerd \
 	ppp \
diff --git a/usr.sbin/pmccontrol/Makefile b/usr.sbin/pmccontrol/Makefile
new file mode 100644
index 0000000..851b1c7
--- /dev/null
+++ b/usr.sbin/pmccontrol/Makefile
@@ -0,0 +1,17 @@
+#
+# $FreeBSD$
+#
+
+PROG=	pmccontrol
+MAN=	pmccontrol.8
+
+DPADD=	${LIBPMC}
+LDADD=	-lpmc
+
+WARNS=	6
+
+CFLAGS+=	-I${.CURDIR}/../../sys -I${.CURDIR}/../../lib/libpmc
+
+SRCS=	pmccontrol.c
+
+.include <bsd.prog.mk>
diff --git a/usr.sbin/pmccontrol/pmccontrol.8 b/usr.sbin/pmccontrol/pmccontrol.8
new file mode 100644
index 0000000..61b61aa
--- /dev/null
+++ b/usr.sbin/pmccontrol/pmccontrol.8
@@ -0,0 +1,132 @@
+.\" Copyright (c) 2003 Joseph Koshy.  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.
+.\"
+.\" This software is provided by Joseph Koshy ``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 Joseph Koshy 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd Dec 15, 2003
+.Os
+.Dt PMCCONTROL 8
+.Sh NAME
+.Nm pmccontrol
+.Nd control hardware performance monitoring counters
+.Sh SYNOPSIS
+.Nm
+.Oo
+.Op Fl c Ar cpu
+.Op Fl e Ar pmc
+.Op Fl d Ar pmc
+.Oc Ns ...
+.Nm
+.Op Fl lL
+.Nm
+.Op Fl s
+.Sh DESCRIPTION
+The
+.Nm
+utility controls the operation of the system's hardware performance
+monitoring counters.
+.Sh OPTIONS
+The
+.Nm
+utility processes options in command line order, so later options modify
+the effect of earlier ones.
+The following options are available:
+.Bl -tag -width indent
+.It Fl c Ar cpu
+Subsequent enable and disable options affect the CPU
+denoted by
+.Ar cpu .
+The argument
+.Ar cpu
+is either a number denoting a CPU number in the system, or the string
+.Dq Li \&* ,
+denoting all CPUs in the system.
+.It Fl d Ar pmc
+Disable PMC number
+.Ar pmc
+on the CPU specified by
+.Fl c ,
+preventing it from being used till subsequently re-enabled.
+The argument
+.Ar pmc
+is either a number denoting a specified PMC, or the string
+.Dq Li \&*
+denoting all the PMCs on the specified CPU.
+.Pp
+Only idle PMCs may be disabled.
+.\" XXX this probably needs to be fixed.
+.It Fl e Ar pmc
+Enable PMC number
+.Ar pmc ,
+on the CPU specified by
+.Fl c ,
+allowing it to be used in the future.
+The argument
+.Ar pmc
+is either a number denoting a specified PMC, or the string
+.Dq Li \&*
+denoting all the PMCs on the specified CPU.
+If PMC
+.Ar pmc
+is already enabled, this option has no effect.
+.It Fl l
+List available hardware performance counters and their current
+disposition.
+.It Fl L
+List available hardware performance counter classes and their
+supported event names.
+.It Fl s
+Print driver statistics maintained by
+.Xr hwpmc 4 .
+.El
+.Sh EXAMPLES
+To disable all PMCs on all CPUs, use the command:
+.Dl pmccontrol -d\&*
+.Pp
+To enable all PMCs on all CPUs, use:
+.Dl pmccontrol -e\&*
+.Pp
+To disable PMCs 0 and 1 on CPU 2, use:
+.Dl pmccontrol -c2 -d0 -d1
+.Pp
+To disable PMC 0 of CPU 0 only, and enable all other PMCS on all other
+CPUs, use:
+.Dl pmccontrol -c\&* -e\&* -c0 -d0
+.Sh DIAGNOSTICS
+.Ex -std pmccontrol
+.Sh HISTORY
+The
+.Nm
+utility is proposed to be integrated into
+.Fx
+sometime after
+.Fx 5.2 .
+.Nm
+.Bt
+.Sh AUTHORS
+.An Joseph Koshy Aq jkoshy@FreeBSD.org
+.Sh SEE ALSO
+.Xr pmc 3 ,
+.Xr hwpmc 4 ,
+.Xr pmcstat 8 ,
+.Xr sysctl 8
diff --git a/usr.sbin/pmccontrol/pmccontrol.c b/usr.sbin/pmccontrol/pmccontrol.c
new file mode 100644
index 0000000..a1ed2d5
--- /dev/null
+++ b/usr.sbin/pmccontrol/pmccontrol.c
@@ -0,0 +1,476 @@
+/*-
+ * Copyright (c) 2003,2004 Joseph Koshy
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/queue.h>
+#include <sys/sysctl.h>
+
+#include <assert.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <pmc.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <unistd.h>
+
+/* Compile time defaults */
+
+#define	PMCC_PRINT_USAGE	0
+#define	PMCC_PRINT_EVENTS	1
+#define	PMCC_LIST_STATE 	2
+#define	PMCC_ENABLE_DISABLE	3
+#define	PMCC_SHOW_STATISTICS	4
+
+#define	PMCC_CPU_ALL		-1
+#define	PMCC_CPU_WILDCARD	'*'
+
+#define	PMCC_PMC_ALL		-1
+#define	PMCC_PMC_WILDCARD	'*'
+
+#define	PMCC_OP_IGNORE		0
+#define	PMCC_OP_DISABLE		1
+#define	PMCC_OP_ENABLE		2
+
+#define	PMCC_PROGRAM_NAME	"pmccontrol"
+
+STAILQ_HEAD(pmcc_op_list, pmcc_op) head = STAILQ_HEAD_INITIALIZER(head);
+
+struct pmcc_op {
+	char	op_cpu;
+	char	op_pmc;
+	char	op_op;
+	STAILQ_ENTRY(pmcc_op) op_next;
+};
+
+/* Function Prototypes */
+#if	DEBUG
+static void	pmcc_init_debug(void);
+#endif
+
+static int	pmcc_do_list_state(void);
+static int	pmcc_do_enable_disable(struct pmcc_op_list *);
+static int	pmcc_do_list_events(void);
+
+/* Globals */
+
+static char usage_message[] =
+	"Usage:\n"
+	"       " PMCC_PROGRAM_NAME " -l\n"
+	"       " PMCC_PROGRAM_NAME " -s\n"
+	"       " PMCC_PROGRAM_NAME " [-e pmc | -d pmc | -c cpu] ...";
+
+#if DEBUG
+FILE *debug_stream = NULL;
+#endif
+
+#if DEBUG
+#define DEBUG_MSG(...)					                \
+	(void) fprintf(debug_stream, "[pmccontrol] " __VA_ARGS__);
+#else
