1 files changed, 263 insertions, 0 deletions
diff --git a/scripts/simpletrace.py b/scripts/simpletrace.py
new file mode 100755
index 000000000..1f6d1ae1f
--- /dev/null
+++ b/scripts/simpletrace.py
@@ -0,0 +1,263 @@
+#!/usr/bin/env python3
+#
+# Pretty-printer for simple trace backend binary trace files
+#
+# 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.
+#
+# For help see docs/devel/tracing.rst
+
+import struct
+import inspect
+from tracetool import read_events, Event
+from tracetool.backend.simple import is_string
+
+header_event_id = 0xffffffffffffffff
+header_magic    = 0xf2b177cb0aa429b4
+dropped_event_id = 0xfffffffffffffffe
+
+record_type_mapping = 0
+record_type_event = 1
+
+log_header_fmt = '=QQQ'
+rec_header_fmt = '=QQII'
+
+def read_header(fobj, hfmt):
+    '''Read a trace record header'''
+    hlen = struct.calcsize(hfmt)
+    hdr = fobj.read(hlen)
+    if len(hdr) != hlen:
+        return None
+    return struct.unpack(hfmt, hdr)
+
+def get_record(edict, idtoname, rechdr, fobj):
+    """Deserialize a trace record from a file into a tuple
+       (name, timestamp, pid, arg1, ..., arg6)."""
+    if rechdr is None:
+        return None
+    if rechdr[0] != dropped_event_id:
+        event_id = rechdr[0]
+        name = idtoname[event_id]
+        rec = (name, rechdr[1], rechdr[3])
+        try:
+            event = edict[name]
+        except KeyError as e:
+            import sys
+            sys.stderr.write('%s event is logged but is not declared ' \
+                             'in the trace events file, try using ' \
+                             'trace-events-all instead.\n' % str(e))
+            sys.exit(1)
+
+        for type, name in event.args:
+            if is_string(type):
+                l = fobj.read(4)
+                (len,) = struct.unpack('=L', l)
+                s = fobj.read(len)
+                rec = rec + (s,)
+            else:
+                (value,) = struct.unpack('=Q', fobj.read(8))
+                rec = rec + (value,)
+    else:
+        rec = ("dropped", rechdr[1], rechdr[3])
+        (value,) = struct.unpack('=Q', fobj.read(8))
+        rec = rec + (value,)
+    return rec
+
+def get_mapping(fobj):
+    (event_id, ) = struct.unpack('=Q', fobj.read(8))
+    (len, ) = struct.unpack('=L', fobj.read(4))
+    name = fobj.read(len).decode()
+
+    return (event_id, name)
+
+def read_record(edict, idtoname, fobj):
+    """Deserialize a trace record from a file into a tuple (event_num, timestamp, pid, arg1, ..., arg6)."""
+    rechdr = read_header(fobj, rec_header_fmt)
+    return get_record(edict, idtoname, rechdr, fobj)
+
+def read_trace_header(fobj):
+    """Read and verify trace file header"""
+    header = read_header(fobj, log_header_fmt)
+    if header is None:
+        raise ValueError('Not a valid trace file!')
+    if header[0] != header_event_id:
+        raise ValueError('Not a valid trace file, header id %d != %d' %
+                         (header[0], header_event_id))
+    if header[1] != header_magic:
+        raise ValueError('Not a valid trace file, header magic %d != %d' %
+                         (header[1], header_magic))
+
+    log_version = header[2]
+    if log_version not in [0, 2, 3, 4]:
+        raise ValueError('Unknown version of tracelog format!')
+    if log_version != 4:
+        raise ValueError('Log format %d not supported with this QEMU release!'
+                         % log_version)
+
+def read_trace_records(edict, idtoname, fobj):
+    """Deserialize trace records from a file, yielding record tuples (event_num, timestamp, pid, arg1, ..., arg6).
+
+    Note that `idtoname` is modified if the file contains mapping records.
+
+    Args:
+        edict (str -> Event): events dict, indexed by name
+        idtoname (int -> str): event names dict, indexed by event ID
+        fobj (file): input file
+
+    """
+    while True:
+        t = fobj.read(8)
+        if len(t) == 0:
+            break
+
+        (rectype, ) = struct.unpack('=Q', t)
+        if rectype == record_type_mapping:
+            event_id, name = get_mapping(fobj)
+            idtoname[event_id] = name
+        else:
+            rec = read_record(edict, idtoname, fobj)
+
+            yield rec
+
+class Analyzer(object):
+    """A trace file analyzer which processes trace records.
