Merge tag 'driver-core-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...

[deliverable/linux.git] / tools / perf / util / scripting-engines / trace-event-python.c

/*
 * trace-event-python.  Feed trace events to an embedded Python interpreter.
 *
 * Copyright (C) 2010 Tom Zanussi <tzanussi@gmail.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <Python.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <errno.h>
#include <linux/bitmap.h>

#include "../../perf.h"
#include "../debug.h"
#include "../callchain.h"
#include "../evsel.h"
#include "../util.h"
#include "../event.h"
#include "../thread.h"
#include "../comm.h"
#include "../machine.h"
#include "../db-export.h"
#include "../thread-stack.h"
#include "../trace-event.h"
#include "../machine.h"
#include "../call-path.h"
#include "thread_map.h"
#include "cpumap.h"
#include "stat.h"

PyMODINIT_FUNC initperf_trace_context(void);

#define TRACE_EVENT_TYPE_MAX                            \
        ((1 << (sizeof(unsigned short) * 8)) - 1)

static DECLARE_BITMAP(events_defined, TRACE_EVENT_TYPE_MAX);

#define MAX_FIELDS      64
#define N_COMMON_FIELDS 7

extern struct scripting_context *scripting_context;

static char *cur_field_name;
static int zero_flag_atom;

static PyObject *main_module, *main_dict;

struct tables {
        struct db_export        dbe;
        PyObject                *evsel_handler;
        PyObject                *machine_handler;
        PyObject                *thread_handler;
        PyObject                *comm_handler;
        PyObject                *comm_thread_handler;
        PyObject                *dso_handler;
        PyObject                *symbol_handler;
        PyObject                *branch_type_handler;
        PyObject                *sample_handler;
        PyObject                *call_path_handler;
        PyObject                *call_return_handler;
        bool                    db_export_mode;
};

static struct tables tables_global;

static void handler_call_die(const char *handler_name) NORETURN;
static void handler_call_die(const char *handler_name)
{
        PyErr_Print();
        Py_FatalError("problem in Python trace event handler");
        // Py_FatalError does not return
        // but we have to make the compiler happy
        abort();
}

/*
 * Insert val into into the dictionary and decrement the reference counter.
 * This is necessary for dictionaries since PyDict_SetItemString() does not
 * steal a reference, as opposed to PyTuple_SetItem().
 */
static void pydict_set_item_string_decref(PyObject *dict, const char *key, PyObject *val)
{
        PyDict_SetItemString(dict, key, val);
        Py_DECREF(val);
}

static PyObject *get_handler(const char *handler_name)
{
        PyObject *handler;

        handler = PyDict_GetItemString(main_dict, handler_name);
        if (handler && !PyCallable_Check(handler))
                return NULL;
        return handler;
}

static void call_object(PyObject *handler, PyObject *args, const char *die_msg)
{
        PyObject *retval;

        retval = PyObject_CallObject(handler, args);
        if (retval == NULL)
                handler_call_die(die_msg);
        Py_DECREF(retval);
}

static void try_call_object(const char *handler_name, PyObject *args)
{
        PyObject *handler;

        handler = get_handler(handler_name);
        if (handler)
                call_object(handler, args, handler_name);
}

static void define_value(enum print_arg_type field_type,
                         const char *ev_name,
                         const char *field_name,
                         const char *field_value,
                         const char *field_str)
{
        const char *handler_name = "define_flag_value";
        PyObject *t;
        unsigned long long value;
        unsigned n = 0;

        if (field_type == PRINT_SYMBOL)
                handler_name = "define_symbolic_value";

        t = PyTuple_New(4);
        if (!t)
                Py_FatalError("couldn't create Python tuple");

        value = eval_flag(field_value);

        PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
        PyTuple_SetItem(t, n++, PyString_FromString(field_name));
        PyTuple_SetItem(t, n++, PyInt_FromLong(value));
        PyTuple_SetItem(t, n++, PyString_FromString(field_str));

        try_call_object(handler_name, t);

        Py_DECREF(t);
}

static void define_values(enum print_arg_type field_type,
                          struct print_flag_sym *field,
                          const char *ev_name,
                          const char *field_name)
{
        define_value(field_type, ev_name, field_name, field->value,
                     field->str);

        if (field->next)
                define_values(field_type, field->next, ev_name, field_name);
}

static void define_field(enum print_arg_type field_type,
                         const char *ev_name,
                         const char *field_name,
                         const char *delim)
{
        const char *handler_name = "define_flag_field";
        PyObject *t;
        unsigned n = 0;

        if (field_type == PRINT_SYMBOL)
                handler_name = "define_symbolic_field";

        if (field_type == PRINT_FLAGS)
                t = PyTuple_New(3);
        else
                t = PyTuple_New(2);
        if (!t)
                Py_FatalError("couldn't create Python tuple");

        PyTuple_SetItem(t, n++, PyString_FromString(ev_name));
        PyTuple_SetItem(t, n++, PyString_FromString(field_name));
        if (field_type == PRINT_FLAGS)
                PyTuple_SetItem(t, n++, PyString_FromString(delim));

        try_call_object(handler_name, t);