+#define DEBUG_MSG(m)		/*  */
+#endif /* !DEBUG */
+
+int pmc_syscall = -1;
+
+#define PMC_CALL(cmd, params)						\
+if ((error = syscall(pmc_syscall, PMC_OP_##cmd, (params))) != 0)	\
+{									\
+	DEBUG_MSG("ERROR: syscall [" #cmd "]");				\
+	exit(EX_OSERR);							\
+}
+
+#if DEBUG
+/* log debug messages to a separate file */
+static void
+pmcc_init_debug(void)
+{
+	char *fn;
+
+	fn = getenv("PMCCONTROL_DEBUG");
+	if (fn != NULL)
+	{
+		debug_stream = fopen(fn, "w");
+		if (debug_stream == NULL)
+			debug_stream = stderr;
+	} else
+		debug_stream = stderr;
+}
+#endif
+
+static int
+pmcc_do_enable_disable(struct pmcc_op_list *op_list)
+{
+	unsigned char op;
+	int c, error, i, j, ncpu, npmc, t;
+	int cpu, pmc;
+	struct pmcc_op *np;
+	unsigned char *map;
+
+	if ((ncpu = pmc_ncpu()) < 0)
+		err(EX_OSERR, "Unable to determine the number of cpus");
+
+	/* determine the maximum number of PMCs in any CPU */
+	npmc = 0;
+	for (c = 0; c < ncpu; c++) {
+		if ((t = pmc_npmc(c)) < 0)
+			err(EX_OSERR, "Unable to determine the number of PMCs in "
+			    "CPU %d", c);
+		npmc = t > npmc ? t : npmc;
+	}
+
+	if (npmc == 0)
+		errx(EX_CONFIG, "No PMCs found");
+
+	if ((map = malloc(npmc * ncpu)) == NULL)
+		err(EX_SOFTWARE, "Out of memory");
+
+	(void) memset(map, PMCC_OP_IGNORE, npmc*ncpu);
+
+	error = 0;
+	STAILQ_FOREACH(np, op_list, op_next) {
+
+		cpu = np->op_cpu;
+		pmc = np->op_pmc;
+		op  = np->op_op;
+
+		if (cpu >= ncpu)
+			errx(EX_DATAERR, "CPU id too large: \"%d\"", cpu);
+
+		if (pmc >= npmc)
+			errx(EX_DATAERR, "PMC id too large: \"%d\"", pmc);
+
+#define MARKMAP(M,C,P,V)	do {				\
+		*((M) + (C)*npmc + (P)) = (V);			\
+} while (0)
+
+#define	SET_PMCS(C,P,V)		do {				\
+		if ((P) == PMCC_PMC_ALL) {			\
+			for (j = 0; j < npmc; j++)		\
+				MARKMAP(map, (C), j, (V));	\
+		} else						\
+			MARKMAP(map, (C), (P), (V));		\
+} while (0)
+
+#define MAP(M,C,P)	(*((M) + (C)*npmc + (P)))
+
+		if (cpu == PMCC_CPU_ALL)
+			for (i = 0; i < ncpu; i++)
+				SET_PMCS(i, pmc, op);
+		else
+			SET_PMCS(cpu, pmc, op);
+	}
+
+	/* Configure PMCS */
+	for (i = 0; i < ncpu; i++)
+		for (j = 0; j < npmc; j++) {
+			unsigned char b;
+
+			b = MAP(map, i, j);
+
+			error = 0;
+
+			if (b == PMCC_OP_ENABLE)
+				error = pmc_enable(i, j);
+			else if (b == PMCC_OP_DISABLE)
+				error = pmc_disable(i, j);
+
+			if (error < 0)
+				err(EX_OSERR, "%s of PMC %d on CPU %d failed",
+				    b == PMCC_OP_ENABLE ? "Enable" :
+				    "Disable", j, i);
+		}
+
+	return error;
+}
+
+static int
+pmcc_do_list_state(void)
+{
+	size_t dummy;
+	int c, cpu, n, npmc, ncpu;
+	unsigned int logical_cpus_mask;
+	struct pmc_info *pd;
+	struct pmc_op_getpmcinfo *pi;
+	const struct pmc_op_getcpuinfo *pc;
+
+	if (pmc_cpuinfo(&pc) != 0)
+		err(EX_OSERR, "Unable to determine CPU information");
+
+	dummy = sizeof(logical_cpus_mask);
+	if (sysctlbyname("machdep.logical_cpus_mask", &logical_cpus_mask,
+		&dummy, NULL, 0) < 0)
+		logical_cpus_mask = 0;
+
+	ncpu = pc->pm_ncpu;
+
+	for (c = cpu = 0; cpu < ncpu; cpu++) {
+#if	i386
+		if (pc->pm_cputype == PMC_CPU_INTEL_PIV &&
+		    (logical_cpus_mask & (1 << cpu)))
+			continue; /* skip P4-style 'logical' cpus */
+#endif
+		if (pmc_pmcinfo(cpu, &pi) < 0)
+			err(EX_OSERR, "Unable to get PMC status for CPU %d",
+			    cpu);
+
+		printf("#CPU %d:\n", c++);
+		npmc = pmc_npmc(cpu);
+		printf("#N  NAME             CLASS  STATE    ROW-DISP\n");
+
+		for (n = 0; n < npmc; n++) {
+			pd = &pi->pm_pmcs[n];
+
+			printf(" %-2d %-16s %-6s %-8s %-10s",
+			    n,
+			    pd->pm_name,
+			    pmc_name_of_class(pd->pm_class),
+			    pd->pm_enabled ? "ENABLED" : "DISABLED",
+			    pmc_name_of_disposition(pd->pm_rowdisp));
+
+			if (pd->pm_ownerpid != -1) {
+			        printf(" (pid %d)", pd->pm_ownerpid);
+				printf(" %-32s",
+				    pmc_name_of_event(pd->pm_event));
+				if (PMC_IS_SAMPLING_MODE(pd->pm_mode))
+					printf(" (reload count %jd)",
+					    pd->pm_reloadcount);
+			}
+			printf("\n");
+		}
+		free(pi);
+	}
+	return 0;
+}
+
+static int
+pmcc_do_list_events(void)
+{
+	enum pmc_class c;
+	unsigned int i, j, nevents;
+	const char **eventnamelist;
+	const struct pmc_op_getcpuinfo *ci;
+
+	if (pmc_cpuinfo(&ci) != 0)
+		err(EX_OSERR, "Unable to determine CPU information");
+
+	eventnamelist = NULL;
+
+	for (i = 0; i < ci->pm_nclass; i++) {
+		c = ci->pm_classes[i];
+
+		printf("%s\n", pmc_name_of_class(c));
+		if (pmc_event_names_of_class(c, &eventnamelist, &nevents) < 0)
+			err(EX_OSERR, "ERROR: Cannot find information for "
+			    "event class \"%s\"", pmc_name_of_class(c));
+
+		for (j = 0; j < nevents; j++)
+			printf("\t%s\n", eventnamelist[j]);
+
+		free(eventnamelist);
+	}
+	return 0;
+}
+
+static int
+pmcc_show_statistics(void)
+{
+
+	struct pmc_op_getdriverstats gms;
+
+	if (pmc_get_driver_stats(&gms) < 0)
+		err(EX_OSERR, "ERROR: cannot retrieve driver statistics");
+
+	/*
+	 * Print statistics.
