Fix for bug #2406 (autodetect supported relayfs versions)

12 files changed, 275 insertions, 60 deletions

diff --git a/ChangeLog b/ChangeLog
index 16c5032b..abb124db 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2006-03-15 Tom Zanussi  <zanussi@us.ibm.com>
+
+	* configure.ac: Add check for relayfs version.
+	* configure: Regenerated.
+	* stp_check.in: Remove bundled relayfs loading/compilation, add
+	check for relay (vs relayfs).
+
 2006-03-13  Josh Stone  <joshua.i.stone@intel.com>
 
 	* safety/safety.py: Support IA64 disassembly matching.
diff --git a/configure b/configure
index ad70dbc9..5c566cd0 100755
--- a/configure
+++ b/configure
@@ -310,7 +310,7 @@ ac_includes_default="\
 # include <unistd.h>
 #endif"
 
-ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA CYGPATH_W PACKAGE VERSION ACLOCAL AUTOCONF AUTOMAKE AUTOHEADER MAKEINFO install_sh STRIP ac_ct_STRIP INSTALL_STRIP_PROGRAM mkdir_p AWK SET_MAKE am__leading_dot AMTAR am__tar am__untar MAINTAINER_MODE_TRUE MAINTAINER_MODE_FALSE MAINT LN_S CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC EXEEXT OBJEXT DEPDIR am__include am__quote AMDEP_TRUE AMDEP_FALSE AMDEPBACKSLASH CCDEPMODE am__fastdepCC_TRUE am__fastdepCC_FALSE CXX CXXFLAGS ac_ct_CXX CXXDEPMODE am__fastdepCXX_TRUE am__fastdepCXX_FALSE CPP EGREP U ANSI2KNR RANLIB ac_ct_RANLIB BUILD_ELFUTILS_TRUE BUILD_ELFUTILS_FALSE stap_LIBS DATE LIBOBJS LTLIBOBJS'
+ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA CYGPATH_W PACKAGE VERSION ACLOCAL AUTOCONF AUTOMAKE AUTOHEADER MAKEINFO install_sh STRIP ac_ct_STRIP INSTALL_STRIP_PROGRAM mkdir_p AWK SET_MAKE am__leading_dot AMTAR am__tar am__untar MAINTAINER_MODE_TRUE MAINTAINER_MODE_FALSE MAINT LN_S CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC EXEEXT OBJEXT DEPDIR am__include am__quote AMDEP_TRUE AMDEP_FALSE AMDEPBACKSLASH CCDEPMODE am__fastdepCC_TRUE am__fastdepCC_FALSE CXX CXXFLAGS ac_ct_CXX CXXDEPMODE am__fastdepCXX_TRUE am__fastdepCXX_FALSE CPP EGREP U ANSI2KNR RANLIB ac_ct_RANLIB BUILD_ELFUTILS_TRUE BUILD_ELFUTILS_FALSE stap_LIBS DATE RELAYFS_VERSION_GE_4 LIBOBJS LTLIBOBJS'
 ac_subst_files=''
 
 # Initialize some variables set by options.
@@ -5203,9 +5203,41 @@ _ACEOF
 DATE="$date"
 
 
+uname_r=`uname -r`
+relayfs_version_ge_4=0
+as_ac_File=`echo "ac_cv_file_/lib/modules/$uname_r/build/include/linux/relayfs_fs.h" | $as_tr_sh`
+echo "$as_me:$LINENO: checking for /lib/modules/$uname_r/build/include/linux/relayfs_fs.h" >&5
+echo $ECHO_N "checking for /lib/modules/$uname_r/build/include/linux/relayfs_fs.h... $ECHO_C" >&6
+if eval "test \"\${$as_ac_File+set}\" = set"; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  test "$cross_compiling" = yes &&
+  { { echo "$as_me:$LINENO: error: cannot check for file existence when cross compiling" >&5
+echo "$as_me: error: cannot check for file existence when cross compiling" >&2;}
+   { (exit 1); exit 1; }; }
+if test -r "/lib/modules/$uname_r/build/include/linux/relayfs_fs.h"; then
+  eval "$as_ac_File=yes"
+else
+  eval "$as_ac_File=no"
+fi
+fi
+echo "$as_me:$LINENO: result: `eval echo '${'$as_ac_File'}'`" >&5
+echo "${ECHO_T}`eval echo '${'$as_ac_File'}'`" >&6
+if test `eval echo '${'$as_ac_File'}'` = yes; then
+
+  # grep needs the two tabs in the following line
+  if grep "RELAYFS_CHANNEL_VERSION		[456]" /lib/modules/$uname_r/build/include/linux/relayfs_fs.h >/dev/null; then
+    relayfs_version_ge_4=1
+ fi
+
+fi
+
+RELAYFS_VERSION_GE_4="$relayfs_version_ge_4"
+
+
           ac_config_headers="$ac_config_headers config.h:config.in"
 
