static void
reply_msacc(void *vmsaccrp)
{
ErtsMsAcc *msacc = ERTS_MSACC_TSD_GET();
ErtsMSAccReq *msaccrp = (ErtsMSAccReq *) vmsaccrp;
ASSERT(!msacc || !msacc->unmanaged);
if (msaccrp->action == ERTS_MSACC_ENABLE && !msacc) {
msacc = get_msacc();
msacc->perf_counter = erts_sys_perf_counter();
msacc->state = ERTS_MSACC_STATE_OTHER;
ERTS_MSACC_TSD_SET(msacc);
} else if (msaccrp->action == ERTS_MSACC_DISABLE && msacc) {
ERTS_MSACC_TSD_SET(NULL);
} else if (msaccrp->action == ERTS_MSACC_RESET) {
msacc = msacc ? msacc : get_msacc();
erts_msacc_reset(msacc);
} else if (msaccrp->action == ERTS_MSACC_GATHER && !msacc) {
msacc = get_msacc();
}
ASSERT(!msacc || !msacc->unmanaged);
send_reply(msacc, msaccrp);
erts_proc_dec_refc(msaccrp->proc);
if (erts_smp_atomic32_dec_read_nob(&msaccrp->refc) == 0)
erts_free(ERTS_ALC_T_MSACC, vmsaccrp);
}
void erts_msacc_init_thread(char *type, int id, int managed) {
ErtsMsAcc *msacc;
msacc = erts_alloc(ERTS_ALC_T_MSACC, sizeof(ErtsMsAcc) +
sizeof(ErtsMsAccPerfCntr) * ERTS_MSACC_STATE_COUNT);
msacc->type = strdup(type);
msacc->id = make_small(id);
msacc->unmanaged = !managed;
msacc->tid = erts_thr_self();
msacc->perf_counter = 0;
#ifdef USE_THREADS
erts_rwmtx_rwlock(&msacc_mutex);
if (!managed) {
erts_mtx_init(&msacc->mtx,"msacc_unmanaged_mutex");
msacc->next = msacc_unmanaged;
msacc_unmanaged = msacc;
msacc_unmanaged_count++;
ERTS_MSACC_TSD_SET(msacc);
} else {
msacc->next = msacc_managed;
msacc_managed = msacc;
}
erts_rwmtx_rwunlock(&msacc_mutex);
#else
msacc_managed = msacc;
#endif
erts_msacc_reset(msacc);
#ifdef ERTS_MSACC_ALWAYS_ON
ERTS_MSACC_TSD_SET(msacc);
msacc->perf_counter = erts_sys_perf_counter();
msacc->state = ERTS_MSACC_STATE_OTHER;
#endif
}
/*
* This function is responsible for enabling, disabling, resetting and
* gathering data related to microstate accounting.
*
* Managed threads and unmanaged threads are handled differently.
* - managed threads get a misc_aux job telling them to switch on msacc
* - unmanaged have some fields protected by a mutex that has to be taken
* before any values can be updated
*
* For performance reasons there is also a global value erts_msacc_enabled
* that controls the state of all threads. Statistics gathering is only on
* if erts_msacc_enabled && msacc is true.
