Re: [PATCH v1] perf jevents: Drop or simplify small integer values

From: Liang, Kan
Date: Wed Jan 31 2024 - 16:30:56 EST




On 2024-01-31 3:14 p.m., Ian Rogers wrote:
> Prior to this patch '0' would be dropped as the config values default
> to 0. Some json values are hex and the string '0' wouldn't match '0x0'
> as zero. Add a more robust is_zero test to drop these event terms.
>
> When encoding numbers as hex, if the number is between 0 and 9
> inclusive then don't add a 0x prefix.
>
> Update test expectations for these changes.
>
> On x86 this reduces the event/metric C string by 58,411 bytes.
>
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>

Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

Thanks,
Kan
> ---
> tools/perf/pmu-events/jevents.py | 23 ++++++++++++++++++++---
> tools/perf/tests/pmu-events.c | 22 +++++++++++-----------
> 2 files changed, 31 insertions(+), 14 deletions(-)
>
> diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
> index 53ab050c8fa4..2c7e5d61ce92 100755
> --- a/tools/perf/pmu-events/jevents.py
> +++ b/tools/perf/pmu-events/jevents.py
> @@ -203,7 +203,7 @@ class JsonEvent:
>
> def llx(x: int) -> str:
> """Convert an int to a string similar to a printf modifier of %#llx."""
> - return '0' if x == 0 else hex(x)
> + return str(x) if x >= 0 and x < 10 else hex(x)
>
> def fixdesc(s: str) -> str:
> """Fix formatting issue for the desc string."""
> @@ -294,6 +294,23 @@ class JsonEvent:
> }
> return table[unit] if unit in table else f'uncore_{unit.lower()}'
>
> + def is_zero(val: str) -> bool:
> + try:
> + if val.startswith('0x'):
> + return int(val, 16) == 0
> + else:
> + return int(val) == 0
> + except e:
> + return False
> +
> + def canonicalize_value(val: str) -> str:
> + try:
> + if val.startswith('0x'):
> + return llx(int(val, 16))
> + return str(int(val))
> + except e:
> + return val
> +
> eventcode = 0
> if 'EventCode' in jd:
> eventcode = int(jd['EventCode'].split(',', 1)[0], 0)
> @@ -358,8 +375,8 @@ class JsonEvent:
> ('RdWrMask', 'rdwrmask='),
> ]
> for key, value in event_fields:
> - if key in jd and jd[key] != '0':
> - event += ',' + value + jd[key]
> + if key in jd and not is_zero(jd[key]):
> + event += f',{value}{canonicalize_value(jd[key])}'
> if filter:
> event += f',{filter}'
> if msr:
> diff --git a/tools/perf/tests/pmu-events.c b/tools/perf/tests/pmu-events.c
> index a56d32905743..47a7c3277540 100644
> --- a/tools/perf/tests/pmu-events.c
> +++ b/tools/perf/tests/pmu-events.c
> @@ -70,7 +70,7 @@ static const struct perf_pmu_test_event segment_reg_loads_any = {
> .event = {
> .pmu = "default_core",
> .name = "segment_reg_loads.any",
> - .event = "event=0x6,period=200000,umask=0x80",
> + .event = "event=6,period=200000,umask=0x80",
> .desc = "Number of segment register loads",
> .topic = "other",
> },
> @@ -82,7 +82,7 @@ static const struct perf_pmu_test_event dispatch_blocked_any = {
> .event = {
> .pmu = "default_core",
> .name = "dispatch_blocked.any",
> - .event = "event=0x9,period=200000,umask=0x20",
> + .event = "event=9,period=200000,umask=0x20",
> .desc = "Memory cluster signals to block micro-op dispatch for any reason",
> .topic = "other",
> },
> @@ -94,11 +94,11 @@ static const struct perf_pmu_test_event eist_trans = {
> .event = {
> .pmu = "default_core",
> .name = "eist_trans",
> - .event = "event=0x3a,period=200000,umask=0x0",
> + .event = "event=0x3a,period=200000",
> .desc = "Number of Enhanced Intel SpeedStep(R) Technology (EIST) transitions",
> .topic = "other",
> },
> - .alias_str = "event=0x3a,period=0x30d40,umask=0",
> + .alias_str = "event=0x3a,period=0x30d40",
> .alias_long_desc = "Number of Enhanced Intel SpeedStep(R) Technology (EIST) transitions",
> };
>
> @@ -128,7 +128,7 @@ static const struct perf_pmu_test_event *core_events[] = {
> static const struct perf_pmu_test_event uncore_hisi_ddrc_flux_wcmd = {
> .event = {
> .name = "uncore_hisi_ddrc.flux_wcmd",
> - .event = "event=0x2",
> + .event = "event=2",
> .desc = "DDRC write commands",
> .topic = "uncore",
> .long_desc = "DDRC write commands",
> @@ -156,13 +156,13 @@ static const struct perf_pmu_test_event unc_cbo_xsnp_response_miss_eviction = {
> static const struct perf_pmu_test_event uncore_hyphen = {
> .event = {
> .name = "event-hyphen",
> - .event = "event=0xe0,umask=0x00",
> + .event = "event=0xe0",
> .desc = "UNC_CBO_HYPHEN",
> .topic = "uncore",
> .long_desc = "UNC_CBO_HYPHEN",
> .pmu = "uncore_cbox",
> },
> - .alias_str = "event=0xe0,umask=0",
> + .alias_str = "event=0xe0",
> .alias_long_desc = "UNC_CBO_HYPHEN",
> .matching_pmu = "uncore_cbox_0",
> };
> @@ -170,13 +170,13 @@ static const struct perf_pmu_test_event uncore_hyphen = {
> static const struct perf_pmu_test_event uncore_two_hyph = {
> .event = {
> .name = "event-two-hyph",
> - .event = "event=0xc0,umask=0x00",
> + .event = "event=0xc0",
> .desc = "UNC_CBO_TWO_HYPH",
> .topic = "uncore",
> .long_desc = "UNC_CBO_TWO_HYPH",
> .pmu = "uncore_cbox",
> },
> - .alias_str = "event=0xc0,umask=0",
> + .alias_str = "event=0xc0",
> .alias_long_desc = "UNC_CBO_TWO_HYPH",
> .matching_pmu = "uncore_cbox_0",
> };
> @@ -184,7 +184,7 @@ static const struct perf_pmu_test_event uncore_two_hyph = {
> static const struct perf_pmu_test_event uncore_hisi_l3c_rd_hit_cpipe = {
> .event = {
> .name = "uncore_hisi_l3c.rd_hit_cpipe",
> - .event = "event=0x7",
> + .event = "event=7",
> .desc = "Total read hits",
> .topic = "uncore",
> .long_desc = "Total read hits",
> @@ -265,7 +265,7 @@ static const struct perf_pmu_test_event sys_ccn_pmu_read_cycles = {
> static const struct perf_pmu_test_event sys_cmn_pmu_hnf_cache_miss = {
> .event = {
> .name = "sys_cmn_pmu.hnf_cache_miss",
> - .event = "eventid=0x1,type=0x5",
> + .event = "eventid=1,type=5",
> .desc = "Counts total cache misses in first lookup result (high priority)",
> .topic = "uncore",
> .pmu = "uncore_sys_cmn_pmu",