Custom DTrace kernel module files plus FreeBSD-specific DTrace providers.

1 files changed, 531 insertions, 0 deletions

diff --git a/sys/cddl/dev/profile/profile.c b/sys/cddl/dev/profile/profile.c
new file mode 100644
index 000000000000..ea52e2ea3623
--- /dev/null
+++ b/sys/cddl/dev/profile/profile.c
@@ -0,0 +1,531 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * Portions Copyright 2006-2008 John Birrell jb@freebsd.org
+ *
+ * $FreeBSD$
+ *
+ */
+
+/*
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/cpuvar.h>
+#include <sys/fcntl.h>
+#include <sys/filio.h>
+#include <sys/kdb.h>
+#include <sys/kernel.h>
+#include <sys/kmem.h>
+#include <sys/kthread.h>
+#include <sys/limits.h>
+#include <sys/linker.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/poll.h>
+#include <sys/proc.h>
+#include <sys/selinfo.h>
+#include <sys/smp.h>
+#include <sys/uio.h>
+#include <sys/unistd.h>
+#include <machine/stdarg.h>
+
+#include <sys/cyclic.h>
+#include <sys/dtrace.h>
+#include <sys/dtrace_bsd.h>
+
+#define	PROF_NAMELEN		15
+
+#define	PROF_PROFILE		0
+#define	PROF_TICK		1
+#define	PROF_PREFIX_PROFILE	"profile-"
+#define	PROF_PREFIX_TICK	"tick-"
+
+/*
+ * Regardless of platform, there are five artificial frames in the case of the
+ * profile provider:
+ *
+ *	profile_fire
+ *	cyclic_expire
+ *	cyclic_fire
+ *	[ cbe ]
+ *	[ locore ]
+ *
+ * On amd64, there are two frames associated with locore:  one in locore, and
+ * another in common interrupt dispatch code.  (i386 has not been modified to
+ * use this common layer.)  Further, on i386, the interrupted instruction
+ * appears as its own stack frame.  All of this means that we need to add one
+ * frame for amd64, and then take one away for both amd64 and i386.
+ *
+ * On SPARC, the picture is further complicated because the compiler
+ * optimizes away tail-calls -- so the following frames are optimized away:
+ *
+ * 	profile_fire
+ *	cyclic_expire
+ *
+ * This gives three frames.  However, on DEBUG kernels, the cyclic_expire
+ * frame cannot be tail-call eliminated, yielding four frames in this case.
+ *
+ * All of the above constraints lead to the mess below.  Yes, the profile
+ * provider should ideally figure this out on-the-fly by hiting one of its own
+ * probes and then walking its own stack trace.  This is complicated, however,
+ * and the static definition doesn't seem to be overly brittle.  Still, we
+ * allow for a manual override in case we get it completely wrong.
+ */
+#ifdef __amd64
+#define	PROF_ARTIFICIAL_FRAMES	7
+#else
+#ifdef __i386
+#define	PROF_ARTIFICIAL_FRAMES	6
+#else
+#ifdef __sparc
+#ifdef DEBUG
+#define	PROF_ARTIFICIAL_FRAMES	4
+#else
+#define	PROF_ARTIFICIAL_FRAMES	3
+#endif
+#endif
+#endif
+#endif
+
+typedef struct profile_probe {
+	char		prof_name[PROF_NAMELEN];
+	dtrace_id_t	prof_id;
+	int		prof_kind;
+	hrtime_t	prof_interval;
+	cyclic_id_t	prof_cyclic;
+} profile_probe_t;
+
+typedef struct profile_probe_percpu {
+	hrtime_t	profc_expected;
+	hrtime_t	profc_interval;
+	profile_probe_t	*profc_probe;
+} profile_probe_percpu_t;
+
+static d_open_t	profile_open;
+static int	profile_unload(void);
+static void	profile_create(hrtime_t, char *, int);
+static void	profile_destroy(void *, dtrace_id_t, void *);
+static void	profile_enable(void *, dtrace_id_t, void *);
+static void	profile_disable(void *, dtrace_id_t, void *);
+static void	profile_load(void *);
+static void	profile_provide(void *, dtrace_probedesc_t *);
+
+static int profile_rates[] = {
+    97, 199, 499, 997, 1999,
+    4001, 4999, 0, 0, 0,
+    0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0
+};
+
+static int profile_ticks[] = {
+    1, 10, 100, 500, 1000,
+    5000, 0, 0, 0, 0,
+    0, 0, 0, 0, 0
+};
+
+/*
+ * profile_max defines the upper bound on the number of profile probes that
+ * can exist (this is to prevent malicious or clumsy users from exhausing
+ * system resources by creating a slew of profile probes). At mod load time,
+ * this gets its value from PROFILE_MAX_DEFAULT or profile-max-probes if it's
+ * present in the profile.conf file.
