powertop/common/events.c

/*
 * 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 != NULL && 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 != NULL && 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 != NULL && 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);
}