powerpc/perf: Trace imc PMU functions

Add PMU functions to support trace-imc.

Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Anju T Sudhakar 2019-04-16 15:18:31 +05:30 committed by Michael Ellerman
parent 72c69dcddc
commit 012ae24484

View File

@ -53,7 +53,7 @@ static struct imc_pmu *imc_event_to_pmu(struct perf_event *event)
return container_of(event->pmu, struct imc_pmu, pmu);
}
PMU_FORMAT_ATTR(event, "config:0-40");
PMU_FORMAT_ATTR(event, "config:0-61");
PMU_FORMAT_ATTR(offset, "config:0-31");
PMU_FORMAT_ATTR(rvalue, "config:32");
PMU_FORMAT_ATTR(mode, "config:33-40");
@ -70,6 +70,25 @@ static struct attribute_group imc_format_group = {
.attrs = imc_format_attrs,
};
/* Format attribute for imc trace-mode */
PMU_FORMAT_ATTR(cpmc_reserved, "config:0-19");
PMU_FORMAT_ATTR(cpmc_event, "config:20-27");
PMU_FORMAT_ATTR(cpmc_samplesel, "config:28-29");
PMU_FORMAT_ATTR(cpmc_load, "config:30-61");
static struct attribute *trace_imc_format_attrs[] = {
&format_attr_event.attr,
&format_attr_cpmc_reserved.attr,
&format_attr_cpmc_event.attr,
&format_attr_cpmc_samplesel.attr,
&format_attr_cpmc_load.attr,
NULL,
};
static struct attribute_group trace_imc_format_group = {
.name = "format",
.attrs = trace_imc_format_attrs,
};
/* Get the cpumask printed to a buffer "buf" */
static ssize_t imc_pmu_cpumask_get_attr(struct device *dev,
struct device_attribute *attr,
@ -1113,6 +1132,182 @@ static int trace_imc_cpu_init(void)
ppc_trace_imc_cpu_offline);
}
static u64 get_trace_imc_event_base_addr(void)
{
return (u64)per_cpu(trace_imc_mem, smp_processor_id());
}
/*
* Function to parse trace-imc data obtained
* and to prepare the perf sample.
*/
static int trace_imc_prepare_sample(struct trace_imc_data *mem,
struct perf_sample_data *data,
u64 *prev_tb,
struct perf_event_header *header,
struct perf_event *event)
{
/* Sanity checks for a valid record */
if (be64_to_cpu(READ_ONCE(mem->tb1)) > *prev_tb)
*prev_tb = be64_to_cpu(READ_ONCE(mem->tb1));
else
return -EINVAL;
if ((be64_to_cpu(READ_ONCE(mem->tb1)) & IMC_TRACE_RECORD_TB1_MASK) !=
be64_to_cpu(READ_ONCE(mem->tb2)))
return -EINVAL;
/* Prepare perf sample */
data->ip = be64_to_cpu(READ_ONCE(mem->ip));
data->period = event->hw.last_period;
header->type = PERF_RECORD_SAMPLE;
header->size = sizeof(*header) + event->header_size;
header->misc = 0;
if (is_kernel_addr(data->ip))
header->misc |= PERF_RECORD_MISC_KERNEL;
else
header->misc |= PERF_RECORD_MISC_USER;
perf_event_header__init_id(header, data, event);
return 0;
}
static void dump_trace_imc_data(struct perf_event *event)
{
struct trace_imc_data *mem;
int i, ret;
u64 prev_tb = 0;
mem = (struct trace_imc_data *)get_trace_imc_event_base_addr();
for (i = 0; i < (trace_imc_mem_size / sizeof(struct trace_imc_data));
i++, mem++) {
struct perf_sample_data data;
struct perf_event_header header;
ret = trace_imc_prepare_sample(mem, &data, &prev_tb, &header, event);
if (ret) /* Exit, if not a valid record */
break;
else {
/* If this is a valid record, create the sample */
struct perf_output_handle handle;
if (perf_output_begin(&handle, event, header.size))
return;
perf_output_sample(&handle, &header, &data, event);
