[PATCH 6/9] perf report: Support instruction latency

From: kan . liang
Date: Tue Feb 02 2021 - 15:22:29 EST


From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

The instruction latency information can be recorded on some platforms,
e.g., the Intel Sapphire Rapids server. With both memory latency
(weight) and the new instruction latency information, users can easily
locate the expensive load instructions, and also understand the time
spent in different stages. The users can optimize their applications
in different pipeline stages.

The 'weight' field is shared among different architectures. Reusing the
'weight' field may impacts other architectures. Add a new field to store
the instruction latency.

Like the 'weight' support, introduce a 'ins_lat' for the global
instruction latency, and a 'local_ins_lat' for the local instruction
latency version.

Add new sort functions, INSTR Latency and Local INSTR Latency,
accordingly.

Add local_ins_lat to the default_mem_sort_order[].

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
tools/perf/Documentation/perf-report.txt | 6 +++-
tools/perf/util/event.h | 1 +
tools/perf/util/evsel.c | 4 ++-
tools/perf/util/hist.c | 12 ++++++--
tools/perf/util/hist.h | 2 ++
tools/perf/util/intel-pt.c | 5 ++--
tools/perf/util/session.c | 8 ++++--
tools/perf/util/sort.c | 47 +++++++++++++++++++++++++++++++-
tools/perf/util/sort.h | 3 ++
tools/perf/util/synthetic-events.c | 4 ++-
10 files changed, 81 insertions(+), 11 deletions(-)

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 826b5a9..0565b7c 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -108,6 +108,9 @@ OPTIONS
- period: Raw number of event count of sample
- time: Separate the samples by time stamp with the resolution specified by
--time-quantum (default 100ms). Specify with overhead and before it.
+ - ins_lat: Instruction latency in core cycles. This is the global
+ instruction latency
+ - local_ins_lat: Local instruction latency version

By default, comm, dso and symbol keys are used.
(i.e. --sort comm,dso,symbol)
@@ -154,7 +157,8 @@ OPTIONS
- blocked: reason of blocked load access for the data at the time of the sample

And the default sort keys are changed to local_weight, mem, sym, dso,
- symbol_daddr, dso_daddr, snoop, tlb, locked, blocked, see '--mem-mode'.
+ symbol_daddr, dso_daddr, snoop, tlb, locked, blocked, local_ins_lat,
+ see '--mem-mode'.

If the data file has tracepoint event(s), following (dynamic) sort keys
are also available:
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index ff403ea..5d50a49 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -141,6 +141,7 @@ struct perf_sample {
u16 insn_len;
u8 cpumode;
u16 misc;
+ u16 ins_lat;
bool no_hw_idx; /* No hw_idx collected in branch_stack */
char insn[MAX_INSN];
void *raw_data;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 0a2a307..24c0b59 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2337,8 +2337,10 @@ int evsel__parse_sample(struct evsel *evsel, union perf_event *event,
weight.full = *array;
if (type & PERF_SAMPLE_WEIGHT)
data->weight = weight.full;
- else
+ else {
data->weight = weight.var1_dw;
+ data->ins_lat = weight.var2_w;
+ }
array++;
}

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 6866ab0..8a432f8 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -209,6 +209,8 @@ void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
hists__new_col_len(hists, HISTC_LOCAL_WEIGHT, 12);
hists__new_col_len(hists, HISTC_GLOBAL_WEIGHT, 12);
hists__new_col_len(hists, HISTC_MEM_BLOCKED, 10);
+ hists__new_col_len(hists, HISTC_LOCAL_INS_LAT, 13);
+ hists__new_col_len(hists, HISTC_GLOBAL_INS_LAT, 13);
if (symbol_conf.nanosecs)
hists__new_col_len(hists, HISTC_TIME, 16);
else
@@ -286,12 +288,13 @@ static long hist_time(unsigned long htime)
}

static void he_stat__add_period(struct he_stat *he_stat, u64 period,
- u64 weight)
+ u64 weight, u64 ins_lat)
{

