On 19/07/18 20:59, Mathieu Poirier wrote:
On Tue, Jul 17, 2018 at 06:11:41PM +0100, Suzuki K Poulose wrote:
Add support for using TMC-ETR as backend for ETM perf tracing. We use software double buffering at the moment. i.e, the TMC-ETR uses a separate buffer than the perf ring buffer. The data is copied to the perf ring buffer once a session completes.
The TMC-ETR would try to match the larger of perf ring buffer or the ETR buffer size configured via sysfs, scaling down to a minimum limit of 1MB.
Cc: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com
- CS_UNLOCK(drvdata->base);
- tmc_flush_and_stop(drvdata);
- tmc_sync_etr_buf(drvdata);
- CS_UNLOCK(drvdata->base);
This is a copy/paste oversight, here you want to lock again.
Thanks for catching that, will fix it.
- /* Reset perf specific data */
- drvdata->perf_data = NULL;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- size = etr_buf->len;
- tmc_etr_sync_perf_buffer(etr_perf);
- /*
* Update handle->head in snapshot mode. Also update the size to the* hardware buffer size if there was an overflow.*/- if (etr_perf->snapshot) {
handle->head += size;if (etr_buf->full)size = etr_buf->size;- }
- lost |= etr_buf->full;
+out:
- if (lost)
perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);- return size;
+}
- static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data) {
- /* We don't support perf mode yet ! */
- return -EINVAL;
- int rc = 0;
- unsigned long flags;
- struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
- struct perf_output_handle *handle = data;
- struct etr_perf_buffer *etr_perf = etm_perf_sink_config(handle);
- spin_lock_irqsave(&drvdata->spinlock, flags);
- /*
* There can be only one writer per sink in perf mode. If the sink* is already open in SYSFS mode, we can't use it.*/- if (drvdata->mode != CS_MODE_DISABLED || drvdata->perf_data) {
rc = -EBUSY;
As discussed in the previous patch, I am missing a WARN_ON here : i.e,
+ if (drvdata->mode != CS_MODE_DISABLED || WARN_ON(drvdata->perf_data))
which was there in the previous version in set_buffer, which triggered some warnings for me with testing.
goto unlock_out;- }
- if (WARN_ON(!etr_perf || !etr_perf->etr_buf)) {
rc = -EINVAL;goto unlock_out;- }
- etr_perf->head = PERF_IDX2OFF(handle->head, etr_perf);
- drvdata->perf_data = etr_perf;
- drvdata->mode = CS_MODE_PERF;
- tmc_etr_enable_hw(drvdata, etr_perf->etr_buf);
+unlock_out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return rc; }
static int tmc_enable_etr_sink(struct coresight_device *csdev, @@ -1148,6 +1389,9 @@ static void tmc_disable_etr_sink(struct coresight_device *csdev) static const struct coresight_ops_sink tmc_etr_sink_ops = { .enable = tmc_enable_etr_sink, .disable = tmc_disable_etr_sink,
- .alloc_buffer = tmc_etr_alloc_perf_buffer,
- .update_buffer = tmc_etr_update_perf_buffer,
- .free_buffer = tmc_etr_free_perf_buffer,
.alloc_buffer = tmc_alloc_etr_buffer, .update_buffer = tmc_update_etr_buffer, .free_buffer = tmc_free_etr_buffer,
To be consistant with .enable and .disable along with the naming convention on the ETF side.
Sure, I can change them.
Cheers Suzuki