[tip:perf/core] perf record: Implement COMPRESSED event record and its attributes

From: tip-bot for Alexey Budankov
Date: Sat May 18 2019 - 05:22:49 EST


Commit-ID: 42e1fd80a5b8bf9188ddb502b788433ece189aae
Gitweb: https://git.kernel.org/tip/42e1fd80a5b8bf9188ddb502b788433ece189aae
Author: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
AuthorDate: Mon, 18 Mar 2019 20:41:33 +0300
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 15 May 2019 16:36:49 -0300

perf record: Implement COMPRESSED event record and its attributes

Implemented PERF_RECORD_COMPRESSED event, related data types, header
feature and functions to write, read and print feature attributes from
the trace header section.

comp_mmap_len preserves the size of mmaped kernel buffer that was used
during collection. comp_mmap_len size is used on loading stage as the
size of decomp buffer for decompression of COMPRESSED events content.

Committer notes:

Fixed up conflict with BPF_PROG_INFO and BTF_BTF header features.

Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
Reviewed-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/ebbaf031-8dda-3864-ebc6-7922d43ee515@xxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/Documentation/perf.data-file-format.txt | 24 ++++++++++
tools/perf/builtin-record.c | 8 ++++
tools/perf/perf.h | 1 +
tools/perf/util/env.h | 10 ++++
tools/perf/util/event.c | 1 +
tools/perf/util/event.h | 7 +++
tools/perf/util/header.c | 53 ++++++++++++++++++++++
tools/perf/util/header.h | 1 +
8 files changed, 105 insertions(+)

diff --git a/tools/perf/Documentation/perf.data-file-format.txt b/tools/perf/Documentation/perf.data-file-format.txt
index 593ef49b273c..6967e9b02be5 100644
--- a/tools/perf/Documentation/perf.data-file-format.txt
+++ b/tools/perf/Documentation/perf.data-file-format.txt
@@ -272,6 +272,19 @@ struct {

Two uint64_t for the time of first sample and the time of last sample.

+ HEADER_COMPRESSED = 27,
+
+struct {
+ u32 version;
+ u32 type;
+ u32 level;
+ u32 ratio;
+ u32 mmap_len;
+};
+
+Indicates that trace contains records of PERF_RECORD_COMPRESSED type
+that have perf_events records in compressed form.
+
other bits are reserved and should ignored for now
HEADER_FEAT_BITS = 256,

@@ -437,6 +450,17 @@ struct auxtrace_error_event {
Describes a header feature. These are records used in pipe-mode that
contain information that otherwise would be in perf.data file's header.

+ PERF_RECORD_COMPRESSED = 81,
+
+struct compressed_event {
+ struct perf_event_header header;
+ char data[];
+};
+
+The header is followed by compressed data frame that can be decompressed
+into array of perf trace records. The size of the entire compressed event
+record including the header is limited by the max value of header.size.
+
Event types

Define the event attributes with their IDs.
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 386e665a166f..45a80b3584ad 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -372,6 +372,11 @@ static int record__mmap_flush_parse(const struct option *opt,
return 0;
}

+static int record__comp_enabled(struct record *rec)
+{
+ return rec->opts.comp_level > 0;
+}
+
static int process_synthesized_event(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
@@ -888,6 +893,8 @@ static void record__init_features(struct record *rec)
perf_header__clear_feat(&session->header, HEADER_CLOCKID);

perf_header__clear_feat(&session->header, HEADER_DIR_FORMAT);
+ if (!record__comp_enabled(rec))
+ perf_header__clear_feat(&session->header, HEADER_COMPRESSED);

perf_header__clear_feat(&session->header, HEADER_STAT);
}
@@ -1245,6 +1252,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
err = -1;
goto out_child;
}
+ session->header.env.comp_mmap_len = session->evlist->mmap_len;

err = bpf__apply_obj_config();
if (err) {
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index 369eae61068d..d59dee61b64d 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -86,6 +86,7 @@ struct record_opts {
int nr_cblocks;
int affinity;
int mmap_flush;
+ unsigned int comp_level;
};

enum perf_affinity {
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index 34868ca7efd1..271a90b326c4 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -63,6 +63,10 @@ struct perf_env {
struct cpu_cache_level *caches;
int caches_cnt;
u32 comp_ratio;
+ u32 comp_ver;
+ u32 comp_type;
+ u32 comp_level;
+ u32 comp_mmap_len;
struct numa_node *numa_nodes;
struct memory_node *memory_nodes;
unsigned long long memory_bsize;
@@ -81,6 +85,12 @@ struct perf_env {
} bpf_progs;
};

+enum perf_compress_type {
+ PERF_COMP_NONE = 0,
+ PERF_COMP_ZSTD,
+ PERF_COMP_MAX
+};
+
struct bpf_prog_info_node;
struct btf_node;

