From patchwork Tue May 25 10:24:10 2010
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
X-Patchwork-Id: 102154
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o4PAOgkP003141
	for <patchwork-kvm@patchwork.kernel.org>;
	Tue, 25 May 2010 10:24:42 GMT
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1757053Ab0EYKYj (ORCPT
	<rfc822;patchwork-kvm@patchwork.kernel.org>);
	Tue, 25 May 2010 06:24:39 -0400
Received: from mtagate1.de.ibm.com ([195.212.17.161]:52835 "EHLO
	mtagate1.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1756575Ab0EYKYg (ORCPT <rfc822; kvm@vger.kernel.org>);
	Tue, 25 May 2010 06:24:36 -0400
Received: from d12nrmr1607.megacenter.de.ibm.com
	(d12nrmr1607.megacenter.de.ibm.com [9.149.167.49])
	by mtagate1.de.ibm.com (8.13.1/8.13.1) with ESMTP id o4PAOZLm003662
	for <kvm@vger.kernel.org>; Tue, 25 May 2010 10:24:35 GMT
Received: from d12av01.megacenter.de.ibm.com (d12av01.megacenter.de.ibm.com
	[9.149.165.212])
	by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v10.0) with
	ESMTP id o4PAOY8Y909318
	for <kvm@vger.kernel.org>; Tue, 25 May 2010 12:24:34 +0200
Received: from d12av01.megacenter.de.ibm.com (loopback [127.0.0.1])
	by d12av01.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP
	id o4PAOXw3008987
	for <kvm@vger.kernel.org>; Tue, 25 May 2010 12:24:34 +0200
Received: from stefan-thinkpad.manchester-maybrook.uk.ibm.com
	(dyn-9-174-219-32.manchester-maybrook.uk.ibm.com [9.174.219.32])
	by d12av01.megacenter.de.ibm.com (8.12.11.20060308/8.12.11) with
	ESMTP id o4PAOX0c008947; Tue, 25 May 2010 12:24:33 +0200
From: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
To: <qemu-devel@nongnu.org>, <kvm@vger.kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>,
	Prerna Saxena <prerna@linux.vnet.ibm.com>,
	Anthony Liguori <aliguori@us.ibm.com>, Avi Kivity <avi@redhat.com>,
	Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Subject: [PATCH 1/7] trace: Add trace-events file for declaring trace events
Date: Tue, 25 May 2010 11:24:10 +0100
Message-Id: <1274783056-14759-2-git-send-email-stefanha@linux.vnet.ibm.com>
X-Mailer: git-send-email 1.7.1
In-Reply-To: <1274783056-14759-1-git-send-email-stefanha@linux.vnet.ibm.com>
References: <1274783056-14759-1-git-send-email-stefanha@linux.vnet.ibm.com>
Sender: kvm-owner@vger.kernel.org
Precedence: bulk
List-ID: <kvm.vger.kernel.org>
X-Mailing-List: kvm@vger.kernel.org
X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by
	milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]);
	Tue, 25 May 2010 10:24:42 +0000 (UTC)


diff --git a/.gitignore b/.gitignore
index fdfe2f0..4644557 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,8 @@ config-devices.*
 config-all-devices.*
 config-host.*
 config-target.*
+trace.h
+trace.c
 *-softmmu
 *-darwin-user
 *-linux-user
diff --git a/Makefile b/Makefile
index 7986bf6..a9f79a9 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 # Makefile for QEMU.
 
-GENERATED_HEADERS = config-host.h
+GENERATED_HEADERS = config-host.h trace.h
 
 ifneq ($(wildcard config-host.mak),)
 # Put the all: rule here so that config-host.mak can contain dependencies.
@@ -130,16 +130,24 @@ bt-host.o: QEMU_CFLAGS += $(BLUEZ_CFLAGS)
 
 iov.o: iov.c iov.h
 
+trace.h: trace-events
+	$(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -h < $< > $@,"  GEN   $@")
+
+trace.c: trace-events
+	$(call quiet-command,sh $(SRC_PATH)/tracetool --$(TRACE_BACKEND) -c < $< > $@,"  GEN   $@")
+
+trace.o: trace.c
+
 ######################################################################
 
 qemu-img.o: qemu-img-cmds.h
 qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o: $(GENERATED_HEADERS)
 
