diff --git a/Makefile.objs b/Makefile.objs
index 804bc3c..984034a 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -344,12 +344,12 @@ else
 trace.h: trace.h-timestamp
 endif
 trace.h-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/config-host.mak
-	$(call quiet-command,sh $(SRC_PATH)/scripts/tracetool --$(TRACE_BACKEND) -h < $< > $@,"  GEN   trace.h")
+	$(call quiet-command,$(PYTHON) $(SRC_PATH)/scripts/tracetool.py --backend=$(TRACE_BACKEND) -h < $< > $@,"  GEN   trace.h")
 	@cmp -s $@ trace.h || cp $@ trace.h
 
 trace.c: trace.c-timestamp
 trace.c-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/config-host.mak
-	$(call quiet-command,sh $(SRC_PATH)/scripts/tracetool --$(TRACE_BACKEND) -c < $< > $@,"  GEN   trace.c")
+	$(call quiet-command,$(PYTHON) $(SRC_PATH)/scripts/tracetool.py --backend=$(TRACE_BACKEND) -c < $< > $@,"  GEN   trace.c")
 	@cmp -s $@ trace.c || cp $@ trace.c
 
 trace.o: trace.c $(GENERATED_HEADERS)
@@ -362,7 +362,7 @@ trace-dtrace.h: trace-dtrace.dtrace
 # rule file. So we use '.dtrace' instead
 trace-dtrace.dtrace: trace-dtrace.dtrace-timestamp
 trace-dtrace.dtrace-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/config-host.mak
-	$(call quiet-command,sh $(SRC_PATH)/scripts/tracetool --$(TRACE_BACKEND) -d < $< > $@,"  GEN   trace-dtrace.dtrace")
+	$(call quiet-command,$(PYTHON) $(SRC_PATH)/scripts/tracetool.py --backend=$(TRACE_BACKEND) -d < $< > $@,"  GEN   trace-dtrace.dtrace")
 	@cmp -s $@ trace-dtrace.dtrace || cp $@ trace-dtrace.dtrace
 
 trace-dtrace.o: trace-dtrace.dtrace $(GENERATED_HEADERS)
diff --git a/Makefile.target b/Makefile.target
index 1e90df7..07b21d1 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -50,11 +50,11 @@ TARGET_TYPE=system
 endif
 
 $(QEMU_PROG).stp:
-	$(call quiet-command,sh $(SRC_PATH)/scripts/tracetool \
-		--$(TRACE_BACKEND) \
-		--binary $(bindir)/$(QEMU_PROG) \
-		--target-arch $(TARGET_ARCH) \
-		--target-type $(TARGET_TYPE) \
+	$(call quiet-command,$(PYTHON) $(SRC_PATH)/scripts/tracetool.py \
+		--backend=$(TRACE_BACKEND) \
+		--binary=$(bindir)/$(QEMU_PROG) \
+		--target-arch=$(TARGET_ARCH) \
+		--target-type=$(TARGET_TYPE) \
 		--stap < $(SRC_PATH)/trace-events > $(QEMU_PROG).stp,"  GEN   $(QEMU_PROG).stp")
 else
 stap:
diff --git a/configure b/configure
index 19e8394..40a18d8 100755
--- a/configure
+++ b/configure
@@ -1040,7 +1040,7 @@ echo "  --disable-docs           disable documentation build"
 echo "  --disable-vhost-net      disable vhost-net acceleration support"
 echo "  --enable-vhost-net       enable vhost-net acceleration support"
 echo "  --enable-trace-backend=B Set trace backend"
-echo "                           Available backends:" $("$source_path"/scripts/tracetool --list-backends)
+echo "                           Available backends:" $("$source_path"/scripts/tracetool.py --list-backends)
 echo "  --with-trace-file=NAME   Full PATH,NAME of file to store traces"
 echo "                           Default:trace-<pid>"
 echo "  --disable-spice          disable spice"
@@ -2477,7 +2477,7 @@ fi
 ##########################################
 # check if trace backend exists
 
-sh "$source_path/scripts/tracetool" "--$trace_backend" --check-backend > /dev/null 2> /dev/null
+$python "$source_path/scripts/tracetool.py" "--backend=$trace_backend" --check-backend  > /dev/null 2> /dev/null
 if test "$?" -ne 0 ; then
   echo
   echo "Error: invalid trace backend"
@@ -2495,7 +2495,8 @@ if test "$trace_backend" = "ust"; then
 int main(void) { return 0; }
 EOF
   if compile_prog "" "" ; then
-    LIBS="-lust $LIBS"
+    LIBS="-lust -lurcu-bp $LIBS"
+    libs_qga+="-lust -lurcu-bp"
   else
     echo
     echo "Error: Trace backend 'ust' missing libust header files"
diff --git a/scripts/tracetool b/scripts/tracetool
deleted file mode 100755
index 4c9951d..0000000
--- a/scripts/tracetool
+++ /dev/null
@@ -1,643 +0,0 @@
-#!/bin/sh
-#
-# Code generator for trace events
-#
-# Copyright IBM, Corp. 2010
-#
-# This work is licensed under the terms of the GNU GPL, version 2.  See
-# the COPYING file in the top-level directory.