        Py_DECREF(t);
}

static void define_event_symbols(struct event_format *event,
                                 const char *ev_name,
                                 struct print_arg *args)
{
        if (args == NULL)
                return;

        switch (args->type) {
        case PRINT_NULL:
                break;
        case PRINT_ATOM:
                define_value(PRINT_FLAGS, ev_name, cur_field_name, "0",
                             args->atom.atom);
                zero_flag_atom = 0;
                break;
        case PRINT_FIELD:
                free(cur_field_name);
                cur_field_name = strdup(args->field.name);
                break;
        case PRINT_FLAGS:
                define_event_symbols(event, ev_name, args->flags.field);
                define_field(PRINT_FLAGS, ev_name, cur_field_name,
                             args->flags.delim);
                define_values(PRINT_FLAGS, args->flags.flags, ev_name,
                              cur_field_name);
                break;
        case PRINT_SYMBOL:
                define_event_symbols(event, ev_name, args->symbol.field);
                define_field(PRINT_SYMBOL, ev_name, cur_field_name, NULL);
                define_values(PRINT_SYMBOL, args->symbol.symbols, ev_name,
                              cur_field_name);
                break;
        case PRINT_HEX:
                define_event_symbols(event, ev_name, args->hex.field);
                define_event_symbols(event, ev_name, args->hex.size);
                break;
        case PRINT_INT_ARRAY:
                define_event_symbols(event, ev_name, args->int_array.field);
                define_event_symbols(event, ev_name, args->int_array.count);
                define_event_symbols(event, ev_name, args->int_array.el_size);
                break;
        case PRINT_STRING:
                break;
        case PRINT_TYPE:
                define_event_symbols(event, ev_name, args->typecast.item);
                break;
        case PRINT_OP:
                if (strcmp(args->op.op, ":") == 0)
                        zero_flag_atom = 1;
                define_event_symbols(event, ev_name, args->op.left);
                define_event_symbols(event, ev_name, args->op.right);
                break;
        default:
                /* gcc warns for these? */
        case PRINT_BSTRING:
        case PRINT_DYNAMIC_ARRAY:
        case PRINT_DYNAMIC_ARRAY_LEN:
        case PRINT_FUNC:
        case PRINT_BITMASK:
                /* we should warn... */
                return;
        }

        if (args->next)
                define_event_symbols(event, ev_name, args->next);
}

static PyObject *get_field_numeric_entry(struct event_format *event,
                struct format_field *field, void *data)
{
        bool is_array = field->flags & FIELD_IS_ARRAY;
        PyObject *obj, *list = NULL;
        unsigned long long val;
        unsigned int item_size, n_items, i;

        if (is_array) {
                list = PyList_New(field->arraylen);
                item_size = field->size / field->arraylen;
                n_items = field->arraylen;
        } else {
                item_size = field->size;
                n_items = 1;
        }

        for (i = 0; i < n_items; i++) {

                val = read_size(event, data + field->offset + i * item_size,
                                item_size);
                if (field->flags & FIELD_IS_SIGNED) {
                        if ((long long)val >= LONG_MIN &&
                                        (long long)val <= LONG_MAX)
                                obj = PyInt_FromLong(val);
                        else
                                obj = PyLong_FromLongLong(val);
                } else {
                        if (val <= LONG_MAX)
                                obj = PyInt_FromLong(val);
                        else
                                obj = PyLong_FromUnsignedLongLong(val);
                }
                if (is_array)
                        PyList_SET_ITEM(list, i, obj);
        }
        if (is_array)
                obj = list;
        return obj;
}


static PyObject *python_process_callchain(struct perf_sample *sample,
                                         struct perf_evsel *evsel,
                                         struct addr_location *al)
{
        PyObject *pylist;

        pylist = PyList_New(0);
        if (!pylist)
                Py_FatalError("couldn't create Python list");

        if (!symbol_conf.use_callchain || !sample->callchain)
                goto exit;

        if (thread__resolve_callchain(al->thread, &callchain_cursor, evsel,
                                      sample, NULL, NULL,
                                      scripting_max_stack) != 0) {
                pr_err("Failed to resolve callchain. Skipping\n");
                goto exit;
        }
        callchain_cursor_commit(&callchain_cursor);


        while (1) {
                PyObject *pyelem;
                struct callchain_cursor_node *node;
                node = callchain_cursor_current(&callchain_cursor);
                if (!node)
                        break;

                pyelem = PyDict_New();
                if (!pyelem)
                        Py_FatalError("couldn't create Python dictionary");


                pydict_set_item_string_decref(pyelem, "ip",
                                PyLong_FromUnsignedLongLong(node->ip));

                if (node->sym) {
                        PyObject *pysym  = PyDict_New();
                        if (!pysym)
                                Py_FatalError("couldn't create Python dictionary");
                        pydict_set_item_string_decref(pysym, "start",
                                        PyLong_FromUnsignedLongLong(node->sym->start));
                        pydict_set_item_string_decref(pysym, "end",
                                        PyLong_FromUnsignedLongLong(node->sym->end));
                        pydict_set_item_string_decref(pysym, "binding",
                                        PyInt_FromLong(node->sym->binding));
                        pydict_set_item_string_decref(pysym, "name",
                                        PyString_FromStringAndSize(node->sym->name,
                                                        node->sym->namelen));
                        pydict_set_item_string_decref(pyelem, "sym", pysym);
                }

