/*
 * Copyright 2009, Intel Corporation
 * Copyright 2009, Sun Microsystems, Inc
 *
 * This file is part of PowerTOP
 *
 * This program file 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; version 2 of the License.
 *
 * 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 in a file named COPYING; if not, write to the
 * Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301 USA
 *
 * Authors:
 *      Arjan van de Ven <arjan@linux.intel.com>
 *      Eric C Saxe <eric.saxe@sun.com>
 *      Aubrey Li <aubrey.li@intel.com>
 */

/*
 * GPL Disclaimer
 *
 * For the avoidance of doubt, except that if any license choice other
 * than GPL or LGPL is available it will apply instead, Sun elects to
 * use only the General Public License version 2 (GPLv2) at this time
 * for any software where a choice of GPL license versions is made
 * available with the language indicating that GPLv2 or any later
 * version may be used, or where a choice of which version of the GPL
 * is applied is otherwise unspecified.
 */

#include <string.h>
#include <stdlib.h>
#include <dtrace.h>
#include "powertop.h"

static dtrace_hdl_t *dtp;
static event_info_t *event;

/*ARGSUSED*/
static int
pt_events_walk(const dtrace_aggdata_t *data, void *arg)
{
        dtrace_aggdesc_t        *aggdesc = data->dtada_desc;
        dtrace_recdesc_t        *rec1, *rec2, *rec3;
        dtrace_syminfo_t        dts;
        GElf_Sym                sym;
        uint64_t                offender_addr;
        uint64_t                n = 0;
        int32_t                 *instance, *offender_cpu;
        int                     i;
        char                    *offense_name;

        if (g_top_events >= EVENT_NUM_MAX)
                return (0);

        rec1 = &aggdesc->dtagd_rec[1];
        rec2 = &aggdesc->dtagd_rec[2];

        /*
         * Report interrupts
         */
        if (strcmp(aggdesc->dtagd_name, "interrupts") == 0) {
                offense_name = data->dtada_data + rec1->dtrd_offset;

                /* LINTED - alignment */
                instance = (int32_t *)(data->dtada_data + rec2->dtrd_offset);
                (void) snprintf((char *)(event->offender_name),
                    EVENT_NAME_MAX, "%s", "<interrupt>");
                (void) snprintf((char *)(event->offense_name),
                    EVENT_NAME_MAX, "%s#%d", offense_name, *instance);
        /*
         * Report kernel events
         */
        } else if (strcmp(aggdesc->dtagd_name, "events_k") == 0) {

                (void) snprintf((char *)(event->offender_name),
                    EVENT_NAME_MAX, "%s", "<kernel>");

                /*
                 * Casting offender_addr to the wrong type will cause
                 * dtrace_lookup_by_addr to return 0 and the report
                 * to show an address instead of a name.
                 */
                switch (g_bit_depth) {
                case 32:
                        /* LINTED - alignment */
                        offender_addr = *(uint32_t *)(data->dtada_data +
                            rec1->dtrd_offset);
                        break;
                case 64:
                        /* LINTED - alignment */
                        offender_addr = *(uint64_t *)(data->dtada_data +
                            rec1->dtrd_offset);
                        break;
                }

                /*
                 * We have the address of the kernel callout.
                 * Try to resolve it into a meaningful symbol
                 */
                if (offender_addr != 0 && dtrace_lookup_by_addr(dtp,
                    offender_addr, &sym, &dts) == 0) {
                        (void) snprintf((char *)(event->offense_name),
                            EVENT_NAME_MAX, "%s`%s", dts.dts_object,
                            dts.dts_name);
                } else {
                        (void) snprintf((char *)(event->offense_name),
                            EVENT_NAME_MAX, "0x%llx", offender_addr);
                }
        /*
         * Report user events
         */
        } else if (strcmp(aggdesc->dtagd_name, "events_u") == 0) {
                offense_name = data->dtada_data + rec1->dtrd_offset;

                (void) snprintf((char *)(event->offender_name),
                    EVENT_NAME_MAX, "%s", offense_name);
                (void) snprintf((char *)(event->offense_name),
                    EVENT_NAME_MAX, "<scheduled timeout expiration>");
        /*
         * Report cross calls
         */
        } else if (strcmp(aggdesc->dtagd_name, "events_x") == 0) {
                offense_name = data->dtada_data + rec1->dtrd_offset;

                (void) snprintf((char *)(event->offender_name),
                    EVENT_NAME_MAX, "%s", offense_name);

                switch (g_bit_depth) {
                case 32:
                        /* LINTED - alignment */
                        offender_addr = *(uint32_t *)(data->dtada_data +
                            rec2->dtrd_offset);
                        break;
                case 64:
                        /* LINTED - alignment */
                        offender_addr = *(uint64_t *)(data->dtada_data +
                            rec2->dtrd_offset);
                        break;
                }

