1 files changed, 341 insertions, 0 deletions
diff --git a/cddl/contrib/opensolaris/uts/common/dtrace/lockstat.c b/cddl/contrib/opensolaris/uts/common/dtrace/lockstat.c
new file mode 100644
index 0000000..3eb76a0
--- /dev/null
+++ b/cddl/contrib/opensolaris/uts/common/dtrace/lockstat.c
@@ -0,0 +1,341 @@
+/*
+ * 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
+ */
+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/open.h>
+#include <sys/file.h>
+#include <sys/conf.h>
+#include <sys/modctl.h>
+#include <sys/cmn_err.h>
+#include <sys/bitmap.h>
+#include <sys/debug.h>
+#include <sys/kmem.h>
+#include <sys/errno.h>
+#include <sys/sysmacros.h>
+#include <sys/lockstat.h>
+#include <sys/atomic.h>
+#include <sys/dtrace.h>
+
+#include <sys/ddi.h>
+#include <sys/sunddi.h>
+
+typedef struct lockstat_probe {
+	const char	*lsp_func;
+	const char	*lsp_name;
+	int		lsp_probe;
+	dtrace_id_t	lsp_id;
+} lockstat_probe_t;
+
+lockstat_probe_t lockstat_probes[] =
+{
+	{ LS_MUTEX_ENTER,	LSA_ACQUIRE,	LS_MUTEX_ENTER_ACQUIRE },
+	{ LS_MUTEX_ENTER,	LSA_BLOCK,	LS_MUTEX_ENTER_BLOCK },
+	{ LS_MUTEX_ENTER,	LSA_SPIN,	LS_MUTEX_ENTER_SPIN },
+	{ LS_MUTEX_EXIT,	LSA_RELEASE,	LS_MUTEX_EXIT_RELEASE },
+	{ LS_MUTEX_DESTROY,	LSA_RELEASE,	LS_MUTEX_DESTROY_RELEASE },
+	{ LS_MUTEX_TRYENTER,	LSA_ACQUIRE,	LS_MUTEX_TRYENTER_ACQUIRE },
+	{ LS_LOCK_SET,		LSS_ACQUIRE,	LS_LOCK_SET_ACQUIRE },
+	{ LS_LOCK_SET,		LSS_SPIN,	LS_LOCK_SET_SPIN },
+	{ LS_LOCK_SET_SPL,	LSS_ACQUIRE,	LS_LOCK_SET_SPL_ACQUIRE },
+	{ LS_LOCK_SET_SPL,	LSS_SPIN,	LS_LOCK_SET_SPL_SPIN },
+	{ LS_LOCK_TRY,		LSS_ACQUIRE,	LS_LOCK_TRY_ACQUIRE },
+	{ LS_LOCK_CLEAR,	LSS_RELEASE,	LS_LOCK_CLEAR_RELEASE },
+	{ LS_LOCK_CLEAR_SPLX,	LSS_RELEASE,	LS_LOCK_CLEAR_SPLX_RELEASE },
+	{ LS_CLOCK_UNLOCK,	LSS_RELEASE,	LS_CLOCK_UNLOCK_RELEASE },
+	{ LS_RW_ENTER,		LSR_ACQUIRE,	LS_RW_ENTER_ACQUIRE },
+	{ LS_RW_ENTER,		LSR_BLOCK,	LS_RW_ENTER_BLOCK },
+	{ LS_RW_EXIT,		LSR_RELEASE,	LS_RW_EXIT_RELEASE },
+	{ LS_RW_TRYENTER,	LSR_ACQUIRE,	LS_RW_TRYENTER_ACQUIRE },
+	{ LS_RW_TRYUPGRADE,	LSR_UPGRADE,	LS_RW_TRYUPGRADE_UPGRADE },
+	{ LS_RW_DOWNGRADE,	LSR_DOWNGRADE,	LS_RW_DOWNGRADE_DOWNGRADE },
+	{ LS_THREAD_LOCK,	LST_SPIN,	LS_THREAD_LOCK_SPIN },
+	{ LS_THREAD_LOCK_HIGH,	LST_SPIN,	LS_THREAD_LOCK_HIGH_SPIN },
+	{ NULL }
+};
+
+static dev_info_t	*lockstat_devi;	/* saved in xxattach() for xxinfo() */
+static kmutex_t		lockstat_test;	/* for testing purposes only */
+static dtrace_provider_id_t lockstat_id;
+
+/*ARGSUSED*/
+static void
+lockstat_enable(void *arg, dtrace_id_t id, void *parg)
+{
+	lockstat_probe_t *probe = parg;
+
+	ASSERT(!lockstat_probemap[probe->lsp_probe]);
+
+	lockstat_probemap[probe->lsp_probe] = id;
+	membar_producer();
+
+	lockstat_hot_patch();
+	membar_producer();
+
+	/*
+	 * Immediately generate a record for the lockstat_test mutex
+	 * to verify that the mutex hot-patch code worked as expected.
