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

1 files changed, 254 insertions, 0 deletions

diff --git a/sys/cddl/dev/sdt/sdt.c b/sys/cddl/dev/sdt/sdt.c
new file mode 100644
index 0000000..d5d4172
--- /dev/null
+++ b/sys/cddl/dev/sdt/sdt.c
@@ -0,0 +1,254 @@
+/*
+ * 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
+ *
+ * $FreeBSD$
+ *
+ */
+
+#ifndef KDTRACE_HOOKS
+#define KDTRACE_HOOKS
+#endif
+
+#include <sys/cdefs.h>
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/kernel.h>
+#include <sys/limits.h>
+#include <sys/lock.h>
+#include <sys/linker.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+
+#include <sys/dtrace.h>
+#include <sys/sdt.h>
+
+#define SDT_ADDR2NDX(addr) (((uintptr_t)(addr)) >> 4)
+
+static d_open_t sdt_open;
+static int	sdt_unload(void);
+static void	sdt_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *);
+static void	sdt_provide_probes(void *, dtrace_probedesc_t *);
+static void	sdt_destroy(void *, dtrace_id_t, void *);
+static void	sdt_enable(void *, dtrace_id_t, void *);
+static void	sdt_disable(void *, dtrace_id_t, void *);
+static void	sdt_load(void *);
+
+static struct cdevsw sdt_cdevsw = {
+	.d_version	= D_VERSION,
+	.d_open		= sdt_open,
+	.d_name		= "sdt",
+};
+
+static dtrace_pattr_t sdt_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 sdt_pops = {
+	sdt_provide_probes,
+	NULL,
+	sdt_enable,
+	sdt_disable,
+	NULL,
+	NULL,
+	sdt_getargdesc,
+	NULL,
+	NULL,
+	sdt_destroy
+};
+
+static struct cdev		*sdt_cdev;
+
+static int
+sdt_argtype_callback(struct sdt_argtype *argtype, void *arg)
+{
+	dtrace_argdesc_t *desc = arg;
+
+	if (desc->dtargd_ndx == argtype->ndx) {
+		desc->dtargd_mapping = desc->dtargd_ndx; /* XXX */
+		strlcpy(desc->dtargd_native, argtype->type,
+		    sizeof(desc->dtargd_native));
+		desc->dtargd_xlate[0] = '\0'; /* XXX */
+	}
+
+	return (0);
+}
+
+static void
+sdt_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc)
+{
+	struct sdt_probe *probe = parg;
+
+	if (desc->dtargd_ndx < probe->n_args)
+		(void) (sdt_argtype_listall(probe, sdt_argtype_callback, desc));
+	else
+		desc->dtargd_ndx = DTRACE_ARGNONE;
+
+	return;
+}
+
+static int
+sdt_probe_callback(struct sdt_probe *probe, void *arg __unused)
+{
+	struct sdt_provider *prov = probe->prov;
+	char mod[64];
+	char func[64];
+	char name[64];
+
+	/*
+	 * Unfortunately this is necessary because the Solaris DTrace
+	 * code mixes consts and non-consts with casts to override
+	 * the incompatibilies. On FreeBSD, we use strict warnings
+	 * in gcc, so we have to respect const vs non-const.
+	 */
+	strlcpy(mod, probe->mod, sizeof(mod));
+	strlcpy(func, probe->func, sizeof(func));
+	strlcpy(name, probe->name, sizeof(name));
+
+	if (dtrace_probe_lookup(prov->id, mod, func, name) != 0)
+		return (0);
+
+	(void) dtrace_probe_create(prov->id, probe->mod, probe->func,
+	    probe->name, 0, probe);
+
+	return (0);
+}
+
+static int
+sdt_provider_entry(struct sdt_provider *prov, void *arg)
+{
+	return (sdt_probe_listall(prov, sdt_probe_callback, NULL));
+}
+
+static void
+sdt_provide_probes(void *arg, dtrace_probedesc_t *desc)
+{
+	if (desc != NULL)
+		return;
+
+	(void) sdt_provider_listall(sdt_provider_entry, NULL);
+}
+
+static void
+sdt_destroy(void *arg, dtrace_id_t id, void *parg)
+{
+	/* Nothing to do here. */
+}
+
+static void
+sdt_enable(void *arg, dtrace_id_t id, void *parg)
+{
+	struct sdt_probe *probe = parg;
+
+	probe->id = id;
+}
+
+static void
+sdt_disable(void *arg, dtrace_id_t id, void *parg)
+{
+	struct sdt_probe *probe = parg;
+
+	probe->id = 0;
+}
+
+static int
+sdt_provider_reg_callback(struct sdt_provider *prov, void *arg __unused)
+{
+	return (dtrace_register(prov->name, &sdt_attr, DTRACE_PRIV_USER,
+	    NULL, &sdt_pops, NULL, (dtrace_provider_id_t *) &prov->id));
+}
+
+static void
+sdt_load(void *dummy)
+{
+	/* Create the /dev/dtrace/sdt entry. */
+	sdt_cdev = make_dev(&sdt_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
+	    "dtrace/sdt");
+
+	sdt_probe_func = dtrace_probe;
+
+	(void) sdt_provider_listall(sdt_provider_reg_callback, NULL);
+}
+
+static int
+sdt_provider_unreg_callback(struct sdt_provider *prov, void *arg __unused)
+{
+	return (dtrace_unregister(prov->id));
+}
+
+static int
+sdt_unload()
+{
+	int error = 0;
+
+	sdt_probe_func = sdt_probe_stub;
+
+	(void) sdt_provider_listall(sdt_provider_unreg_callback, NULL);
+	
+	destroy_dev(sdt_cdev);
+
+	return (error);
+}
+
+/* ARGSUSED */
+static int
+sdt_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
+sdt_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused)
+{
+	return (0);
+}
+
+SYSINIT(sdt_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, sdt_load, NULL);
+SYSUNINIT(sdt_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, sdt_unload, NULL);
+
+DEV_MODULE(sdt, sdt_modevent, NULL);
+MODULE_VERSION(sdt, 1);
+MODULE_DEPEND(sdt, dtrace, 1, 1, 1);
+MODULE_DEPEND(sdt, opensolaris, 1, 1, 1);