It looks like python support has been left behind for quite a while. While
the current code builds, there are multiple problems:
- Linker library flags haven't been updated, so the produced ctracecmd.so is
missing dependency on zlib and libzstd which makes the python fail to
load.
- tep_plugin_kvm_get/put_func() cause load failures.
- Some of the tracecmd library functions are made private and swig no longer
generates wrappers for them.
- Some library functions and conventions are changed.
- Recent python3 isn't happy with some older constructs (e.g. DictMixin).
This patch fixes up the python support by:
- Add missing library flags.
- Add %ignore swig directives for tep_plugin_kvm_get/put_func(). They aren't
used by python module anyway.
- Move the prototypes of the following functions from
trace-cmd/include/private/trace-cmd-private.h to
trace-cmd-private-python.h and include it from ctracecmd.i so that the
wrappers are generated for them.
tracecmd_long_size()
tracecmd_cpus()
tracecmd_peek_data()
tracecmd_peek_data_ref()
tracecmd_read_next_data()
- Update the library calls as needed.
- Update to python3
- s/PyEval_CallObject/PyObject_Call/
- Use functools.cached_property instead of the custom one.
- Replace DictMixin with collections.abc.Mapping which requires
implementation of __iter__() and __len__(). Implement them so that all
keys can be iterated and counted.
- Beef up the test code a bit.
This makes it incompatible with python2 but given how long the module has
been broken and how long python3 has been widespread, concentrating on
python3 support seems reasonable.
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
Hello,
The trace-cmd-private-python.h part is kinda ugly. Please let me know if
anyone has better ideas.
Thanks.
Makefile | 2 +-
.../private/trace-cmd-private-python.h | 27 +++++++
.../include/private/trace-cmd-private.h | 18 +----
python/Makefile | 7 +-
python/ctracecmd.i | 10 ++-
python/tracecmd.py | 71 +++++++++----------
6 files changed, 76 insertions(+), 59 deletions(-)
create mode 100644 lib/trace-cmd/include/private/trace-cmd-private-python.h
diff --git a/Makefile b/Makefile
index ea83f60..c2c819e 100644
--- a/Makefile
+++ b/Makefile
@@ -144,7 +144,7 @@ endif
ifndef NO_PYTHON
PYTHON := ctracecmd.so
-PYTHON_VERS ?= python
+PYTHON_VERS ?= python3
PYTHON_PKGCONFIG_VERS ?= $(PYTHON_VERS)
# Can build python?
diff --git a/lib/trace-cmd/include/private/trace-cmd-private-python.h b/lib/trace-cmd/include/private/trace-cmd-private-python.h
new file mode 100644
index 0000000..ddc52f1
--- /dev/null
+++ b/lib/trace-cmd/include/private/trace-cmd-private-python.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
+/*
+ * Private interface exposed to the python module. See python/ctracecmd.i and
+ * python/tracecmd.py.
+ */
+#ifndef _TRACE_CMD_PRIVATE_PYTHON_H
+#define _TRACE_CMD_PRIVATE_PYTHON_H
+
+int tracecmd_long_size(struct tracecmd_input *handle);
+int tracecmd_cpus(struct tracecmd_input *handle);
+
+struct tep_record *
+tracecmd_read_next_data(struct tracecmd_input *handle, int *rec_cpu);
+
+struct tep_record *
+tracecmd_peek_data(struct tracecmd_input *handle, int cpu);
+
+static inline struct tep_record *
+tracecmd_peek_data_ref(struct tracecmd_input *handle, int cpu)
+{
+ struct tep_record *rec = tracecmd_peek_data(handle, cpu);
+ if (rec)
+ rec->ref_count++;
+ return rec;
+}
+
+#endif /* _TRACE_CMD_PRIVATE_PYTHON_H */
diff --git a/lib/trace-cmd/include/private/trace-cmd-private.h b/lib/trace-cmd/include/private/trace-cmd-private.h
index f2cf8dc..6173001 100644
--- a/lib/trace-cmd/include/private/trace-cmd-private.h
+++ b/lib/trace-cmd/include/private/trace-cmd-private.h
@@ -10,6 +10,7 @@
#include <sys/types.h>
#include "event-parse.h"
#include "trace-cmd/trace-cmd.h"
+#include "trace-cmd-private-python.h"
#define __packed __attribute__((packed))
#define __hidden __attribute__((visibility ("hidden")))
@@ -194,9 +195,7 @@ void tracecmd_ref(struct tracecmd_input *handle);
int tracecmd_read_headers(struct tracecmd_input *handle,
enum tracecmd_file_states state);
int tracecmd_get_parsing_failures(struct tracecmd_input *handle);
-int tracecmd_long_size(struct tracecmd_input *handle);