+ */
+#define	PROFILE_MAX_DEFAULT	1000	/* default max. number of probes */
+static uint32_t profile_max = PROFILE_MAX_DEFAULT;
+					/* maximum number of profile probes */
+static uint32_t profile_total;		/* current number of profile probes */
+
+static struct cdevsw profile_cdevsw = {
+	.d_version	= D_VERSION,
+	.d_open		= profile_open,
+	.d_name		= "profile",
+};
+
+static dtrace_pattr_t profile_attr = {
+{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
+{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
+{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
+{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
+{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
+};
+
+static dtrace_pops_t profile_pops = {
+	profile_provide,
+	NULL,
+	profile_enable,
+	profile_disable,
+	NULL,
+	NULL,
+	NULL,
+	NULL,
+	NULL,
+	profile_destroy
+};
+
+static struct cdev		*profile_cdev;
+static dtrace_provider_id_t	profile_id;
+static hrtime_t			profile_interval_min = NANOSEC / 5000;	/* 5000 hz */
+static int			profile_aframes = 0;			/* override */
+
+static void
+profile_fire(void *arg)
+{
+	profile_probe_percpu_t *pcpu = arg;
+	profile_probe_t *prof = pcpu->profc_probe;
+	hrtime_t late;
+	solaris_cpu_t *c = &solaris_cpu[curcpu];
+
+	late = gethrtime() - pcpu->profc_expected;
+	pcpu->profc_expected += pcpu->profc_interval;
+
+	dtrace_probe(prof->prof_id, c->cpu_profile_pc,
+	    c->cpu_profile_upc, late, 0, 0);
+}
+
+static void
+profile_tick(void *arg)
+{
+	profile_probe_t *prof = arg;
+	solaris_cpu_t *c = &solaris_cpu[curcpu];
+
+	dtrace_probe(prof->prof_id, c->cpu_profile_pc,
+	    c->cpu_profile_upc, 0, 0, 0);
+}
+
+static void
+profile_create(hrtime_t interval, char *name, int kind)
+{
+	profile_probe_t *prof;
+
+	if (interval < profile_interval_min)
+		return;
+
+	if (dtrace_probe_lookup(profile_id, NULL, NULL, name) != 0)
+		return;
+
+	atomic_add_32(&profile_total, 1);
+	if (profile_total > profile_max) {
+		atomic_add_32(&profile_total, -1);
+		return;
+	}
+
+	prof = kmem_zalloc(sizeof (profile_probe_t), KM_SLEEP);
+	(void) strcpy(prof->prof_name, name);
+	prof->prof_interval = interval;
+	prof->prof_cyclic = CYCLIC_NONE;
+	prof->prof_kind = kind;
+	prof->prof_id = dtrace_probe_create(profile_id,
+	    NULL, NULL, name,
+	    profile_aframes ? profile_aframes : PROF_ARTIFICIAL_FRAMES, prof);
+}
+
+/*ARGSUSED*/
+static void
+profile_provide(void *arg, dtrace_probedesc_t *desc)
+{
+	int i, j, rate, kind;
+	hrtime_t val = 0, mult = 1, len = 0;
+	char *name, *suffix = NULL;
+
+	const struct {
+		char *prefix;
+		int kind;
+	} types[] = {
+		{ PROF_PREFIX_PROFILE, PROF_PROFILE },
+		{ PROF_PREFIX_TICK, PROF_TICK },
+		{ 0, 0 }
+	};
+
+	const struct {
+		char *name;
+		hrtime_t mult;
+	} suffixes[] = {
+		{ "ns", 	NANOSEC / NANOSEC },
+		{ "nsec",	NANOSEC / NANOSEC },
+		{ "us",		NANOSEC / MICROSEC },
+		{ "usec",	NANOSEC / MICROSEC },
+		{ "ms",		NANOSEC / MILLISEC },
+		{ "msec",	NANOSEC / MILLISEC },
+		{ "s",		NANOSEC / SEC },
+		{ "sec",	NANOSEC / SEC },
+		{ "m",		NANOSEC * (hrtime_t)60 },
+		{ "min",	NANOSEC * (hrtime_t)60 },
+		{ "h",		NANOSEC * (hrtime_t)(60 * 60) },
+		{ "hour",	NANOSEC * (hrtime_t)(60 * 60) },
+		{ "d",		NANOSEC * (hrtime_t)(24 * 60 * 60) },
+		{ "day",	NANOSEC * (hrtime_t)(24 * 60 * 60) },
+		{ "hz",		0 },
+		{ NULL }
+	};
+
+	if (desc == NULL) {
+		char n[PROF_NAMELEN];
+
+		/*
+		 * If no description was provided, provide all of our probes.