*/
Eterm
erts_msacc_request(Process *c_p, int action, Eterm *threads)
{
#ifdef ERTS_ENABLE_MSACC
ErtsMsAcc *msacc = ERTS_MSACC_TSD_GET();
ErtsSchedulerData *esdp = erts_proc_sched_data(c_p);
Eterm ref;
ErtsMSAccReq *msaccrp;
Eterm *hp;
#ifdef ERTS_MSACC_ALWAYS_ON
if (action == ERTS_MSACC_ENABLE || action == ERTS_MSACC_DISABLE)
return THE_NON_VALUE;
#else
/* take care of double enable, and double disable here */
if (msacc && action == ERTS_MSACC_ENABLE) {
return THE_NON_VALUE;
} else if (!msacc && action == ERTS_MSACC_DISABLE) {
return THE_NON_VALUE;
}
#endif
ref = erts_make_ref(c_p);
msaccrp = erts_alloc(ERTS_ALC_T_MSACC, sizeof(ErtsMSAccReq));
hp = &msaccrp->ref_heap[0];
msaccrp->action = action;
msaccrp->proc = c_p;
msaccrp->ref = STORE_NC(&hp, NULL, ref);
msaccrp->req_sched = esdp->no;
#ifdef ERTS_SMP
*threads = erts_no_schedulers;
*threads += 1; /* aux thread */
#else
*threads = 1;
#endif
erts_smp_atomic32_init_nob(&msaccrp->refc,(erts_aint32_t)*threads);
erts_proc_add_refc(c_p, *threads);
if (erts_no_schedulers > 1)
erts_schedule_multi_misc_aux_work(1,
erts_no_schedulers,
reply_msacc,
(void *) msaccrp);
#ifdef ERTS_SMP
/* aux thread */
erts_schedule_misc_aux_work(0, reply_msacc, (void *) msaccrp);
#endif
#ifdef USE_THREADS
/* Manage unmanaged threads */
switch (action) {
case ERTS_MSACC_GATHER: {
Uint unmanaged_count;
ErtsMsAcc *msacc, **unmanaged;
int i = 0;
/* we copy a list of pointers here so that we do not have to have
the msacc_mutex when sending messages */
erts_rwmtx_rlock(&msacc_mutex);
unmanaged_count = msacc_unmanaged_count;
unmanaged = erts_alloc(ERTS_ALC_T_MSACC,
sizeof(ErtsMsAcc*)*unmanaged_count);
for (i = 0, msacc = msacc_unmanaged;
i < unmanaged_count;
i++, msacc = msacc->next) {
unmanaged[i] = msacc;
}
erts_rwmtx_runlock(&msacc_mutex);
for (i = 0; i < unmanaged_count; i++) {
erts_mtx_lock(&unmanaged[i]->mtx);
if (unmanaged[i]->perf_counter) {
ErtsSysPerfCounter perf_counter;
/* if enabled update stats */
perf_counter = erts_sys_perf_counter();
unmanaged[i]->perf_counters[unmanaged[i]->state] +=
perf_counter - unmanaged[i]->perf_counter;
unmanaged[i]->perf_counter = perf_counter;
}
erts_mtx_unlock(&unmanaged[i]->mtx);
send_reply(unmanaged[i],msaccrp);
}
erts_free(ERTS_ALC_T_MSACC,unmanaged);
/* We have just sent unmanaged_count messages, so bump no of threads */
*threads += unmanaged_count;
break;
}
case ERTS_MSACC_RESET: {
ErtsMsAcc *msacc;
erts_rwmtx_rlock(&msacc_mutex);
for (msacc = msacc_unmanaged; msacc != NULL; msacc = msacc->next)
erts_msacc_reset(msacc);
erts_rwmtx_runlock(&msacc_mutex);
break;
}
case ERTS_MSACC_ENABLE: {
erts_rwmtx_rlock(&msacc_mutex);
for (msacc = msacc_unmanaged; msacc != NULL; msacc = msacc->next) {
erts_mtx_lock(&msacc->mtx);
msacc->perf_counter = erts_sys_perf_counter();
/* we assume the unmanaged thread is sleeping */
msacc->state = ERTS_MSACC_STATE_SLEEP;
erts_mtx_unlock(&msacc->mtx);
}
erts_rwmtx_runlock(&msacc_mutex);
break;
}
case ERTS_MSACC_DISABLE: {
ErtsSysPerfCounter perf_counter;
erts_rwmtx_rlock(&msacc_mutex);
/* make sure to update stats with latest results */
for (msacc = msacc_unmanaged; msacc != NULL; msacc = msacc->next) {
erts_mtx_lock(&msacc->mtx);
perf_counter = erts_sys_perf_counter();
msacc->perf_counters[msacc->state] += perf_counter - msacc->perf_counter;
msacc->perf_counter = 0;
erts_mtx_unlock(&msacc->mtx);
}
erts_rwmtx_runlock(&msacc_mutex);
break;
}
default: { ASSERT(0); }
}
#endif
*threads = make_small(*threads);
reply_msacc((void *) msaccrp);
#ifndef ERTS_MSACC_ALWAYS_ON
/* enable/disable the global value */
if (action == ERTS_MSACC_ENABLE) {
erts_msacc_enabled = 1;
} else if (action == ERTS_MSACC_DISABLE) {
erts_msacc_enabled = 0;
}
#endif
return ref;
#else
return THE_NON_VALUE;
#endif
}