int tracecmd_page_size(struct tracecmd_input *handle);
-int tracecmd_cpus(struct tracecmd_input *handle);
int tracecmd_copy_headers(struct tracecmd_input *in_handle,
struct tracecmd_output *out_handle,
enum tracecmd_file_states start_state,
@@ -230,26 +229,11 @@ void tracecmd_print_stats(struct tracecmd_input *handle);
void tracecmd_print_uname(struct tracecmd_input *handle);
void tracecmd_print_version(struct tracecmd_input *handle);
-struct tep_record *
-tracecmd_peek_data(struct tracecmd_input *handle, int cpu);
-
-static inline struct tep_record *
-tracecmd_peek_data_ref(struct tracecmd_input *handle, int cpu)
-{
- struct tep_record *rec = tracecmd_peek_data(handle, cpu);
- if (rec)
- rec->ref_count++;
- return rec;
-}
-
int tracecmd_latency_data_read(struct tracecmd_input *handle, char **buf, size_t *size);
struct tep_record *
tracecmd_read_prev(struct tracecmd_input *handle, struct tep_record *record);
-struct tep_record *
-tracecmd_read_next_data(struct tracecmd_input *handle, int *rec_cpu);
-
struct tep_record *
tracecmd_peek_next_data(struct tracecmd_input *handle, int *rec_cpu);
diff --git a/python/Makefile b/python/Makefile
index 63f5736..926e64c 100644
--- a/python/Makefile
+++ b/python/Makefile
@@ -9,9 +9,12 @@ PYTHON_PY_LIBS := tracecmd.install
endif
ctracecmd.so: ctracecmd.i $(LIBTRACECMD_STATIC)
- swig -Wall -python -noproxy -I$(src)/include/trace-cmd $(LIBTRACEEVENT_CFLAGS) ctracecmd.i
+ swig -Wall -python -noproxy \
+ -I$(src)/include/trace-cmd -I$(src)/lib/trace-cmd/include/private \
+ $(LIBTRACEEVENT_CFLAGS) ctracecmd.i
$(CC) -fpic -c $(CPPFLAGS) $(CFLAGS) $(PYTHON_INCLUDES) ctracecmd_wrap.c
- $(CC) --shared $(LIBTRACECMD_STATIC) $(LDFLAGS) ctracecmd_wrap.o -o ctracecmd.so $(TRACE_LIBS)
+ $(CC) --shared $(LIBTRACECMD_STATIC) $(LDFLAGS) $(LIBZSTD_LDLAGS) $(ZLIB_LDLAGS) \
+ ctracecmd_wrap.o -o ctracecmd.so $(TRACE_LIBS)
$(PYTHON_SO_INSTALL): %.install : %.so force
$(Q)$(call do_install_data,$<,$(python_dir_SQ))
diff --git a/python/ctracecmd.i b/python/ctracecmd.i
index 6d0179e..3856460 100644
--- a/python/ctracecmd.i
+++ b/python/ctracecmd.i
@@ -15,6 +15,7 @@
%{
#include "trace-cmd.h"
+#include "trace-cmd-private-python.h"
#include "event-parse.h"
#include "event-utils.h"
#include <Python.h>
@@ -176,14 +177,14 @@ static PyObject *py_field_get_str(struct tep_format_field *f, struct tep_record
strnlen((char *)r->data + f->offset, f->size));
}
-static PyObject *py_format_get_keys(struct tep_event *ef)
+static PyObject *py_format_get_keys(struct tep_event *ef, bool common_keys)
{
PyObject *list;
struct tep_format_field *f;
list = PyList_New(0);
- for (f = ef->format.fields; f; f = f->next) {
+ for (f = common_keys ? ef->format.common_fields : ef->format.fields; f; f = f->next) {
if (PyList_Append(list, PyUnicode_FromString(f->name))) {
Py_DECREF(list);
return NULL;
@@ -214,7 +215,7 @@ static int python_callback(struct trace_seq *s,
SWIG_NewPointerObj(SWIG_as_voidptr(event),
SWIGTYPE_p_tep_event, 0));
- result = PyEval_CallObject(context, arglist);
+ result = PyObject_Call(context, arglist, NULL);
Py_XDECREF(arglist);
if (result && result != Py_None) {
if (!PyInt_Check(result)) {
@@ -239,6 +240,8 @@ static int python_callback(struct trace_seq *s,
%ignore trace_seq_vprintf;
%ignore vpr_stat;
+%ignore tep_plugin_kvm_get_func;
+%ignore tep_plugin_kvm_put_func;
/* SWIG can't grok these, define them to nothing */
#define __trace
@@ -246,5 +249,6 @@ static int python_callback(struct trace_seq *s,
#define __thread
%include "trace-cmd.h"
+%include "trace-cmd-private-python.h"
%include <trace-seq.h>
%include <event-parse.h>
diff --git a/python/tracecmd.py b/python/tracecmd.py
index 4d48157..6761f8a 100644
--- a/python/tracecmd.py
+++ b/python/tracecmd.py
@@ -18,9 +18,10 @@
# 2009-Dec-17: Initial version by Darren Hart <dvhltc@xxxxxxxxxx>
#
-from functools import update_wrapper
+from functools import cached_property
+from collections.abc import Mapping
+from itertools import chain
from ctracecmd import *
-from UserDict import DictMixin
"""
Python interface to the tracecmd library for parsing ftrace traces
@@ -33,25 +34,7 @@ and it is recommended applications not use it directly.