he_stat->period += period;
he_stat->weight += weight;
he_stat->nr_events += 1;
+ he_stat->ins_lat += ins_lat;
}

static void he_stat__add_stat(struct he_stat *dest, struct he_stat *src)
@@ -303,6 +306,7 @@ static void he_stat__add_stat(struct he_stat *dest, struct he_stat *src)
dest->period_guest_us += src->period_guest_us;
dest->nr_events += src->nr_events;
dest->weight += src->weight;
+ dest->ins_lat += src->ins_lat;
}

static void he_stat__decay(struct he_stat *he_stat)
@@ -591,6 +595,7 @@ static struct hist_entry *hists__findnew_entry(struct hists *hists,
int64_t cmp;
u64 period = entry->stat.period;
u64 weight = entry->stat.weight;
+ u64 ins_lat = entry->stat.ins_lat;
bool leftmost = true;

p = &hists->entries_in->rb_root.rb_node;
@@ -609,11 +614,11 @@ static struct hist_entry *hists__findnew_entry(struct hists *hists,

if (!cmp) {
if (sample_self) {
- he_stat__add_period(&he->stat, period, weight);
+ he_stat__add_period(&he->stat, period, weight, ins_lat);
hist_entry__add_callchain_period(he, period);
}
if (symbol_conf.cumulate_callchain)
- he_stat__add_period(he->stat_acc, period, weight);
+ he_stat__add_period(he->stat_acc, period, weight, ins_lat);

/*
* This mem info was allocated from sample__resolve_mem
@@ -723,6 +728,7 @@ __hists__add_entry(struct hists *hists,
.nr_events = 1,
.period = sample->period,
.weight = sample->weight,
+ .ins_lat = sample->ins_lat,
},
.parent = sym_parent,
.filtered = symbol__parent_filter(sym_parent) | al->filtered,
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 522486b..36bca33 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -72,6 +72,8 @@ enum hist_column {
HISTC_DSO_SIZE,
HISTC_SYMBOL_IPC,
HISTC_MEM_BLOCKED,
+ HISTC_LOCAL_INS_LAT,
+ HISTC_GLOBAL_INS_LAT,
HISTC_NR_COLS, /* Last entry */
};

diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index a929f6d..c9477d0 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -1871,9 +1871,10 @@ static int intel_pt_synth_pebs_sample(struct intel_pt_queue *ptq)
* cycles. Use latency >> 32 to distinguish the
* different format of the mem access latency field.
*/
- if (weight > 0)
+ if (weight > 0) {
sample.weight = weight & 0xffff;
- else
+ sample.ins_lat = items->mem_access_latency & 0xffff;
+ } else
sample.weight = items->mem_access_latency;
}
if (!sample.weight && items->has_tsx_aux_info) {
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index a35d8c2..330e591 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1297,8 +1297,12 @@ static void dump_sample(struct evsel *evsel, union perf_event *event,
if (sample_type & PERF_SAMPLE_STACK_USER)
stack_user__printf(&sample->user_stack);

- if (sample_type & PERF_SAMPLE_WEIGHT_TYPE)
- printf("... weight: %" PRIu64 "\n", sample->weight);
+ if (sample_type & PERF_SAMPLE_WEIGHT_TYPE) {
+ printf("... weight: %" PRIu64 "", sample->weight);
+ if (sample_type & PERF_SAMPLE_WEIGHT_STRUCT)
+ printf(",0x%"PRIx16"", sample->ins_lat);
+ printf("\n");
+ }

if (sample_type & PERF_SAMPLE_DATA_SRC)
printf(" . data_src: 0x%"PRIx64"\n", sample->data_src);
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 249a03c..e0529f2 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -36,7 +36,7 @@ const char default_parent_pattern[] = "^sys_|^do_page_fault";
const char *parent_pattern = default_parent_pattern;
const char *default_sort_order = "comm,dso,symbol";
const char default_branch_sort_order[] = "comm,dso_from,symbol_from,symbol_to,cycles";
-const char default_mem_sort_order[] = "local_weight,mem,sym,dso,symbol_daddr,dso_daddr,snoop,tlb,locked,blocked";
+const char default_mem_sort_order[] = "local_weight,mem,sym,dso,symbol_daddr,dso_daddr,snoop,tlb,locked,blocked,local_ins_lat";
const char default_top_sort_order[] = "dso,symbol";
const char default_diff_sort_order[] = "dso,symbol";
const char default_tracepoint_sort_order[] = "trace";
@@ -1365,6 +1365,49 @@ struct sort_entry sort_global_weight = {
.se_width_idx = HISTC_GLOBAL_WEIGHT,
};