+	 */
+	mutex_enter(&lockstat_test);
+	mutex_exit(&lockstat_test);
+}
+
+/*ARGSUSED*/
+static void
+lockstat_disable(void *arg, dtrace_id_t id, void *parg)
+{
+	lockstat_probe_t *probe = parg;
+	int i;
+
+	ASSERT(lockstat_probemap[probe->lsp_probe]);
+
+	lockstat_probemap[probe->lsp_probe] = 0;
+	lockstat_hot_patch();
+	membar_producer();
+
+	/*
+	 * See if we have any probes left enabled.
+	 */
+	for (i = 0; i < LS_NPROBES; i++) {
+		if (lockstat_probemap[i]) {
+			/*
+			 * This probe is still enabled.  We don't need to deal
+			 * with waiting for all threads to be out of the
+			 * lockstat critical sections; just return.
+			 */
+			return;
+		}
+	}
+
+	/*
+	 * The delay() here isn't as cheesy as you might think.  We don't
+	 * want to busy-loop in the kernel, so we have to give up the
+	 * CPU between calls to lockstat_active_threads(); that much is
+	 * obvious.  But the reason it's a do..while loop rather than a
+	 * while loop is subtle.  The memory barrier above guarantees that
+	 * no threads will enter the lockstat code from this point forward.
+	 * However, another thread could already be executing lockstat code
+	 * without our knowledge if the update to its t_lockstat field hasn't
+	 * cleared its CPU's store buffer.  Delaying for one clock tick
+	 * guarantees that either (1) the thread will have *ample* time to
+	 * complete its work, or (2) the thread will be preempted, in which
+	 * case it will have to grab and release a dispatcher lock, which
+	 * will flush that CPU's store buffer.  Either way we're covered.
+	 */
+	do {
+		delay(1);
+	} while (lockstat_active_threads());
+}
+
+/*ARGSUSED*/
+static int
+lockstat_open(dev_t *devp, int flag, int otyp, cred_t *cred_p)
+{
+	return (0);
+}
+
+/* ARGSUSED */
+static int
+lockstat_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
+{
+	int error;
+
+	switch (infocmd) {
+	case DDI_INFO_DEVT2DEVINFO:
+		*result = (void *) lockstat_devi;
+		error = DDI_SUCCESS;
+		break;
+	case DDI_INFO_DEVT2INSTANCE:
+		*result = (void *)0;
+		error = DDI_SUCCESS;
+		break;
+	default:
+		error = DDI_FAILURE;
+	}
+	return (error);
+}
+
+/*ARGSUSED*/
+static void
+lockstat_provide(void *arg, const dtrace_probedesc_t *desc)
+{
+	int i = 0;
+
+	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
+		lockstat_probe_t *probe = &lockstat_probes[i];
+
+		if (dtrace_probe_lookup(lockstat_id, "genunix",
+		    probe->lsp_func, probe->lsp_name) != 0)
+			continue;
+
+		ASSERT(!probe->lsp_id);
+		probe->lsp_id = dtrace_probe_create(lockstat_id,
+		    "genunix", probe->lsp_func, probe->lsp_name,
+		    1, probe);
+	}
+}
+
+/*ARGSUSED*/
+static void
+lockstat_destroy(void *arg, dtrace_id_t id, void *parg)
+{
+	lockstat_probe_t *probe = parg;
