Move dtnfsclient.c in the cddl tree to nfs_kdtrace.c in the nfsclient

directory, since it's under a BSD license, and this keeps NFS internals-
aware tracing parts close to NFS.

MFC after:	1 month
Suggested by:	jhb

1 files changed, 545 insertions, 0 deletions

diff --git a/sys/nfsclient/nfs_kdtrace.c b/sys/nfsclient/nfs_kdtrace.c
new file mode 100644
index 0000000..8444ae2
--- /dev/null
+++ b/sys/nfsclient/nfs_kdtrace.c
@@ -0,0 +1,545 @@
+/*-
+ * Copyright (c) 2009 Robert N. M. Watson
+ * All rights reserved.
+ *
+ * This software was developed at the University of Cambridge Computer
+ * Laboratory with support from a grant from Google, Inc.
+ *
+ * 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/param.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+
+#include <sys/dtrace.h>
+#include <sys/dtrace_bsd.h>
+
+#include <nfs/nfsproto.h>
+
+/*
+ * dtnfsclient is a DTrace provider that tracks the intent to perform RPCs
+ * in the NFS client, as well as acess to and maintenance of the access and
+ * attribute caches.  This is not quite the same as RPCs, because NFS may
+ * issue multiple RPC transactions in the event that authentication fails,
+ * there's a jukebox error, or none at all if the access or attribute cache
+ * hits.  However, it cleanly represents the logical layer between RPC
+ * transmission and vnode/vfs operations, providing access to state linking
+ * the two.
+ */
+
+static int	dtnfsclient_unload(void);
+static void	dtnfsclient_getargdesc(void *, dtrace_id_t, void *,
+		    dtrace_argdesc_t *);
+static void	dtnfsclient_provide(void *, dtrace_probedesc_t *);
+static void	dtnfsclient_destroy(void *, dtrace_id_t, void *);
+static void	dtnfsclient_enable(void *, dtrace_id_t, void *);
+static void	dtnfsclient_disable(void *, dtrace_id_t, void *);
+static void	dtnfsclient_load(void *);
+
+static dtrace_pattr_t dtnfsclient_attr = {
+{ DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
+{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
+{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
+{ DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
+{ DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
+};
+
+/*
+ * Descrition of NFSv3 and (optional) NFSv2 probes for a procedure.
+ */
+struct dtnfsclient_rpc {
+	char		*nr_v3_name;
+	char		*nr_v2_name;	/* Or NULL if none. */
+
+	/*
+	 * IDs for the start and done cases, for both NFSv2 and NFSv3.
+	 */
+	uint32_t	 nr_v2_id_start, nr_v2_id_done;
+	uint32_t	 nr_v3_id_start, nr_v3_id_done;
+};
+
+/*
+ * This table is indexed by NFSv3 procedure number, but also used for NFSv2
+ * procedure names.
+ */
+static struct dtnfsclient_rpc	dtnfsclient_rpcs[NFS_NPROCS] = {
+	{ "null", "null" },
+	{ "getattr", "getattr" },
+	{ "setattr", "setattr" },
+	{ "lookup", "lookup" },
+	{ "access" },
+	{ "readlink", "readlink" },
+	{ "read", "read" },
+	{ "write", "write" },
+	{ "create", "create" },
+	{ "mkdir", "mkdir" },
+	{ "symlink", "symlink" },
+	{ "mknod" },
+	{ "remove", "remove" },
+	{ "rmdir", "rmdir" },
+	{ "rename", "rename" },
+	{ "link", "link" },
+	{ "readdir", "readdir" },
+	{ "readdirplus" },
+	{ "fsstat", "statfs" },
+	{ "fsinfo" },
+	{ "pathconf" },
+	{ "commit" },
+	{ "noop" },
+};
+
+/*
+ * Module name strings.