TODO: consider a complete class hierarchy of ftrace events...
"""
-def cached_property(func, name=None):
- if name is None:
- name = func.__name__
- def _get(self):
- try:
- return self.__cached_properties[name]
- except AttributeError:
- self.__cached_properties = {}
- except KeyError:
- pass
- value = func(self)
- self.__cached_properties[name] = value
- return value
- update_wrapper(_get, func)
- def _del(self):
- self.__cached_properties.pop(name, None)
- return property(_get, None, _del)
-
-class Event(object, DictMixin):
+class Event(Mapping):
"""
This class can be used to access event data
according to an event's record and format.
@@ -67,16 +50,30 @@ TODO: consider a complete class hierarchy of ftrace events...
self.num_field("common_pid"), self.comm, self.type)
def __del__(self):
- free_record(self._record)
+ tracecmd_free_record(self._record)
def __getitem__(self, n):
- f = tep_find_field(self._format, n)
+ if n.startswith('common_'):
+ f = tep_find_common_field(self._format, n)
+ else:
+ f = tep_find_field(self._format, n)
if f is None:
raise KeyError("no field '%s'" % n)
return Field(self._record, f)
+ def __iter__(self):
+ yield from chain(self.common_keys, self.keys)
+
+ def __len__(self):
+ return len(self.common_keys) + len(self.keys)
+
+ @cached_property
+ def common_keys(self):
+ return py_format_get_keys(self._format, True)
+
+ @cached_property
def keys(self):
- return py_format_get_keys(self._format)
+ return py_format_get_keys(self._format, False)
@cached_property
def comm(self):
@@ -88,7 +85,7 @@ TODO: consider a complete class hierarchy of ftrace events...
@cached_property
def name(self):
- return event_format_name_get(self._format)
+ return tep_event_name_get(self._format)
@cached_property
def pid(self):
@@ -182,15 +179,8 @@ TODO: consider a complete class hierarchy of ftrace events...
used to manage the trace and extract events from it.
"""
def __init__(self, filename):
- self._handle = tracecmd_alloc(filename)
-
- if tracecmd_read_headers(self._handle):
- raise FileFormatError("Invalid headers")
-
- if tracecmd_init_data(self._handle):
- raise FileFormatError("Failed to init data")
-
- self._pevent = tracecmd_get_pevent(self._handle)
+ self._handle = tracecmd_open(filename, 0)
+ self._pevent = tracecmd_get_tep(self._handle)
@cached_property
def cpus(self):
@@ -242,8 +232,12 @@ TODO: consider a complete class hierarchy of ftrace events...
# Basic builtin test, execute module directly
if __name__ == "__main__":
t = Trace("trace.dat")
- print("Trace contains data for %d cpus" % (t.cpus))
+ print(f"Trace contains data for {t.cpus} cpus, long has {t.long_size} bytes")
+
+ print("Peek the first event on CPU0")
+ print("\t%s" % (t.peek_event(0)))
+ print("Events by CPUs")
for cpu in range(0, t.cpus):
print("CPU %d" % (cpu))
ev = t.read_event(cpu)
@@ -251,5 +245,10 @@ TODO: consider a complete class hierarchy of ftrace events...
print("\t%s" % (ev))
ev = t.read_event(cpu)
+ t = Trace("trace.dat")
-
+ print("Events by time")
+ ev = t.read_next_event()
+ while ev:
+ print("\t%s" % (ev))
+ ev = t.read_next_event()
--
2.39.1
|