+static u64 he_ins_lat(struct hist_entry *he)
+{
+ return he->stat.nr_events ? he->stat.ins_lat / he->stat.nr_events : 0;
+}
+
+static int64_t
+sort__local_ins_lat_cmp(struct hist_entry *left, struct hist_entry *right)
+{
+ return he_ins_lat(left) - he_ins_lat(right);
+}
+
+static int hist_entry__local_ins_lat_snprintf(struct hist_entry *he, char *bf,
+ size_t size, unsigned int width)
+{
+ return repsep_snprintf(bf, size, "%-*u", width, he_ins_lat(he));
+}
+
+struct sort_entry sort_local_ins_lat = {
+ .se_header = "Local INSTR Latency",
+ .se_cmp = sort__local_ins_lat_cmp,
+ .se_snprintf = hist_entry__local_ins_lat_snprintf,
+ .se_width_idx = HISTC_LOCAL_INS_LAT,
+};
+
+static int64_t
+sort__global_ins_lat_cmp(struct hist_entry *left, struct hist_entry *right)
+{
+ return left->stat.ins_lat - right->stat.ins_lat;
+}
+
+static int hist_entry__global_ins_lat_snprintf(struct hist_entry *he, char *bf,
+ size_t size, unsigned int width)
+{
+ return repsep_snprintf(bf, size, "%-*u", width, he->stat.ins_lat);
+}
+
+struct sort_entry sort_global_ins_lat = {
+ .se_header = "INSTR Latency",
+ .se_cmp = sort__global_ins_lat_cmp,
+ .se_snprintf = hist_entry__global_ins_lat_snprintf,
+ .se_width_idx = HISTC_GLOBAL_INS_LAT,
+};
+
struct sort_entry sort_mem_daddr_sym = {
.se_header = "Data Symbol",
.se_cmp = sort__daddr_cmp,
@@ -1770,6 +1813,8 @@ static struct sort_dimension common_sort_dimensions[] = {
DIM(SORT_CGROUP_ID, "cgroup_id", sort_cgroup_id),
DIM(SORT_SYM_IPC_NULL, "ipc_null", sort_sym_ipc_null),
DIM(SORT_TIME, "time", sort_time),
+ DIM(SORT_LOCAL_INS_LAT, "local_ins_lat", sort_local_ins_lat),
+ DIM(SORT_GLOBAL_INS_LAT, "ins_lat", sort_global_ins_lat),
};

#undef DIM
diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 2b2645b..c92ca15 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h
@@ -50,6 +50,7 @@ struct he_stat {
u64 period_guest_sys;
u64 period_guest_us;
u64 weight;
+ u64 ins_lat;
u32 nr_events;
};

@@ -229,6 +230,8 @@ enum sort_type {
SORT_CGROUP_ID,
SORT_SYM_IPC_NULL,
SORT_TIME,
+ SORT_LOCAL_INS_LAT,
+ SORT_GLOBAL_INS_LAT,

/* branch stack specific sort keys */
__SORT_BRANCH_STACK,
diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index bc16268..95401c9 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -1557,8 +1557,10 @@ int perf_event__synthesize_sample(union perf_event *event, u64 type, u64 read_fo

if (type & PERF_SAMPLE_WEIGHT_TYPE) {
*array = sample->weight;
- if (type & PERF_SAMPLE_WEIGHT_STRUCT)
+ if (type & PERF_SAMPLE_WEIGHT_STRUCT) {
*array &= 0xffffffff;
+ *array |= ((u64)sample->ins_lat << 32);
+ }
array++;
}

--
2.7.4