[Intel-gfx] [PATCH] drm/i915/perf: Consider OA buffer boundary when zeroing out reports

[Umesh Nerlige Ramappa]

For reports that are not powers of 2, reports at the end of the OA
buffer may get split across the buffer boundary. When zeroing out such
reports, take the split into consideration.

Fixes: 09a36015d9a0 ("drm/i915/perf: Clear out entire reports after reading if not power of 2 size")
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
---
 drivers/gpu/drm/i915/i915_perf.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index b5491a382bfd..9a8e329c5b5e 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -867,8 +867,17 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream,
 			oa_report_id_clear(stream, report32);
 			oa_timestamp_clear(stream, report32);
 		} else {
+			u8 *oa_buf_end = stream->oa_buffer.vaddr +
+					 stream->oa_buffer.vma->size;
+			u32 part = (u32)((void *)oa_buf_end - (void *)report32);
+
 			/* Zero out the entire report */
-			memset(report32, 0, report_size);
+			if (report_size <= part) {
+				memset(report32, 0, report_size);
+			} else {
+				memset(report32, 0, part);
+				memset(oa_buf_base, 0, report_size - part);
+			}
 		}
 	}
 
-- 
2.36.1