runtime/dyninst/stat_runtime.h - systemtap

Data types defined

Functions defined

Macros defined

Source code

/* -*- linux-c -*-
* Stat Runtime Functions
* Copyright (C) 2012 Red Hat Inc.
*
* This file is part of systemtap, and is free software.  You can
* redistribute it and/or modify it under the terms of the GNU General
* Public License (GPL); either version 2, or (at your option) any
* later version.
*/

#ifndef _STAPDYN_STAT_RUNTIME_H_
‌#define _STAPDYN_STAT_RUNTIME_H_

#include <pthread.h>
#include <unistd.h>
#include <sched.h>

#include "offptr.h"

#ifdef NEED_STAT_LOCKS
‌#define STAT_LOCK(sd)        pthread_mutex_lock(&(sd)->lock)
‌#define STAT_UNLOCK(sd)        pthread_mutex_unlock(&(sd)->lock)
#else
‌#define STAT_LOCK(sd)        do {} while (0)
‌#define STAT_UNLOCK(sd)        do {} while (0)
#endif

‌static int STAT_GET_CPU(void)
{
    return _stp_runtime_get_data_index();
}

‌#define STAT_PUT_CPU()    do {} while (0)

/** Stat struct. Maps do not need this */
‌typedef struct _Stat {
    struct _Hist hist;

    /* aggregated data */
    offptr_t oagg;

    /* The stat data is a "per-cpu" array.  */
        offptr_t osd[];
‌} *Stat;

‌static Stat _stp_stat_alloc(size_t stat_data_size)
{
    int i;
    void *mem;
    Stat st;

    size_t stat_size = sizeof(struct _Stat)
        + sizeof(offptr_t) * _stp_runtime_num_contexts;

    size_t total_size = stat_size +
        stat_data_size * (_stp_runtime_num_contexts + 1);

    if (stat_data_size < sizeof(stat_data))
        return NULL;

    /* NB: This is done as one big allocation, then assigning offptrs to
     * each sub-piece.  (See _stp_pmap_new for more explanation) */
    st = mem = _stp_shm_zalloc(total_size);
    if (st == NULL)
        return NULL;

    mem += stat_size;
    offptr_set(&st->oagg, mem);

    for_each_possible_cpu(i) {
        mem += stat_data_size;
        offptr_set(&st->osd[i], mem);
    }

    return st;
}

‌static void _stp_stat_free(Stat st)
{
    _stp_shm_free(st);
}

‌static inline stat_data* _stp_stat_get_agg(Stat st)
{
    return offptr_get(&st->oagg);
}

‌static inline stat_data* _stp_stat_per_cpu_ptr(Stat st, int cpu)
{
    return offptr_get(&st->osd[cpu]);
}

‌static int _stp_stat_initialize_locks(Stat st)
{
#ifdef NEED_STAT_LOCKS
    int i, rc;
    stat_data *sdp;
    for_each_possible_cpu(i) {
        sdp = _stp_stat_per_cpu_ptr (st, i);

        if ((rc = stp_pthread_mutex_init_shared(&sdp->lock))
            != 0) {
            return rc;
        }
    }
    sdp = _stp_stat_get_agg (st);
    if ((rc = stp_pthread_mutex_init_shared(&sdp->lock)) != 0) {
        _stp_error("Couldn't initialize stat mutex: %d\n", rc);
    }
    return rc;
#else
    return 0;
#endif
}

‌static void _stp_stat_destroy_locks(Stat st)
{
#ifdef NEED_STAT_LOCKS
    int i;
    stat_data *sdp;
    for_each_possible_cpu(i) {
        sdp = _stp_stat_per_cpu_ptr(st, i);
        (void)pthread_mutex_destroy(&sdp->lock);
    }
    sdp = _stp_stat_get_agg (st);
    (void)pthread_mutex_destroy(&sdp->lock);
#endif
}

#endif /* _STAPDYN_STAT_RUNTIME_H_ */