                if (node->map) {
                        struct map *map = node->map;
                        const char *dsoname = "[unknown]";
                        if (map && map->dso && (map->dso->name || map->dso->long_name)) {
                                if (symbol_conf.show_kernel_path && map->dso->long_name)
                                        dsoname = map->dso->long_name;
                                else if (map->dso->name)
                                        dsoname = map->dso->name;
                        }
                        pydict_set_item_string_decref(pyelem, "dso",
                                        PyString_FromString(dsoname));
                }

                callchain_cursor_advance(&callchain_cursor);
                PyList_Append(pylist, pyelem);
                Py_DECREF(pyelem);
        }

exit:
        return pylist;
}


static void python_process_tracepoint(struct perf_sample *sample,
                                      struct perf_evsel *evsel,
                                      struct addr_location *al)
{
        struct event_format *event = evsel->tp_format;
        PyObject *handler, *context, *t, *obj, *callchain;
        PyObject *dict = NULL;
        static char handler_name[256];
        struct format_field *field;
        unsigned long s, ns;
        unsigned n = 0;
        int pid;
        int cpu = sample->cpu;
        void *data = sample->raw_data;
        unsigned long long nsecs = sample->time;
        const char *comm = thread__comm_str(al->thread);

        t = PyTuple_New(MAX_FIELDS);
        if (!t)
                Py_FatalError("couldn't create Python tuple");

        if (!event) {
                snprintf(handler_name, sizeof(handler_name),
                         "ug! no event found for type %" PRIu64, (u64)evsel->attr.config);
                Py_FatalError(handler_name);
        }

        pid = raw_field_value(event, "common_pid", data);

        sprintf(handler_name, "%s__%s", event->system, event->name);

        if (!test_and_set_bit(event->id, events_defined))
                define_event_symbols(event, handler_name, event->print_fmt.args);

        handler = get_handler(handler_name);
        if (!handler) {
                dict = PyDict_New();
                if (!dict)
                        Py_FatalError("couldn't create Python dict");
        }
        s = nsecs / NSECS_PER_SEC;
        ns = nsecs - s * NSECS_PER_SEC;

        scripting_context->event_data = data;
        scripting_context->pevent = evsel->tp_format->pevent;

        context = PyCObject_FromVoidPtr(scripting_context, NULL);

        PyTuple_SetItem(t, n++, PyString_FromString(handler_name));
        PyTuple_SetItem(t, n++, context);

        /* ip unwinding */
        callchain = python_process_callchain(sample, evsel, al);

        if (handler) {
                PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
                PyTuple_SetItem(t, n++, PyInt_FromLong(s));
                PyTuple_SetItem(t, n++, PyInt_FromLong(ns));
                PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
                PyTuple_SetItem(t, n++, PyString_FromString(comm));
                PyTuple_SetItem(t, n++, callchain);
        } else {
                pydict_set_item_string_decref(dict, "common_cpu", PyInt_FromLong(cpu));
                pydict_set_item_string_decref(dict, "common_s", PyInt_FromLong(s));
                pydict_set_item_string_decref(dict, "common_ns", PyInt_FromLong(ns));
                pydict_set_item_string_decref(dict, "common_pid", PyInt_FromLong(pid));
                pydict_set_item_string_decref(dict, "common_comm", PyString_FromString(comm));
                pydict_set_item_string_decref(dict, "common_callchain", callchain);
        }
        for (field = event->format.fields; field; field = field->next) {
                if (field->flags & FIELD_IS_STRING) {
                        int offset;
                        if (field->flags & FIELD_IS_DYNAMIC) {
                                offset = *(int *)(data + field->offset);
                                offset &= 0xffff;
                        } else
                                offset = field->offset;
                        obj = PyString_FromString((char *)data + offset);
                } else { /* FIELD_IS_NUMERIC */
                        obj = get_field_numeric_entry(event, field, data);
                }
                if (handler)
                        PyTuple_SetItem(t, n++, obj);
                else
                        pydict_set_item_string_decref(dict, field->name, obj);

        }

        if (!handler)
                PyTuple_SetItem(t, n++, dict);

        if (_PyTuple_Resize(&t, n) == -1)
                Py_FatalError("error resizing Python tuple");

        if (handler) {
                call_object(handler, t, handler_name);
        } else {
                try_call_object("trace_unhandled", t);
                Py_DECREF(dict);
        }

