[PATCH v3 08/10] coresight: trbe: Unify the enabling sequence

Suzuki K Poulose suzuki.poulose at arm.com
Tue Sep 14 03:26:39 PDT 2021


Unify the sequence of enabling the TRBE. We do this from
event_start and also from the TRBE IRQ handler. Lets move
this to a common helper. The only minor functional change
is returning an error when we fail to enable the TRBE.
This should be handled already.

Since we now have unique entry point to trying to enable TRBE,
move the format flag setting to the central place.

Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
Cc: Mike Leach <mike.leach at linaro.org>
Cc: Leo Yan <leo.yan at linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual at arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
---
Changes since v2:
 - Removed redundant handle book keeping (Anshuman)
 - Moved the format flag setting to the helper
---
 drivers/hwtracing/coresight/coresight-trbe.c | 37 ++++++++++----------
 1 file changed, 18 insertions(+), 19 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index a1a15fa6c4ae..25c16d0f9e49 100644
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -629,6 +629,21 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev,
 	return size;
 }
 
+static int __arm_trbe_enable(struct trbe_buf *buf,
+			     struct perf_output_handle *handle)
+{
+	perf_aux_output_flag(handle, PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
+	buf->trbe_limit = compute_trbe_buffer_limit(handle);
+	buf->trbe_write = buf->trbe_base + PERF_IDX2OFF(handle->head, buf);
+	if (buf->trbe_limit == buf->trbe_base) {
+		trbe_stop_and_truncate_event(handle);
+		return -ENOSPC;
+	}
+	*this_cpu_ptr(buf->cpudata->drvdata->handle) = handle;
+	trbe_enable_hw(buf);
+	return 0;
+}
+
 static int arm_trbe_enable(struct coresight_device *csdev, u32 mode, void *data)
 {
 	struct trbe_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -641,19 +656,11 @@ static int arm_trbe_enable(struct coresight_device *csdev, u32 mode, void *data)
 	if (mode != CS_MODE_PERF)
 		return -EINVAL;
 
-	perf_aux_output_flag(handle, PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
-	*this_cpu_ptr(drvdata->handle) = handle;
 	cpudata->buf = buf;
 	cpudata->mode = mode;
 	buf->cpudata = cpudata;
-	buf->trbe_limit = compute_trbe_buffer_limit(handle);
-	buf->trbe_write = buf->trbe_base + PERF_IDX2OFF(handle->head, buf);
-	if (buf->trbe_limit == buf->trbe_base) {
-		trbe_stop_and_truncate_event(handle);
-		return 0;
-	}
-	trbe_enable_hw(buf);
-	return 0;
+
+	return __arm_trbe_enable(buf, handle);
 }
 
 static int arm_trbe_disable(struct coresight_device *csdev)
@@ -719,15 +726,7 @@ static void trbe_handle_overflow(struct perf_output_handle *handle)
 		*this_cpu_ptr(buf->cpudata->drvdata->handle) = NULL;
 		return;
 	}
-	perf_aux_output_flag(handle, PERF_AUX_FLAG_CORESIGHT_FORMAT_RAW);
-	buf->trbe_limit = compute_trbe_buffer_limit(handle);
-	buf->trbe_write = buf->trbe_base + PERF_IDX2OFF(handle->head, buf);
-	if (buf->trbe_limit == buf->trbe_base) {
-		trbe_stop_and_truncate_event(handle);
-		return;
-	}
-	*this_cpu_ptr(buf->cpudata->drvdata->handle) = handle;
-	trbe_enable_hw(buf);
+	__arm_trbe_enable(buf, handle);
 }
 
 static bool is_perf_trbe(struct perf_output_handle *handle)
-- 
2.24.1




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