-qemu-img$(EXESUF): qemu-img.o qemu-tool.o qemu-error.o $(block-obj-y) $(qobject-obj-y)
+qemu-img$(EXESUF): qemu-img.o qemu-tool.o qemu-error.o $(trace-obj-y) $(block-obj-y) $(qobject-obj-y)
 
-qemu-nbd$(EXESUF): qemu-nbd.o qemu-tool.o qemu-error.o $(block-obj-y) $(qobject-obj-y)
+qemu-nbd$(EXESUF): qemu-nbd.o qemu-tool.o qemu-error.o $(trace-obj-y) $(block-obj-y) $(qobject-obj-y)
 
-qemu-io$(EXESUF): qemu-io.o cmd.o qemu-tool.o qemu-error.o $(block-obj-y) $(qobject-obj-y)
+qemu-io$(EXESUF): qemu-io.o cmd.o qemu-tool.o qemu-error.o $(trace-obj-y) $(block-obj-y) $(qobject-obj-y)
 
 qemu-img-cmds.h: $(SRC_PATH)/qemu-img-cmds.hx
 	$(call quiet-command,sh $(SRC_PATH)/hxtool -h < $< > $@,"  GEN   $@")
@@ -157,6 +165,7 @@ clean:
 	rm -f *.o *.d *.a $(TOOLS) TAGS cscope.* *.pod *~ */*~
 	rm -f slirp/*.o slirp/*.d audio/*.o audio/*.d block/*.o block/*.d net/*.o net/*.d
 	rm -f qemu-img-cmds.h
+	rm -f trace.c trace.h
 	$(MAKE) -C tests clean
 	for d in $(ALL_SUBDIRS) libhw32 libhw64 libuser libdis libdis-user; do \
 	if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \
diff --git a/Makefile.objs b/Makefile.objs
index 1a942e5..20e709e 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -251,6 +251,11 @@ libdis-$(CONFIG_S390_DIS) += s390-dis.o
 libdis-$(CONFIG_SH4_DIS) += sh4-dis.o
 libdis-$(CONFIG_SPARC_DIS) += sparc-dis.o
 
+######################################################################
+# trace
+
+trace-obj-y = trace.o
+
 vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
 
 vl.o: QEMU_CFLAGS+=$(SDL_CFLAGS)
diff --git a/Makefile.target b/Makefile.target
index fda5bf3..8f7b564 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -293,6 +293,7 @@ $(obj-y) $(obj-$(TARGET_BASE_ARCH)-y): $(GENERATED_HEADERS)
 
 obj-y += $(addprefix ../, $(common-obj-y))
 obj-y += $(addprefix ../libdis/, $(libdis-y))
+obj-y += $(addprefix ../, $(trace-obj-y))
 obj-y += $(libobj-y)
 obj-y += $(addprefix $(HWDIR)/, $(hw-obj-y))
 
diff --git a/configure b/configure
index 3cd2c5f..e94e113 100755
--- a/configure
+++ b/configure
@@ -299,6 +299,7 @@ pkgversion=""
 check_utests="no"
 user_pie="no"
 zero_malloc=""
+trace_backend="nop"
 
 # OS specific
 if check_define __linux__ ; then
@@ -494,6 +495,8 @@ for opt do
   ;;
   --target-list=*) target_list="$optarg"
   ;;
+  --trace-backend=*) trace_backend="$optarg"
+  ;;
   --enable-gprof) gprof="yes"
   ;;
   --static)
@@ -826,6 +829,7 @@ echo "  --enable-docs            enable documentation build"
 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 "  --trace-backend=B        Trace backend nop"
 echo ""
 echo "NOTE: The object files are built at the place where configure is launched"
 exit 1
@@ -1914,6 +1918,18 @@ if compile_prog "" "" ; then
     fdatasync=yes
 fi
 
+##########################################
+# check if trace backend exists
+
+sh "$source_path/tracetool" "--$trace_backend" --check-backend > /dev/null 2> /dev/null
+if test "$?" -ne 0 ; then
+  echo
+  echo "Error: invalid trace backend"
+  echo "Please choose a supported trace backend."
+  echo
+  exit 1
+fi
+
 # End of CC checks
 # After here, no more $cc or $ld runs
 
