[PATCH v1 2/4] perf record: introduce z, mmap-flush options and PERF_RECORD_COMPRESSED record

From: Alexey Budankov
Date: Mon Dec 24 2018 - 08:46:42 EST



Introduce --compression_level=n, --mmap-flush options and PERF_RECORD_COMPRESSED
event record that contains compressed parts of mmap kernel buffer data.

Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
---
tools/perf/Documentation/perf-record.txt | 11 +++
tools/perf/builtin-record.c | 97 ++++++++++++++++++++----
tools/perf/perf.h | 2 +
tools/perf/util/env.h | 10 +++
tools/perf/util/event.c | 1 +
tools/perf/util/event.h | 7 ++
tools/perf/util/evlist.c | 6 +-
tools/perf/util/evlist.h | 2 +-
tools/perf/util/header.c | 47 +++++++++++-
tools/perf/util/header.h | 1 +
tools/perf/util/mmap.c | 4 +-
tools/perf/util/mmap.h | 3 +-
12 files changed, 169 insertions(+), 22 deletions(-)

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index d232b13ea713..b849dfdefefe 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -440,6 +440,17 @@ Use <n> control blocks in asynchronous (Posix AIO) trace writing mode (default:
Asynchronous mode is supported only when linking Perf tool with libc library
providing implementation for Posix AIO API.

+-z::
+--compression-level=n::
+Produce compressed trace file to save storage space using specified level n (default: 0,
+best speed: 1, best compression: 22). Compression can be activated in asynchronous trace
+writing mode (--aio) only.
+
+--mmap-flush=n::
+Minimal number of bytes accumulated in mmap buffer that is flushed to trace file (default: 1).
+When compression mode (-z) is enabled it is recommended to set --mmap-flush to 4096 or more.
+Maximal allowed value is a quater of mmap kernel buffer size.
+
--all-kernel::
Configure all used events to run in kernel space.

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 882285fb9f64..cb0b880281d7 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -81,6 +81,8 @@ struct record {
bool timestamp_boundary;
struct switch_output switch_output;
unsigned long long samples;
+ u64 bytes_transferred;
+ u64 bytes_compressed;
};

static volatile int auxtrace_record__snapshot_started;
@@ -286,13 +288,17 @@ static int record__aio_parse(const struct option *opt,

if (unset) {
opts->nr_cblocks = 0;
- } else {
- if (str)
- opts->nr_cblocks = strtol(str, NULL, 0);
- if (!opts->nr_cblocks)
- opts->nr_cblocks = nr_cblocks_default;
+ return 0;
}

+ if (str)
+ opts->nr_cblocks = strtol(str, NULL, 0);
+ if (!opts->nr_cblocks)
+ opts->nr_cblocks = nr_cblocks_default;
+
+ if (opts->nr_cblocks > nr_cblocks_max)
+ opts->nr_cblocks = nr_cblocks_max;
+
return 0;
}
#else /* HAVE_AIO_SUPPORT */
@@ -328,6 +334,30 @@ static int record__aio_enabled(struct record *rec)
return rec->opts.nr_cblocks > 0;
}

+#define MMAP_FLUSH_DEFAULT 1
+
+static int record__mmap_flush_parse(const struct option *opt,
+ const char *str,
+ int unset)
+{
+ int mmap_len;
+ struct record_opts *opts = (struct record_opts *)opt->value;
+
+ if (unset)
+ return 0;
+
+ if (str)
+ opts->mmap_flush = strtol(str, NULL, 0);
+ if (!opts->mmap_flush)
+ opts->mmap_flush = MMAP_FLUSH_DEFAULT;
+
+ mmap_len = perf_evlist__mmap_size(opts->mmap_pages);
+ if (opts->mmap_flush > mmap_len / 4 )
+ opts->mmap_flush = mmap_len / 4;
+
+ return 0;
+}
+
static int process_synthesized_event(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
@@ -533,7 +563,8 @@ static int record__mmap_evlist(struct record *rec,

