Commit 41c0e5b7 authored by Suzuki K Poulose's avatar Suzuki K Poulose Committed by Mathieu Poirier
Browse files

coresight: trbe: Add a helper to calculate the trace generated 



We collect the trace from the TRBE on FILL event from IRQ context
and via update_buffer(), when the event is stopped. Let us
consolidate how we calculate the trace generated into a helper.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: default avatarAnshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-6-suzuki.poulose@arm.com


Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
parent a08025b3

drivers/hwtracing/coresight/coresight-trbe.c

+29 −18
Original line number Diff line number Diff line
@@ -499,6 +499,29 @@ static enum trbe_fault_action trbe_get_fault_act(u64 trbsr) 
	return TRBE_FAULT_ACT_SPURIOUS;

}



static unsigned long trbe_get_trace_size(struct perf_output_handle *handle,

					 struct trbe_buf *buf, bool wrap)

{

	u64 write;

	u64 start_off, end_off;



	/*

	 * If the TRBE has wrapped around the write pointer has

	 * wrapped and should be treated as limit.

	 */

	if (wrap)

		write = get_trbe_limit_pointer();

	else

		write = get_trbe_write_pointer();



	end_off = write - get_trbe_base_pointer();

	start_off = PERF_IDX2OFF(handle->head, buf);



	if (WARN_ON_ONCE(end_off < start_off))

		return 0;

	return (end_off - start_off);

}



static void *arm_trbe_alloc_buffer(struct coresight_device *csdev,

				   struct perf_event *event, void **pages,

				   int nr_pages, bool snapshot)
@@ -560,9 +583,9 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, 
	struct trbe_cpudata *cpudata = dev_get_drvdata(&csdev->dev);

	struct trbe_buf *buf = config;

	enum trbe_fault_action act;

	unsigned long size, offset;

	unsigned long write, base, status;

	unsigned long size, status;

	unsigned long flags;

	bool wrap = false;



	WARN_ON(buf->cpudata != cpudata);

	WARN_ON(cpudata->cpu != smp_processor_id());
@@ -602,8 +625,6 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, 
	 * handle gets freed in etm_event_stop().

	 */

	trbe_drain_and_disable_local();

	write = get_trbe_write_pointer();

	base = get_trbe_base_pointer();



	/* Check if there is a pending interrupt and handle it here */

	status = read_sysreg_s(SYS_TRBSR_EL1);
@@ -627,20 +648,11 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, 
			goto done;

		}



		/*

		 * Otherwise, the buffer is full and the write pointer

		 * has reached base. Adjust this back to the Limit pointer

		 * for correct size. Also, mark the buffer truncated.

		 */

		write = get_trbe_limit_pointer();

		trbe_report_wrap_event(handle);

		wrap = true;

	}



	offset = write - base;

	if (WARN_ON_ONCE(offset < PERF_IDX2OFF(handle->head, buf)))

		size = 0;

	else

		size = offset - PERF_IDX2OFF(handle->head, buf);

	size = trbe_get_trace_size(handle, buf, wrap);



done:

	local_irq_restore(flags);
@@ -721,11 +733,10 @@ static int trbe_handle_overflow(struct perf_output_handle *handle) 
{

	struct perf_event *event = handle->event;

	struct trbe_buf *buf = etm_perf_sink_config(handle);

	unsigned long offset, size;

	unsigned long size;

	struct etm_event_data *event_data;



	offset = get_trbe_limit_pointer() - get_trbe_base_pointer();

	size = offset - PERF_IDX2OFF(handle->head, buf);

	size = trbe_get_trace_size(handle, buf, true);

	if (buf->snapshot)

		handle->head += size;