coresight: trbe: Add a helper to pad a given buffer area

Refactor the helper to pad a given AUX buffer area to allow
"filling" ignore packets, without moving any handle pointers.
This will be useful in working around errata, where we may
have to fill the buffer after a session.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-7-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index 54f5d61ee9fb83f3cbe3b5e450aed4a1f7c1a0e6..e3767f21ee68df590ad0520c93f8b3092d61740a 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -199,12 +199,18 @@ static void trbe_stop_and_truncate_event(struct perf_output_handle *handle)
  * consumed from the user space. The enabled TRBE buffer area is a moving subset of
  * the allocated perf auxiliary buffer.
  */
+
+static void __trbe_pad_buf(struct trbe_buf *buf, u64 offset, int len)
+{
+       memset((void *)buf->trbe_base + offset, ETE_IGNORE_PACKET, len);
+}
+
 static void trbe_pad_buf(struct perf_output_handle *handle, int len)
 {
        struct trbe_buf *buf = etm_perf_sink_config(handle);
        u64 head = PERF_IDX2OFF(handle->head, buf);
 
-       memset((void *)buf->trbe_base + head, ETE_IGNORE_PACKET, len);
+       __trbe_pad_buf(buf, head, len);
        if (!buf->snapshot)
                perf_aux_output_skip(handle, len);
 }