+	 */
+
+#define	PRINT(N,V)	(void) printf("%20s %d\n", (N), gms.pm_##V)
+
+	PRINT("interrupts-processed", intr_processed);
+	PRINT("interrupts-ignored", intr_ignored);
+	PRINT("system-calls", syscalls);
+	PRINT("system-calls-with-errors", syscall_errors);
+
+	return 0;
+}
+
+/*
+ * Main
+ */
+
+int
+main(int argc, char **argv)
+{
+	int error, command, currentcpu, option, pmc;
+	char *dummy;
+	struct pmcc_op *p;
+
+#if DEBUG
+	pmcc_init_debug();
+#endif
+
+	/* parse args */
+
+	currentcpu = PMCC_CPU_ALL;
+	command    = PMCC_PRINT_USAGE;
+	error      = 0;
+
+	STAILQ_INIT(&head);
+
+	while ((option = getopt(argc, argv, ":c:d:e:lLs")) != -1)
+		switch (option) {
+		case 'L':
+			if (command != PMCC_PRINT_USAGE) {
+				error = 1;
+				break;
+			}
+			command = PMCC_PRINT_EVENTS;
+			break;
+
+		case 'c':
+			if (command != PMCC_PRINT_USAGE &&
+			    command != PMCC_ENABLE_DISABLE) {
+				error = 1;
+				break;
+			}
+			command = PMCC_ENABLE_DISABLE;
+
+			if (*optarg == PMCC_CPU_WILDCARD)
+				currentcpu = PMCC_CPU_ALL;
+			else {
+				currentcpu = strtoul(optarg, &dummy, 0);
+				if (*dummy != '\0' || currentcpu < 0)
+					errx(EX_DATAERR,
+					    "\"%s\" is not a valid CPU id",
+					    optarg);
+			}
+			break;
+
+		case 'd':
+		case 'e':
+			if (command != PMCC_PRINT_USAGE &&
+			    command != PMCC_ENABLE_DISABLE) {
+				error = 1;
+				break;
+			}
+			command = PMCC_ENABLE_DISABLE;
+
+			if (*optarg == PMCC_PMC_WILDCARD)
+				pmc = PMCC_PMC_ALL;
+			else {
+				pmc = strtoul(optarg, &dummy, 0);
+				if (*dummy != '\0' || pmc < 0)
+					errx(EX_DATAERR,
+					    "\"%s\" is not a valid PMC id",
+					    optarg);
+			}
+
+			if ((p = malloc(sizeof(*p))) == NULL)
+				err(EX_SOFTWARE, "Out of memory");
+
+			p->op_cpu = currentcpu;
+			p->op_pmc = pmc;
+			p->op_op  = option == 'd' ? PMCC_OP_DISABLE :
+			    PMCC_OP_ENABLE;
+
+			STAILQ_INSERT_TAIL(&head, p, op_next);
+			break;
+
+		case 'l':
+			if (command != PMCC_PRINT_USAGE) {
+				error = 1;
+				break;
+			}
+			command = PMCC_LIST_STATE;
+			break;
+
+		case 's':
+			if (command != PMCC_PRINT_USAGE) {
+				error = 1;
+				break;
+			}
+			command = PMCC_SHOW_STATISTICS;
+			break;
+
+		case ':':
+			errx(EX_USAGE,
+			    "Missing argument to option '-%c'", optopt);
+			break;
+
+		case '?':
+			warnx("Unrecognized option \"-%c\"", optopt);
+			errx(EX_USAGE, usage_message);
+			break;
+
+		default:
+			error = 1;
+			break;
+
+		}
+
+	if (command == PMCC_PRINT_USAGE)
+		(void) errx(EX_USAGE, usage_message);
+
+	if (error)
+		exit(EX_USAGE);
+
+	if (pmc_init() < 0)
+		err(EX_UNAVAILABLE,
+		    "Initialization of the pmc(3) library failed");
+
+	switch (command) {
+	case PMCC_LIST_STATE:
+		error = pmcc_do_list_state();
+		break;
+	case PMCC_PRINT_EVENTS:
+		error = pmcc_do_list_events();
+		break;
+	case PMCC_SHOW_STATISTICS:
+		error = pmcc_show_statistics();
+		break;
+	case PMCC_ENABLE_DISABLE:
+		if (STAILQ_EMPTY(&head))
+			errx(EX_USAGE, "No PMCs specified to enable or disable");
+		error = pmcc_do_enable_disable(&head);
+		break;
+	default:
+		assert(0);
+
+	}
+
+	if (error != 0)
+		err(EX_OSERR, "Command failed");
+	exit(0);
+}
diff --git a/usr.sbin/pmcstat/Makefile b/usr.sbin/pmcstat/Makefile
new file mode 100644
index 0000000..350c024
--- /dev/null
+++ b/usr.sbin/pmcstat/Makefile
@@ -0,0 +1,17 @@
+#
+# $FreeBSD$
+#
+
+PROG=	pmcstat
+MAN=	pmcstat.8
+
+DPADD=	${LIBPMC}
+LDADD=	-lpmc -lm
+
+WARNS=	6
+
+CFLAGS+=	-I${.CURDIR}/../../sys -I${.CURDIR}/../../lib/libpmc
+
+SRCS=	pmcstat.c
+
+.include <bsd.prog.mk>
diff --git a/usr.sbin/pmcstat/pmcstat.8 b/usr.sbin/pmcstat/pmcstat.8
new file mode 100644
index 0000000..75f132b
--- /dev/null
+++ b/usr.sbin/pmcstat/pmcstat.8
@@ -0,0 +1,196 @@
+.\" Copyright (c) 2003 Joseph Koshy.  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.