        Py_DECREF(t);
}

static PyObject *tuple_new(unsigned int sz)
{
        PyObject *t;

        t = PyTuple_New(sz);
        if (!t)
                Py_FatalError("couldn't create Python tuple");
        return t;
}

static int tuple_set_u64(PyObject *t, unsigned int pos, u64 val)
{
#if BITS_PER_LONG == 64
        return PyTuple_SetItem(t, pos, PyInt_FromLong(val));
#endif
#if BITS_PER_LONG == 32
        return PyTuple_SetItem(t, pos, PyLong_FromLongLong(val));
#endif
}

static int tuple_set_s32(PyObject *t, unsigned int pos, s32 val)
{
        return PyTuple_SetItem(t, pos, PyInt_FromLong(val));
}

static int tuple_set_string(PyObject *t, unsigned int pos, const char *s)
{
        return PyTuple_SetItem(t, pos, PyString_FromString(s));
}

static int python_export_evsel(struct db_export *dbe, struct perf_evsel *evsel)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(2);

        tuple_set_u64(t, 0, evsel->db_id);
        tuple_set_string(t, 1, perf_evsel__name(evsel));

        call_object(tables->evsel_handler, t, "evsel_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_machine(struct db_export *dbe,
                                 struct machine *machine)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(3);

        tuple_set_u64(t, 0, machine->db_id);
        tuple_set_s32(t, 1, machine->pid);
        tuple_set_string(t, 2, machine->root_dir ? machine->root_dir : "");

        call_object(tables->machine_handler, t, "machine_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_thread(struct db_export *dbe, struct thread *thread,
                                u64 main_thread_db_id, struct machine *machine)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(5);

        tuple_set_u64(t, 0, thread->db_id);
        tuple_set_u64(t, 1, machine->db_id);
        tuple_set_u64(t, 2, main_thread_db_id);
        tuple_set_s32(t, 3, thread->pid_);
        tuple_set_s32(t, 4, thread->tid);

        call_object(tables->thread_handler, t, "thread_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_comm(struct db_export *dbe, struct comm *comm)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(2);

        tuple_set_u64(t, 0, comm->db_id);
        tuple_set_string(t, 1, comm__str(comm));

        call_object(tables->comm_handler, t, "comm_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_comm_thread(struct db_export *dbe, u64 db_id,
                                     struct comm *comm, struct thread *thread)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(3);

        tuple_set_u64(t, 0, db_id);
        tuple_set_u64(t, 1, comm->db_id);
        tuple_set_u64(t, 2, thread->db_id);

        call_object(tables->comm_thread_handler, t, "comm_thread_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_dso(struct db_export *dbe, struct dso *dso,
                             struct machine *machine)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        char sbuild_id[SBUILD_ID_SIZE];
        PyObject *t;

        build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);

        t = tuple_new(5);

        tuple_set_u64(t, 0, dso->db_id);
        tuple_set_u64(t, 1, machine->db_id);
        tuple_set_string(t, 2, dso->short_name);
        tuple_set_string(t, 3, dso->long_name);
        tuple_set_string(t, 4, sbuild_id);

        call_object(tables->dso_handler, t, "dso_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_symbol(struct db_export *dbe, struct symbol *sym,
                                struct dso *dso)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        u64 *sym_db_id = symbol__priv(sym);
        PyObject *t;

        t = tuple_new(6);

        tuple_set_u64(t, 0, *sym_db_id);
        tuple_set_u64(t, 1, dso->db_id);
        tuple_set_u64(t, 2, sym->start);
        tuple_set_u64(t, 3, sym->end);
        tuple_set_s32(t, 4, sym->binding);
        tuple_set_string(t, 5, sym->name);

        call_object(tables->symbol_handler, t, "symbol_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_branch_type(struct db_export *dbe, u32 branch_type,
                                     const char *name)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(2);

        tuple_set_s32(t, 0, branch_type);
        tuple_set_string(t, 1, name);

        call_object(tables->branch_type_handler, t, "branch_type_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_sample(struct db_export *dbe,
                                struct export_sample *es)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;

        t = tuple_new(22);

        tuple_set_u64(t, 0, es->db_id);
        tuple_set_u64(t, 1, es->evsel->db_id);
        tuple_set_u64(t, 2, es->al->machine->db_id);
        tuple_set_u64(t, 3, es->al->thread->db_id);
        tuple_set_u64(t, 4, es->comm_db_id);
        tuple_set_u64(t, 5, es->dso_db_id);
        tuple_set_u64(t, 6, es->sym_db_id);
        tuple_set_u64(t, 7, es->offset);
        tuple_set_u64(t, 8, es->sample->ip);
        tuple_set_u64(t, 9, es->sample->time);
        tuple_set_s32(t, 10, es->sample->cpu);
        tuple_set_u64(t, 11, es->addr_dso_db_id);
        tuple_set_u64(t, 12, es->addr_sym_db_id);
        tuple_set_u64(t, 13, es->addr_offset);
        tuple_set_u64(t, 14, es->sample->addr);
        tuple_set_u64(t, 15, es->sample->period);
        tuple_set_u64(t, 16, es->sample->weight);
        tuple_set_u64(t, 17, es->sample->transaction);
        tuple_set_u64(t, 18, es->sample->data_src);
        tuple_set_s32(t, 19, es->sample->flags & PERF_BRANCH_MASK);
        tuple_set_s32(t, 20, !!(es->sample->flags & PERF_IP_FLAG_IN_TX));
        tuple_set_u64(t, 21, es->call_path_id);

        call_object(tables->sample_handler, t, "sample_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_call_path(struct db_export *dbe, struct call_path *cp)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        PyObject *t;
        u64 parent_db_id, sym_db_id;

        parent_db_id = cp->parent ? cp->parent->db_id : 0;
        sym_db_id = cp->sym ? *(u64 *)symbol__priv(cp->sym) : 0;

        t = tuple_new(4);

        tuple_set_u64(t, 0, cp->db_id);
        tuple_set_u64(t, 1, parent_db_id);
        tuple_set_u64(t, 2, sym_db_id);
        tuple_set_u64(t, 3, cp->ip);

        call_object(tables->call_path_handler, t, "call_path_table");