+		 */
+		for (i = 0; i < sizeof (profile_rates) / sizeof (int); i++) {
+			if ((rate = profile_rates[i]) == 0)
+				continue;
+
+			(void) snprintf(n, PROF_NAMELEN, "%s%d",
+			    PROF_PREFIX_PROFILE, rate);
+			profile_create(NANOSEC / rate, n, PROF_PROFILE);
+		}
+
+		for (i = 0; i < sizeof (profile_ticks) / sizeof (int); i++) {
+			if ((rate = profile_ticks[i]) == 0)
+				continue;
+
+			(void) snprintf(n, PROF_NAMELEN, "%s%d",
+			    PROF_PREFIX_TICK, rate);
+			profile_create(NANOSEC / rate, n, PROF_TICK);
+		}
+
+		return;
+	}
+
+	name = desc->dtpd_name;
+
+	for (i = 0; types[i].prefix != NULL; i++) {
+		len = strlen(types[i].prefix);
+
+		if (strncmp(name, types[i].prefix, len) != 0)
+			continue;
+		break;
+	}
+
+	if (types[i].prefix == NULL)
+		return;
+
+	kind = types[i].kind;
+	j = strlen(name) - len;
+
+	/*
+	 * We need to start before any time suffix.
+	 */
+	for (j = strlen(name); j >= len; j--) {
+		if (name[j] >= '0' && name[j] <= '9')
+			break;
+		suffix = &name[j];
+	}
+
+	ASSERT(suffix != NULL);
+
+	/*
+	 * Now determine the numerical value present in the probe name.
+	 */
+	for (; j >= len; j--) {
+		if (name[j] < '0' || name[j] > '9')
+			return;
+
+		val += (name[j] - '0') * mult;
+		mult *= (hrtime_t)10;
+	}
+
+	if (val == 0)
+		return;
+
+	/*
+	 * Look-up the suffix to determine the multiplier.
+	 */
+	for (i = 0, mult = 0; suffixes[i].name != NULL; i++) {
+		if (strcasecmp(suffixes[i].name, suffix) == 0) {
+			mult = suffixes[i].mult;
+			break;
+		}
+	}
+
+	if (suffixes[i].name == NULL && *suffix != '\0')
+		return;
+
+	if (mult == 0) {
+		/*
+		 * The default is frequency-per-second.