+.\"
+.\" This software is provided by Joseph Koshy ``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 Joseph Koshy 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd Dec 15, 2003
+.Os
+.Dt PMCSTAT 8
+.Sh NAME
+.Nm pmcstat
+.Nd performance measurement with performance monitoring hardware
+.Sh SYNOPSIS
+.Nm
+.Op Fl C
+.Op Fl O Ar logfilename
+.Op Fl P Ar event-spec
+.Op Fl S Ar event-spec
+.Op Fl c Ar cpu
+.Op Fl d
+.Op Fl n Ar count
+.Op Fl o Ar outputfile
+.Op Fl p Ar event-spec
+.Op Fl s Ar event-spec
+.Op Fl t Ar pid
+.Op Fl w Ar interval
+.Op command Op args
+.Sh DESCRIPTION
+The
+.Nm
+utility measures system performance using the facilities provided by
+.Xr hwpmc 4 .
+.Pp
+The
+.Nm
+utility can measure both hardware events seen by the system as a
+whole, and those seen when a specified process is executing on the
+system's CPUs.
+If a specific process is being targeted (for example,
+if the
+.Fl t Ar pid
+option is specified, or if a command line is specified using
+.Ar command ) ,
+then measurement occurs till the target process exits or
+the
+.Nm
+utility is interrupted by the user.
+If a specific process is not targeted for measurement, then
+.Nm
+will perform system-wide measurements till interrupted by the
+user.
+.Pp
+A given invocation of
+.Nm
+can mix allocations of system-mode and process-mode PMCs, of both
+counting and sampling flavors.
+The values of all counting PMCs are printed in human readable form
+at regular intervals by
+.Nm .
+The output of sampling PMCs is configured to go to log file, for later
+analysis by tools like
+.Xr pmcreport 8 .
+.Pp
+Hardware events to measure are specified to
+.Nm
+using event specifier strings
+.Ar event-spec .
+The syntax of these event specifiers is machine dependent and is
+documented in
+.Xr pmc 3 .
+.Pp
+A process-mode PMC may be configured to be inheritable by the target
+process' current and future children.
+.Sh OPTIONS
+The following options are available:
+.Bl -tag -width indent
+.It Fl C
+Toggle between showing cumulative and incremental counts for
+subsequent counting mode PMCs specified on the command line.
+The default is to show incremental counts.
+.It Fl O Ar logfilename
+Send the output of sampling mode PMCs to
+.Ar logfilename .
+The default file name is
+.Pa pmcstat.out ,
+in the current directory.
+.It Fl P Ar event-spec
+Allocate a process mode sampling PMC measuring hardware events
+specified in
+.Ar event-spec .
+.It Fl S Ar event-spec
+Allocate a system mode sampling PMC measuring hardware events
+specified in
+.Ar event-spec .
+.It Fl c Ar cpu
+Set the cpu for subsequent system mode PMCs specified on the
+command line to
+.Ar cpu .
+The default is to allocate system mode PMCs on CPU zero.
+.It Fl d
+Toggle between process mode PMCs measuring events for the target
+process' current and future children or only measuring events for
+the attached process.
+The default is to measure events for the target process alone.
+.It Fl n Ar rate
+Set the default sampling rate for subsequent sampling mode
+PMCs specified on the command line.
+The default is to configure PMCs to sample the CPU's instruction
+pointer every 65536 events.
+.It Fl o Ar outputfile
+Send the periodic counter output of
+.Nm
+to file
+.Ar outputfile .
+The default is to send output to
+.Pa stderr .
+.It Fl p Ar event-spec
+Allocate a process mode counting PMC measuring hardware events
+specified in
+.Ar event-spec .
+.It Fl s Ar event-spec
+Allocate a system mode counting PMC measuring hardware events
+specified in
+.Ar event-spec .
+.It Fl t Ar pid
+Attach all process mode PMCs allocated to the process with PID
+.Ar pid .
+The option is not allowed in conjunction with specifying a
+command using
+.Ar command .
+.It Fl w Ar secs
+Print the values of all counting mode PMCs every
+.Ar secs
+seconds.
+The argument
+.Ar secs
+may be a fractional value.
+The default interval is 5 seconds.
+.El
+.Pp
+If
+.Ar command
+is specified, it is executed using
+.Xr execvp 3 .
+.Sh EXAMPLES
+To perform system-wide statistical sampling on an AMD Athlon CPU with
+samples taken every 32768 instruction retirals and data being sampled
+to file
+.Dq sample.stat ,
+use:
+.Dl pmccstat -O sample.stat -n 32768 -S k7-retired-instructions
+.Pp
+To execute
+.Dq mozilla
+and measure the number of data cache misses suffered
+by it and its children every 12 seconds on an AMD Athlon, use:
+.Dl pmcstat -d -w 12 -p k7-dc-misses mozilla
+.Sh DIAGNOSTICS
+.Ex -std pmcstat
+.Sh HISTORY
+The
+.Nm
+utility is proposed to be integrated into
+.Fx
+sometime after
+.Fx 5.2 .