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index ba7be74fad6e..d1ad6c419724 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -68,6 +68,7 @@ static const char *perf_event__names[] = {
[PERF_RECORD_EVENT_UPDATE] = "EVENT_UPDATE",
[PERF_RECORD_TIME_CONV] = "TIME_CONV",
[PERF_RECORD_HEADER_FEATURE] = "FEATURE",
+ [PERF_RECORD_COMPRESSED] = "COMPRESSED",
};

static const char *perf_ns__names[] = {
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 4e908ec1ef64..9e999550f247 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -255,6 +255,7 @@ enum perf_user_event_type { /* above any possible kernel type */
PERF_RECORD_EVENT_UPDATE = 78,
PERF_RECORD_TIME_CONV = 79,
PERF_RECORD_HEADER_FEATURE = 80,
+ PERF_RECORD_COMPRESSED = 81,
PERF_RECORD_HEADER_MAX
};

@@ -627,6 +628,11 @@ struct feature_event {
char data[];
};

+struct compressed_event {
+ struct perf_event_header header;
+ char data[];
+};
+
union perf_event {
struct perf_event_header header;
struct mmap_event mmap;
@@ -660,6 +666,7 @@ union perf_event {
struct feature_event feat;
struct ksymbol_event ksymbol_event;
struct bpf_event bpf_event;
+ struct compressed_event pack;
};

void perf_event__print_totals(void);
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 2d2af2ac2b1e..847ae51a524b 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1344,6 +1344,30 @@ out:
return ret;
}

+static int write_compressed(struct feat_fd *ff __maybe_unused,
+ struct perf_evlist *evlist __maybe_unused)
+{
+ int ret;
+
+ ret = do_write(ff, &(ff->ph->env.comp_ver), sizeof(ff->ph->env.comp_ver));
+ if (ret)
+ return ret;
+
+ ret = do_write(ff, &(ff->ph->env.comp_type), sizeof(ff->ph->env.comp_type));
+ if (ret)
+ return ret;
+
+ ret = do_write(ff, &(ff->ph->env.comp_level), sizeof(ff->ph->env.comp_level));
+ if (ret)
+ return ret;
+
+ ret = do_write(ff, &(ff->ph->env.comp_ratio), sizeof(ff->ph->env.comp_ratio));
+ if (ret)
+ return ret;
+
+ return do_write(ff, &(ff->ph->env.comp_mmap_len), sizeof(ff->ph->env.comp_mmap_len));
+}
+
static void print_hostname(struct feat_fd *ff, FILE *fp)
{
fprintf(fp, "# hostname : %s\n", ff->ph->env.hostname);
@@ -1688,6 +1712,13 @@ static void print_cache(struct feat_fd *ff, FILE *fp __maybe_unused)
}
}

+static void print_compressed(struct feat_fd *ff, FILE *fp)
+{
+ fprintf(fp, "# compressed : %s, level = %d, ratio = %d\n",
+ ff->ph->env.comp_type == PERF_COMP_ZSTD ? "Zstd" : "Unknown",
+ ff->ph->env.comp_level, ff->ph->env.comp_ratio);
+}
+
static void print_pmu_mappings(struct feat_fd *ff, FILE *fp)
{
const char *delimiter = "# pmu mappings: ";
@@ -2667,6 +2698,27 @@ out:
return err;
}

+static int process_compressed(struct feat_fd *ff,
+ void *data __maybe_unused)
+{
+ if (do_read_u32(ff, &(ff->ph->env.comp_ver)))
+ return -1;
+
+ if (do_read_u32(ff, &(ff->ph->env.comp_type)))
+ return -1;
+
+ if (do_read_u32(ff, &(ff->ph->env.comp_level)))
+ return -1;
+
+ if (do_read_u32(ff, &(ff->ph->env.comp_ratio)))
+ return -1;
+
+ if (do_read_u32(ff, &(ff->ph->env.comp_mmap_len)))
+ return -1;
+
+ return 0;
+}
+
struct feature_ops {
int (*write)(struct feat_fd *ff, struct perf_evlist *evlist);
void (*print)(struct feat_fd *ff, FILE *fp);
@@ -2730,6 +2782,7 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
FEAT_OPN(DIR_FORMAT, dir_format, false),
FEAT_OPR(BPF_PROG_INFO, bpf_prog_info, false),
FEAT_OPR(BPF_BTF, bpf_btf, false),
+ FEAT_OPR(COMPRESSED, compressed, false),
};

struct header_print_data {
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index 386da49e1bfa..5b3abe4172e2 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -42,6 +42,7 @@ enum {
HEADER_DIR_FORMAT,
HEADER_BPF_PROG_INFO,
HEADER_BPF_BTF,
+ HEADER_COMPRESSED,
HEADER_LAST_FEATURE,
HEADER_FEAT_BITS = 256,
};