perf_output_end(&handle);
}
}
}
static int trace_imc_event_add(struct perf_event *event, int flags)
{
int core_id = smp_processor_id() / threads_per_core;
struct imc_pmu_ref *ref = NULL;
u64 local_mem, ldbar_value;
/* Set trace-imc bit in ldbar and load ldbar with per-thread memory address */
local_mem = get_trace_imc_event_base_addr();
ldbar_value = ((u64)local_mem & THREAD_IMC_LDBAR_MASK) | TRACE_IMC_ENABLE;
if (core_imc_refc)
ref = &core_imc_refc[core_id];
if (!ref) {
/* If core-imc is not enabled, use trace-imc reference count */
if (trace_imc_refc)
ref = &trace_imc_refc[core_id];
if (!ref)
return -EINVAL;
}
mtspr(SPRN_LDBAR, ldbar_value);
mutex_lock(&ref->lock);
if (ref->refc == 0) {
if (opal_imc_counters_start(OPAL_IMC_COUNTERS_TRACE,
get_hard_smp_processor_id(smp_processor_id()))) {
mutex_unlock(&ref->lock);
pr_err("trace-imc: Unable to start the counters for core %d\n", core_id);
mtspr(SPRN_LDBAR, 0);
return -EINVAL;
}
}
++ref->refc;
mutex_unlock(&ref->lock);
return 0;
}
static void trace_imc_event_read(struct perf_event *event)
{
return;
}
static void trace_imc_event_stop(struct perf_event *event, int flags)
{
u64 local_mem = get_trace_imc_event_base_addr();
dump_trace_imc_data(event);
memset((void *)local_mem, 0, sizeof(u64));
}
static void trace_imc_event_start(struct perf_event *event, int flags)
{
return;
}
static void trace_imc_event_del(struct perf_event *event, int flags)
{
int core_id = smp_processor_id() / threads_per_core;
struct imc_pmu_ref *ref = NULL;
if (core_imc_refc)
ref = &core_imc_refc[core_id];
if (!ref) {
/* If core-imc is not enabled, use trace-imc reference count */
if (trace_imc_refc)
ref = &trace_imc_refc[core_id];
if (!ref)
return;
}
mtspr(SPRN_LDBAR, 0);
mutex_lock(&ref->lock);
ref->refc--;
if (ref->refc == 0) {
if (opal_imc_counters_stop(OPAL_IMC_COUNTERS_TRACE,
get_hard_smp_processor_id(smp_processor_id()))) {
mutex_unlock(&ref->lock);
pr_err("trace-imc: Unable to stop the counters for core %d\n", core_id);
return;
}
} else if (ref->refc < 0) {
ref->refc = 0;
}
mutex_unlock(&ref->lock);
trace_imc_event_stop(event, flags);
}
static int trace_imc_event_init(struct perf_event *event)
{
struct task_struct *target;
if (event->attr.type != event->pmu->type)
return -ENOENT;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
/* Return if this is a couting event */
if (event->attr.sample_period == 0)
return -ENOENT;
event->hw.idx = -1;
target = event->hw.target;
event->pmu->task_ctx_nr = perf_hw_context;
return 0;
}
/* update_pmu_ops : Populate the appropriate operations for "pmu" */
static int update_pmu_ops(struct imc_pmu *pmu)
{
@ -1143,6 +1338,14 @@ static int update_pmu_ops(struct imc_pmu *pmu)
pmu->pmu.cancel_txn = thread_imc_pmu_cancel_txn;
pmu->pmu.commit_txn = thread_imc_pmu_commit_txn;
break;
case IMC_DOMAIN_TRACE:
pmu->pmu.event_init = trace_imc_event_init;
pmu->pmu.add = trace_imc_event_add;
pmu->pmu.del = trace_imc_event_del;
pmu->pmu.start = trace_imc_event_start;
pmu->pmu.stop = trace_imc_event_stop;
pmu->pmu.read = trace_imc_event_read;
pmu->attr_groups[IMC_FORMAT_ATTR] = &trace_imc_format_group;
default:
break;
}