+.Nm
+.Bt
+.Sh AUTHORS
+.An Joseph Koshy Aq jkoshy@FreeBSD.org
+.Sh SEE ALSO
+.Xr execvp 3 ,
+.Xr pmc 3 ,
+.Xr hwpmc 4 ,
+.Xr pmccontrol 8 ,
+.Xr pmcreport 8 ,
+.Xr sysctl 8
diff --git a/usr.sbin/pmcstat/pmcstat.c b/usr.sbin/pmcstat/pmcstat.c
new file mode 100644
index 0000000..8dc09dc
--- /dev/null
+++ b/usr.sbin/pmcstat/pmcstat.c
@@ -0,0 +1,728 @@
+/*-
+ * Copyright (c) 2003,2004 Joseph Koshy
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/queue.h>
+#include <sys/time.h>
+#include <sys/ttycom.h>
+#include <sys/wait.h>
+
+#include <assert.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <math.h>
+#include <pmc.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <unistd.h>
+
+/* Operation modes */
+
+#define	FLAG_HAS_PID			0x00000001
+#define	FLAG_HAS_WAIT_INTERVAL		0x00000002
+#define	FLAG_HAS_LOG_FILE		0x00000004
+#define	FLAG_HAS_PROCESS		0x00000008
+#define	FLAG_USING_SAMPLING		0x00000010
+#define	FLAG_USING_COUNTING		0x00000020
+#define	FLAG_USING_PROCESS_PMC		0x00000040
+
+#define	DEFAULT_SAMPLE_COUNT		65536
+#define	DEFAULT_WAIT_INTERVAL		5.0
+#define	DEFAULT_DISPLAY_HEIGHT		23
+#define	DEFAULT_LOGFILE_NAME		"pmcstat.out"
+
+#define	PRINT_HEADER_PREFIX		"# "
+#define	READPIPEFD			0
+#define	WRITEPIPEFD			1
+#define	NPIPEFD				2
+
+struct pmcstat_ev {
+	STAILQ_ENTRY(pmcstat_ev) ev_next;
+	char	       *ev_spec;  /* event specification */
+	char	       *ev_name;  /* (derived) event name */
+	enum pmc_mode	ev_mode;  /* desired mode */
+	int		ev_count; /* associated count if in sampling mode */
+	int		ev_cpu;	  /* specific cpu if requested */
+	int		ev_descendants; /* attach to descendants */
+	int		ev_cumulative;  /* show cumulative counts */
+	int		ev_fieldwidth;  /* print width */
+	int		ev_fieldskip;   /* #leading spaces */
+	pmc_value_t	ev_saved; /* saved value for incremental counts */
+	pmc_id_t	ev_pmcid; /* allocated ID */
+};
+
+struct pmcstat_args {
+	int	pa_flags;
+	pid_t	pa_pid;
+	FILE   *pa_outputfile;
+	FILE   *pa_logfile;
+	double  pa_interval;
+	int	pa_argc;
+	char  **pa_argv;
+	STAILQ_HEAD(, pmcstat_ev) pa_head;
+} args;
+
+int	pmcstat_interrupt = 0;
+int	pmcstat_displayheight = DEFAULT_DISPLAY_HEIGHT;
+int	pmcstat_pipefd[NPIPEFD];
+int	pmcstat_kq;
+
+/* Function prototypes */
+void pmcstat_cleanup(struct pmcstat_args *_a);
+void pmcstat_print_counters(struct pmcstat_args *_a);
+void pmcstat_print_headers(struct pmcstat_args *_a);
+void pmcstat_print_pmcs(struct pmcstat_args *_a);
+void pmcstat_setup_process(struct pmcstat_args *_a);
+void pmcstat_show_usage(void);
+void pmcstat_start_pmcs(struct pmcstat_args *_a);
+void pmcstat_start_process(struct pmcstat_args *_a);
+
+
+/*
+ * cleanup
+ */
+
+void
+pmcstat_cleanup(struct pmcstat_args *a)
+{
+	struct pmcstat_ev *ev, *tmp;
+
+	/* de-configure the log file if present. */
+	if (a->pa_flags & FLAG_USING_SAMPLING) {
+		(void) pmc_configure_logfile(-1);
+		(void) fclose(a->pa_logfile);
+	}
+
+	/* release allocated PMCs. */
+	STAILQ_FOREACH_SAFE(ev, &a->pa_head, ev_next, tmp)
+	    if (ev->ev_pmcid != PMC_ID_INVALID) {
+		if (pmc_release(ev->ev_pmcid) < 0)
+			err(EX_OSERR, "ERROR: cannot release pmc "
+			    "%d \"%s\"", ev->ev_pmcid, ev->ev_name);
+		free(ev->ev_name);
+		free(ev->ev_spec);
+		STAILQ_REMOVE(&a->pa_head, ev, pmcstat_ev, ev_next);
+		free(ev);
+	    }
+}
+
+void
+pmcstat_start_pmcs(struct pmcstat_args *a)
+{
+	struct pmcstat_ev *ev;
+
+	STAILQ_FOREACH(ev, &args.pa_head, ev_next) {
+
+	    assert(ev->ev_pmcid != PMC_ID_INVALID);
+
+	    if (pmc_start(ev->ev_pmcid) < 0) {
+	        warn("ERROR: Cannot start pmc %d \"%s\"",
+		    ev->ev_pmcid, ev->ev_name);
+		pmcstat_cleanup(a);
+	    }
+	}
+
+}
+
+void
+pmcstat_print_headers(struct pmcstat_args *a)
+{
+	struct pmcstat_ev *ev;
+	int c;
+
+	(void) fprintf(a->pa_outputfile, PRINT_HEADER_PREFIX);
+
+	STAILQ_FOREACH(ev, &a->pa_head, ev_next) {
+		if (PMC_IS_SAMPLING_MODE(ev->ev_mode))
+			continue;
+
+		c = PMC_IS_SYSTEM_MODE(ev->ev_mode) ? 's' : 'p';
+
+		if (ev->ev_fieldskip != 0) {
+			(void) fprintf(a->pa_outputfile, "%*s%c/%*s ",
+			    ev->ev_fieldskip, "", c,
+			    ev->ev_fieldwidth - ev->ev_fieldskip - 2,
+			    ev->ev_name);
+		} else
+			(void) fprintf(a->pa_outputfile, "%c/%*s ",
+			    c, ev->ev_fieldwidth - 2, ev->ev_name);
+	}
+
+	(void) fflush(a->pa_outputfile);
+}
+
+void
+pmcstat_print_counters(struct pmcstat_args *a)
+{
+	int extra_width;
+	struct pmcstat_ev *ev;
+	pmc_value_t value;
+
+	extra_width = sizeof(PRINT_HEADER_PREFIX) - 1;
+
+	STAILQ_FOREACH(ev, &a->pa_head, ev_next) {
+
+		/* skip sampling mode counters */
+		if (PMC_IS_SAMPLING_MODE(ev->ev_mode))
+			continue;
+
+		if (pmc_read(ev->ev_pmcid, &value) < 0)
+			err(EX_OSERR, "ERROR: Cannot read pmc "
+			    "\"%s\"", ev->ev_name);
+
+		(void) fprintf(a->pa_outputfile, "%*ju ",
+		    ev->ev_fieldwidth + extra_width, (uintmax_t)
+		    ev->ev_cumulative ? value : (value - ev->ev_saved));
+		if (ev->ev_cumulative == 0)
+			ev->ev_saved = value;
+		extra_width = 0;
+	}
+
+	(void) fflush(a->pa_outputfile);
+}
+
+/*
+ * Print output
+ */
+
+void
+pmcstat_print_pmcs(struct pmcstat_args *a)
+{
+	static int linecount = 0;
+
+	if (++linecount > pmcstat_displayheight) {
+		(void) fprintf(a->pa_outputfile, "\n");
+		linecount = 1;
+	}
+
+	if (linecount == 1)
+		pmcstat_print_headers(a);
+
+	(void) fprintf(a->pa_outputfile, "\n");
+	pmcstat_print_counters(a);
+
+	return;
+}
+
+/*
+ * Do process profiling
+ *
+ * If a pid was specified, attach each allocated PMC to the target
+ * process.  Otherwise, fork a child and attach the PMCs to the child,
+ * and have the child exec() the target program.
