// Sampling only a-mode registers
void perfctr_cpu_sample(struct perfctr_cpu_state *state)
{
unsigned int i, cstatus, nractrs;
struct perfctr_low_ctrs now;
int cpu_id;
cpu_id = hard_smp_processor_id() / 4;
spin_lock (&pmc_resource[cpu_id].lock);
if ( pmc_resource[cpu_id].current_thread != netlogic_thr_id() ) {
// printk (KERN_INFO "PMCounters do not belong to this process[%d]\n", current->pid);
spin_unlock (&pmc_resource[cpu_id].lock);
return;
}
spin_unlock (&pmc_resource[cpu_id].lock);
perfctr_cpu_read_counters(state, &now); // reads only a-mode registers
cstatus = state->cstatus;
if (perfctr_cstatus_has_tsc(cstatus)) {
state->tsc_sum += now.tsc - state->tsc_start;
// one needs to update the start status as we continue to gather
// statistics without interruption
state->tsc_start = now.tsc;
}
nractrs = perfctr_cstatus_nractrs(cstatus);
for(i = 0; i < nractrs; ++i) {
state->pmc[i].sum += now.pmc[i] - state->pmc[i].start;
state->pmc[i].start = now.pmc[i];
}
}
inline void perfctr_cpu_suspend(struct perfctr_cpu_state *state)
{
unsigned int i, cstatus, nractrs;
struct perfctr_low_ctrs now;
int cpu_id;
cpu_id = hard_smp_processor_id() / 4;
spin_lock (&pmc_resource[cpu_id].lock);
if ( pmc_resource[cpu_id].current_thread != netlogic_thr_id() ) {
// printk (KERN_INFO "PMCounters do not belong to this process[%d]\n", current->pid);
spin_unlock (&pmc_resource[cpu_id].lock);
return;
}
pmc_resource[cpu_id].current_thread = -1;
spin_unlock (&pmc_resource[cpu_id].lock);
// To prevent polluting the numbers, can we freeze the counters
// here, as early as possible ?
if (perfctr_cstatus_has_ictrs(state->cstatus)) {
perfctr_cpu_isuspend(state);
}
perfctr_cpu_read_counters(state, &now);
cstatus = state->cstatus;
if (perfctr_cstatus_has_tsc(cstatus)) {
state->tsc_sum += now.tsc - state->tsc_start;
}
nractrs = perfctr_cstatus_nractrs(cstatus);
for(i = 0; i < nractrs; ++i) {
state->pmc[i].sum += now.pmc[i] - state->pmc[i].start;
}
}
static int nlm_common_pmc_owned(void)
{
int cpu_id ;
unsigned long flags;
int thr_id;
/* Allow only thread0 in each core to set perfcounter events */
spin_lock_irqsave(&nlm_common_perf_lock, flags);
thr_id = netlogic_thr_id();
if(thr_id) {
spin_unlock_irqrestore(&nlm_common_perf_lock, flags);
return 1;
}
cpu_id = netlogic_cpu_id();
if(nlm_common_perf_core_setup[cpu_id] == -1) {
nlm_common_perf_core_setup[cpu_id] = hard_smp_processor_id();
spin_unlock_irqrestore(&nlm_common_perf_lock, flags);
return 0;
}
if(nlm_common_perf_core_setup[cpu_id] == hard_smp_processor_id()) {
spin_unlock_irqrestore(&nlm_common_perf_lock, flags);
return 0;
}
spin_unlock_irqrestore(&nlm_common_perf_lock, flags);
return 1;
}
inline void perfctr_cpu_resume(struct perfctr_cpu_state *state)
{
int cpu_id;
cpu_id = hard_smp_processor_id() / 4;
spin_lock (&pmc_resource[cpu_id].lock);
if ( pmc_resource[cpu_id].current_thread != -1 ) {
// printk (KERN_INFO "PMCounters unavailable for process %d\n", current->pid);
spin_unlock (&pmc_resource[cpu_id].lock);
return;
}
pmc_resource[cpu_id].current_thread = netlogic_thr_id();
spin_unlock (&pmc_resource[cpu_id].lock);
if (perfctr_cstatus_has_ictrs(state->cstatus)) {
perfctr_cpu_iresume(state);
}
// the counters are triggered, having been frozen in _iresume()
// that preceded this point. So, the model is to trigger the
// registere to collect the numbers and record the start state
// that completes the 'resume' process.
perfctr_cpu_write_control(state);
{
struct perfctr_low_ctrs now;
unsigned int i, cstatus, nrctrs;
perfctr_cpu_read_counters(state, &now);
cstatus = state->cstatus;
// the start state of the registers has to be recorded only
// in resume() and that is what is being done.
if (perfctr_cstatus_has_tsc(cstatus)) {
state->tsc_start = now.tsc;
}
nrctrs = perfctr_cstatus_nractrs(cstatus);
for (i = 0; i < nrctrs; ++i) {
state->pmc[i].start = now.pmc[i];
}
}
/* XXX: if (SMP && start.tsc == now.tsc) ++now.tsc; */
}
static void mips_write_control(const struct perfctr_cpu_state *state)
{
struct per_cpu_cache *cache;
unsigned int nrctrs, i;
// cache stores the information pertaining to one id. Under
// what conditions does that cache state remain intact? Can some
// processes tell that their statistics be not recorded. In such
// a case when a thread is rescheuldes on the same processpor
// without the intervening thread recording the statistics, then
// the cache will be hot
cache = get_cpu_cache();
if (cache->k1.id == state->k1.id) {
return;
}
nrctrs = perfctr_cstatus_nrctrs(state->cstatus);
preempt_disable();
for (i = 0; i < nrctrs; ++i) {
unsigned int ctrl_reg = state->control.pmc[i].ctrl_reg;
unsigned int pmc = state->pmc[i].map; // assuming that the 'state' values have been
// updated from control values specified by users
if (ctrl_reg != cache->ctrl_regs[pmc]) {
if (!perfctr_cntmode) {
MIPS_XLR_UNSET_CNT_ALL_THREADS(ctrl_reg);
MIPS_XLR_SET_THREADID(ctrl_reg, netlogic_thr_id());
}
else {
MIPS_XLR_SET_CNT_ALL_THREADS(ctrl_reg);
}
cache->ctrl_regs[pmc] = ctrl_reg;
write_pmctrl(pmc, ctrl_reg);
}
}
cache->k1.id = state->k1.id;
preempt_enable();
}