if (perf_evlist__mmap_ex(evlist, opts->mmap_pages,
opts->auxtrace_mmap_pages,
- opts->auxtrace_snapshot_mode, opts->nr_cblocks) < 0) {
+ opts->auxtrace_snapshot_mode,
+ opts->nr_cblocks, opts->mmap_flush) < 0) {
if (errno == EPERM) {
pr_err("Permission error mapping pages.\n"
"Consider increasing "
@@ -723,7 +754,7 @@ static struct perf_event_header finished_round_event = {
};

static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evlist,
- bool overwrite)
+ bool overwrite, bool sync)
{
u64 bytes_written = rec->bytes_written;
int i;
@@ -746,11 +777,18 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
off = record__aio_get_pos(trace_fd);

for (i = 0; i < evlist->nr_mmaps; i++) {
+ u64 flush;
struct perf_mmap *map = &maps[i];

if (map->base) {
+ if (sync) {
+ flush = map->flush;
+ map->flush = MMAP_FLUSH_DEFAULT;
+ }
if (!record__aio_enabled(rec)) {
if (perf_mmap__push(map, rec, record__pushfn) != 0) {
+ if (sync)
+ map->flush = flush;
rc = -1;
goto out;
}
@@ -763,10 +801,14 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
idx = record__aio_sync(map, false);
if (perf_mmap__aio_push(map, rec, idx, record__aio_pushfn, &off) != 0) {
record__aio_set_pos(trace_fd, off);
+ if (sync)
+ map->flush = flush;
rc = -1;
goto out;
}
}
+ if (sync)
+ map->flush = flush;
}

if (map->auxtrace_mmap.base && !rec->opts.auxtrace_snapshot_mode &&
@@ -792,15 +834,15 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
return rc;
}

-static int record__mmap_read_all(struct record *rec)
+static int record__mmap_read_all(struct record *rec, bool sync)
{
int err;

- err = record__mmap_read_evlist(rec, rec->evlist, false);
+ err = record__mmap_read_evlist(rec, rec->evlist, false, sync);
if (err)
return err;

- return record__mmap_read_evlist(rec, rec->evlist, true);
+ return record__mmap_read_evlist(rec, rec->evlist, true, sync);
}

static void record__init_features(struct record *rec)
@@ -826,6 +868,9 @@ static void record__init_features(struct record *rec)
if (!(rec->opts.use_clockid && rec->opts.clockid_res_ns))
perf_header__clear_feat(&session->header, HEADER_CLOCKID);

+ if (!(rec->opts.comp_level && rec->opts.nr_cblocks))
+ perf_header__clear_feat(&session->header, HEADER_COMPRESSED);
+
perf_header__clear_feat(&session->header, HEADER_STAT);
}

@@ -1130,6 +1175,10 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
fd = perf_data__fd(data);
rec->session = session;

+ session->header.env.comp_type = PERF_COMP_NONE;
+ rec->opts.comp_level = 0;
+ session->header.env.comp_level = rec->opts.comp_level;
+
record__init_features(rec);

if (rec->opts.use_clockid && rec->opts.clockid_res_ns)
@@ -1159,6 +1208,7 @@ 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) {
@@ -1294,7 +1344,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
if (trigger_is_hit(&switch_output_trigger) || done || draining)
perf_evlist__toggle_bkw_mmap(rec->evlist, BKW_MMAP_DATA_PENDING);

- if (record__mmap_read_all(rec) < 0) {
+ if (record__mmap_read_all(rec, false) < 0) {
trigger_error(&auxtrace_snapshot_trigger);
trigger_error(&switch_output_trigger);
err = -1;
@@ -1395,8 +1445,16 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
record__synthesize_workload(rec, true);

out_child:
+ record__mmap_read_all(rec, true);
record__aio_mmap_read_sync(rec);

+ if (!quiet && rec->bytes_transferred && rec->bytes_compressed) {
+ float ratio = (float)rec->bytes_transferred/(float)rec->bytes_compressed;
+ session->header.env.comp_ratio = ratio + 0.5;
+ fprintf(stderr, "[ perf record: Compressed %.3f MB to %.3f MB, ratio is %.3f ]\n",
+ rec->bytes_transferred / 1024.0 / 1024.0, rec->bytes_compressed / 1024.0 / 1024.0, ratio);
+ }
+
if (forks) {
int exit_status;