+ */
+
+void
+pmcstat_setup_process(struct pmcstat_args *a)
+{
+	char token;
+	struct pmcstat_ev *ev;
+	struct kevent kev;
+
+	if (a->pa_flags & FLAG_HAS_PID) {
+
+		STAILQ_FOREACH(ev, &args.pa_head, ev_next)
+		    if (pmc_attach(ev->ev_pmcid, a->pa_pid) != 0)
+			    err(EX_OSERR, "ERROR: cannot attach pmc \"%s\" to "
+				"process %d", ev->ev_name, (int) a->pa_pid);
+
+	} else {
+
+		/*
+		 * We need to fork a new process and startup the child
+		 * using execvp().  Before doing the exec() the child
+		 * process reads its pipe for a token so that the parent
+		 * can finish doing its pmc_attach() calls.
+		 */
+
+		if (pipe(pmcstat_pipefd) < 0)
+			err(EX_OSERR, "ERROR: cannot create pipe");
+
+		switch (a->pa_pid = fork()) {
+		case -1:
+			err(EX_OSERR, "ERROR: cannot fork");
+			/*NOTREACHED*/
+
+		case 0:		/* child */
+
+			/* wait for our parent to signal us */
+			(void) close(pmcstat_pipefd[WRITEPIPEFD]);
+			if (read(pmcstat_pipefd[READPIPEFD], &token, 1) < 0)
+				err(EX_OSERR, "ERROR (child): cannot read "
+				    "token");
+			(void) close(pmcstat_pipefd[READPIPEFD]);
+
+			/* exec() the program requested */
+			execvp(*args.pa_argv, args.pa_argv);
+			err(EX_OSERR, "ERROR (child): execvp failed");
+			/*NOTREACHED*/
+
+		default:	/* parent */
+
+			(void) close(pmcstat_pipefd[READPIPEFD]);
+
+			/* attach all our PMCs to the child */
+			STAILQ_FOREACH(ev, &args.pa_head, ev_next)
+			    if (PMC_IS_VIRTUAL_MODE(ev->ev_mode) &&
+				pmc_attach(ev->ev_pmcid, a->pa_pid) != 0)
+				    err(EX_OSERR, "ERROR: cannot attach pmc "
+					"\"%s\" to process %d", ev->ev_name,
+					(int) a->pa_pid);
+
+		}
+	}
+
+	/* Ask to be notified via a kevent when the child exits */
+	EV_SET(&kev, a->pa_pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, 0);
+
+	if (kevent(pmcstat_kq, &kev, 1, NULL, 0, NULL) < 0)
+		err(EX_OSERR, "ERROR: cannot monitor process %d",
+		    a->pa_pid);
+
+	return;
+}
+
+void
+pmcstat_start_process(struct pmcstat_args *a)
+{
+
+	/* nothing to do: target is already running */
+	if (a->pa_flags & FLAG_HAS_PID)
+		return;
+
+	/* write token to child to state that we are ready */
+	if (write(pmcstat_pipefd[WRITEPIPEFD], "+", 1) != 1)
+		err(EX_OSERR, "ERROR: write failed");
+
+	(void) close(pmcstat_pipefd[WRITEPIPEFD]);
+}
+
+void
+pmcstat_show_usage(void)
+{
+	errx(EX_USAGE,
+	    "[options] [commandline]\n"
+	    "\t Measure process and/or system performance using hardware\n"
+	    "\t performance monitoring counters.\n"
+	    "\t Options include:\n"
+	    "\t -C\t\t toggle showing cumulative counts\n"
+	    "\t -O file\t set sampling log file to \"file\"\n"
+	    "\t -P spec\t allocate process-private sampling PMC\n"
+	    "\t -S spec\t allocate system-wide sampling PMC\n"
+	    "\t -c cpu\t\t set default cpu\n"
+	    "\t -d\t\t toggle tracking descendants\n"
+	    "\t -n rate\t set sampling rate\n"
+	    "\t -o file\t send print output to \"file\"\n"
+	    "\t -p spec\t allocate process-private counting PMC\n"
+	    "\t -s spec\t allocate system-wide counting PMC\n"
+	    "\t -t pid\t attach to running process with pid \"pid\"\n"
+	    "\t -w secs\t set printing time interval"
+	);
+}
+
+/*
+ * Main
+ */
+
+int
+main(int argc, char **argv)
+{
+	double interval;
+	int option, npmc, ncpu;
+	int c, current_cpu, current_sampling_count;
+	int running;
+	int do_descendants, use_cumulative_counts;
+	pid_t pid;
+	char *end;
+	struct pmcstat_ev *ev;
+	struct pmc_op_getpmcinfo *ppmci;
+	struct sigaction sa;
+	struct kevent kev;
+	struct winsize ws;
+
+	current_cpu 		= 0;
+	current_sampling_count  = DEFAULT_SAMPLE_COUNT;
+	do_descendants          = 0;
+	use_cumulative_counts   = 0;
+	args.pa_flags		= 0;
+	args.pa_pid		= (pid_t) -1;
+	args.pa_logfile		= NULL;
+	args.pa_outputfile	= stderr;
+	args.pa_interval	= DEFAULT_WAIT_INTERVAL;
+	STAILQ_INIT(&args.pa_head);
+
+	ev = NULL;
+
+	while ((option = getopt(argc, argv, "CO:P:S:c:dn:o:p:s:t:w:")) != -1)
+		switch (option) {
+		case 'C':	/* cumulative values */
+			use_cumulative_counts = !use_cumulative_counts;
+			break;
+
+		case 'c':	/* CPU */
+			current_cpu = strtol(optarg, &end, 0);
+			if (*end != '\0' || current_cpu < 0)