+ */
+static char	*dtnfsclient_accesscache_str = "accesscache";
+static char	*dtnfsclient_attrcache_str = "attrcache";
+static char	*dtnfsclient_nfs2_str = "nfs2";
+static char	*dtnfsclient_nfs3_str = "nfs3";
+
+/*
+ * Function name strings.
+ */
+static char	*dtnfsclient_flush_str = "flush";
+static char	*dtnfsclient_load_str = "load";
+static char	*dtnfsclient_get_str = "get";
+
+/*
+ * Name strings.
+ */
+static char	*dtnfsclient_done_str = "done";
+static char	*dtnfsclient_hit_str = "hit";
+static char	*dtnfsclient_miss_str = "miss";
+static char	*dtnfsclient_start_str = "start";
+
+static dtrace_pops_t dtnfsclient_pops = {
+	dtnfsclient_provide,
+	NULL,
+	dtnfsclient_enable,
+	dtnfsclient_disable,
+	NULL,
+	NULL,
+	dtnfsclient_getargdesc,
+	NULL,
+	NULL,
+	dtnfsclient_destroy
+};
+
+static dtrace_provider_id_t	dtnfsclient_id;
+
+/*
+ * Most probes are generated from the above RPC table, but for access and
+ * attribute caches, we have specific IDs we recognize and handle specially
+ * in various spots.
+ */
+extern uint32_t	nfsclient_accesscache_flush_done_id;
+extern uint32_t	nfsclient_accesscache_get_hit_id;
+extern uint32_t	nfsclient_accesscache_get_miss_id;
+extern uint32_t	nfsclient_accesscache_load_done_id;
+
+extern uint32_t	nfsclient_attrcache_flush_done_id;
+extern uint32_t	nfsclient_attrcache_get_hit_id;
+extern uint32_t	nfsclient_attrcache_get_miss_id;
+extern uint32_t	nfsclient_attrcache_load_done_id;
+
+/*
+ * When tracing on a procedure is enabled, the DTrace ID for an RPC event is
+ * stored in one of these two NFS client-allocated arrays; 0 indicates that
+ * the event is not being traced so probes should not be called.
+ *
+ * For simplicity, we allocate both v2 and v3 arrays as NFS_NPROCS, and the
+ * v2 array is simply sparse.
+ */
+extern uint32_t			nfsclient_nfs2_start_probes[NFS_NPROCS];
+extern uint32_t			nfsclient_nfs2_done_probes[NFS_NPROCS];
+
+extern uint32_t			nfsclient_nfs3_start_probes[NFS_NPROCS];
+extern uint32_t			nfsclient_nfs3_done_probes[NFS_NPROCS];
+
+/*
+ * Look up a DTrace probe ID to see if it's associated with a "done" event --
+ * if so, we will return a fourth argument type of "int".
+ */
+static int
+dtnfs23_isdoneprobe(dtrace_id_t id)
+{
+	int i;
+
+	for (i = 0; i < NFS_NPROCS; i++) {
+		if (dtnfsclient_rpcs[i].nr_v3_id_done == id ||
+		    dtnfsclient_rpcs[i].nr_v2_id_done == id)
+			return (1);
+	}
+	return (0);
+}
+
+static void
+dtnfsclient_getargdesc(void *arg, dtrace_id_t id, void *parg,
+    dtrace_argdesc_t *desc)
+{
+	const char *p = NULL;
+
+	if (id == nfsclient_accesscache_flush_done_id ||
+	    id == nfsclient_attrcache_flush_done_id ||
+	    id == nfsclient_attrcache_get_miss_id) {
+		switch (desc->dtargd_ndx) {
+		case 0:
+			p = "struct vnode *";
+			break;
+		default:
+			desc->dtargd_ndx = DTRACE_ARGNONE;
+			break;
+		}
+	} else if (id == nfsclient_accesscache_get_hit_id ||
+	    id == nfsclient_accesscache_get_miss_id) {
