[PATCH v5 perf, bpf-next 5/7] perf util: handle PERF_RECORD_KSYMBOL

From: Song Liu
Date: Thu Dec 20 2018 - 13:29:16 EST

This patch handles PERF_RECORD_KSYMBOL in perf record/report.
Specifically, map and symbol are created for ksymbol register, and
removed for ksymbol unregister.

This patch also set perf_event_attr.ksymbol properly. The flag is
ON by default.

Signed-off-by: Song Liu <songliubraving@xxxxxx>
---
tools/perf/util/event.c | 20 ++++++++++++++
tools/perf/util/event.h | 18 +++++++++++++
tools/perf/util/evsel.c | 9 +++++++
tools/perf/util/evsel.h | 1 +
tools/perf/util/machine.c | 57 +++++++++++++++++++++++++++++++++++++++
tools/perf/util/machine.h | 5 +++-
tools/perf/util/session.c | 4 +++
tools/perf/util/tool.h | 4 ++-
8 files changed, 116 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index e9c108a6b1c3..4b47194eaa4b 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -24,6 +24,7 @@
#include "symbol/kallsyms.h"
#include "asm/bug.h"
#include "stat.h"
+#include "session.h"

static const char *perf_event__names[] = {
[0] = "TOTAL",
@@ -43,6 +44,7 @@ static const char *perf_event__names[] = {
[PERF_RECORD_SWITCH] = "SWITCH",
[PERF_RECORD_SWITCH_CPU_WIDE] = "SWITCH_CPU_WIDE",
[PERF_RECORD_NAMESPACES] = "NAMESPACES",
+ [PERF_RECORD_KSYMBOL] = "KSYMBOL",
[PERF_RECORD_HEADER_ATTR] = "ATTR",
[PERF_RECORD_HEADER_EVENT_TYPE] = "EVENT_TYPE",
[PERF_RECORD_HEADER_TRACING_DATA] = "TRACING_DATA",
@@ -1335,6 +1337,14 @@ int perf_event__process_switch(struct perf_tool *tool __maybe_unused,
return machine__process_switch_event(machine, event);
}

+int perf_event__process_ksymbol(struct perf_tool *tool __maybe_unused,
+ union perf_event *event,
+ struct perf_sample *sample __maybe_unused,
+ struct machine *machine)
+{
+ return machine__process_ksymbol(machine, event, sample);
+}
+
size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp)
{
return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %c %s\n",
@@ -1467,6 +1477,13 @@ static size_t perf_event__fprintf_lost(union perf_event *event, FILE *fp)
return fprintf(fp, " lost %" PRIu64 "\n", event->lost.lost);
}

+size_t perf_event__fprintf_ksymbol(union perf_event *event, FILE *fp)
+{
+ return fprintf(fp, " ksymbol event with addr %lx len %lu name %s\n",
+ event->ksymbol_event.addr, event->ksymbol_event.len,
+ event->ksymbol_event.name);
+}
+
size_t perf_event__fprintf(union perf_event *event, FILE *fp)
{
size_t ret = fprintf(fp, "PERF_RECORD_%s",
@@ -1502,6 +1519,9 @@ size_t perf_event__fprintf(union perf_event *event, FILE *fp)
case PERF_RECORD_LOST:
ret += perf_event__fprintf_lost(event, fp);
break;
+ case PERF_RECORD_KSYMBOL:
+ ret += perf_event__fprintf_ksymbol(event, fp);
+ break;
default:
ret += fprintf(fp, "\n");
}
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index bfa60bcafbde..100b59f1fdec 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -5,6 +5,7 @@
#include <limits.h>
#include <stdio.h>
#include <linux/kernel.h>
+#include <linux/bpf.h>

#include "../perf.h"
#include "build-id.h"
@@ -84,6 +85,17 @@ struct throttle_event {
u64 stream_id;
};