-                                                                      ac_config_files="$ac_config_files Makefile systemtap.spec stp_check stap.1 stapprobes.5 stapfuncs.5 stapex.5"
+                                                                                ac_config_files="$ac_config_files Makefile systemtap.spec stp_check stap.1 stapprobes.5 stapfuncs.5 stapex.5 runtime/transport/relayfs-config.h"
 
 cat >confcache <<\_ACEOF
 # This file is a shell script that caches the results of configure
@@ -5791,6 +5823,7 @@ do
   "stapprobes.5" ) CONFIG_FILES="$CONFIG_FILES stapprobes.5" ;;
   "stapfuncs.5" ) CONFIG_FILES="$CONFIG_FILES stapfuncs.5" ;;
   "stapex.5" ) CONFIG_FILES="$CONFIG_FILES stapex.5" ;;
+  "runtime/transport/relayfs-config.h" ) CONFIG_FILES="$CONFIG_FILES runtime/transport/relayfs-config.h" ;;
   "depfiles" ) CONFIG_COMMANDS="$CONFIG_COMMANDS depfiles" ;;
   "config.h" ) CONFIG_HEADERS="$CONFIG_HEADERS config.h:config.in" ;;
   *) { { echo "$as_me:$LINENO: error: invalid argument: $ac_config_target" >&5
@@ -5936,6 +5969,7 @@ s,@BUILD_ELFUTILS_TRUE@,$BUILD_ELFUTILS_TRUE,;t t
 s,@BUILD_ELFUTILS_FALSE@,$BUILD_ELFUTILS_FALSE,;t t
 s,@stap_LIBS@,$stap_LIBS,;t t
 s,@DATE@,$DATE,;t t
+s,@RELAYFS_VERSION_GE_4@,$RELAYFS_VERSION_GE_4,;t t
 s,@LIBOBJS@,$LIBOBJS,;t t
 s,@LTLIBOBJS@,$LTLIBOBJS,;t t
 CEOF
diff --git a/configure.ac b/configure.ac
index 99f2916c..e593233d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -52,8 +52,19 @@ date=`date +%Y-%m-%d`
 AC_DEFINE_UNQUOTED(DATE, "$date", [Configuration/build date])
 AC_SUBST(DATE, "$date")
 
+uname_r=`uname -r`
+relayfs_version_ge_4=0
+AC_CHECK_FILE(/lib/modules/$uname_r/build/include/linux/relayfs_fs.h,
+[
+  # grep needs the two tabs in the following line
+  if grep "RELAYFS_CHANNEL_VERSION		[[456]]" /lib/modules/$uname_r/build/include/linux/relayfs_fs.h >/dev/null; then
+    relayfs_version_ge_4=1
+ fi
+])
+AC_SUBST(RELAYFS_VERSION_GE_4, "$relayfs_version_ge_4")
+
 AC_CONFIG_HEADERS([config.h:config.in])
-AC_CONFIG_FILES(Makefile systemtap.spec stp_check stap.1 stapprobes.5 stapfuncs.5 stapex.5)
+AC_CONFIG_FILES(Makefile systemtap.spec stp_check stap.1 stapprobes.5 stapfuncs.5 stapex.5 runtime/transport/relayfs-config.h)
 AC_OUTPUT
 
 if test $build_elfutils = yes; then
diff --git a/runtime/stpd/ChangeLog b/runtime/stpd/ChangeLog
index dfaf199b..8151f5be 100644
--- a/runtime/stpd/ChangeLog
+++ b/runtime/stpd/ChangeLog
@@ -1,3 +1,7 @@
+2006-03-15  Tom Zanussi  <zanussi@us.ibm.com>
+
+	* stpd.c (main): Add runtime check for relayfs vs relay-on-proc.
+
 2006-03-06  Martin Hunt  <hunt@redhat.com>
 