+		switch (desc->dtargd_ndx) {
+		case 0:
+			p = "struct vnode *";
+			break;
+		case 1:
+			p = "uid_t";
+			break;
+		case 2:
+			p = "uint32_t";
+			break;
+		default:
+			desc->dtargd_ndx = DTRACE_ARGNONE;
+			break;
+		}
+	} else if (id == nfsclient_accesscache_load_done_id) {
+		switch (desc->dtargd_ndx) {
+		case 0:
+			p = "struct vnode *";
+			break;
+		case 1:
+			p = "uid_t";
+			break;
+		case 2:
+			p = "uint32_t";
+			break;
+		case 3:
+			p = "int";
+			break;
+		default:
+			desc->dtargd_ndx = DTRACE_ARGNONE;
+			break;
+		}
+	} else if (id == nfsclient_attrcache_get_hit_id) {
+		switch (desc->dtargd_ndx) {
+		case 0:
+			p = "struct vnode *";
+			break;
+		case 1:
+			p = "struct vattr *";
+			break;
+		default:
+			desc->dtargd_ndx = DTRACE_ARGNONE;
+			break;
+		}
+	} else if (id == nfsclient_attrcache_load_done_id) {
+		switch (desc->dtargd_ndx) {
+		case 0:
+			p = "struct vnode *";
+			break;
+		case 1:
+			p = "struct vattr *";
+			break;
+		case 2:
+			p = "int";
+			break;
+		default:
+			desc->dtargd_ndx = DTRACE_ARGNONE;
+			break;
+		}
+	} else {
+		switch (desc->dtargd_ndx) {
+		case 0:
+			p = "struct vnode *";
+			break;
+		case 1:
+			p = "struct mbuf *";
+			break;
+		case 2:
+			p = "struct ucred *";
+			break;
+		case 3:
+			p = "int";
+			break;
+		case 4:
+			if (dtnfs23_isdoneprobe(id)) {
+				p = "int";
+				break;
+			}
+			/* FALLSTHROUGH */
+		default:
+			desc->dtargd_ndx = DTRACE_ARGNONE;
+			break;
+		}
+	}
+	if (p != NULL)
+		strlcpy(desc->dtargd_native, p, sizeof(desc->dtargd_native));
+}
+
+static void
+dtnfsclient_provide(void *arg, dtrace_probedesc_t *desc)
+{
+	int i;
+
+	if (desc != NULL)
+		return;
+
+	/*
+	 * Register access cache probes.
+	 */
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_accesscache_str,
+	    dtnfsclient_flush_str, dtnfsclient_done_str) == 0) {
+		nfsclient_accesscache_flush_done_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_accesscache_str,
+		    dtnfsclient_flush_str, dtnfsclient_done_str, 0, NULL);
+	}
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_accesscache_str,
+	    dtnfsclient_get_str, dtnfsclient_hit_str) == 0) {
+		nfsclient_accesscache_get_hit_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_accesscache_str,
+		    dtnfsclient_get_str, dtnfsclient_hit_str, 0, NULL);
+	}
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_accesscache_str,
+	    dtnfsclient_get_str, dtnfsclient_miss_str) == 0) {
+		nfsclient_accesscache_get_miss_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_accesscache_str,
+		    dtnfsclient_get_str, dtnfsclient_miss_str, 0, NULL);
+	}
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_accesscache_str,
+	    dtnfsclient_load_str, dtnfsclient_done_str) == 0) {
+		nfsclient_accesscache_load_done_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_accesscache_str,
+		    dtnfsclient_load_str, dtnfsclient_done_str, 0, NULL);
+	}
+
+	/*
+	 * Register attribute cache probes.