@@ -2041,6 +2057,7 @@ echo "preadv support    $preadv"
 echo "fdatasync         $fdatasync"
 echo "uuid support      $uuid"
 echo "vhost-net support $vhost_net"
+echo "Trace backend     $trace_backend"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -2284,6 +2301,8 @@ bsd)
 ;;
 esac
 
+echo "TRACE_BACKEND=$trace_backend" >> $config_host_mak
+
 tools=
 if test `expr "$target_list" : ".*softmmu.*"` != 0 ; then
   tools="qemu-img\$(EXESUF) qemu-io\$(EXESUF) $tools"
diff --git a/trace-events b/trace-events
new file mode 100644
index 0000000..a37d3cc
--- /dev/null
+++ b/trace-events
@@ -0,0 +1,24 @@
+# Trace events for debugging and performance instrumentation
+#
+# This file is processed by the tracetool script during the build.
+#
+# To add a new trace event:
+#
+# 1. Choose a name for the trace event.  Declare its arguments and format
+#    string.
+#
+# 2. Call the trace event from code using trace_##name, e.g. multiwrite_cb() ->
+#    trace_multiwrite_cb().  The source file must #include "trace.h".
+#
+# Format of a trace event:
+#
+# <name>(<type1> <arg1>[, <type2> <arg2>] ...) "<format-string>"
+#
+# Example: qemu_malloc(size_t size) "size %zu"
+#
+# The <name> must be a valid as a C function name.
+#
+# Types should be standard C types.  Use void * for pointers because the trace
+# system may not have the necessary headers included.
+#
+# The <format-string> should be a sprintf()-compatible format string.
diff --git a/tracetool b/tracetool
new file mode 100755
index 0000000..766a9ba
--- /dev/null
+++ b/tracetool
@@ -0,0 +1,165 @@
+#!/bin/sh
+
+usage()
+{
+    cat >&2 <<EOF
+usage: $0 --nop [-h | -c]
+Generate tracing code for a file on stdin.
+
+Backends:
+  --nop Tracing disabled
+
+Output formats:
+  -h    Generate .h file
+  -c    Generate .c file
+EOF
+    exit 1
+}
+
+# Get the name of a trace event
+get_name()
+{
+    echo ${1%%(*}
+}
+
+# Get the argument list of a trace event, including types and names
+get_args()
+{
+    local args
+    args=${1#*(}
+    args=${args%)*}
+    echo "$args"
+}
+
+# Get the argument name list of a trace event
+get_argnames()
+{
+    local first field name
+    for field in $(get_args "$1"); do
+        # Drop pointer star
+        field=${field#\*}
+
+        # Only argument names have commas at the end
+        name=${field%,}
+        test "$field" = "$name" && continue
+
+        echo -n "$name, "
+    done
+    echo -n "$name"
+}
+
+# Get the format string for a trace event
+get_fmt()
+{
+    local fmt
+    fmt=${1#*\"}
+    fmt=${fmt%\"*}
+    echo "$fmt"
+}
+
+warn_autogen_c()
+{
+    echo "/* This file is autogenerated by tracetool, do not edit. */"
+}
+
+warn_autogen_h()
+{
+    echo "/* This file is autogenerated by tracetool, do not edit. */"
+}
+
+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
+}
+
+# Process stdin by calling begin, line, and end functions for the backend
+convert()
+{
+    local begin process_line end
+    begin="lineto$1_begin_$backend"
+    process_line="lineto$1_$backend"
+    end="lineto$1_end_$backend"
+
+    warn_autogen_$1
+    "$begin"
+
+    while read -r str; do
+        # Skip comments and empty lines
+        str=${str%%#*}
+        test -z "$str" && continue
+
+        echo
+        "$process_line" "$str"
+    done
+
+    echo
+    "$end"
+}
+
+tracetoh()
+{
+    cat <<EOF
+#ifndef TRACE_H
+#define TRACE_H
+
+#include "qemu-common.h"
+EOF
+    convert h
+    echo "#endif /* TRACE_H */"
+}
+
+tracetoc()
+{
+    convert c
+}
+
+# Choose backend
+case "$1" in
+"--nop") backend="${1#--}" ;;
+*) usage ;;
+esac
+shift
+
+case "$1" in
+"-h") tracetoh ;;
+"-c") tracetoc ;;
+"--check-backend") exit 0 ;; # used by ./configure to test for backend
+*) usage ;;
+esac
+
+exit 0