        Py_DECREF(t);

        return 0;
}

static int python_export_call_return(struct db_export *dbe,
                                     struct call_return *cr)
{
        struct tables *tables = container_of(dbe, struct tables, dbe);
        u64 comm_db_id = cr->comm ? cr->comm->db_id : 0;
        PyObject *t;

        t = tuple_new(11);

        tuple_set_u64(t, 0, cr->db_id);
        tuple_set_u64(t, 1, cr->thread->db_id);
        tuple_set_u64(t, 2, comm_db_id);
        tuple_set_u64(t, 3, cr->cp->db_id);
        tuple_set_u64(t, 4, cr->call_time);
        tuple_set_u64(t, 5, cr->return_time);
        tuple_set_u64(t, 6, cr->branch_count);
        tuple_set_u64(t, 7, cr->call_ref);
        tuple_set_u64(t, 8, cr->return_ref);
        tuple_set_u64(t, 9, cr->cp->parent->db_id);
        tuple_set_s32(t, 10, cr->flags);

        call_object(tables->call_return_handler, t, "call_return_table");

        Py_DECREF(t);

        return 0;
}

static int python_process_call_return(struct call_return *cr, void *data)
{
        struct db_export *dbe = data;

        return db_export__call_return(dbe, cr);
}

static void python_process_general_event(struct perf_sample *sample,
                                         struct perf_evsel *evsel,
                                         struct addr_location *al)
{
        PyObject *handler, *t, *dict, *callchain, *dict_sample;
        static char handler_name[64];
        unsigned n = 0;

        /*
         * Use the MAX_FIELDS to make the function expandable, though
         * currently there is only one item for the tuple.
         */
        t = PyTuple_New(MAX_FIELDS);
        if (!t)
                Py_FatalError("couldn't create Python tuple");

        dict = PyDict_New();
        if (!dict)
                Py_FatalError("couldn't create Python dictionary");

        dict_sample = PyDict_New();
        if (!dict_sample)
                Py_FatalError("couldn't create Python dictionary");

        snprintf(handler_name, sizeof(handler_name), "%s", "process_event");

        handler = get_handler(handler_name);
        if (!handler)
                goto exit;

        pydict_set_item_string_decref(dict, "ev_name", PyString_FromString(perf_evsel__name(evsel)));
        pydict_set_item_string_decref(dict, "attr", PyString_FromStringAndSize(
                        (const char *)&evsel->attr, sizeof(evsel->attr)));

        pydict_set_item_string_decref(dict_sample, "pid",
                        PyInt_FromLong(sample->pid));
        pydict_set_item_string_decref(dict_sample, "tid",
                        PyInt_FromLong(sample->tid));
        pydict_set_item_string_decref(dict_sample, "cpu",
                        PyInt_FromLong(sample->cpu));
        pydict_set_item_string_decref(dict_sample, "ip",
                        PyLong_FromUnsignedLongLong(sample->ip));
        pydict_set_item_string_decref(dict_sample, "time",
                        PyLong_FromUnsignedLongLong(sample->time));
        pydict_set_item_string_decref(dict_sample, "period",
                        PyLong_FromUnsignedLongLong(sample->period));
        pydict_set_item_string_decref(dict, "sample", dict_sample);

        pydict_set_item_string_decref(dict, "raw_buf", PyString_FromStringAndSize(
                        (const char *)sample->raw_data, sample->raw_size));
        pydict_set_item_string_decref(dict, "comm",
                        PyString_FromString(thread__comm_str(al->thread)));
        if (al->map) {
                pydict_set_item_string_decref(dict, "dso",
                        PyString_FromString(al->map->dso->name));
        }
        if (al->sym) {
                pydict_set_item_string_decref(dict, "symbol",
                        PyString_FromString(al->sym->name));
        }

        /* ip unwinding */
        callchain = python_process_callchain(sample, evsel, al);
        pydict_set_item_string_decref(dict, "callchain", callchain);