-
-# Disable pathname expansion, makes processing text with '*' characters simpler
-set -f
-
-usage()
-{
-    cat >&2 <<EOF
-usage: $0 [--nop | --simple | --stderr | --ust | --dtrace] [-h | -c]
-Generate tracing code for a file on stdin.
-
-Backends:
-  --nop     Tracing disabled
-  --simple  Simple built-in backend
-  --stderr  Stderr built-in backend
-  --ust     LTTng User Space Tracing backend
-  --dtrace  DTrace/SystemTAP backend
-
-Output formats:
-  -h     Generate .h file
-  -c     Generate .c file
-  -d     Generate .d file (DTrace only)
-  --stap Generate .stp file (DTrace with SystemTAP only)
-
-Options:
-  --binary       [path]    Full path to QEMU binary
-  --target-arch  [arch]    QEMU emulator target arch
-  --target-type  [type]    QEMU emulator target type ('system' or 'user')
-  --probe-prefix [prefix]  Prefix for dtrace probe names
-                           (default: qemu-\$targettype-\$targetarch)
-
-EOF
-    exit 1
-}
-
-# Print a line without interpreting backslash escapes
-#
-# The built-in echo command may interpret backslash escapes without an option
-# to disable this behavior.
-puts()
-{
-    printf "%s\n" "$1"
-}
-
-# Get the name of a trace event
-get_name()
-{
-    local name
-    name=${1%%\(*}
-    echo "${name##* }"
-}
-
-# Get the given property of a trace event
-# 1: trace-events line
-# 2: property name
-# -> return 0 if property is present, or 1 otherwise
-has_property()
-{
-    local props prop
-    props=${1%%\(*}
-    props=${props% *}
-    for prop in $props; do
-        if [ "$prop" = "$2" ]; then
-            return 0
-        fi
-    done
-    return 1
-}
-
-# Get the argument list of a trace event, including types and names
-get_args()
-{
-    local args
-    args=${1#*\(}
-    args=${args%%\)*}
-    echo "$args"
-}
-
-# Get the argument name list of a trace event
-get_argnames()
-{
-    local nfields field name sep
-    nfields=0
-    sep="$2"
-    for field in $(get_args "$1"); do
-        nfields=$((nfields + 1))
-
-        # Drop pointer star
-        field=${field#\*}
-
-        # Only argument names have commas at the end
-        name=${field%,}
-        test "$field" = "$name" && continue
-
-        printf "%s%s " $name $sep
-    done
-
-    # Last argument name
-    if [ "$nfields" -gt 1 ]
-    then
-        printf "%s" "$name"
-    fi
-}
-
-# Get the number of arguments to a trace event
-get_argc()
-{
-    local name argc
-    argc=0
-    for name in $(get_argnames "$1", ","); do
-        argc=$((argc + 1))
-    done
-    echo $argc
-}
-
-# Get the format string including double quotes for a trace event
-get_fmt()
-{
-    puts "${1#*)}"
-}
-
-linetoh_begin_nop()
-{
-    return
-}
-
-linetoh_nop()
-{
-    local name args
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-
-    # Define an empty function for the trace event
-    cat <<EOF
-static inline void trace_$name($args)
-{
-}
-EOF
-}
-
-linetoh_end_nop()
-{
-    return
-}
-
-linetoc_begin_nop()
-{
-    return
-}
-
-linetoc_nop()
-{
-    # No need for function definitions in nop backend
-    return
-}
-
-linetoc_end_nop()
-{
-    return
-}
-
-linetoh_begin_simple()
-{
-    cat <<EOF
-#include "trace/simple.h"
-EOF
-
-    simple_event_num=0
-}
-
-cast_args_to_uint64_t()
-{
-    local arg
-    for arg in $(get_argnames "$1", ","); do
-        printf "%s" "(uint64_t)(uintptr_t)$arg"
-    done
-}
-
-linetoh_simple()
-{
-    local name args argc trace_args
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-    argc=$(get_argc "$1")
-
-    trace_args="$simple_event_num"
-    if [ "$argc" -gt 0 ]
-    then
-        trace_args="$trace_args, $(cast_args_to_uint64_t "$1")"
-    fi
-
-    cat <<EOF
-static inline void trace_$name($args)
-{
-    trace$argc($trace_args);
-}
-EOF
-
-    simple_event_num=$((simple_event_num + 1))
-}
-
-linetoh_end_simple()
-{
-    cat <<EOF
