[PATCH v2 4/4] perf report: support record trace file decompression
From: Alexey Budankov
Date: Mon Feb 11 2019 - 15:25:08 EST
PERF_RECORD_COMPRESSED records are decompressed from trace file into
a linked list of mmaped memory regions using streaming Zstandard API.
After that the regions are loaded fetching uncompressed events. When
dumping raw trace (e.g., perf report -D --header) file offsets of
events from compressed records are set to zero.
Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
---
Changes in v2:
- moved compression/decompression code to session layer
---
tools/perf/builtin-report.c | 5 +-
tools/perf/util/session.c | 165 +++++++++++++++++++++++++++++++++++-
tools/perf/util/session.h | 11 +++
tools/perf/util/tool.h | 2 +
4 files changed, 181 insertions(+), 2 deletions(-)
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 2e8c74d6430c..3bfb74c11875 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -1215,6 +1215,9 @@ int cmd_report(int argc, const char **argv)
if (session == NULL)
return -1;
+ if (perf_session__zstd_init(session, 0) < 0)
+ pr_warning("Decompression initialization failed. Reported data may be incomplete.\n");
+
if (report.queue_size) {
ordered_events__set_alloc_size(&session->ordered_events,
report.queue_size);
@@ -1427,7 +1430,7 @@ int cmd_report(int argc, const char **argv)
error:
zfree(&report.ptime_range);
-
+ perf_session__zstd_fini(session);
perf_session__delete(session);
return ret;
}
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 5d406eebd058..c501cb904d95 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -34,6 +34,21 @@ int perf_session__zstd_init(struct perf_session *session, int level)
{
size_t ret;
+ session->zstd_dstream = ZSTD_createDStream();
+ if (session->zstd_dstream == NULL) {
+ pr_err("Couldn't create decompression stream.\n");
+ return -1;
+ }
+
+ ret = ZSTD_initDStream(session->zstd_dstream);
+ if (ZSTD_isError(ret)) {
+ pr_err("Failed to initialize decompression stream: %s\n", ZSTD_getErrorName(ret));
+ return -1;
+ }
+
+ if (level == 0)
+ return 0;
+
session->header.env.comp_type = PERF_COMP_NONE;
session->header.env.comp_level = 0;
@@ -57,6 +72,22 @@ int perf_session__zstd_init(struct perf_session *session, int level)
int perf_session__zstd_fini(struct perf_session *session)
{
+ struct decomp *next = session->decomp, *decomp;
+ size_t decomp_len = session->header.env.comp_mmap_len;
+
+ if (session->zstd_dstream) {
+ ZSTD_freeDStream(session->zstd_dstream);
+ session->zstd_dstream = NULL;
+ }
+
+ do {
+ decomp = next;
+ if (decomp == NULL)
+ break;
+ next = decomp->next;
+ munmap(decomp, decomp_len + sizeof(struct decomp));
+ } while (1);
+
if (session->zstd_cstream) {
ZSTD_freeCStream(session->zstd_cstream);
session->zstd_cstream = NULL;
@@ -108,6 +139,80 @@ size_t perf_session__zstd_compress(void *to, void *dst, size_t dst_size,
return compressed;
}
+
+static size_t perf_session__zstd_decompress(struct perf_session *session,
+ 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(session->zstd_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;
+}
+
+static int perf_session__process_compressed_event(struct perf_session *session,
+ union perf_event *event, u64 file_offset)
+{
+ void *src;
+ size_t decomp_size, src_size;
+ u64 decomp_last_rem = 0;
+ size_t decomp_len = session->header.env.comp_mmap_len;
+ struct decomp *decomp, *decomp_last = session->decomp_last;
+
+ decomp = mmap(NULL, sizeof(struct decomp) + decomp_len, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ if (decomp == MAP_FAILED) {
+ pr_err("Couldn't allocate memory for decompression\n");
+ return -1;
+ }
+
+ decomp->file_pos = file_offset;
+ decomp->head = 0;
+
+ if (decomp_last) {
+ decomp_last_rem = decomp_last->size - decomp_last->head;
+ memcpy(decomp->data, &(decomp_last->data[decomp_last->head]), decomp_last_rem);
+ decomp->size = decomp_last_rem;
+ }
+
+ src = (void *)event + sizeof(struct compressed_event);
+ src_size = event->pack.header.size - sizeof(struct compressed_event);
+
+ decomp_size = perf_session__zstd_decompress(session, src, src_size,
+ &(decomp->data[decomp_last_rem]), decomp_len - decomp_last_rem);
+ if (!decomp_size) {
+ munmap(decomp, sizeof(struct decomp) + decomp_len);
+ pr_err("Couldn't decompress data\n");
+ return -1;
+ }
+
+ decomp->size += decomp_size;
+
+ if (session->decomp == NULL) {
+ session->decomp = decomp;
+ session->decomp_last = decomp;
+ } else {
+ session->decomp_last->next = decomp;
+ session->decomp_last = decomp;
+ }
+
+ pr_debug("decomp (B): %ld to %ld\n", src_size, decomp_size);
+
+ return 0;
+}
+
#else /* !HAVE_ZSTD_SUPPORT */