 	* librelay.c (start_cmd): Set proper uid/gid before execing
diff --git a/runtime/stpd/stpd.c b/runtime/stpd/stpd.c
index bb1a81e0..e99f4b47 100644
--- a/runtime/stpd/stpd.c
+++ b/runtime/stpd/stpd.c
@@ -23,8 +23,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <strings.h>
+#include <string.h>
 #include <sys/wait.h>
+#include <sys/statfs.h>
 #include <pwd.h>
 #include "librelay.h"
 
@@ -88,6 +89,7 @@ int main(int argc, char **argv)
 {
 	int c, status;
 	pid_t pid;
+	struct statfs st;
 
 	while ((c = getopt(argc, argv, "mpqrb:n:t:d:c:vo:u:")) != EOF)
 	{
@@ -210,7 +212,11 @@ int main(int argc, char **argv)
 			outfile_name = DEFAULT_OUTFILE_NAME;
 	}
 	
-	sprintf(stpd_filebase, "/mnt/relay/%d/cpu", getpid());
+	if (statfs("/mnt/relay", &st) < 0)
+		sprintf(stpd_filebase, "/proc/systemtap/stap_%d/cpu", driver_pid);
+	else
+		sprintf(stpd_filebase, "/mnt/relay/%d/cpu", getpid());
+	
 	if (init_stp(stpd_filebase, !quiet)) {
 		//fprintf(stderr, "Couldn't initialize stpd. Exiting.\n");
 		exit(1);
diff --git a/runtime/transport/ChangeLog b/runtime/transport/ChangeLog
index d3b29e37..36667ecc 100644
--- a/runtime/transport/ChangeLog
+++ b/runtime/transport/ChangeLog
@@ -1,3 +1,26 @@
+2006-03-15  Tom Zanussi  <zanussi@us.ibm.com>
+ 
+ 	* procfs.c (_stp_proc_read): Add ifdef for CONFIG_RELAY.
+ 	(_stp_get_proc_root): New function.
+ 	(_stp_force_dir_create): New function.
+ 	(_stp_register_procfs): Add support for CONFIG_RELAY files in
+ 	proc.
+ 
+ 	* relayfs.c (_stp_subbuf_start): Fix ppc64 compilation error
+ 	mentioned in bug #2406.
+ 	(_stp_create_buf_file): New function.
+ 	(_stp_remove_buf_file): New function.
+ 	(_stp_relayfs_close): Add support for CONFIG_RELAY.
+ 	(_stp_relayfs_open): Add support for CONFIG_RELAY.
+ 
+ 	* relayfs.h: Add support for CONFIG_RELAY and
+ 	RELAYFS_VERSION_GE_4.
+ 	* transport.c (_stp_handle_buf_info.c): Add support for
+ 	CONFIG_RELAY.
+ 	* transport (_stp_transport_open.c): Add support for CONFIG_RELAY.
+
+ 	* relayfs-config.h.in: New file.
+
 2006-03-15  Martin Hunt  <hunt@redhat.com>
 
 	* procfs.c (STP_DEFAULT_BUFFERS): Bump up to 256.
diff --git a/runtime/transport/procfs.c b/runtime/transport/procfs.c
index 96337466..22b14046 100644
--- a/runtime/transport/procfs.c
+++ b/runtime/transport/procfs.c
@@ -31,13 +31,13 @@ _stp_proc_read (struct file *file, char __user *buf, size_t count, loff_t *ppos)
 		return -EINVAL;
 