                /*
                 * Try to resolve the address of the cross call function.
                 */
                if (offender_addr != 0 && dtrace_lookup_by_addr(dtp,
                    offender_addr, &sym, &dts) == 0) {
                        (void) snprintf((char *)(event->offense_name),
                            EVENT_NAME_MAX, "<xcalls> %s`%s",
                            dts.dts_object, dts.dts_name);
                } else {
                        (void) snprintf((char *)(event->offense_name),
                            EVENT_NAME_MAX, "<xcalls>");
                }
        /*
         * Report cross calls from other CPUs than the one we're observing
         * with the -C option
         */
        } else if (strcmp(aggdesc->dtagd_name, "events_xc") == 0) {
                rec3 = &aggdesc->dtagd_rec[3];
                offense_name = data->dtada_data + rec1->dtrd_offset;

                (void) snprintf((char *)(event->offender_name),
                    EVENT_NAME_MAX, "%s", offense_name);

                switch (g_bit_depth) {
                case 32:
                        /* LINTED - alignment */
                        offender_addr = *(uint32_t *)(data->dtada_data +
                            rec2->dtrd_offset);
                        break;
                case 64:
                        /* LINTED - alignment */
                        offender_addr = *(uint64_t *)(data->dtada_data +
                            rec2->dtrd_offset);
                        break;
                }
                /* LINTED - alignment */
                offender_cpu = (int32_t *)(data->dtada_data +
                    rec3->dtrd_offset);

                /*
                 * Try to resolve the address of the cross call function.
                 */
                if (offender_addr != 0 && dtrace_lookup_by_addr(dtp,
                    offender_addr, &sym, &dts) == 0) {
                        (void) snprintf((char *)(event->offense_name),
                            EVENT_NAME_MAX, "<xcalls> %s`%s (CPU %d)",
                            dts.dts_object, dts.dts_name, *offender_cpu);
                } else {
                        (void) snprintf((char *)(event->offense_name),
                            EVENT_NAME_MAX, "<xcalls> (CPU %d)",
                            *offender_cpu);
                }
        /*
         * Report unknown events
         */
        } else {
                (void) snprintf((char *)(event->offender_name),
                    EVENT_NAME_MAX, "%s", "<unknown>");
                (void) snprintf((char *)(event->offense_name),
                    EVENT_NAME_MAX, "%s", "<unknown>");
        }

        for (i = 0; i < g_ncpus; i++) {
                /* LINTED - alignment */
                n += *((uint64_t *)(data->dtada_percpu[i]));
        }

        event->total_count = n;

        event++;
        g_top_events++;

        return (DTRACE_AGGWALK_NEXT);
}

int
pt_events_stat_prepare(void)
{
        dtrace_prog_t           *prog;
        dtrace_proginfo_t       info;
        dtrace_optval_t         statustime;
        int                     err;
        char                    *prog_ptr;

        event = g_event_info;

        if ((dtp = dtrace_open(DTRACE_VERSION, 0, &err)) == NULL) {
                pt_error("cannot open dtrace library for the event report: "
                    "%s\n", dtrace_errmsg(NULL, err));
                return (-1);
        }

        /*
         * Execute different scripts (defined in the platform specific file)
         * depending on user specified options.
         */
        if (PT_ON_VERBOSE) {
                prog_ptr = (char *)g_dtp_events_v;
        } else {
                if (PT_ON_CPU)
                        prog_ptr = (char *)g_dtp_events_c;
                else
                        prog_ptr = (char *)g_dtp_events;
        }

        if ((prog = dtrace_program_strcompile(dtp, prog_ptr,
            DTRACE_PROBESPEC_NAME, 0, g_argc, g_argv)) == NULL) {
                pt_error("failed to compile the event report program\n");
                return (dtrace_errno(dtp));
        }

        if (dtrace_program_exec(dtp, prog, &info) == -1) {
                pt_error("failed to enable probes for the event report\n");
                return (dtrace_errno(dtp));
        }

        if (dtrace_setopt(dtp, "aggsize", "128k") == -1) {
                pt_error("failed to set 'aggsize' for the event report\n");
                return (dtrace_errno(dtp));
        }

        if (dtrace_setopt(dtp, "aggrate", "0") == -1) {
                pt_error("failed to set 'aggrate' for the event report\n");
                return (dtrace_errno(dtp));
        }

        if (dtrace_setopt(dtp, "aggpercpu", 0) == -1) {
                pt_error("failed to set 'aggpercpu' for the event report\n");
                return (dtrace_errno(dtp));
        }

        if (dtrace_go(dtp) != 0) {
                pt_error("failed to start the event report observation\n");
                return (dtrace_errno(dtp));
        }

        if (dtrace_getopt(dtp, "statusrate", &statustime) == -1) {
                pt_error("failed to get 'statusrate' for the event report\n");
                return (dtrace_errno(dtp));
        }

        return (0);
}

int
pt_events_stat_collect(void)
{
        g_top_events = 0;
        event = g_event_info;

        if (dtrace_status(dtp) == -1)
                return (-1);

        if (dtrace_aggregate_snap(dtp) != 0)
                pt_error("failed to collect data for the event report\n");

        if (dtrace_aggregate_walk_keyvarsorted(dtp, pt_events_walk, NULL) != 0)
                pt_error("failed to sort data for the event report\n");

        dtrace_aggregate_clear(dtp);

        return (0);
}