int perf_session__zstd_init(struct perf_session *session __maybe_unused, int level __maybe_unused)
{
@@ -125,6 +230,14 @@ size_t perf_session__zstd_compress(void *to __maybe_unused,
{
return 0;
}
+
+static int perf_session__process_compressed_event(struct perf_session *session __maybe_unused,
+ union perf_event *event __maybe_unused,
+ u64 file_offset __maybe_unused)
+{
+ dump_printf(": unhandled!\n");
+ return 0;
+}
#endif
size_t perf_session__zstd_copy(void *to __maybe_unused,
@@ -533,6 +646,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool)
tool->time_conv = process_event_op2_stub;
if (tool->feature == NULL)
tool->feature = process_event_op2_stub;
+ if (tool->compressed == NULL)
+ tool->compressed = perf_session__process_compressed_event;
}
static void swap_sample_id_all(union perf_event *event, void *data)
@@ -1469,7 +1584,8 @@ static s64 perf_session__process_user_event(struct perf_session *session,
int fd = perf_data__fd(session->data);
int err;
- dump_event(session->evlist, event, file_offset, &sample);
+ if (event->header.type != PERF_RECORD_COMPRESSED)
+ dump_event(session->evlist, event, file_offset, &sample);
/* These events are processed right away */
switch (event->header.type) {
@@ -1522,6 +1638,11 @@ static s64 perf_session__process_user_event(struct perf_session *session,
return tool->time_conv(session, event);
case PERF_RECORD_HEADER_FEATURE:
return tool->feature(session, event);
+ case PERF_RECORD_COMPRESSED:
+ err = tool->compressed(session, event, file_offset);
+ if (err)
+ dump_event(session->evlist, event, file_offset, &sample);
+ return 0;
default:
return -EINVAL;
}
@@ -1804,6 +1925,8 @@ static int perf_session__flush_thread_stacks(struct perf_session *session)
volatile int session_done;
+static int __perf_session__process_decomp_events(struct perf_session *session);
+
static int __perf_session__process_pipe_events(struct perf_session *session)
{
struct ordered_events *oe = &session->ordered_events;
@@ -1884,6 +2007,10 @@ static int __perf_session__process_pipe_events(struct perf_session *session)
if (skip > 0)
head += skip;
+ err = __perf_session__process_decomp_events(session);
+ if (err)
+ goto out_err;
+
if (!session_done())
goto more;
done:
@@ -1932,6 +2059,38 @@ fetch_mmaped_event(struct perf_session *session,
return event;
}
+static int __perf_session__process_decomp_events(struct perf_session *session)
+{
+ s64 skip;
+ u64 size, file_pos = 0;
+ union perf_event *event;
+ struct decomp *decomp = session->decomp_last;
+
+ if (!decomp)
+ return 0;
+
+ while (decomp->head < decomp->size && !session_done()) {
+ event = fetch_mmaped_event(session, decomp->head, decomp->size, decomp->data);
+ if (!event)
+ break;
+
+ size = event->header.size;
+ if (size < sizeof(struct perf_event_header) ||
+ (skip = perf_session__process_event(session, event, file_pos)) < 0) {
+ pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
+ decomp->file_pos + decomp->head, event->header.size, event->header.type);
+ return -EINVAL;
+ }
+
+ if (skip)
+ size += skip;
+
+ decomp->head += size;
+ }
+
+ return 0;
+}
+
/*
* On 64bit we can mmap the data file in one go. No need for tiny mmap
* slices. On 32bit we use 32MB.
@@ -2032,6 +2191,10 @@ reader__process_events(struct reader *rd, struct perf_session *session,
head += size;
file_pos += size;
+ err = __perf_session__process_decomp_events(session);
+ if (err)
+ goto out;
+
ui_progress__update(prog, size);
if (session_done())
diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index d8f3284cd838..06a0536adbe0 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -42,7 +42,18 @@ struct perf_session {
u64 bytes_compressed;
#ifdef HAVE_ZSTD_SUPPORT
ZSTD_CStream *zstd_cstream;
+ ZSTD_DStream *zstd_dstream;
#endif
+ struct decomp *decomp;
+ struct decomp *decomp_last;
+};
+
+struct decomp {
+ struct decomp *next;
+ u64 file_pos;
+ u64 head;
+ size_t size;
+ char data[];
};
struct perf_tool;
diff --git a/tools/perf/util/tool.h b/tools/perf/util/tool.h
index 250391672f9f..9096a6e3de59 100644
--- a/tools/perf/util/tool.h
+++ b/tools/perf/util/tool.h
@@ -28,6 +28,7 @@ typedef int (*event_attr_op)(struct perf_tool *tool,
typedef int (*event_op2)(struct perf_session *session, union perf_event *event);
typedef s64 (*event_op3)(struct perf_session *session, union perf_event *event);
+typedef int (*event_op4)(struct perf_session *session, union perf_event *event, u64 data);
typedef int (*event_oe)(struct perf_tool *tool, union perf_event *event,
struct ordered_events *oe);
@@ -72,6 +73,7 @@ struct perf_tool {
stat,
stat_round,
feature;
+ event_op4 compressed;
event_op3 auxtrace;
bool ordered_events;
bool ordering_requires_timestamps;