 	out.cpu = cpu;
-#ifdef RELAYFS_VERSION_GE_4
+#if RELAYFS_VERSION_GE_4 || defined (CONFIG_RELAY)
 	out.produced = _stp_chan->buf[cpu]->subbufs_produced;
 	out.consumed = _stp_chan->buf[cpu]->subbufs_consumed;
 #else
 	out.produced = atomic_read(&_stp_chan->buf[cpu]->subbufs_produced);
 	out.consumed = atomic_read(&_stp_chan->buf[cpu]->subbufs_consumed);
-#endif /* RELAYFS_VERSION_GE_4 */
+#endif  /* RELAYFS_VERSION_GE_4 || CONFIG_RELAY */
 
 	num = sizeof(out);
 	if (copy_to_user(buf, &out, num))
@@ -262,6 +262,38 @@ err:
 	return _stp_current_buffers;
 }
 
+#if defined (STP_RELAYFS) && defined(CONFIG_RELAY)
+struct dentry *module_dir_dentry;
+
+static inline struct dentry *_stp_get_proc_root(void)
+{
+	struct file_system_type *procfs_type;
+	struct super_block *procfs_sb;
+
+	procfs_type = get_fs_type("proc");
+	if (!procfs_type || list_empty(&procfs_type->fs_supers))
+		return NULL;
+	procfs_sb = list_entry(procfs_type->fs_supers.next,
+			       struct super_block, s_instances);
+	return procfs_sb->s_root;
+}
+
+static inline struct dentry *_stp_force_dir_creation(const char *dirname, struct dentry *parent)
+{
+	struct dentry *dir_dentry;
+
+	mutex_lock(&parent->d_inode->i_mutex);
+	dir_dentry = lookup_one_len(dirname, parent, strlen(dirname));
+	mutex_unlock(&parent->d_inode->i_mutex);
+	if (IS_ERR(dir_dentry)) {
+		dir_dentry = NULL;
+		remove_proc_entry(dirname, NULL);
+	}
+	
+	return dir_dentry;
+}
+#endif  /* STP_RELAYFS && CONFIG_RELAY */
+
 static int _stp_register_procfs (void)
 {
 	int i;
@@ -270,6 +302,10 @@ static int _stp_register_procfs (void)
 	int j;
 	char buf[8];
 #endif
+#if defined (CONFIG_RELAY)
+	struct dentry *proc_root_dentry;
+	struct dentry *systemtap_dir_dentry;
+#endif /* CONFIG_RELAY */
 	struct proc_dir_entry *de;
 	struct list_head *p, *tmp;
 
@@ -301,11 +337,23 @@ static int _stp_register_procfs (void)
 			goto err0;
 	}
 
+#if defined (STP_RELAYFS) && defined (CONFIG_RELAY)
+	proc_root_dentry = _stp_get_proc_root();
+	systemtap_dir_dentry = _stp_force_dir_creation(dirname, proc_root_dentry);
+	if (!systemtap_dir_dentry)
+		goto err0;
+#endif /* STP_RELAYFS && CONFIG_RELAY */
 	/* now create /proc/systemtap/module_name */
 	_stp_proc_mod = proc_mkdir (THIS_MODULE->name, _stp_proc_root);
 	if (_stp_proc_mod == NULL)
 		goto err0;
 
+#if defined (STP_RELAYFS) && defined (CONFIG_RELAY)
+	module_dir_dentry = _stp_force_dir_creation(THIS_MODULE->name, systemtap_dir_dentry);
+	if (!module_dir_dentry)
+		goto err0;
+#endif /* STP_RELAYFS && CONFIG_RELAY */
+
 #ifdef STP_RELAYFS	
 	/* now for each cpu "n", create /proc/systemtap/module_name/n  */
 	for_each_cpu(i) {
diff --git a/runtime/transport/relayfs-config.h.in b/runtime/transport/relayfs-config.h.in
new file mode 100644
index 00000000..57fcc053
--- /dev/null
+++ b/runtime/transport/relayfs-config.h.in
@@ -0,0 +1,2 @@
+/* relayfs version ge 4 */
+#define RELAYFS_VERSION_GE_4 @RELAYFS_VERSION_GE_4@
diff --git a/runtime/transport/relayfs.c b/runtime/transport/relayfs.c
index 0754d320..6cf240fd 100644
--- a/runtime/transport/relayfs.c
+++ b/runtime/transport/relayfs.c
@@ -20,7 +20,7 @@
 