-#define NR_TRACE_EVENTS $simple_event_num
-extern TraceEvent trace_list[NR_TRACE_EVENTS];
-EOF
-}
-
-linetoc_begin_simple()
-{
-    cat <<EOF
-#include "trace.h"
-
-TraceEvent trace_list[] = {
-EOF
-    simple_event_num=0
-
-}
-
-linetoc_simple()
-{
-    local name
-    name=$(get_name "$1")
-    cat <<EOF
-{.tp_name = "$name", .state=0},
-EOF
-    simple_event_num=$((simple_event_num + 1))
-}
-
-linetoc_end_simple()
-{
-    cat <<EOF
-};
-EOF
-}
-
-#STDERR
-linetoh_begin_stderr()
-{
-    cat <<EOF
-#include <stdio.h>
-#include "trace/stderr.h"
-
-extern TraceEvent trace_list[];
-EOF
-
-    stderr_event_num=0
-}
-
-linetoh_stderr()
-{
-    local name args argnames argc fmt
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-    argnames=$(get_argnames "$1" ",")
-    argc=$(get_argc "$1")
-    fmt=$(get_fmt "$1")
-
-    if [ "$argc" -gt 0 ]; then
-        argnames=", $argnames"
-    fi
-
-    cat <<EOF
-static inline void trace_$name($args)
-{
-    if (trace_list[$stderr_event_num].state != 0) {
-        fprintf(stderr, "$name " $fmt "\n" $argnames);
-    }
-}
-EOF
-    stderr_event_num=$((stderr_event_num + 1))
-
-}
-
-linetoh_end_stderr()
-{
-    cat <<EOF
-#define NR_TRACE_EVENTS $stderr_event_num
-EOF
-}
-
-linetoc_begin_stderr()
-{
-    cat <<EOF
-#include "trace.h"
-
-TraceEvent trace_list[] = {
-EOF
-    stderr_event_num=0
-}
-
-linetoc_stderr()
-{
-    local name
-    name=$(get_name "$1")
-    cat <<EOF
-{.tp_name = "$name", .state=0},
-EOF
-    stderr_event_num=$(($stderr_event_num + 1))
-}
-
-linetoc_end_stderr()
-{
-    cat <<EOF
-};
-EOF
-}
-#END OF STDERR
-
-# Clean up after UST headers which pollute the namespace
-ust_clean_namespace() {
-    cat <<EOF
-#undef mutex_lock
-#undef mutex_unlock
-#undef inline
-#undef wmb
-EOF
-}
-
-linetoh_begin_ust()
-{
-    echo "#include <ust/tracepoint.h>"
-    ust_clean_namespace
-}
-
-linetoh_ust()
-{
-    local name args argnames
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-    argnames=$(get_argnames "$1", ",")
-
-    cat <<EOF
-DECLARE_TRACE(ust_$name, TP_PROTO($args), TP_ARGS($argnames));
-#define trace_$name trace_ust_$name
-EOF
-}
-
-linetoh_end_ust()
-{
-    return
-}
-
-linetoc_begin_ust()
-{
-    cat <<EOF
-#include <ust/marker.h>
-$(ust_clean_namespace)
-#include "trace.h"
-EOF
-}
-
-linetoc_ust()
-{
-    local name args argnames fmt
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-    argnames=$(get_argnames "$1", ",")
-    [ -z "$argnames" ] || argnames=", $argnames"
-    fmt=$(get_fmt "$1")
-
-    cat <<EOF
-DEFINE_TRACE(ust_$name);
-
-static void ust_${name}_probe($args)
-{
-    trace_mark(ust, $name, $fmt$argnames);
-}
-EOF
-
-    # Collect names for later
-    names="$names $name"
-}
-
-linetoc_end_ust()
-{
-    cat <<EOF
-static void __attribute__((constructor)) trace_init(void)
-{
-EOF
-
-    for name in $names; do
-        cat <<EOF
-    register_trace_ust_$name(ust_${name}_probe);
-EOF
-    done
-
-    echo "}"
-}
-
-linetoh_begin_dtrace()
-{
-    cat <<EOF
-#include "trace-dtrace.h"
-EOF
-}
-
-linetoh_dtrace()
-{
-    local name args argnames nameupper
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-    argnames=$(get_argnames "$1", ",")
-
-    nameupper=`echo $name | tr '[:lower:]' '[:upper:]'`
-
-    # Define an empty function for the trace event
-    cat <<EOF
-static inline void trace_$name($args) {
-    if (QEMU_${nameupper}_ENABLED()) {
-        QEMU_${nameupper}($argnames);
-    }
-}
-EOF
-}
-
-linetoh_end_dtrace()
-{
-    return
-}
-
-linetoc_begin_dtrace()
-{
-    return
-}
-
-linetoc_dtrace()
-{
-    # No need for function definitions in dtrace backend
-    return
-}
-
-linetoc_end_dtrace()
-{
-    return
-}
-
-linetod_begin_dtrace()
-{
-    cat <<EOF
-provider qemu {
-EOF
-}
-
-linetod_dtrace()
-{
-    local name args
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-