@@ -1782,6 +1840,7 @@ static struct record record = {
.uses_mmap = true,
.default_per_cpu = true,
},
+ .mmap_flush = MMAP_FLUSH_DEFAULT,
},
.tool = {
.sample = process_sample_event,
@@ -1945,7 +2004,12 @@ static struct option __record_options[] = {
OPT_CALLBACK_OPTARG(0, "aio", &record.opts,
&nr_cblocks_default, "n", "Use <n> control blocks in asynchronous trace writing mode (default: 1, max: 4)",
record__aio_parse),
+ OPT_UINTEGER('z', "compression-level", &record.opts.comp_level,
+ "Produce compressed trace file (default: 0, best speed: 1, best compression: 22)"),
#endif
+ OPT_CALLBACK(0, "mmap-flush", &record.opts, "num",
+ "Minimal number of bytes in mmap buffer that is flushed to trace file (default: 1)",
+ record__mmap_flush_parse),
OPT_END()
};

@@ -2138,10 +2202,13 @@ int cmd_record(int argc, const char **argv)
goto out;
}

- if (rec->opts.nr_cblocks > nr_cblocks_max)
- rec->opts.nr_cblocks = nr_cblocks_max;
- if (verbose > 0)
- pr_info("nr_cblocks: %d\n", rec->opts.nr_cblocks);
+ pr_debug("nr_cblocks: %d\n", rec->opts.nr_cblocks);
+
+ if (rec->opts.comp_level > 22)
+ rec->opts.comp_level = 0;
+ pr_debug("Compression level: %d\n", rec->opts.comp_level);
+
+ pr_debug("mmap flush (B): %d\n", rec->opts.mmap_flush);

err = __cmd_record(&record, argc, argv);
out:
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index 388c6dd128b8..0352b5a5b9d5 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -83,6 +83,8 @@ struct record_opts {
clockid_t clockid;
u64 clockid_res_ns;
int nr_cblocks;
+ unsigned int comp_level;
+ int mmap_flush;
};

struct option;
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index d01b8355f4ca..3d1ab2ccc128 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -64,6 +64,16 @@ struct perf_env {
struct memory_node *memory_nodes;
unsigned long long memory_bsize;
u64 clockid_res_ns;
+ u32 comp_type;
+ u32 comp_level;
+ u32 comp_ratio;
+ u32 comp_mmap_len;
+};
+
+enum perf_compress_type {
+ PERF_COMP_NONE = 0,
+ PERF_COMP_ZSTD,
+ PERF_COMP_EOF
};

extern struct perf_env perf_env;
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 937a5a4f71cc..20730ba2a08b 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -62,6 +62,7 @@ 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 eb95f3384958..03960cfbe8d3 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -249,6 +249,7 @@ 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
};

@@ -620,6 +621,11 @@ 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;
@@ -651,6 +657,7 @@ union perf_event {
struct stat_round_event stat_round;
struct time_conv_event time_conv;
struct feature_event feat;
+ struct compressed_event pack;
};

void perf_event__print_totals(void);
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 8c902276d4b4..c82d4fd32dcf 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1022,7 +1022,7 @@ int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
*/
int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,
unsigned int auxtrace_pages,
- bool auxtrace_overwrite, int nr_cblocks)
+ bool auxtrace_overwrite, int nr_cblocks, int flush)
{
struct perf_evsel *evsel;
const struct cpu_map *cpus = evlist->cpus;
@@ -1032,7 +1032,7 @@ int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,
* Its value is decided by evsel's write_backward.
* So &mp should not be passed through const pointer.
*/
- struct mmap_params mp = { .nr_cblocks = nr_cblocks };
+ struct mmap_params mp = { .nr_cblocks = nr_cblocks, .flush = flush };

if (!evlist->mmap)
evlist->mmap = perf_evlist__alloc_mmap(evlist, false);
@@ -1064,7 +1064,7 @@ int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,

int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages)
{
- return perf_evlist__mmap_ex(evlist, pages, 0, false, 0);
+ return perf_evlist__mmap_ex(evlist, pages, 0, false, 0, 1);
}

int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 868294491194..33af704e55a2 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -162,7 +162,7 @@ unsigned long perf_event_mlock_kb_in_pages(void);

int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,
unsigned int auxtrace_pages,
- bool auxtrace_overwrite, int nr_cblocks);
+ bool auxtrace_overwrite, int nr_cblocks, int flush);
int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages);
void perf_evlist__munmap(struct perf_evlist *evlist);