+	 */
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_attrcache_str,
+	    dtnfsclient_flush_str, dtnfsclient_done_str) == 0) {
+		nfsclient_attrcache_flush_done_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_attrcache_str,
+		    dtnfsclient_flush_str, dtnfsclient_done_str, 0, NULL);
+	}
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_attrcache_str,
+	    dtnfsclient_get_str, dtnfsclient_hit_str) == 0) {
+		nfsclient_attrcache_get_hit_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_attrcache_str,
+		    dtnfsclient_get_str, dtnfsclient_hit_str, 0, NULL);
+	}
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_attrcache_str,
+	    dtnfsclient_get_str, dtnfsclient_miss_str) == 0) {
+		nfsclient_attrcache_get_miss_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_attrcache_str,
+		    dtnfsclient_get_str, dtnfsclient_miss_str, 0, NULL);
+	}
+	if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_attrcache_str,
+	    dtnfsclient_load_str, dtnfsclient_done_str) == 0) {
+		nfsclient_attrcache_load_done_id = dtrace_probe_create(
+		    dtnfsclient_id, dtnfsclient_attrcache_str,
+		    dtnfsclient_load_str, dtnfsclient_done_str, 0, NULL);
+	}
+
+	/*
+	 * Register NFSv2 RPC procedures; note sparseness check for each slot
+	 * in the NFSv3 procnum-indexed array.
+	 */
+	for (i = 0; i < NFS_NPROCS; i++) {
+		if (dtnfsclient_rpcs[i].nr_v2_name != NULL &&
+		    dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_nfs2_str,
+		    dtnfsclient_rpcs[i].nr_v2_name, dtnfsclient_start_str) ==
+		    0) {
+			dtnfsclient_rpcs[i].nr_v2_id_start =
+			    dtrace_probe_create(dtnfsclient_id,
+			    dtnfsclient_nfs2_str,
+			    dtnfsclient_rpcs[i].nr_v2_name,
+			    dtnfsclient_start_str, 0,
+			    &nfsclient_nfs2_start_probes[i]);
+		}
+		if (dtnfsclient_rpcs[i].nr_v2_name != NULL &&
+		    dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_nfs2_str,
+		    dtnfsclient_rpcs[i].nr_v2_name, dtnfsclient_done_str) ==
+		    0) {
+			dtnfsclient_rpcs[i].nr_v2_id_done = 
+			    dtrace_probe_create(dtnfsclient_id,
+			    dtnfsclient_nfs2_str,
+			    dtnfsclient_rpcs[i].nr_v2_name,
+			    dtnfsclient_done_str, 0,
+			    &nfsclient_nfs2_done_probes[i]);
+		}
+	}
+
+	/*
+	 * Register NFSv3 RPC procedures.
+	 */
+	for (i = 0; i < NFS_NPROCS; i++) {
+		if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_nfs3_str,
+		    dtnfsclient_rpcs[i].nr_v3_name, dtnfsclient_start_str) ==
+		    0) {
+			dtnfsclient_rpcs[i].nr_v3_id_start =
+			    dtrace_probe_create(dtnfsclient_id,
+			    dtnfsclient_nfs3_str,
+			    dtnfsclient_rpcs[i].nr_v3_name,
+			    dtnfsclient_start_str, 0,
+			    &nfsclient_nfs3_start_probes[i]);
+		}
+		if (dtrace_probe_lookup(dtnfsclient_id, dtnfsclient_nfs3_str,
+		    dtnfsclient_rpcs[i].nr_v3_name, dtnfsclient_done_str) ==
+		    0) {
+			dtnfsclient_rpcs[i].nr_v3_id_done = 
+			    dtrace_probe_create(dtnfsclient_id,
+			    dtnfsclient_nfs3_str,
+			    dtnfsclient_rpcs[i].nr_v3_name,
+			    dtnfsclient_done_str, 0,
+			    &nfsclient_nfs3_done_probes[i]);
+		}
+	}
+}
+
+static void
+dtnfsclient_destroy(void *arg, dtrace_id_t id, void *parg)