+				errx(EX_USAGE,
+				    "ERROR: Illegal CPU number \"%s\"",
+				    optarg);
+
+			break;
+
+		case 'd':	/* toggle descendents */
+			do_descendants = !do_descendants;
+			break;
+
+		case 'p':	/* process virtual counting PMC */
+		case 's':	/* system-wide counting PMC */
+		case 'P':	/* process virtual sampling PMC */
+		case 'S':	/* system-wide sampling PMC */
+			if ((ev = malloc(sizeof(*ev))) == NULL)
+				errx(EX_SOFTWARE, "ERROR: Out of memory");
+
+			switch (option) {
+			case 'p': ev->ev_mode = PMC_MODE_TC; break;
+			case 's': ev->ev_mode = PMC_MODE_SC; break;
+			case 'P': ev->ev_mode = PMC_MODE_TS; break;
+			case 'S': ev->ev_mode = PMC_MODE_SS; break;
+			}
+
+			if (option == 'P' || option == 'p')
+				args.pa_flags |= FLAG_USING_PROCESS_PMC;
+
+			if (option == 'P' || option == 'S')
+				args.pa_flags |= FLAG_USING_SAMPLING;
+
+			if (option == 'p' || option == 's')
+				args.pa_flags |= FLAG_USING_COUNTING;
+
+			ev->ev_spec  = strdup(optarg);
+
+			if (option == 'S' || option == 'P')
+				ev->ev_count = current_sampling_count;
+			else
+				ev->ev_count = -1;
+
+			if (option == 'S' || option == 's')
+				ev->ev_cpu = current_cpu;
+			else
+				ev->ev_cpu = PMC_CPU_ANY;
+
+			ev->ev_descendants = do_descendants;
+			ev->ev_cumulative  = use_cumulative_counts;
+
+			ev->ev_saved = 0LL;
+			ev->ev_pmcid = PMC_ID_INVALID;
+
+			/* extract event name */
+			c = strcspn(optarg, ", \t");
+			ev->ev_name = malloc(c + 1);
+			(void) strncpy(ev->ev_name, optarg, c);
+			*(ev->ev_name + c) = '\0';
+
+			STAILQ_INSERT_TAIL(&args.pa_head, ev, ev_next);
+
+			break;
+
+		case 'n':	/* sampling count */
+			current_sampling_count = strtol(optarg, &end, 0);
+			if (*end != '\0' || current_sampling_count <= 0)
+				errx(EX_USAGE,
+				    "ERROR: Illegal count value \"%s\"",
+				    optarg);
+			break;
+
+		case 'o':	/* outputfile */
+			if (args.pa_outputfile != NULL)
+				(void) fclose(args.pa_outputfile);
+
+			if ((args.pa_outputfile = fopen(optarg, "w")) == NULL)
+				errx(EX_OSERR, "ERROR: cannot open \"%s\" for "
+				    "writing", optarg);
+
+		case 'O':	/* sampling output */
+			if (args.pa_logfile != NULL)
+				(void) fclose(args.pa_logfile);
+
+			if ((args.pa_logfile = fopen(optarg, "w")) == NULL)
+				errx(EX_OSERR, "ERROR: cannot open \"%s\" for "
+				    "writing", optarg);
+			break;
+
+		case 't':	/* target pid */
+			pid = strtol(optarg, &end, 0);
+			if (*end != '\0' || pid <= 0)
+				errx(EX_USAGE, "ERROR: Illegal pid value "
+				    "\"%s\"", optarg);
+
+			args.pa_flags |= FLAG_HAS_PID;
+			args.pa_pid = pid;
+
+			break;
+
+		case 'w':	/* wait interval */
+			interval = strtod(optarg, &end);
+			if (*end != '\0' || interval <= 0)
+				errx(EX_USAGE, "ERROR: Illegal wait interval "
+				    "value \"%s\"", optarg);
+			args.pa_flags |= FLAG_HAS_WAIT_INTERVAL;
+			args.pa_interval = interval;
+
+			break;
+
+		case '?':
+		default:
+			pmcstat_show_usage();
+			break;
+
+		}
+
+	args.pa_argc = (argc -= optind);
+	args.pa_argv = (argv += optind);
+
+	if (argc)
+		args.pa_flags |= FLAG_HAS_PROCESS;
+
+	/*
+	 * Check invocation syntax.
+	 */
+
+	if (STAILQ_EMPTY(&args.pa_head)) {
+		warnx("ERROR: At least one PMC event must be specified");
+		pmcstat_show_usage();
+	}
+
+	if (argc == 0) {
+		if (args.pa_pid == -1) {
+			if (args.pa_flags & FLAG_USING_PROCESS_PMC)
+				errx(EX_USAGE, "ERROR: the -P or -p options "
+				    "require a target process");
+		} else if ((args.pa_flags & FLAG_USING_PROCESS_PMC) == 0)
+			errx(EX_USAGE,
+			    "ERROR: option -t requires a process-mode pmc "
+			    "specification");
+	} else if (args.pa_pid != -1)
+		errx(EX_USAGE,
+		    "ERROR: option -t cannot be specified with a command "
+		    "name");
+
+	if (pmc_init() < 0)
+		err(EX_UNAVAILABLE,
+		    "ERROR: Initialization of the pmc(3) library failed");
+
+	if ((ncpu = pmc_ncpu()) < 0)
+		err(EX_OSERR, "ERROR: Cannot determine the number CPUs "
+		    "on the system");
+
+	if ((npmc = pmc_npmc(0)) < 0) /* assume all CPUs are identical */
+		err(EX_OSERR, "ERROR: Cannot determine the number of PMCs "
+		    "on CPU %d", 0);
+
+	/*
+	 * Allocate PMCs.