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index dec6d218c31c..37ab460b6f06 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1463,6 +1463,23 @@ static int write_mem_topology(struct feat_fd *ff __maybe_unused,
return ret;
}

+static int write_compressed(struct feat_fd *ff __maybe_unused,
+ struct perf_evlist *evlist __maybe_unused)
+{
+ int ret;
+ u64 compression_info = ((u64)ff->ph->env.comp_type << 32) |
+ ff->ph->env.comp_level;
+
+ ret = do_write(ff, &compression_info, sizeof(compression_info));
+ if (ret)
+ return ret;
+
+ compression_info = ((u64)ff->ph->env.comp_ratio << 32) |
+ ff->ph->env.comp_mmap_len;
+
+ return do_write(ff, &compression_info, sizeof(compression_info));
+}
+
static void print_hostname(struct feat_fd *ff, FILE *fp)
{
fprintf(fp, "# hostname : %s\n", ff->ph->env.hostname);
@@ -1750,6 +1767,13 @@ 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: ";
@@ -2592,6 +2616,26 @@ static int process_clockid(struct feat_fd *ff,
return 0;
}

+static int process_compressed(struct feat_fd *ff,
+ void *data __maybe_unused)
+{
+ u64 compression_info;
+
+ if (do_read_u64(ff, &compression_info))
+ return -1;
+
+ ff->ph->env.comp_type = (compression_info >> 32) & 0xffffffffULL;
+ ff->ph->env.comp_level = compression_info & 0xffffffffULL;
+
+ if (do_read_u64(ff, &compression_info))
+ return -1;
+
+ ff->ph->env.comp_ratio = (compression_info >> 32) & 0xffffffffULL;
+ ff->ph->env.comp_mmap_len = compression_info & 0xffffffffULL;
+
+ return 0;
+}
+
struct feature_ops {
int (*write)(struct feat_fd *ff, struct perf_evlist *evlist);
void (*print)(struct feat_fd *ff, FILE *fp);
@@ -2651,7 +2695,8 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
FEAT_OPN(CACHE, cache, true),
FEAT_OPR(SAMPLE_TIME, sample_time, false),
FEAT_OPR(MEM_TOPOLOGY, mem_topology, true),
- FEAT_OPR(CLOCKID, clockid, false)
+ FEAT_OPR(CLOCKID, clockid, 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 0d553ddca0a3..ee867075dc64 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -39,6 +39,7 @@ enum {
HEADER_SAMPLE_TIME,
HEADER_MEM_TOPOLOGY,
HEADER_CLOCKID,
+ HEADER_COMPRESSED,
HEADER_LAST_FEATURE,
HEADER_FEAT_BITS = 256,
};
diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
index 8fc39311a30d..5e71b0183e33 100644
--- a/tools/perf/util/mmap.c
+++ b/tools/perf/util/mmap.c
@@ -347,6 +347,8 @@ int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd, int c
&mp->auxtrace_mp, map->base, fd))
return -1;

+ map->flush = mp->flush;
+
return perf_mmap__aio_mmap(map, mp);
}

@@ -395,7 +397,7 @@ static int __perf_mmap__read_init(struct perf_mmap *md)
md->start = md->overwrite ? head : old;
md->end = md->overwrite ? old : head;

- if (md->start == md->end)
+ if ((md->end - md->start) < md->flush)
return -EAGAIN;

size = md->end - md->start;
diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
index aeb6942fdb00..afbfb8b58d45 100644
--- a/tools/perf/util/mmap.h
+++ b/tools/perf/util/mmap.h
@@ -30,6 +30,7 @@ struct perf_mmap {
bool overwrite;
struct auxtrace_mmap auxtrace_mmap;
char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8);
+ u64 flush;
#ifdef HAVE_AIO_SUPPORT
struct {
void **data;
@@ -69,7 +70,7 @@ enum bkw_mmap_state {
};

struct mmap_params {
- int prot, mask, nr_cblocks;
+ int prot, mask, nr_cblocks, flush;
struct auxtrace_mmap_params auxtrace_mp;
};