+#ifndef KSYM_NAME_LEN
+#define KSYM_NAME_LEN 256
+#endif
+
+struct ksymbol_event {
+ struct perf_event_header header;
+ u64 addr;
+ u64 len;
+ char name[KSYM_NAME_LEN];
+};
+
#define PERF_SAMPLE_MASK \
(PERF_SAMPLE_IP | PERF_SAMPLE_TID | \
PERF_SAMPLE_TIME | PERF_SAMPLE_ADDR | \
@@ -651,6 +663,7 @@ union perf_event {
struct stat_round_event stat_round;
struct time_conv_event time_conv;
struct feature_event feat;
+ struct ksymbol_event ksymbol_event;
};

void perf_event__print_totals(void);
@@ -750,6 +763,10 @@ int perf_event__process_exit(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample,
struct machine *machine);
+int perf_event__process_ksymbol(struct perf_tool *tool,
+ union perf_event *event,
+ struct perf_sample *sample,
+ struct machine *machine);
int perf_tool__process_synth_event(struct perf_tool *tool,
union perf_event *event,
struct machine *machine,
@@ -814,6 +831,7 @@ size_t perf_event__fprintf_switch(union perf_event *event, FILE *fp);
size_t perf_event__fprintf_thread_map(union perf_event *event, FILE *fp);
size_t perf_event__fprintf_cpu_map(union perf_event *event, FILE *fp);
size_t perf_event__fprintf_namespaces(union perf_event *event, FILE *fp);
+size_t perf_event__fprintf_ksymbol(union perf_event *event, FILE *fp);
size_t perf_event__fprintf(union perf_event *event, FILE *fp);

int kallsyms__get_function_start(const char *kallsyms_filename,
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index dbc0466db368..de34ce875648 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1035,6 +1035,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts,
attr->mmap = track;
attr->mmap2 = track && !perf_missing_features.mmap2;
attr->comm = track;
+ attr->ksymbol = track && !perf_missing_features.ksymbol;

if (opts->record_namespaces)
attr->namespaces = track;
@@ -1652,6 +1653,7 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
PRINT_ATTRf(context_switch, p_unsigned);
PRINT_ATTRf(write_backward, p_unsigned);
PRINT_ATTRf(namespaces, p_unsigned);
+ PRINT_ATTRf(ksymbol, p_unsigned);

PRINT_ATTRn("{ wakeup_events, wakeup_watermark }", wakeup_events, p_unsigned);
PRINT_ATTRf(bp_type, p_unsigned);
@@ -1811,6 +1813,8 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
PERF_SAMPLE_BRANCH_NO_CYCLES);
if (perf_missing_features.group_read && evsel->attr.inherit)
evsel->attr.read_format &= ~(PERF_FORMAT_GROUP|PERF_FORMAT_ID);
+ if (perf_missing_features.ksymbol)
+ evsel->attr.ksymbol = 0;
retry_sample_id:
if (perf_missing_features.sample_id_all)
evsel->attr.sample_id_all = 0;
@@ -1955,6 +1959,11 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
perf_missing_features.exclude_guest = true;
pr_debug2("switching off exclude_guest, exclude_host\n");
goto fallback_missing_features;
+ } else if (!perf_missing_features.ksymbol &&
+ evsel->attr.ksymbol) {
+ perf_missing_features.ksymbol = true;
+ pr_debug2("switching off ksymbol\n");
+ goto fallback_missing_features;
} else if (!perf_missing_features.sample_id_all) {
perf_missing_features.sample_id_all = true;
pr_debug2("switching off sample_id_all\n");
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 3147ca76c6fc..c647c1963f7a 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -168,6 +168,7 @@ struct perf_missing_features {
bool lbr_flags;
bool write_backward;
bool group_read;
+ bool ksymbol;
};

extern struct perf_missing_features perf_missing_features;
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 8f36ce813bc5..5b50442d77c9 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -681,6 +681,61 @@ int machine__process_switch_event(struct machine *machine __maybe_unused,
return 0;
}