+
+    An analyzer can be passed to run() or process().  The begin() method is
+    invoked, then each trace record is processed, and finally the end() method
+    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.
+
+    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."""
+        pass
+
+    def catchall(self, event, rec):
+        """Called if no specific method for processing a trace event has been found."""
+        pass
+
+    def end(self):
+        """Called at the end of the trace."""
+        pass
+
+def process(events, log, analyzer, read_header=True):
+    """Invoke an analyzer on each event in a log."""
+    if isinstance(events, str):
+        events = read_events(open(events, 'r'), events)
+    if isinstance(log, str):
+        log = open(log, 'rb')
+
+    if read_header:
+        read_trace_header(log)
+
+    frameinfo = inspect.getframeinfo(inspect.currentframe())
+    dropped_event = Event.build("Dropped_Event(uint64_t num_events_dropped)",
+                                frameinfo.lineno + 1, frameinfo.filename)
+    edict = {"dropped": dropped_event}
+    idtoname = {dropped_event_id: "dropped"}
+
+    for event in events:
+        edict[event.name] = event
+
+    # If there is no header assume event ID mapping matches events list
+    if not read_header:
+        for event_id, event in enumerate(events):
+            idtoname[event_id] = event.name
+
+    def build_fn(analyzer, event):
+        if isinstance(event, str):
+            return analyzer.catchall
+
+        fn = getattr(analyzer, event.name, None)
+        if fn is None:
+            return analyzer.catchall
+
+        event_argcount = len(event.args)
+        fn_argcount = len(inspect.getargspec(fn)[0]) - 1
+        if fn_argcount == event_argcount + 1:
+            # Include timestamp as first argument
+            return lambda _, rec: fn(*(rec[1:2] + rec[3:3 + event_argcount]))
+        elif fn_argcount == event_argcount + 2:
+            # Include timestamp and pid
+            return lambda _, rec: fn(*rec[1:3 + event_argcount])
+        else:
+            # Just arguments, no timestamp or pid
+            return lambda _, rec: fn(*rec[3:3 + event_argcount])
+
+    analyzer.begin()
+    fn_cache = {}
+    for rec in read_trace_records(edict, idtoname, log):
+        event_num = rec[0]
+        event = edict[event_num]
+        if event_num not in fn_cache:
+            fn_cache[event_num] = build_fn(analyzer, event)
+        fn_cache[event_num](event, rec)
+    analyzer.end()
+
+def run(analyzer):
+    """Execute an analyzer on a trace file given on the command-line.
+
+    This function is useful as a driver for simple analysis scripts.  More
+    advanced scripts will want to call process() instead."""
+    import sys
+
+    read_header = True
+    if len(sys.argv) == 4 and sys.argv[1] == '--no-header':
+        read_header = False
+        del sys.argv[1]
+    elif len(sys.argv) != 3:
+        sys.stderr.write('usage: %s [--no-header] <trace-events> ' \
+                         '<trace-file>\n' % sys.argv[0])
+        sys.exit(1)
+
+    events = read_events(open(sys.argv[1], 'r'), sys.argv[1])
+    process(events, sys.argv[2], analyzer, read_header=read_header)
+
+if __name__ == '__main__':
+    class Formatter(Analyzer):
+        def __init__(self):
+            self.last_timestamp = None
+
+        def catchall(self, event, rec):
+            timestamp = rec[1]
+            if self.last_timestamp is None:
+                self.last_timestamp = timestamp
+            delta_ns = timestamp - self.last_timestamp
+            self.last_timestamp = timestamp
+
+            fields = [event.name, '%0.3f' % (delta_ns / 1000.0),
+                      'pid=%d' % rec[2]]
+            i = 3
+            for type, name in event.args:
+                if is_string(type):
+                    fields.append('%s=%s' % (name, rec[i]))
+                else:
+                    fields.append('%s=0x%x' % (name, rec[i]))
+                i += 1
+            print(' '.join(fields))
+
+    run(Formatter())