-    # DTrace provider syntax expects foo() for empty
-    # params, not foo(void)
-    if [ "$args" = "void" ]; then
-       args=""
-    fi
-
-    # Define prototype for probe arguments
-    cat <<EOF
-        probe $name($args);
-EOF
-}
-
-linetod_end_dtrace()
-{
-    cat <<EOF
-};
-EOF
-}
-
-linetostap_begin_dtrace()
-{
-    return
-}
-
-linetostap_dtrace()
-{
-    local i arg name args arglist
-    name=$(get_name "$1")
-    args=$(get_args "$1")
-    arglist=$(get_argnames "$1", "")
-
-    # Define prototype for probe arguments
-    cat <<EOF
-probe $probeprefix.$name = process("$binary").mark("$name")
-{
-EOF
-
-    i=1
-    for arg in $arglist
-    do
-        # 'limit' is a reserved keyword
-        if [ "$arg" = "limit" ]; then
-          arg="_limit"
-        fi
-        cat <<EOF
-  $arg = \$arg$i;
-EOF
-        i="$((i+1))"
-    done
-
-    cat <<EOF
-}
-EOF
-}
-
-linetostap_end_dtrace()
-{
-    return
-}
-
-# Process stdin by calling begin, line, and end functions for the backend
-convert()
-{
-    local begin process_line end str disable
-    begin="lineto$1_begin_$backend"
-    process_line="lineto$1_$backend"
-    end="lineto$1_end_$backend"
-
-    "$begin"
-
-    while read -r str; do
-        # Skip comments and empty lines
-        test -z "${str%%#*}" && continue
-
-        echo
-        # Process the line.  The nop backend handles disabled lines.
-        if has_property "$str" "disable"; then
-            "lineto$1_nop" "$str"
-        else
-            "$process_line" "$str"
-        fi
-    done
-
-    echo
-    "$end"
-}
-
-tracetoh()
-{
-    cat <<EOF
-#ifndef TRACE_H
-#define TRACE_H
-
-/* This file is autogenerated by tracetool, do not edit. */
-
-#include "qemu-common.h"
-EOF
-    convert h
-    echo "#endif /* TRACE_H */"
-}
-
-tracetoc()
-{
-    echo "/* This file is autogenerated by tracetool, do not edit. */"
-    convert c
-}
-
-tracetod()
-{
-    if [ $backend != "dtrace" ]; then
-       echo "DTrace probe generator not applicable to $backend backend"
-       exit 1
-    fi
-    echo "/* This file is autogenerated by tracetool, do not edit. */"
-    convert d
-}
-
-tracetostap()
-{
-    if [ $backend != "dtrace" ]; then
-       echo "SystemTAP tapset generator not applicable to $backend backend"
-       exit 1
-    fi
-    if [ -z "$binary" ]; then
-       echo "--binary is required for SystemTAP tapset generator"
-       exit 1
-    fi
-    if [ -z "$probeprefix" -a -z "$targettype" ]; then
-       echo "--target-type is required for SystemTAP tapset generator"
-       exit 1
-    fi
-    if [ -z "$probeprefix" -a -z "$targetarch" ]; then
-       echo "--target-arch is required for SystemTAP tapset generator"
-       exit 1
-    fi
-    if [ -z "$probeprefix" ]; then
-        probeprefix="qemu.$targettype.$targetarch";
-    fi
-    echo "/* This file is autogenerated by tracetool, do not edit. */"
-    convert stap
-}
-
-
-backend=
-output=
-binary=
-targettype=
-targetarch=
-probeprefix=
-
-
-until [ -z "$1" ]
-do
-  case "$1" in
-    "--nop" | "--simple" | "--stderr" | "--ust" | "--dtrace") backend="${1#--}" ;;
-
-    "--binary") shift ; binary="$1" ;;
-    "--target-arch") shift ; targetarch="$1" ;;
-    "--target-type") shift ; targettype="$1" ;;
-    "--probe-prefix") shift ; probeprefix="$1" ;;
-
-    "-h" | "-c" | "-d") output="${1#-}" ;;
-    "--stap") output="${1#--}" ;;
-
-    "--check-backend") exit 0 ;; # used by ./configure to test for backend
-
-    "--list-backends") # used by ./configure to list available backends
-          echo "nop simple stderr ust dtrace"
-          exit 0
-          ;;
-
-    *)
-      usage;;
-  esac
-  shift
-done
-
-if [ "$backend" = "" -o "$output" = "" ]; then
-  usage
-fi
-
-gen="traceto$output"
-"$gen"
-
-exit 0
diff --git a/scripts/tracetool.py b/scripts/tracetool.py
new file mode 100755
index 0000000..6874f66
