[PATCH] perf/scripts: tuple was set from long in both branches in python_process_event()

[Roel Kluin]

Regardless of the sign, the tuple was set from a long.

Signed-off-by: Roel Kluin <roel....@gmail.com>
---
.../util/scripting-engines/trace-event-python.c | 13 ++++++++-----
1 files changed, 8 insertions(+), 5 deletions(-)

Was something like this intended?

diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index 33a414b..1d710b6 100644
--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c
@@ -208,7 +208,7 @@ static void python_process_event(int cpu, void *data,
int size __unused,
unsigned long long nsecs, char *comm)
{
- PyObject *handler, *retval, *context, *t;
+ PyObject *handler, *retval, *context, *t, *obj;
static char handler_name[256];
struct format_field *field;
unsigned long long val;
@@ -256,16 +256,19 @@ static void python_process_event(int cpu, void *data,
offset &= 0xffff;
} else
offset = field->offset;
- PyTuple_SetItem(t, n++,
- PyString_FromString((char *)data + offset));
+ obj = PyString_FromString((char *)data + offset);
} else { /* FIELD_IS_NUMERIC */
val = read_size(data + field->offset, field->size);
if (field->flags & FIELD_IS_SIGNED) {
- PyTuple_SetItem(t, n++, PyInt_FromLong(val));
+ obj = PyInt_FromLong(val);
} else {
- PyTuple_SetItem(t, n++, PyInt_FromLong(val));
+ if (sizeof(val) > sizeof(Py_ssize_t))
+ val += 1ULL <<
+ (sizeof(Py_ssize_t) * 8);
+ obj = PyLong_FromUnsignedLongLong(val);
}
}
+ PyTuple_SetItem(t, n++, obj);
}

if (_PyTuple_Resize(&t, n) == -1)

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[Tom Zanussi]

Hi,

On Mon, 2010-03-22 at 18:22 +0100, Roel Kluin wrote:
> Regardless of the sign, the tuple was set from a long.
>
> Signed-off-by: Roel Kluin <roel....@gmail.com>
> ---
> .../util/scripting-engines/trace-event-python.c | 13 ++++++++-----
> 1 files changed, 8 insertions(+), 5 deletions(-)
>
> Was something like this intended?

Yeah, something like that - thanks for noticing it and providing the
patch. After looking at the Python implementation, I modified your
patch as below...

Basically, Python wants to use a PyInt (which is internally a long) if
it can i.e. if the value will fit into that type. If not, it stores it
into a PyLong, which isn't actually a long, but an arbitrary-precision
integer variable.

The code below is similar to to what Python does internally, and it
seems to work as expected on the x86 and x86_64 sytems I tested it on.

Thanks,

Tom

Signed-off-by: Tom Zanussi <tzan...@gmail.com>

diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index 33a414b..6a72f14 100644

--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c
@@ -208,7 +208,7 @@ static void python_process_event(int cpu, void *data,
int size __unused,
unsigned long long nsecs, char *comm)
{
- PyObject *handler, *retval, *context, *t;
+ PyObject *handler, *retval, *context, *t, *obj;
static char handler_name[256];
struct format_field *field;
unsigned long long val;

@@ -256,16 +256,23 @@ static void python_process_event(int cpu, void *data,

offset &= 0xffff;
} else
offset = field->offset;
- PyTuple_SetItem(t, n++,
- PyString_FromString((char *)data + offset));
+ obj = PyString_FromString((char *)data + offset);
} else { /* FIELD_IS_NUMERIC */
val = read_size(data + field->offset, field->size);
if (field->flags & FIELD_IS_SIGNED) {
- PyTuple_SetItem(t, n++, PyInt_FromLong(val));

+ if ((long long)val >= LONG_MIN &&
+ (long long)val <= LONG_MAX)
+ obj = PyInt_FromLong(val);
+ else
+ obj = PyLong_FromLongLong(val);

} else {
- PyTuple_SetItem(t, n++, PyInt_FromLong(val));

+ if (val <= LONG_MAX)
+ obj = PyInt_FromLong(val);
+ else

[Tom Zanussi]

This is a fix to the signed/unsigned field handling in the Python
scripting engine, based on a patch from Roel Kluin.

Basically, Python wants to use a PyInt (which is internally a long) if
it can i.e. if the value will fit into that type. If not, it stores it
into a PyLong, which isn't actually a long, but an arbitrary-precision
integer variable.

The code below is similar to to what Python does internally, and it
seems to work as expected on the x86 and x86_64 sytems I tested it on.

Signed-off-by: Tom Zanussi <tzan...@gmail.com>
---
.../util/scripting-engines/trace-event-python.c | 17 ++++++++++++-----
1 files changed, 12 insertions(+), 5 deletions(-)

1.6.4.GIT

[tip-bot for Tom Zanussi]

Commit-ID: b1dcc03cb8ee0f5718491e8c518257238dc64e00
Gitweb: http://git.kernel.org/tip/b1dcc03cb8ee0f5718491e8c518257238dc64e00
Author: Tom Zanussi <tzan...@gmail.com>
AuthorDate: Thu, 1 Apr 2010 23:58:25 -0500
Committer: Ingo Molnar <mi...@elte.hu>
CommitDate: Fri, 2 Apr 2010 21:32:16 +0200

perf/scripts: Tuple was set from long in both branches in python_process_event()

This is a fix to the signed/unsigned field handling in the
Python scripting engine, based on a patch from Roel Kluin.

Basically, Python wants to use a PyInt (which is internally a
long) if it can i.e. if the value will fit into that type. If
not, it stores it into a PyLong, which isn't actually a long,
but an arbitrary-precision integer variable.

The code below is similar to to what Python does internally, and
it seems to work as expected on the x86 and x86_64 sytems I
tested it on.

Signed-off-by: Tom Zanussi <tzan...@gmail.com>
Cc: Arnaldo Carvalho de Melo <ac...@redhat.com>
Cc: Roel Kluin <roel....@gmail.com>
Cc: Frederic Weisbecker <fwei...@gmail.com>
Cc: ros...@goodmis.org
LKML-Reference: <1270184305.6422.10.camel@tropicana>
Signed-off-by: Ingo Molnar <mi...@elte.hu>