Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

# gpg: Signature made Fri 21 Apr 2017 10:52:18 BST
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  simpletrace: document Analyzer method signatures
  trace: Put all trace.o into libqemuutil.a
  configure: eliminate Python dependency for --help

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

5 files changed, 47 insertions, 24 deletions

diff --git a/Makefile b/Makefile
index 6c359b2f86..31d41a7eae 100644
--- a/Makefile
+++ b/Makefile
@@ -346,7 +346,7 @@ dtc/%:
 	mkdir -p $@
 
 $(SUBDIR_RULES): libqemuutil.a libqemustub.a $(common-obj-y) $(chardev-obj-y) \
-	$(qom-obj-y) $(crypto-aes-obj-$(CONFIG_USER_ONLY)) $(trace-obj-y)
+	$(qom-obj-y) $(crypto-aes-obj-$(CONFIG_USER_ONLY))
 
 ROMSUBDIR_RULES=$(patsubst %,romsubdir-%, $(ROMS))
 # Only keep -O and -g cflags
@@ -366,11 +366,11 @@ Makefile: $(version-obj-y)
 # Build libraries
 
 libqemustub.a: $(stub-obj-y)
-libqemuutil.a: $(util-obj-y)
+libqemuutil.a: $(util-obj-y) $(trace-obj-y)
 
 ######################################################################
 
-COMMON_LDADDS = $(trace-obj-y) libqemuutil.a libqemustub.a
+COMMON_LDADDS = libqemuutil.a libqemustub.a
 
 qemu-img.o: qemu-img-cmds.h
 
diff --git a/Makefile.target b/Makefile.target
index 7df2b8c149..e62021d5aa 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -188,8 +188,7 @@ dummy := $(call unnest-vars,.., \
                qom-obj-y \
                io-obj-y \
                common-obj-y \
-               common-obj-m \
-               trace-obj-y)
+               common-obj-m)
 target-obj-y := $(target-obj-y-save)
 all-obj-y += $(common-obj-y)
 all-obj-y += $(target-obj-y)
@@ -201,7 +200,7 @@ all-obj-$(CONFIG_SOFTMMU) += $(io-obj-y)
 
 $(QEMU_PROG_BUILD): config-devices.mak
 
-COMMON_LDADDS = $(trace-obj-y) ../libqemuutil.a ../libqemustub.a
+COMMON_LDADDS = ../libqemuutil.a ../libqemustub.a
 
 # build either PROG or PROGW
 $(QEMU_PROG_BUILD): $(all-obj-y) $(COMMON_LDADDS)
diff --git a/configure b/configure
index be4d326ae0..6db3044fb0 100755
--- a/configure
+++ b/configure
@@ -1191,21 +1191,6 @@ for opt do
   esac
 done
 
-if ! has $python; then
-  error_exit "Python not found. Use --python=/path/to/python"
-fi
-
-# Note that if the Python conditional here evaluates True we will exit
-# with status 1 which is a shell 'false' value.
-if ! $python -c 'import sys; sys.exit(sys.version_info < (2,6) or sys.version_info >= (3,))'; then
-  error_exit "Cannot use '$python', Python 2.6 or later is required." \
-      "Note that Python 3 or later is not yet supported." \
-      "Use --python=/path/to/python to specify a supported Python."
-fi
-
-# Suppress writing compiled files
-python="$python -B"
-
 case "$cpu" in
     ppc)
            CPU_CFLAGS="-m32"
@@ -1280,6 +1265,9 @@ for config in $mak_wilds; do
     default_target_list="${default_target_list} $(basename "$config" .mak)"
 done
 
+# Enumerate public trace backends for --help output
+trace_backend_list=$(echo $(grep -le '^PUBLIC = True$' scripts/tracetool/backend/*.py | sed -e 's/^.*\/\(.*\)\.py$/\1/'))
+
 if test x"$show_help" = x"yes" ; then
 cat << EOF
 
@@ -1333,7 +1321,7 @@ Advanced options (experts only):
                            set block driver read-only whitelist
                            (affects only QEMU, not qemu-img)
   --enable-trace-backends=B Set trace backend
-                           Available backends: $($python $source_path/scripts/tracetool.py --list-backends)
+                           Available backends: $trace_backend_list
   --with-trace-file=NAME   Full PATH,NAME of file to store traces
                            Default:trace-<pid>
   --disable-slirp          disable SLIRP userspace network connectivity
@@ -1433,6 +1421,21 @@ EOF
 exit 0
 fi
 
+if ! has $python; then
+  error_exit "Python not found. Use --python=/path/to/python"
+fi
+
+# Note that if the Python conditional here evaluates True we will exit
+# with status 1 which is a shell 'false' value.
+if ! $python -c 'import sys; sys.exit(sys.version_info < (2,6) or sys.version_info >= (3,))'; then
+  error_exit "Cannot use '$python', Python 2.6 or later is required." \
+      "Note that Python 3 or later is not yet supported." \
+      "Use --python=/path/to/python to specify a supported Python."
+fi
+
+# Suppress writing compiled files
+python="$python -B"
+
 # Now we have handled --enable-tcg-interpreter and know we're not just
 # printing the help message, bail out if the host CPU isn't supported.
 if test "$ARCH" = "unknown"; then
diff --git a/scripts/simpletrace.py b/scripts/simpletrace.py
index 4c990047b6..d60b3a08f7 100755
--- a/scripts/simpletrace.py
+++ b/scripts/simpletrace.py
@@ -116,7 +116,28 @@ class Analyzer(object):
     is invoked.
 
     If a method matching a trace event name exists, it is invoked to process
-    that trace record.  Otherwise the catchall() method is invoked."""
+    that trace record.  Otherwise the catchall() method is invoked.
+
+    Example:
+    The following method handles the runstate_set(int new_state) trace event::
+
+      def runstate_set(self, new_state):
+          ...
+
+    The method can also take a timestamp argument before the trace event
+    arguments::
+
+      def runstate_set(self, timestamp, new_state):
+          ...
+
+    Timestamps have the uint64_t type and are in nanoseconds.
+
+    The pid can be included in addition to the timestamp and is useful when
+    dealing with traces from multiple processes::
+
+      def runstate_set(self, timestamp, pid, new_state):
+          ...
+    """
 
     def begin(self):
         """Called at the start of the trace."""
diff --git a/tests/Makefile.include b/tests/Makefile.include
index f3de81fcfb..579ec07cce 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -519,7 +519,7 @@ QEMU_CFLAGS += -I$(SRC_PATH)/tests
 
 
 # Deps that are common to various different sets of tests below
-test-util-obj-y = $(trace-obj-y) libqemuutil.a libqemustub.a
+test-util-obj-y = libqemuutil.a libqemustub.a
 test-qom-obj-y = $(qom-obj-y) $(test-util-obj-y)
 test-qapi-obj-y = tests/test-qapi-visit.o tests/test-qapi-types.o \
 	tests/test-qapi-event.o tests/test-qmp-introspect.o \