1 files changed, 41 insertions, 0 deletions

diff --git a/tools/perf/util/zstd.c b/tools/perf/util/zstd.c
index 359ec9a9d306..23bdb9884576 100644
--- a/tools/perf/util/zstd.c
+++ b/tools/perf/util/zstd.c
@@ -9,6 +9,21 @@ int zstd_init(struct zstd_data *data, int level)
 {
 	size_t ret;
 
+	data->dstream = ZSTD_createDStream();
+	if (data->dstream == NULL) {
+		pr_err("Couldn't create decompression stream.\n");
+		return -1;
+	}
+
+	ret = ZSTD_initDStream(data->dstream);
+	if (ZSTD_isError(ret)) {
+		pr_err("Failed to initialize decompression stream: %s\n", ZSTD_getErrorName(ret));
+		return -1;
+	}
+
+	if (!level)
+		return 0;
+
 	data->cstream = ZSTD_createCStream();
 	if (data->cstream == NULL) {
 		pr_err("Couldn't create compression stream.\n");
@@ -26,6 +41,11 @@ int zstd_init(struct zstd_data *data, int level)
 
 int zstd_fini(struct zstd_data *data)
 {
+	if (data->dstream) {
+		ZSTD_freeDStream(data->dstream);
+		data->dstream = NULL;
+	}
+
 	if (data->cstream) {
 		ZSTD_freeCStream(data->cstream);
 		data->cstream = NULL;
@@ -68,3 +88,24 @@ size_t zstd_compress_stream_to_records(struct zstd_data *data, void *dst, size_t
 
 	return compressed;
 }
+
+size_t zstd_decompress_stream(struct zstd_data *data, void *src, size_t src_size,
+			      void *dst, size_t dst_size)
+{
+	size_t ret;
+	ZSTD_inBuffer input = { src, src_size, 0 };
+	ZSTD_outBuffer output = { dst, dst_size, 0 };
+
+	while (input.pos < input.size) {
+		ret = ZSTD_decompressStream(data->dstream, &output, &input);
+		if (ZSTD_isError(ret)) {
+			pr_err("failed to decompress (B): %ld -> %ld : %s\n",
+			       src_size, output.size, ZSTD_getErrorName(ret));
+			break;
+		}
+		output.dst  = dst + output.pos;
+		output.size = dst_size - output.pos;
+	}
+
+	return output.pos;
+}