+static int machine__process_ksymbol_register(
+ struct machine *machine,
+ union perf_event *event,
+ struct perf_sample *sample __maybe_unused)
+{
+ struct symbol *sym;
+ struct map *map;
+
+ map = map_groups__find(&machine->kmaps, event->ksymbol_event.addr);
+ if (!map) {
+ map = dso__new_map("bpf_prog");
+ if (!map)
+ return -ENOMEM;
+
+ map->start = event->ksymbol_event.addr;
+ map->pgoff = map->start;
+ map->end = map->start + event->ksymbol_event.len;
+ map_groups__insert(&machine->kmaps, map);
+ }
+
+ sym = symbol__new(event->ksymbol_event.addr, event->ksymbol_event.len,
+ 0, 0, event->ksymbol_event.name);
+ if (!sym)
+ return -ENOMEM;
+ dso__insert_symbol(map->dso, sym);
+ return 0;
+}
+
+static int machine__process_ksymbol_unregister(
+ struct machine *machine,
+ union perf_event *event,
+ struct perf_sample *sample __maybe_unused)
+{
+ struct map *map;
+
+ map = map_groups__find(&machine->kmaps, event->ksymbol_event.addr);
+ if (map)
+ map_groups__remove(&machine->kmaps, map);
+
+ return 0;
+}
+
+int machine__process_ksymbol(struct machine *machine __maybe_unused,
+ union perf_event *event,
+ struct perf_sample *sample)
+{
+ if (dump_trace)
+ perf_event__fprintf_ksymbol(event, stderr);
+
+ if (event->header.misc & PERF_RECORD_MISC_KSYMBOL_UNREGISTER)
+ return machine__process_ksymbol_unregister(machine, event,
+ sample);
+ return machine__process_ksymbol_register(machine, event, sample);
+}
+
static void dso__adjust_kmod_long_name(struct dso *dso, const char *filename)
{
const char *dup_filename;
@@ -1812,6 +1867,8 @@ int machine__process_event(struct machine *machine, union perf_event *event,
case PERF_RECORD_SWITCH:
case PERF_RECORD_SWITCH_CPU_WIDE:
ret = machine__process_switch_event(machine, event); break;
+ case PERF_RECORD_KSYMBOL:
+ ret = machine__process_ksymbol(machine, event, sample); break;
default:
ret = -1;
break;
diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h
index d856b85862e2..e92728fe66cd 100644
--- a/tools/perf/util/machine.h
+++ b/tools/perf/util/machine.h
@@ -127,9 +127,12 @@ int machine__process_mmap_event(struct machine *machine, union perf_event *event
struct perf_sample *sample);
int machine__process_mmap2_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample);
+
int machine__process_event(struct machine *machine, union perf_event *event,
struct perf_sample *sample);
-
+int machine__process_ksymbol(struct machine *machine,
+ union perf_event *event,
+ struct perf_sample *sample);
typedef void (*machine__process_t)(struct machine *machine, void *data);

struct machines {
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 7d2c8ce6cfad..2c1976a66164 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -371,6 +371,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool)
tool->itrace_start = perf_event__process_itrace_start;
if (tool->context_switch == NULL)
tool->context_switch = perf_event__process_switch;
+ if (tool->ksymbol == NULL)
+ tool->ksymbol = perf_event__process_ksymbol;
if (tool->read == NULL)
tool->read = process_event_sample_stub;
if (tool->throttle == NULL)
@@ -1300,6 +1302,8 @@ static int machines__deliver_event(struct machines *machines,
case PERF_RECORD_SWITCH:
case PERF_RECORD_SWITCH_CPU_WIDE:
return tool->context_switch(tool, event, sample, machine);
+ case PERF_RECORD_KSYMBOL:
+ return tool->ksymbol(tool, event, sample, machine);
default:
++evlist->stats.nr_unknown_events;
return -1;
diff --git a/tools/perf/util/tool.h b/tools/perf/util/tool.h
index 56e4ca54020a..9c81ca2f3cf7 100644
--- a/tools/perf/util/tool.h
+++ b/tools/perf/util/tool.h
@@ -53,7 +53,9 @@ struct perf_tool {
itrace_start,
context_switch,
throttle,
- unthrottle;
+ unthrottle,
+ ksymbol;
+
event_attr_op attr;
event_attr_op event_update;
event_op2 tracing_data;
--
2.17.1