+{
+}
+
+static void
+dtnfsclient_enable(void *arg, dtrace_id_t id, void *parg)
+{
+	uint32_t *p = parg;
+	void *f = dtrace_probe;
+
+	if (id == nfsclient_accesscache_flush_done_id)
+		dtrace_nfsclient_accesscache_flush_done_probe = f;
+	else if (id == nfsclient_accesscache_get_hit_id)
+		dtrace_nfsclient_accesscache_get_hit_probe = f;
+	else if (id == nfsclient_accesscache_get_miss_id)
+		dtrace_nfsclient_accesscache_get_miss_probe = f;
+	else if (id == nfsclient_accesscache_load_done_id)
+		dtrace_nfsclient_accesscache_load_done_probe = f;
+	else if (id == nfsclient_attrcache_flush_done_id)
+		dtrace_nfsclient_attrcache_flush_done_probe = f;
+	else if (id == nfsclient_attrcache_get_hit_id)
+		dtrace_nfsclient_attrcache_get_hit_probe = f;
+	else if (id == nfsclient_attrcache_get_miss_id)
+		dtrace_nfsclient_attrcache_get_miss_probe = f;
+	else if (id == nfsclient_attrcache_load_done_id)
+		dtrace_nfsclient_attrcache_load_done_probe = f;
+	else
+		*p = id;
+}
+
+static void
+dtnfsclient_disable(void *arg, dtrace_id_t id, void *parg)
+{
+	uint32_t *p = parg;
+
+	if (id == nfsclient_accesscache_flush_done_id)
+		dtrace_nfsclient_accesscache_flush_done_probe = NULL;
+	else if (id == nfsclient_accesscache_get_hit_id)
+		dtrace_nfsclient_accesscache_get_hit_probe = NULL;
+	else if (id == nfsclient_accesscache_get_miss_id)
+		dtrace_nfsclient_accesscache_get_miss_probe = NULL;
+	else if (id == nfsclient_accesscache_load_done_id)
+		dtrace_nfsclient_accesscache_load_done_probe = NULL;
+	else if (id == nfsclient_attrcache_flush_done_id)
+		dtrace_nfsclient_attrcache_flush_done_probe = NULL;
+	else if (id == nfsclient_attrcache_get_hit_id)
+		dtrace_nfsclient_attrcache_get_hit_probe = NULL;
+	else if (id == nfsclient_attrcache_get_miss_id)
+		dtrace_nfsclient_attrcache_get_miss_probe = NULL;
+	else if (id == nfsclient_attrcache_load_done_id)
+		dtrace_nfsclient_attrcache_load_done_probe = NULL;
+	else
+		*p = 0;
+}
+
+static void
+dtnfsclient_load(void *dummy)
+{
+
+	if (dtrace_register("nfsclient", &dtnfsclient_attr,
+	    DTRACE_PRIV_USER, NULL, &dtnfsclient_pops, NULL,
+	    &dtnfsclient_id) != 0)
+		return;
+
+	dtrace_nfsclient_nfs23_start_probe =
+	    (dtrace_nfsclient_nfs23_start_probe_func_t)dtrace_probe;
+	dtrace_nfsclient_nfs23_done_probe =
+	    (dtrace_nfsclient_nfs23_done_probe_func_t)dtrace_probe;
+}
+
+
+static int
+dtnfsclient_unload()
+{
+	int error = 0;
+
+	dtrace_nfsclient_nfs23_start_probe = NULL;
+	dtrace_nfsclient_nfs23_done_probe = NULL;
+
+	if ((error = dtrace_unregister(dtnfsclient_id)) != 0)
+		return (error);
+
+	return (error);
+}
+
+static int
+dtnfsclient_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);
+}
+
+SYSINIT(dtnfsclient_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY,
+    dtnfsclient_load, NULL);
+SYSUNINIT(dtnfsclient_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY,
+    dtnfsclient_unload, NULL);
+
+DEV_MODULE(dtnfsclient, dtnfsclient_modevent, NULL);
+MODULE_VERSION(dtnfsclient, 1);
+MODULE_DEPEND(dtnfsclient, dtrace, 1, 1, 1);
+MODULE_DEPEND(dtnfsclient, opensolaris, 1, 1, 1);