 #include "relayfs.h"
 
-#ifdef RELAYFS_VERSION_GE_4
+#if RELAYFS_VERSION_GE_4 || defined (CONFIG_RELAY)
 
 /**
  *	_stp_subbuf_start - subbuf_start() relayfs callback implementation
@@ -28,7 +28,7 @@
 static int _stp_subbuf_start(struct rchan_buf *buf,
 			     void *subbuf,
 			     void *prev_subbuf,
-			     unsigned int prev_padding)
+			     size_t prev_padding)
 {
 	if (relay_buf_full(buf))
 		return 0;
@@ -36,7 +36,7 @@ static int _stp_subbuf_start(struct rchan_buf *buf,
 	if (prev_subbuf)
 		*((unsigned *)prev_subbuf) = prev_padding;
 
-	subbuf_start_reserve(buf, sizeof(prev_padding));
+	subbuf_start_reserve(buf, sizeof(unsigned int));
 
 	return 1;
 }
@@ -69,22 +69,83 @@ static void _stp_buf_full(struct rchan_buf *buf,
 	*((unsigned *)subbuf) = padding;
 }
 
-#endif /* RELAYFS_VERSION_GE_4 */
+#endif /* RELAYFS_VERSION_GE_4 || CONFIG_RELAY */
+
+#if defined (CONFIG_RELAY)
+static struct dentry *_stp_create_buf_file(const char *filename,
+					   struct dentry *parent,
+					   int mode,
+					   struct rchan_buf *buf,
+					   int *is_global)
+{
+	struct proc_dir_entry *pde;
+	struct dentry *dentry;
+	struct proc_dir_entry *parent_pde = NULL;
+
+	if (parent)
+		parent_pde = PDE(parent->d_inode);
+	pde = create_proc_entry(filename, S_IFREG|S_IRUSR, parent_pde);
+	if (unlikely(!pde))
+		return NULL;    
+	pde->proc_fops = &relay_file_operations;
+
+	mutex_lock(&parent->d_inode->i_mutex);
+	dentry = lookup_one_len(filename, parent, strlen(filename));
+	mutex_unlock(&parent->d_inode->i_mutex);
+	if (IS_ERR(dentry))
+		remove_proc_entry(filename, parent_pde);
+
+	dentry->d_inode->u.generic_ip = buf;
+
+	return dentry;
+}
+
+static int _stp_remove_buf_file(struct dentry *dentry)
+{
+	struct proc_dir_entry *pde = PDE(dentry->d_inode);
+	
+	remove_proc_entry(pde->name, pde->parent);
+
+	return 0;
+}
+#endif /* CONFIG_RELAY */
 
 /* relayfs callback functions */
+#if defined (CONFIG_RELAY)
+static struct rchan_callbacks stp_rchan_callbacks =
+{
+	.subbuf_start = _stp_subbuf_start,
+	.create_buf_file = _stp_create_buf_file,
+	.remove_buf_file = _stp_remove_buf_file,
+};
+#else
 static struct rchan_callbacks stp_rchan_callbacks =
 {
 	.subbuf_start = _stp_subbuf_start,
-#ifndef RELAYFS_VERSION_GE_4
+#if !RELAYFS_VERSION_GE_4
 	.buf_full = _stp_buf_full,
-#endif /* RELAYFS_VERSION_GE_4 */
+#endif  /* !RELAYFS_VERSION_GE_4 */
 };
+#endif  /* CONFIG_RELAY */
 
 /**
  *	_stp_relayfs_close - destroys relayfs channel
  *	@chan: the relayfs channel
  *	@dir: the directory containing the relayfs files
  */
+#if defined (CONFIG_RELAY)
+void _stp_relayfs_close(struct rchan *chan, struct dentry *dir)
+{
+	if (!chan)
+		return;
+
+	relay_close(chan);
+	if (dir) {
+		struct proc_dir_entry *pde = PDE(dir->d_inode);
+		remove_proc_entry(pde->name, pde->parent);
+	}
+}
+#else
 void _stp_relayfs_close(struct rchan *chan, struct dentry *dir)
 {
 	if (!chan)
@@ -94,6 +155,7 @@ void _stp_relayfs_close(struct rchan *chan, struct dentry *dir)
 	if (dir)
 		relayfs_remove_dir(dir);
 }
+#endif /* CONFIG_RELAY */
 