--- /dev/null
+++ b/scripts/tracetool.py
@@ -0,0 +1,585 @@
+#!/usr/bin/env python
+# Python based tracetool script (Code generator for trace events)
+#
+# Copyright IBM, Corp. 2011
+#
+# This work is licensed under the terms of the GNU GPL, version 2.  See
+# the COPYING file in the top-level directory.
+#
+#
+
+import sys
+import getopt
+
+def usage():
+    print "Tracetool: Generate tracing code for trace events file on stdin"
+    print "Usage:"
+    print sys.argv[0], " --backend=[nop|simple|stderr|dtrace|ust] [-h|-c|-d|--stap]"
+    print '''
+Backends:
+  --nop     Tracing disabled
+  --simple  Simple built-in backend
+  --stderr  Stderr built-in backend
+  --dtrace  DTrace/SystemTAP backend
+  --ust     LTTng User Space Tracing backend
+
+Output formats:
+  -h     Generate .h file
+  -c     Generate .c file
+  -d     Generate .d file (DTrace only)
+  --stap Generate .stp file (DTrace with SystemTAP only)
+
+Options:
+  --binary       [path]    Full path to QEMU binary
+  --target-arch  [arch]    QEMU emulator target arch
+  --target-type  [type]    QEMU emulator target type ('system' or 'user')
+  --probe-prefix [prefix]  Prefix for dtrace probe names
+                           (default: qemu-targettype-targetarch)
+'''
+    sys.exit(1)
+
+def get_name(line, sep='('):
+    head, sep, tail = line.partition(sep)
+    return head
+
+def get_args(line, sep1='(', sep2=')'):
+    head, sep1, tail = line.partition(sep1)
+    args, sep2, fmt_str = tail.partition(sep2)
+    return args
+
+def get_argnames(line, sep=','):
+    nfields = 0
+    str = []
+    args = get_args(line)
+    for field in args.split():
+      nfields = nfields + 1
+      # Drop pointer star
+      type, ptr, tail = field.partition('*')
+      if type != field:
+        field = tail
+
+      name, sep, tail = field.partition(',')
+
+      if name == field:
+        continue
+      str.append(name)
+      str.append(", ")
+
+    if nfields > 1:
+      str.append(name)
+      return ''.join(str)
+    else:
+      return ''
+
+def get_argc(line):
+    argc = 0
+    argnames = get_argnames(line)
+    if argnames:
+      for name in argnames.split(','):
+        argc = argc + 1
+    return argc
+
+def get_fmt(line, sep=')'):
+    event, sep, fmt = line.partition(sep)
+    return fmt
+
+def calc_sizeofargs(line):
+    args = get_args(line)
+    argc = get_argc(line)
+    strtype = ('const char*', 'char*', 'const char *', 'char *')
+    str = []
+    newstr = ""
+    if argc > 0:
+      str = args.split(',')
+      for elem in str:
+        if elem.lstrip().startswith(strtype): #strings
+          type, sep, var = elem.rpartition('*')
+          newstr = newstr+"4 + strlen("+var.lstrip()+") + "
+        #elif '*' in elem:
+        #  newstr = newstr + "4 + " # pointer vars
+        else:
+          #type, sep, var = elem.rpartition(' ')
+          #newstr = newstr+"sizeof("+type.lstrip()+") + "
+          newstr = newstr + '8 + '
+    newstr = newstr + '0' # for last +
+    return newstr
+
+
+def trace_h_begin():
+    print '''#ifndef TRACE_H
+#define TRACE_H
+
+/* This file is autogenerated by tracetool, do not edit. */
+
+#include "qemu-common.h"'''
+    return
+
+def trace_h_end():
+    print '#endif /* TRACE_H */'
+    return
+
+def trace_c_begin():
+    print '/* This file is autogenerated by tracetool, do not edit. */'
+    return
+
+def trace_c_end():
+    # nop, required for trace_gen
+    return
+
+def nop_h(events):
+    print
+    for event in events:
+        print '''static inline void trace_%(name)s(%(args)s)
+{
+}
+''' % {
+    'name': event.name,
+    'args': event.args
+}
+    return
+
+def nop_c(events):
+    # nop, reqd for converters
+    return
+
+
+def simple_h(events):
+    print '#include "trace/simple.h"'
+    print
+    for event in events:
+        print 'void trace_%(name)s(%(args)s);' % {