        PyTuple_SetItem(t, n++, dict);
        if (_PyTuple_Resize(&t, n) == -1)
                Py_FatalError("error resizing Python tuple");

        call_object(handler, t, handler_name);
exit:
        Py_DECREF(dict);
        Py_DECREF(t);
}

static void python_process_event(union perf_event *event,
                                 struct perf_sample *sample,
                                 struct perf_evsel *evsel,
                                 struct addr_location *al)
{
        struct tables *tables = &tables_global;

        switch (evsel->attr.type) {
        case PERF_TYPE_TRACEPOINT:
                python_process_tracepoint(sample, evsel, al);
                break;
        /* Reserve for future process_hw/sw/raw APIs */
        default:
                if (tables->db_export_mode)
                        db_export__sample(&tables->dbe, event, sample, evsel, al);
                else
                        python_process_general_event(sample, evsel, al);
        }
}

static void get_handler_name(char *str, size_t size,
                             struct perf_evsel *evsel)
{
        char *p = str;

        scnprintf(str, size, "stat__%s", perf_evsel__name(evsel));

        while ((p = strchr(p, ':'))) {
                *p = '_';
                p++;
        }
}

static void
process_stat(struct perf_evsel *counter, int cpu, int thread, u64 tstamp,
             struct perf_counts_values *count)
{
        PyObject *handler, *t;
        static char handler_name[256];
        int n = 0;

        t = PyTuple_New(MAX_FIELDS);
        if (!t)
                Py_FatalError("couldn't create Python tuple");

        get_handler_name(handler_name, sizeof(handler_name),
                         counter);

        handler = get_handler(handler_name);
        if (!handler) {
                pr_debug("can't find python handler %s\n", handler_name);
                return;
        }

        PyTuple_SetItem(t, n++, PyInt_FromLong(cpu));
        PyTuple_SetItem(t, n++, PyInt_FromLong(thread));

        tuple_set_u64(t, n++, tstamp);
        tuple_set_u64(t, n++, count->val);
        tuple_set_u64(t, n++, count->ena);
        tuple_set_u64(t, n++, count->run);

        if (_PyTuple_Resize(&t, n) == -1)
                Py_FatalError("error resizing Python tuple");

        call_object(handler, t, handler_name);

        Py_DECREF(t);
}

static void python_process_stat(struct perf_stat_config *config,
                                struct perf_evsel *counter, u64 tstamp)
{
        struct thread_map *threads = counter->threads;
        struct cpu_map *cpus = counter->cpus;
        int cpu, thread;

        if (config->aggr_mode == AGGR_GLOBAL) {
                process_stat(counter, -1, -1, tstamp,
                             &counter->counts->aggr);
                return;
        }

        for (thread = 0; thread < threads->nr; thread++) {
                for (cpu = 0; cpu < cpus->nr; cpu++) {
                        process_stat(counter, cpus->map[cpu],
                                     thread_map__pid(threads, thread), tstamp,
                                     perf_counts(counter->counts, cpu, thread));
                }
        }
}

static void python_process_stat_interval(u64 tstamp)
{
        PyObject *handler, *t;
        static const char handler_name[] = "stat__interval";
        int n = 0;

        t = PyTuple_New(MAX_FIELDS);
        if (!t)
                Py_FatalError("couldn't create Python tuple");

        handler = get_handler(handler_name);
        if (!handler) {
                pr_debug("can't find python handler %s\n", handler_name);
                return;
        }

        tuple_set_u64(t, n++, tstamp);

        if (_PyTuple_Resize(&t, n) == -1)
                Py_FatalError("error resizing Python tuple");

        call_object(handler, t, handler_name);

        Py_DECREF(t);
}

static int run_start_sub(void)
{
        main_module = PyImport_AddModule("__main__");
        if (main_module == NULL)
                return -1;
        Py_INCREF(main_module);

        main_dict = PyModule_GetDict(main_module);
        if (main_dict == NULL)
                goto error;
        Py_INCREF(main_dict);

        try_call_object("trace_begin", NULL);

        return 0;

error:
        Py_XDECREF(main_dict);
        Py_XDECREF(main_module);
        return -1;
}

#define SET_TABLE_HANDLER_(name, handler_name, table_name) do {         \
        tables->handler_name = get_handler(#table_name);                \
        if (tables->handler_name)                                       \
                tables->dbe.export_ ## name = python_export_ ## name;   \
} while (0)

#define SET_TABLE_HANDLER(name) \
        SET_TABLE_HANDLER_(name, name ## _handler, name ## _table)

static void set_table_handlers(struct tables *tables)
{
        const char *perf_db_export_mode = "perf_db_export_mode";
        const char *perf_db_export_calls = "perf_db_export_calls";
        const char *perf_db_export_callchains = "perf_db_export_callchains";
        PyObject *db_export_mode, *db_export_calls, *db_export_callchains;
        bool export_calls = false;
        bool export_callchains = false;
        int ret;

        memset(tables, 0, sizeof(struct tables));
        if (db_export__init(&tables->dbe))
                Py_FatalError("failed to initialize export");

        db_export_mode = PyDict_GetItemString(main_dict, perf_db_export_mode);
        if (!db_export_mode)
                return;

        ret = PyObject_IsTrue(db_export_mode);
        if (ret == -1)
                handler_call_die(perf_db_export_mode);
        if (!ret)
                return;

        /* handle export calls */
        tables->dbe.crp = NULL;
        db_export_calls = PyDict_GetItemString(main_dict, perf_db_export_calls);
        if (db_export_calls) {
                ret = PyObject_IsTrue(db_export_calls);
                if (ret == -1)
                        handler_call_die(perf_db_export_calls);
                export_calls = !!ret;
        }

        if (export_calls) {
                tables->dbe.crp =
                        call_return_processor__new(python_process_call_return,
                                                   &tables->dbe);
                if (!tables->dbe.crp)
                        Py_FatalError("failed to create calls processor");
        }