 /**
  *	_stp_relayfs_open - create relayfs channel
@@ -101,11 +163,38 @@ void _stp_relayfs_close(struct rchan *chan, struct dentry *dir)
  *	@subbuf_size: size of relayfs sub-buffers
  *	@pid: daemon pid
  *	@outdir: receives directory dentry
+ *	@parentdir: parent directory dentry
  *
  *	Returns relay channel, NULL on failure
  *
  *	Creates relayfs files as /systemtap/pid/cpuX in relayfs root
  */
+#if defined (CONFIG_RELAY)
+extern struct dentry *module_dentry;
+struct rchan *_stp_relayfs_open(unsigned n_subbufs,
+				unsigned subbuf_size,
+				int pid,
+				struct dentry **outdir,
+				struct dentry *parent_dir)
+{
+	char dirname[16];
+	struct rchan *chan;
+	struct dentry* dir = NULL;
+
+	sprintf(dirname, "%d", pid);
+	
+	/* TODO: need to create systemtap dir */
+	chan = relay_open("cpu", parent_dir, subbuf_size,
+			  n_subbufs, &stp_rchan_callbacks);
+	if (!chan) {
+		printk("STP: couldn't create relayfs channel.\n");
+		if (dir)
+			remove_proc_entry(dirname, NULL);
+	}
+	*outdir = dir;
+	return chan;
+}
+#else
 struct rchan *_stp_relayfs_open(unsigned n_subbufs,
 				unsigned subbuf_size,
 				int pid,
@@ -124,7 +213,7 @@ struct rchan *_stp_relayfs_open(unsigned n_subbufs,
 		return NULL;
 	}
 
-#ifdef RELAYFS_VERSION_GE_4
+#if RELAYFS_VERSION_GE_4
 	chan = relay_open("cpu", dir, subbuf_size,
 			  n_subbufs, &stp_rchan_callbacks);
 #else
@@ -141,6 +230,7 @@ struct rchan *_stp_relayfs_open(unsigned n_subbufs,
 	*outdir = dir;
 	return chan;
 }
+#endif /* CONFIG_RELAY */
 
 #endif /* _TRANSPORT_RELAYFS_C_ */
 
diff --git a/runtime/transport/relayfs.h b/runtime/transport/relayfs.h
index 5ca174e4..aafb26b2 100644
--- a/runtime/transport/relayfs.h
+++ b/runtime/transport/relayfs.h
@@ -5,16 +5,30 @@
  * @brief Header file for relayfs transport
  */
 
-#ifdef RELAYFS_VERSION_GE_4
-#include <linux/relayfs_fs.h>
+#include "relayfs-config.h"
+
+#if defined (CONFIG_RELAYFS_FS) || defined (CONFIG_RELAYFS_FS_MODULE)
+#  include <linux/relayfs_fs.h>
+#elif defined (CONFIG_RELAY)
+#  include <linux/relay.h>
+#  include <linux/namei.h>
 #else
-#include "../relayfs/linux/relayfs_fs.h"
-#endif /* RELAYFS_VERSION_GE_4 */
+#  undef STP_RELAYFS
+#endif
 
+#if defined (CONFIG_RELAY)
+struct rchan *_stp_relayfs_open(unsigned n_subbufs,
+				unsigned subbuf_size,
+				int pid,
+				struct dentry **outdir,
+				struct dentry *parent_dir);
+#else
 struct rchan *_stp_relayfs_open(unsigned n_subbufs,
 				unsigned subbuf_size,
 				int pid,
 				struct dentry **outdir);
+#endif
+
 void _stp_relayfs_close(struct rchan *chan, struct dentry *dir);
 