+    'name': event.name,
+    'args': event.args
+}
+    print
+    print '#define NR_TRACE_EVENTS %d' % (event.num + 1)
+    print 'extern TraceEvent trace_list[NR_TRACE_EVENTS];'
+
+    return
+
+def is_string(arg):
+    strtype = ('const char*', 'char*', 'const char *', 'char *')
+    if arg.lstrip().startswith(strtype):
+        return True
+    else:
+        return False
+
+def simple_c(events):
+    rec_off = 0
+    print '#include "trace.h"'
+    print '#include "trace/simple.h"'
+    print
+    print 'TraceEvent trace_list[] = {'
+    print
+    eventlist = list(events)
+    for event in eventlist:
+        print '{.tp_name = "%(name)s", .state=0},' % {
+    'name': event.name
+}
+        print
+    print '};'
+    print
+    for event in eventlist:
+        argc = event.argc
+        print '''void trace_%(name)s(%(args)s)
+{
+    unsigned int tbuf_idx, rec_off;
+    uint64_t var64 __attribute__ ((unused));
+    uint64_t pvar64 __attribute__ ((unused));
+    uint32_t slen __attribute__ ((unused));
+
+    if (!trace_list[%(event_id)s].state) {
+        return;
+    }
+''' % {
+    'name': event.name,
+    'args': event.args,
+    'event_id': event.num,
+}
+        print '''
+    tbuf_idx = trace_alloc_record(%(event_id)s, %(sizestr)s);
+    rec_off = (tbuf_idx + ST_V2_REC_HDR_LEN) %% TRACE_BUF_LEN; /* seek record header */
+''' % {'event_id': event.num, 'sizestr': event.sizestr,}
+
+        if argc > 0:
+            str = event.arglist
+            for elem in str:
+                if is_string(elem): # if string
+                    type, sep, var = elem.rpartition('*')
+                    print '''
+    slen = strlen(%(var)s);
+    write_to_buffer(rec_off, (uint8_t*)&slen, sizeof(slen));
+    rec_off += sizeof(slen);''' % {
+    'var': var.lstrip()
+}
+                    print '''
+    write_to_buffer(rec_off, (uint8_t*)%(var)s, slen);
+    rec_off += slen;''' % {
+    'var': var.lstrip()
+}
+                elif '*' in elem: # pointer var (not string)
+                    type, sep, var = elem.rpartition('*')
+                    print '''
+    pvar64 = (uint64_t)(uint64_t*)%(var)s;
+    write_to_buffer(rec_off, (uint8_t*)&pvar64, sizeof(uint64_t));
+    rec_off += sizeof(uint64_t);''' % {
+    'var': var.lstrip()
+}
+                else: # primitive data type
+                    type, sep, var = elem.rpartition(' ')
+                    print '''
+    var64 = (uint64_t)%(var)s;
+    write_to_buffer(rec_off, (uint8_t*)&var64, sizeof(uint64_t));
+    rec_off += sizeof(uint64_t);''' % {
+    'var': var.lstrip()
+}
+        print '''
+    trace_mark_record_complete(tbuf_idx);'''
+        print '}'
+        print
+
+    return
+
+def stderr_h(events):
+    print '''#include <stdio.h>
+#include "trace/stderr.h"
+
+extern TraceEvent trace_list[];'''
+    for event in events:
+        argnames = event.argnames
+        if event.argc > 0:
+            argnames = ', ' + event.argnames
+        else:
+            argnames = ''
+        print '''
+static inline void trace_%(name)s(%(args)s)
+{
+    if (trace_list[%(event_num)s].state != 0) {
+        fprintf(stderr, "%(name)s " %(fmt)s "\\n" %(argnames)s);
+    }
+}''' % {
+    'name': event.name,
+    'args': event.args,
+    'event_num': event.num,
+    'fmt': event.fmt.rstrip('\n'),
+    'argnames': argnames
+}
+    print
+    print '#define NR_TRACE_EVENTS %d' % (event.num + 1)
+
+def stderr_c(events):
+    print '''#include "trace.h"
+
+TraceEvent trace_list[] = {
+'''
+    for event in events:
+        print '{.tp_name = "%(name)s", .state=0},' % {
+    'name': event.name
+}
+        print
+    print '};'
+
+def ust_h(events):
+    print '''#include <ust/tracepoint.h>
+#undef mutex_lock
+#undef mutex_unlock
+#undef inline
+#undef wmb'''
+
+    for event in events:
+        if event.argc > 0:
+            print '''