+
+	ASSERT(!lockstat_probemap[probe->lsp_probe]);
+	probe->lsp_id = 0;
+}
+
+static dtrace_pattr_t lockstat_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_UNKNOWN },
+{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
+{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
+};
+
+static dtrace_pops_t lockstat_pops = {
+	lockstat_provide,
+	NULL,
+	lockstat_enable,
+	lockstat_disable,
+	NULL,
+	NULL,
+	NULL,
+	NULL,
+	NULL,
+	lockstat_destroy
+};
+
+static int
+lockstat_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
+{
+	switch (cmd) {
+	case DDI_ATTACH:
+		break;
+	case DDI_RESUME:
+		return (DDI_SUCCESS);
+	default:
+		return (DDI_FAILURE);
+	}
+
+	if (ddi_create_minor_node(devi, "lockstat", S_IFCHR, 0,
+	    DDI_PSEUDO, 0) == DDI_FAILURE ||
+	    dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_KERNEL,
+	    NULL, &lockstat_pops, NULL, &lockstat_id) != 0) {
+		ddi_remove_minor_node(devi, NULL);
+		return (DDI_FAILURE);
+	}
+
+	lockstat_probe = dtrace_probe;
+	membar_producer();
+
+	ddi_report_dev(devi);
+	lockstat_devi = devi;
+	return (DDI_SUCCESS);
+}
+
+static int
+lockstat_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
+{
+	switch (cmd) {
+	case DDI_DETACH:
+		break;
+	case DDI_SUSPEND:
+		return (DDI_SUCCESS);
+	default:
+		return (DDI_FAILURE);
+	}
+
+	if (dtrace_unregister(lockstat_id) != 0)
+		return (DDI_FAILURE);
+
+	ddi_remove_minor_node(devi, NULL);
+	return (DDI_SUCCESS);
+}
+
+/*
+ * Configuration data structures
+ */
+static struct cb_ops lockstat_cb_ops = {
+	lockstat_open,		/* open */
+	nodev,			/* close */
+	nulldev,		/* strategy */
+	nulldev,		/* print */
+	nodev,			/* dump */
+	nodev,			/* read */
+	nodev,			/* write */
+	nodev,			/* ioctl */
+	nodev,			/* devmap */
+	nodev,			/* mmap */
+	nodev,			/* segmap */
+	nochpoll,		/* poll */
+	ddi_prop_op,		/* cb_prop_op */
+	0,			/* streamtab */
+	D_MP | D_NEW		/* Driver compatibility flag */
+};
+
+static struct dev_ops lockstat_ops = {
+	DEVO_REV,		/* devo_rev, */
+	0,			/* refcnt */
+	lockstat_info,		/* getinfo */
+	nulldev,		/* identify */
+	nulldev,		/* probe */
+	lockstat_attach,	/* attach */
+	lockstat_detach,	/* detach */
+	nulldev,		/* reset */
+	&lockstat_cb_ops,	/* cb_ops */
+	NULL,			/* bus_ops */
+};
+
+static struct modldrv modldrv = {
+	&mod_driverops,		/* Type of module.  This one is a driver */
+	"Lock Statistics %I%",	/* name of module */
+	&lockstat_ops,		/* driver ops */
+};
+
+static struct modlinkage modlinkage = {
+	MODREV_1, (void *)&modldrv, NULL
+};
+
+int
+_init(void)
+{
+	return (mod_install(&modlinkage));
+}
+
+int
+_fini(void)
+{
+	return (mod_remove(&modlinkage));
+}
+
+int
+_info(struct modinfo *modinfop)
+{
+	return (mod_info(&modlinkage, modinfop));
+}