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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /tools/perf/util/zstd.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'tools/perf/util/zstd.c')
-rw-r--r--tools/perf/util/zstd.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/tools/perf/util/zstd.c b/tools/perf/util/zstd.c
new file mode 100644
index 000000000..d98014902
--- /dev/null
+++ b/tools/perf/util/zstd.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <string.h>
+#include <linux/perf_event.h>
+
+#include "util/compress.h"
+#include "util/debug.h"
+
+int zstd_init(struct zstd_data *data, int level)
+{
+ data->comp_level = level;
+ data->dstream = NULL;
+ data->cstream = NULL;
+ return 0;
+}
+
+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;
+ }
+
+ return 0;
+}
+
+ssize_t zstd_compress_stream_to_records(struct zstd_data *data, void *dst, size_t dst_size,
+ void *src, size_t src_size, size_t max_record_size,
+ ssize_t process_header(void *record, size_t dst_size,
+ size_t data_size))
+{
+ size_t ret, compressed = 0;
+ ssize_t size;
+ ZSTD_inBuffer input = { src, src_size, 0 };
+ ZSTD_outBuffer output;
+ void *record;
+
+ if (!data->cstream) {
+ data->cstream = ZSTD_createCStream();
+ if (data->cstream == NULL) {
+ pr_err("Couldn't create compression stream.\n");
+ return -1;
+ }
+
+ ret = ZSTD_initCStream(data->cstream, data->comp_level);
+ if (ZSTD_isError(ret)) {
+ pr_err("Failed to initialize compression stream: %s\n",
+ ZSTD_getErrorName(ret));
+ return -1;
+ }
+ }
+
+ while (input.pos < input.size) {
+ record = dst;
+ size = process_header(record, dst_size, 0);
+ /* Output buffer full — cannot fit even the record header */
+ if (size < 0)
+ goto reset;
+ compressed += size;
+ dst += size;
+ dst_size -= size;
+ output = (ZSTD_outBuffer){ dst, (dst_size > max_record_size) ?
+ max_record_size : dst_size, 0 };
+ ret = ZSTD_compressStream(data->cstream, &output, &input);
+ ZSTD_flushStream(data->cstream, &output);
+ if (ZSTD_isError(ret)) {
+ pr_err("failed to compress %ld bytes: %s\n",
+ (long)src_size, ZSTD_getErrorName(ret));
+ goto reset;
+ }
+ compressed += output.pos;
+ dst += output.pos;
+ dst_size -= output.pos;
+ /*
+ * No progress: ZSTD couldn't emit any bytes into the
+ * remaining output buffer. Calling process_header
+ * with output.pos=0 would re-trigger header initialization,
+ * double-subtracting the header size from dst_size and
+ * underflowing the unsigned counter.
+ */
+ if (output.pos == 0)
+ goto reset;
+ size = process_header(record, dst_size, output.pos);
+ if (size < 0)
+ goto reset;
+ compressed += size;
+ dst += size;
+ dst_size -= size;
+ }
+
+ return compressed;
+
+reset:
+ /* Reset so the context is usable if the caller retries */
+ ret = ZSTD_initCStream(data->cstream, data->comp_level);
+ if (ZSTD_isError(ret))
+ pr_err("failed to reset compression context: %s\n",
+ ZSTD_getErrorName(ret));
+ return -1;
+}
+
+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 };
+
+ if (!data->dstream) {
+ data->dstream = ZSTD_createDStream();
+ if (data->dstream == NULL) {
+ pr_err("Couldn't create decompression stream.\n");
+ return 0;
+ }
+
+ ret = ZSTD_initDStream(data->dstream);
+ if (ZSTD_isError(ret)) {
+ pr_err("Failed to initialize decompression stream: %s\n",
+ ZSTD_getErrorName(ret));
+ return 0;
+ }
+ }
+ while (input.pos < input.size) {
+ size_t prev_in = input.pos;
+ size_t prev_out = output.pos;
+
+ ret = ZSTD_decompressStream(data->dstream, &output, &input);
+ if (ZSTD_isError(ret)) {
+ pr_err("failed to decompress (B): %zd -> %zd, dst_size %zd : %s\n",
+ src_size, output.pos, dst_size, ZSTD_getErrorName(ret));
+ return 0;
+ }
+ /*
+ * Neither stream advanced — decompression is stuck.
+ * Return 0 (error) rather than partial output: perf
+ * uses ZSTD_flushStream (not ZSTD_endStream), so the
+ * stream is continuous across compressed events.
+ * Discarding unconsumed input would desynchronize the
+ * decompressor, causing the next call to produce
+ * garbage that could be misinterpreted as valid events.
+ */
+ if (input.pos == prev_in && output.pos == prev_out)
+ return 0;
+ }
+
+ return output.pos;
+}