        /* handle export callchains */
        tables->dbe.cpr = NULL;
        db_export_callchains = PyDict_GetItemString(main_dict,
                                                    perf_db_export_callchains);
        if (db_export_callchains) {
                ret = PyObject_IsTrue(db_export_callchains);
                if (ret == -1)
                        handler_call_die(perf_db_export_callchains);
                export_callchains = !!ret;
        }

        if (export_callchains) {
                /*
                 * Attempt to use the call path root from the call return
                 * processor, if the call return processor is in use. Otherwise,
                 * we allocate a new call path root. This prevents exporting
                 * duplicate call path ids when both are in use simultaniously.
                 */
                if (tables->dbe.crp)
                        tables->dbe.cpr = tables->dbe.crp->cpr;
                else
                        tables->dbe.cpr = call_path_root__new();

                if (!tables->dbe.cpr)
                        Py_FatalError("failed to create call path root");
        }

        tables->db_export_mode = true;
        /*
         * Reserve per symbol space for symbol->db_id via symbol__priv()
         */
        symbol_conf.priv_size = sizeof(u64);

        SET_TABLE_HANDLER(evsel);
        SET_TABLE_HANDLER(machine);
        SET_TABLE_HANDLER(thread);
        SET_TABLE_HANDLER(comm);
        SET_TABLE_HANDLER(comm_thread);
        SET_TABLE_HANDLER(dso);
        SET_TABLE_HANDLER(symbol);
        SET_TABLE_HANDLER(branch_type);
        SET_TABLE_HANDLER(sample);
        SET_TABLE_HANDLER(call_path);
        SET_TABLE_HANDLER(call_return);
}

/*
 * Start trace script
 */
static int python_start_script(const char *script, int argc, const char **argv)
{
        struct tables *tables = &tables_global;
        const char **command_line;
        char buf[PATH_MAX];
        int i, err = 0;
        FILE *fp;

        command_line = malloc((argc + 1) * sizeof(const char *));
        command_line[0] = script;
        for (i = 1; i < argc + 1; i++)
                command_line[i] = argv[i - 1];

        Py_Initialize();

        initperf_trace_context();

        PySys_SetArgv(argc + 1, (char **)command_line);

        fp = fopen(script, "r");
        if (!fp) {
                sprintf(buf, "Can't open python script \"%s\"", script);
                perror(buf);
                err = -1;
                goto error;
        }

        err = PyRun_SimpleFile(fp, script);
        if (err) {
                fprintf(stderr, "Error running python script %s\n", script);
                goto error;
        }

        err = run_start_sub();
        if (err) {
                fprintf(stderr, "Error starting python script %s\n", script);
                goto error;
        }

        set_table_handlers(tables);

        if (tables->db_export_mode) {
                err = db_export__branch_types(&tables->dbe);
                if (err)
                        goto error;
        }

        free(command_line);

        return err;
error:
        Py_Finalize();
        free(command_line);

        return err;
}

static int python_flush_script(void)
{
        struct tables *tables = &tables_global;

        return db_export__flush(&tables->dbe);
}

/*
 * Stop trace script
 */
static int python_stop_script(void)
{
        struct tables *tables = &tables_global;

        try_call_object("trace_end", NULL);

        db_export__exit(&tables->dbe);

        Py_XDECREF(main_dict);
        Py_XDECREF(main_module);
        Py_Finalize();

        return 0;
}

static int python_generate_script(struct pevent *pevent, const char *outfile)
{
        struct event_format *event = NULL;
        struct format_field *f;
        char fname[PATH_MAX];
        int not_first, count;
        FILE *ofp;

        sprintf(fname, "%s.py", outfile);
        ofp = fopen(fname, "w");
        if (ofp == NULL) {
                fprintf(stderr, "couldn't open %s\n", fname);
                return -1;
        }
        fprintf(ofp, "# perf script event handlers, "
                "generated by perf script -g python\n");

        fprintf(ofp, "# Licensed under the terms of the GNU GPL"
                " License version 2\n\n");

        fprintf(ofp, "# The common_* event handler fields are the most useful "
                "fields common to\n");

        fprintf(ofp, "# all events.  They don't necessarily correspond to "
                "the 'common_*' fields\n");

        fprintf(ofp, "# in the format files.  Those fields not available as "
                "handler params can\n");

        fprintf(ofp, "# be retrieved using Python functions of the form "
                "common_*(context).\n");

        fprintf(ofp, "# See the perf-trace-python Documentation for the list "
                "of available functions.\n\n");

        fprintf(ofp, "import os\n");
        fprintf(ofp, "import sys\n\n");

        fprintf(ofp, "sys.path.append(os.environ['PERF_EXEC_PATH'] + \\\n");
        fprintf(ofp, "\t'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')\n");
        fprintf(ofp, "\nfrom perf_trace_context import *\n");
        fprintf(ofp, "from Core import *\n\n\n");