+		 */
+		val = NANOSEC / val;
+	} else {
+		val *= mult;
+	}
+
+	profile_create(val, name, kind);
+}
+
+/* ARGSUSED */
+static void
+profile_destroy(void *arg, dtrace_id_t id, void *parg)
+{
+	profile_probe_t *prof = parg;
+
+	ASSERT(prof->prof_cyclic == CYCLIC_NONE);
+	kmem_free(prof, sizeof (profile_probe_t));
+
+	ASSERT(profile_total >= 1);
+	atomic_add_32(&profile_total, -1);
+}
+
+/*ARGSUSED*/
+static void
+profile_online(void *arg, cpu_t *cpu, cyc_handler_t *hdlr, cyc_time_t *when)
+{
+	profile_probe_t *prof = arg;
+	profile_probe_percpu_t *pcpu;
+
+	pcpu = kmem_zalloc(sizeof (profile_probe_percpu_t), KM_SLEEP);
+	pcpu->profc_probe = prof;
+
+	hdlr->cyh_func = profile_fire;
+	hdlr->cyh_arg = pcpu;
+
+	when->cyt_interval = prof->prof_interval;
+	when->cyt_when = gethrtime() + when->cyt_interval;
+
+	pcpu->profc_expected = when->cyt_when;
+	pcpu->profc_interval = when->cyt_interval;
+}
+
+/*ARGSUSED*/
+static void
+profile_offline(void *arg, cpu_t *cpu, void *oarg)
+{
+	profile_probe_percpu_t *pcpu = oarg;
+
+	ASSERT(pcpu->profc_probe == arg);
+	kmem_free(pcpu, sizeof (profile_probe_percpu_t));
+}
+
+/* ARGSUSED */
+static void
+profile_enable(void *arg, dtrace_id_t id, void *parg)
+{
+	profile_probe_t *prof = parg;
+	cyc_omni_handler_t omni;
+	cyc_handler_t hdlr;
+	cyc_time_t when;
+
+	ASSERT(prof->prof_interval != 0);
+	ASSERT(MUTEX_HELD(&cpu_lock));
+
+	if (prof->prof_kind == PROF_TICK) {
+		hdlr.cyh_func = profile_tick;
+		hdlr.cyh_arg = prof;
+
+		when.cyt_interval = prof->prof_interval;
+		when.cyt_when = gethrtime() + when.cyt_interval;
+	} else {
+		ASSERT(prof->prof_kind == PROF_PROFILE);
+		omni.cyo_online = profile_online;
+		omni.cyo_offline = profile_offline;
+		omni.cyo_arg = prof;
+	}
+
+	if (prof->prof_kind == PROF_TICK) {
+		prof->prof_cyclic = cyclic_add(&hdlr, &when);
+	} else {
+		prof->prof_cyclic = cyclic_add_omni(&omni);
+	}
+}
+
+/* ARGSUSED */
+static void
+profile_disable(void *arg, dtrace_id_t id, void *parg)
+{
+	profile_probe_t *prof = parg;
+
+	ASSERT(prof->prof_cyclic != CYCLIC_NONE);
+	ASSERT(MUTEX_HELD(&cpu_lock));
+
+	cyclic_remove(prof->prof_cyclic);
+	prof->prof_cyclic = CYCLIC_NONE;
+}
+
+static void
+profile_load(void *dummy)
+{
+	/* Create the /dev/dtrace/profile entry. */
+	profile_cdev = make_dev(&profile_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
+	    "dtrace/profile");
+
+	if (dtrace_register("profile", &profile_attr, DTRACE_PRIV_USER,
+	    NULL, &profile_pops, NULL, &profile_id) != 0)
+		return;
+}
+
+
+static int
+profile_unload()
+{
+	int error = 0;
+
+	if ((error = dtrace_unregister(profile_id)) != 0)
+		return (error);
+
+	destroy_dev(profile_cdev);
+
+	return (error);
+}
+
+/* ARGSUSED */
+static int
+profile_modevent(module_t mod __unused, int type, void *data __unused)
+{
+	int error = 0;
+
+	switch (type) {
+	case MOD_LOAD:
+		break;
+
+	case MOD_UNLOAD:
+		break;
+
+	case MOD_SHUTDOWN:
+		break;
+
+	default:
+		error = EOPNOTSUPP;
+		break;
+
+	}
+	return (error);
+}
+
+/* ARGSUSED */
+static int
+profile_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused)
+{
+	return (0);
+}
+
+SYSINIT(profile_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, profile_load, NULL);
+SYSUNINIT(profile_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, profile_unload, NULL);
+
+DEV_MODULE(profile, profile_modevent, NULL);
+MODULE_VERSION(profile, 1);
+MODULE_DEPEND(profile, dtrace, 1, 1, 1);
+MODULE_DEPEND(profile, cyclic, 1, 1, 1);
+MODULE_DEPEND(profile, opensolaris, 1, 1, 1);