+DECLARE_TRACE(ust_%(name)s, TP_PROTO(%(args)s), TP_ARGS(%(argnames)s));
+#define trace_%(name)s trace_ust_%(name)s''' % {
+    'name': event.name,
+    'args': event.args,
+    'argnames': event.argnames
+}
+        else:
+            print '''
+_DECLARE_TRACEPOINT_NOARGS(ust_%(name)s);
+#define trace_%(name)s trace_ust_%(name)s''' % {
+    'name': event.name,
+}
+    print
+    return
+
+def ust_c(events):
+    print '''#include <ust/marker.h>
+#undef mutex_lock
+#undef mutex_unlock
+#undef inline
+#undef wmb
+#include "trace.h"'''
+    eventlist = list(events)
+    for event in eventlist:
+        argnames = event.argnames
+        if event.argc > 0:
+            argnames = ', ' + event.argnames
+            print '''
+DEFINE_TRACE(ust_%(name)s);
+
+static void ust_%(name)s_probe(%(args)s)
+{
+    trace_mark(ust, %(name)s, %(fmt)s%(argnames)s);
+}''' % {
+    'name': event.name,
+    'args': event.args,
+    'fmt': event.fmt.rstrip('\n'),
+    'argnames': argnames
+}
+        else:
+            print '''
+DEFINE_TRACE(ust_%(name)s);
+
+static void ust_%(name)s_probe(%(args)s)
+{
+    trace_mark(ust, %(name)s, UST_MARKER_NOARGS);
+}''' % {
+    'name': event.name,
+    'args': event.args,
+}
+
+    # register probes
+    print '''
+static void __attribute__((constructor)) trace_init(void)
+{'''
+    for event in eventlist:
+        print '    register_trace_ust_%(name)s(ust_%(name)s_probe);' % {
+    'name': event.name
+}
+    print '}'
+
+    return
+
+def dtrace_h(events):
+    print '#include "trace-dtrace.h"'
+    print
+    for event in events:
+        print '''static inline void trace_%(name)s(%(args)s) {
+    if (QEMU_%(uppername)s_ENABLED()) {
+        QEMU_%(uppername)s(%(argnames)s);
+    }
+}
+''' % {
+    'name': event.name,
+    'args': event.args,
+    'uppername': event.name.upper(),
+    'argnames': event.argnames,
+}
+
+def dtrace_c(events):
+    return # No need for function definitions in dtrace backend
+
+def dtrace_d(events):
+    print 'provider qemu {'
+    for event in events:
+        args = event.args
+
+        # DTrace provider syntax expects foo() for empty
+        # params, not foo(void)
+        if args == 'void':
+            args = ''
+
+        # Define prototype for probe arguments
+        print '''
+        probe %(name)s(%(args)s);''' % {
+        'name': event.name,
+        'args': args
+}
+    print
+    print '};'
+    return
+
+def dtrace_stp(events):
+    for event in events:
+        # Define prototype for probe arguments
+        print '''
+probe %(probeprefix)s.%(name)s = process("%(binary)s").mark("%(name)s")
+{''' % {
+    'probeprefix': probeprefix,
+    'name': event.name,
+    'binary': binary
+}
+        i = 1
+        if event.argc > 0:
+            for arg in event.argnames.split(','):
+                # 'limit' is a reserved keyword
+                if arg == 'limit':
+                    arg = '_limit'
+                print '  %s = $arg%d;' % (arg.lstrip(), i)
+                i += 1
+        print '}'
+    print
+    return
+
+def trace_stap_begin():
+    global probeprefix
+    if backend != "dtrace":
+        print 'SystemTAP tapset generator not applicable to %s backend' % backend
+        sys.exit(1)
+    if binary == "":
+        print '--binary is required for SystemTAP tapset generator'
+        sys.exit(1)
+    if ((probeprefix == "") and (targettype == "")):
+        print '--target-type is required for SystemTAP tapset generator'
+        sys.exit(1)
+    if ((probeprefix == "") and (targetarch == "")):
+        print '--target-arch is required for SystemTAP tapset generator'
+        sys.exit(1)
+    if probeprefix == "":
+        probeprefix = 'qemu.' + targettype + '.' + targetarch
+    print '/* This file is autogenerated by tracetool, do not edit. */'
+    return
+
+def trace_stap_end():