 #endif /* _TRANSPORT_RELAYFS_H_ */
diff --git a/runtime/transport/transport.c b/runtime/transport/transport.c
index a38d1f56..01bab497 100644
--- a/runtime/transport/transport.c
+++ b/runtime/transport/transport.c
@@ -82,13 +82,13 @@ static void _stp_handle_buf_info(int *cpuptr)
 	struct buf_info out;
 
 	out.cpu = *cpuptr;
-#ifdef RELAYFS_VERSION_GE_4
+#if RELAYFS_VERSION_GE_4 || defined (CONFIG_RELAY)
 	out.produced = _stp_chan->buf[*cpuptr]->subbufs_produced;
 	out.consumed = _stp_chan->buf[*cpuptr]->subbufs_consumed;
 #else
 	out.produced = atomic_read(&_stp_chan->buf[*cpuptr]->subbufs_produced);
 	out.consumed = atomic_read(&_stp_chan->buf[*cpuptr]->subbufs_consumed);
-#endif /* RELAYFS_VERSION_GE_4 */
+#endif /* RELAYFS_VERSION_GE_4 || CONFIG_RELAY */
 
 	_stp_transport_send(STP_BUF_INFO, &out, sizeof(out));
 }
@@ -190,6 +190,10 @@ void _stp_transport_close()
 	kbug("---- CLOSED ----\n");
 }
 
+#if defined (STP_RELAYFS) && defined (CONFIG_RELAY)
+extern struct dentry *module_dir_dentry;
+#endif /* STP_RELAYFS && CONFIG_RELAY */
+
 /**
  *	_stp_transport_open - open proc and relayfs channels
  *      with proper parameters
@@ -223,7 +227,11 @@ int _stp_transport_open(struct transport_info *info)
 		info->n_subbufs = n_subbufs;
 		info->subbuf_size = subbuf_size;
 
+#if defined (CONFIG_RELAY)
+		_stp_chan = _stp_relayfs_open(n_subbufs, subbuf_size, _stp_pid, &_stp_dir, module_dir_dentry);
+#else
 		_stp_chan = _stp_relayfs_open(n_subbufs, subbuf_size, _stp_pid, &_stp_dir);
+#endif /* CONFIG_RELAY */
 		if (!_stp_chan) {
 			_stp_unregister_procfs();
 			return -ENOMEM;
diff --git a/stp_check.in b/stp_check.in
index defc0a62..6e429b91 100755
--- a/stp_check.in
+++ b/stp_check.in
@@ -1,46 +1,9 @@
 #!/bin/bash
 
-load_module()
-{
-    ret=1
-    if [ -e "$MODULE" ]
-    then
-	/sbin/insmod $MODULE
-	ret=$?
-    fi
-	
-    if [ "$ret" -ne 0 ]
-    then
-	echo "$MODULE_NAME not in kernel and not built.  Compiling..."
-	mkdir -p $MODULE_DIR
-	cp -dpr $SRC_DIR/* $MODULE_DIR
-	make -w -C $MODULE_DIR
-	if [ "$?" -ne 0 ]
-	then
-	    echo "Failed to load module $MODULE_NAME."
-	    exit $?
-	fi
-
-	/sbin/insmod $MODULE
-	if [ "$?" -ne 0 ]
-	then
-	    echo "Failed to load module $MODULE_NAME."
-	    exit $?
-	fi
-    fi
-}
-
-prefix=@prefix@
-VAR_DIR=@localstatedir@/cache/systemtap
-
-RELAYFS=`grep relayfs /proc/filesystems`
-if [ -z "$RELAYFS" ]
+RELAY=`grep sysfs_create_relay_file /proc/kallsyms`
+if [ -n "$RELAY" ]
 then
-	MODULE_NAME=relayfs
-	MODULE_DIR=$VAR_DIR/relayfs
-	MODULE=$MODULE_DIR/relayfs.ko
-	SRC_DIR=@datadir@/systemtap/runtime/relayfs
-	load_module
+	exit 0
 fi
 
 if [ ! -d "/mnt/relay" ]
@@ -54,3 +17,8 @@ then
 	mount -t relayfs relayfs /mnt/relay
 fi
 
+RELAYFS_FS=`grep relayfs /proc/kallsyms`
+if [ -z "$RELAYFS_FS" ]
+then
+	exit 1
+fi