        fprintf(ofp, "def trace_begin():\n");
        fprintf(ofp, "\tprint \"in trace_begin\"\n\n");

        fprintf(ofp, "def trace_end():\n");
        fprintf(ofp, "\tprint \"in trace_end\"\n\n");

        while ((event = trace_find_next_event(pevent, event))) {
                fprintf(ofp, "def %s__%s(", event->system, event->name);
                fprintf(ofp, "event_name, ");
                fprintf(ofp, "context, ");
                fprintf(ofp, "common_cpu,\n");
                fprintf(ofp, "\tcommon_secs, ");
                fprintf(ofp, "common_nsecs, ");
                fprintf(ofp, "common_pid, ");
                fprintf(ofp, "common_comm,\n\t");
                fprintf(ofp, "common_callchain, ");

                not_first = 0;
                count = 0;

                for (f = event->format.fields; f; f = f->next) {
                        if (not_first++)
                                fprintf(ofp, ", ");
                        if (++count % 5 == 0)
                                fprintf(ofp, "\n\t");

                        fprintf(ofp, "%s", f->name);
                }
                fprintf(ofp, "):\n");

                fprintf(ofp, "\t\tprint_header(event_name, common_cpu, "
                        "common_secs, common_nsecs,\n\t\t\t"
                        "common_pid, common_comm)\n\n");

                fprintf(ofp, "\t\tprint \"");

                not_first = 0;
                count = 0;

                for (f = event->format.fields; f; f = f->next) {
                        if (not_first++)
                                fprintf(ofp, ", ");
                        if (count && count % 3 == 0) {
                                fprintf(ofp, "\" \\\n\t\t\"");
                        }
                        count++;

                        fprintf(ofp, "%s=", f->name);
                        if (f->flags & FIELD_IS_STRING ||
                            f->flags & FIELD_IS_FLAG ||
                            f->flags & FIELD_IS_ARRAY ||
                            f->flags & FIELD_IS_SYMBOLIC)
                                fprintf(ofp, "%%s");
                        else if (f->flags & FIELD_IS_SIGNED)
                                fprintf(ofp, "%%d");
                        else
                                fprintf(ofp, "%%u");
                }

                fprintf(ofp, "\" %% \\\n\t\t(");

                not_first = 0;
                count = 0;

                for (f = event->format.fields; f; f = f->next) {
                        if (not_first++)
                                fprintf(ofp, ", ");

                        if (++count % 5 == 0)
                                fprintf(ofp, "\n\t\t");

                        if (f->flags & FIELD_IS_FLAG) {
                                if ((count - 1) % 5 != 0) {
                                        fprintf(ofp, "\n\t\t");
                                        count = 4;
                                }
                                fprintf(ofp, "flag_str(\"");
                                fprintf(ofp, "%s__%s\", ", event->system,
                                        event->name);
                                fprintf(ofp, "\"%s\", %s)", f->name,
                                        f->name);
                        } else if (f->flags & FIELD_IS_SYMBOLIC) {
                                if ((count - 1) % 5 != 0) {
                                        fprintf(ofp, "\n\t\t");
                                        count = 4;
                                }
                                fprintf(ofp, "symbol_str(\"");
                                fprintf(ofp, "%s__%s\", ", event->system,
                                        event->name);
                                fprintf(ofp, "\"%s\", %s)", f->name,
                                        f->name);
                        } else
                                fprintf(ofp, "%s", f->name);
                }

                fprintf(ofp, ")\n\n");

                fprintf(ofp, "\t\tfor node in common_callchain:");
                fprintf(ofp, "\n\t\t\tif 'sym' in node:");
                fprintf(ofp, "\n\t\t\t\tprint \"\\t[%%x] %%s\" %% (node['ip'], node['sym']['name'])");
                fprintf(ofp, "\n\t\t\telse:");
                fprintf(ofp, "\n\t\t\t\tprint \"\t[%%x]\" %% (node['ip'])\n\n");
                fprintf(ofp, "\t\tprint \"\\n\"\n\n");

        }

        fprintf(ofp, "def trace_unhandled(event_name, context, "
                "event_fields_dict):\n");

        fprintf(ofp, "\t\tprint ' '.join(['%%s=%%s'%%(k,str(v))"
                "for k,v in sorted(event_fields_dict.items())])\n\n");

        fprintf(ofp, "def print_header("
                "event_name, cpu, secs, nsecs, pid, comm):\n"
                "\tprint \"%%-20s %%5u %%05u.%%09u %%8u %%-20s \" %% \\\n\t"
                "(event_name, cpu, secs, nsecs, pid, comm),\n");

        fclose(ofp);

        fprintf(stderr, "generated Python script: %s\n", fname);

        return 0;
}

struct scripting_ops python_scripting_ops = {
        .name                   = "Python",
        .start_script           = python_start_script,
        .flush_script           = python_flush_script,
        .stop_script            = python_stop_script,
        .process_event          = python_process_event,
        .process_stat           = python_process_stat,
        .process_stat_interval  = python_process_stat_interval,
        .generate_script        = python_generate_script,
};