+    return #nop, reqd for trace_gen
+
+def trace_d_begin():
+    if backend != 'dtrace':
+        print 'DTrace probe generator not applicable to %s backend' % backend
+        sys.exit(1)
+    print '/* This file is autogenerated by tracetool, do not edit. */'
+
+def trace_d_end():
+    return #nop, reqd for trace_gen
+
+
+# Registry of backends and their converter functions
+converters = {
+    'simple': {
+        'h': simple_h,
+	'c': simple_c,
+    },
+
+    'nop': {
+        'h': nop_h,
+        'c': nop_c,
+    },
+
+    'stderr': {
+        'h': stderr_h,
+        'c': stderr_c,
+    },
+
+    'dtrace': {
+        'h': dtrace_h,
+        'c': dtrace_c,
+        'd': dtrace_d,
+        'stap': dtrace_stp
+    },
+
+    'ust': {
+        'h': ust_h,
+        'c': ust_c,
+    },
+
+}
+
+# Trace file header and footer code generators
+trace_gen = {
+    'h': {
+        'begin': trace_h_begin,
+        'end': trace_h_end,
+    },
+    'c': {
+        'begin': trace_c_begin,
+        'end': trace_c_end,
+    },
+    'd': {
+        'begin': trace_d_begin,
+        'end': trace_d_end,
+    },
+    'stap': {
+        'begin': trace_stap_begin,
+        'end': trace_stap_end,
+    },
+}
+
+# A trace event
+class Event(object):
+    def __init__(self, num, line):
+        self.num = num
+        self.args = get_args(line)
+        self.arglist = self.args.split(',')
+        self.name = get_name(line)
+        self.argc = get_argc(line)
+        self.argnames = get_argnames(line)
+        self.sizestr = calc_sizeofargs(line)
+        self.fmt = get_fmt(line)
+
+# Generator that yields Event objects given a trace-events file object
+def read_events(fobj):
+    event_num = 0
+    for line in fobj:
+        if not line.strip():
+            continue
+        if line.lstrip().startswith('#'):
+	    continue
+	yield Event(event_num, line)
+	event_num += 1
+
+backend = ""
+output = ""
+binary = ""
+targettype = ""
+targetarch = ""
+probeprefix = ""
+
+def main():
+    global backend, output, binary, targettype, targetarch, probeprefix
+    supported_backends = ["simple", "nop", "stderr", "dtrace", "ust"]
+    short_options = "hcd"
+    long_options = ["stap", "backend=", "binary=", "target-arch=", "target-type=", "probe-prefix=", "list-backends", "check-backend"]
+    try:
+        opts, args = getopt.getopt(sys.argv[1:], short_options, long_options)
+    except getopt.GetoptError, err:
+        # print help information and exit:
+        print str(err) # will print something like "option -a not recognized"
+        usage()
+        sys.exit(2)
+    for opt, arg in opts:
+        if opt == '-h':
+            output = 'h'
+        elif opt == '-c':
+            output = 'c'
+        elif opt == '-d':
+            output = 'd'
+        elif opt == '--stap':
+            output = 'stap'
+        elif opt == '--backend':
+            backend = arg
+        elif opt == '--binary':
+            binary = arg
+        elif opt == '--target-arch':
+            targetarch = arg
+        elif opt == '--target-type':
+            targettype = arg
+        elif opt == '--probe-prefix':
+            probeprefix = arg
+        elif opt == '--list-backends':
+            print 'simple, nop, stderr, dtrace'
+            sys.exit(0)
+        elif opt == "--check-backend":
+            if any(backend in s for s in supported_backends):
+                sys.exit(0)
+            else:
+                sys.exit(1)
+        else:
+            #assert False, "unhandled option"
+            print "unhandled option: ", opt
+            usage()
+
+    if backend == "" or output == "":
+        usage()
+        sys.exit(0)
+
+    events = read_events(sys.stdin)
+    trace_gen[output]['begin']()
+    converters[backend][output](events)
+    trace_gen[output]['end']()
+    return
+
+if __name__ == "__main__":
+    main()
+