+	 */
+
+	if (pmc_pmcinfo(0, &ppmci) < 0)
+		err(EX_OSERR, "ERROR: cannot retrieve pmc information");
+
+	assert(ppmci != NULL);
+
+	STAILQ_FOREACH(ev, &args.pa_head, ev_next)
+	    if (pmc_allocate(ev->ev_spec, ev->ev_mode,
+		    (ev->ev_descendants ? PMC_F_DESCENDANTS : 0),
+		    ev->ev_cpu, &ev->ev_pmcid) < 0)
+		    err(EX_OSERR, "ERROR: Cannot allocate %s-mode pmc with "
+			"specification \"%s\"",
+			PMC_IS_SYSTEM_MODE(ev->ev_mode) ? "system" : "process",
+			ev->ev_spec);
+
+	/* compute printout widths */
+	STAILQ_FOREACH(ev, &args.pa_head, ev_next) {
+		int pmc_width;
+		int pmc_display_width;
+		int pmc_header_width;
+
+		pmc_width = ppmci->pm_pmcs[ev->ev_pmcid].pm_width;
+		pmc_header_width = strlen(ev->ev_name) + 2; /* prefix '%c|' */
+		pmc_display_width = (int) floor(pmc_width / 3.32193) + 1;
+
+		if (pmc_header_width > pmc_display_width) {
+			ev->ev_fieldskip = 0;
+			ev->ev_fieldwidth = pmc_header_width;
+		} else {
+			ev->ev_fieldskip = pmc_display_width -
+			    pmc_header_width;
+			ev->ev_fieldwidth = pmc_display_width;
+		}
+	}
+
+	/* Allocate a kqueue */
+	if ((pmcstat_kq = kqueue()) < 0)
+		err(EX_OSERR, "ERROR: Cannot allocate kqueue");
+
+	/*
+	 * If our output is being set to a terminal, register a handler
+	 * for window size changes.
+	 */
+
+	if (isatty(fileno(args.pa_outputfile))) {
+
+		if (ioctl(fileno(args.pa_outputfile), TIOCGWINSZ, &ws) < 0)
+			err(EX_OSERR, "ERROR: Cannot determine window size");
+
+		pmcstat_displayheight = ws.ws_row - 1;
+
+		EV_SET(&kev, SIGWINCH, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
+
+		if (kevent(pmcstat_kq, &kev, 1, NULL, 0, NULL) < 0)
+			err(EX_OSERR, "ERROR: Cannot register kevent for "
+			    "SIGWINCH");
+	}
+
+	EV_SET(&kev, SIGINT, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
+
+	if (kevent(pmcstat_kq, &kev, 1, NULL, 0, NULL) < 0)
+		err(EX_OSERR, "ERROR: Cannot register kevent for SIGINT");
+
+	if (args.pa_flags & FLAG_USING_SAMPLING) {
+
+		/*
+		 * configure log file
+		 */
+
+		if (args.pa_logfile == NULL)
+			if ((args.pa_logfile =
+				fopen(DEFAULT_LOGFILE_NAME, "w")) == NULL)
+				err(EX_CANTCREAT, "ERROR: Cannot open sampling "
+				    "log file \"%s\"", DEFAULT_LOGFILE_NAME);
+
+		if (pmc_configure_logfile(fileno(args.pa_logfile)) < 0)
+			err(EX_OSERR, "ERROR: Cannot configure sampling "
+			    "log");
+
+		STAILQ_FOREACH(ev, &args.pa_head, ev_next)
+		    if (PMC_IS_SAMPLING_MODE(ev->ev_mode) &&
+			pmc_set(ev->ev_pmcid, ev->ev_count) < 0)
+			    err(EX_OSERR, "ERROR: Cannot set sampling count "
+				"for PMC \"%s\"", ev->ev_name);
+	}
+
+	/* setup a timer for any counting mode PMCs */
+	if (args.pa_flags & FLAG_USING_COUNTING) {
+		EV_SET(&kev, 0, EVFILT_TIMER, EV_ADD, 0,
+		    args.pa_interval * 1000, NULL);
+
+		if (kevent(pmcstat_kq, &kev, 1, NULL, 0, NULL) < 0)
+			err(EX_OSERR, "ERROR: Cannot register kevent for "
+			    "timer");
+	}
+
+	/* attach PMCs to the target process, starting it if specified */
+	if (args.pa_flags & FLAG_HAS_PROCESS)
+		pmcstat_setup_process(&args);
+
+	/* start the pmcs */
+	pmcstat_start_pmcs(&args);
+
+	/* start the (commandline) process if needed */
+	if (args.pa_flags & FLAG_HAS_PROCESS)
+		pmcstat_start_process(&args);
+
+	/* Handle SIGINT using the kqueue loop */
+	sa.sa_handler = SIG_IGN;
+	sa.sa_flags   = 0;
+	(void) sigemptyset(&sa.sa_mask);
+
+	if (sigaction(SIGINT, &sa, NULL) < 0)
+		err(EX_OSERR, "ERROR: Cannot install signal handler");
+
+	/*
+	 * loop till either the target process (if any) exits, or we
+	 * are killed by a SIGINT.
+	 */
+
+	running = 1;
+	do {
+		if ((c = kevent(pmcstat_kq, NULL, 0, &kev, 1, NULL)) <= 0) {
+			if (errno != EINTR)
+				err(EX_OSERR, "ERROR: kevent failed");
+			else
+				continue;
+		}
+
+		if (kev.flags & EV_ERROR)
+			errc(EX_OSERR, kev.data, "ERROR: kevent failed");
+
+		switch (kev.filter) {
+		case EVFILT_PROC: /* target process exited */
+			running = 0;
+			/* FALLTHROUGH */
+
+		case EVFILT_TIMER: /* print out counting PMCs */
+			pmcstat_print_pmcs(&args);
+
+			if (running == 0) /* final newline */
+				(void) fprintf(args.pa_outputfile, "\n");
+			break;
+
+		case EVFILT_SIGNAL:
+			if (kev.ident == SIGINT) {
+				/* pass the signal on to the child process */
+				if ((args.pa_flags & FLAG_HAS_PROCESS) &&
+				    (args.pa_flags & FLAG_HAS_PID) == 0)
+					if (kill(args.pa_pid, SIGINT) != 0)
+						err(EX_OSERR, "cannot kill "
+						    "child");
+				running = 0;
+			} else if (kev.ident == SIGWINCH) {
+				if (ioctl(fileno(args.pa_outputfile),
+					TIOCGWINSZ, &ws) < 0)
+				    err(EX_OSERR, "ERROR: Cannot determine "
+					"window size");
+				pmcstat_displayheight = ws.ws_row - 1;
+			} else
+				assert(0);
+
+			break;
+		}
+
+	} while (running);
+
+	pmcstat_cleanup(&args);
+
+	return 0;
+}