perf list: Give more details about raw event encodings

List all the PMUs, not just the first core one, and list real format
specifiers with value ranges.

Before:

$ perf list
...
rNNN [Raw hardware event descriptor]
cpu/t1=v1[,t2=v2,t3 ...]/modifier [Raw hardware event descriptor]
[(see 'man perf-list' on how to encode it)]
mem:<addr>[/len][:access] [Hardware breakpoint]
...

After:

$ perf list
...
rNNN [Raw event descriptor]
cpu/event=0..255,pc,edge,.../modifier [Raw event descriptor]
[(see 'man perf-list' or 'man perf-record' on how to encode it)]
breakpoint//modifier [Raw event descriptor]
cstate_core/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
cstate_pkg/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
i915/i915_eventid=0..0x1fffff/modifier [Raw event descriptor]
intel_bts//modifier [Raw event descriptor]
intel_pt/ptw,event,cyc_thresh=0..15,.../modifier [Raw event descriptor]
kprobe/retprobe/modifier [Raw event descriptor]
msr/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
power/event=0..255/modifier [Raw event descriptor]
software//modifier [Raw event descriptor]
tracepoint//modifier [Raw event descriptor]
uncore_arb/event=0..255,edge,inv,.../modifier [Raw event descriptor]
uncore_cbox/event=0..255,edge,inv,.../modifier [Raw event descriptor]
uncore_clock/event=0..255/modifier [Raw event descriptor]
uncore_imc_free_running/event=0..255,umask=0..255/modifier[Raw event descriptor]
uprobe/ref_ctr_offset=0..0xffffffff,retprobe/modifier[Raw event descriptor]
mem:<addr>[/len][:access] [Hardware breakpoint]
...

With '--details' provide more details on the formats encoding:

cpu/event=0..255,pc,edge,.../modifier [Raw event descriptor]
[(see 'man perf-list' or 'man perf-record' on how to encode it)]
cpu/event=0..255,pc,edge,offcore_rsp=0..0xffffffffffffffff,ldlat=0..0xffff,inv,
umask=0..255,frontend=0..0xffffff,cmask=0..255,config=0..0xffffffffffffffff,
config1=0..0xffffffffffffffff,config2=0..0xffffffffffffffff,config3=0..0xffffffffffffffff,
name=string,period=number,freq=number,branch_type=(u|k|hv|any|...),time,
call-graph=(fp|dwarf|lbr),stack-size=number,max-stack=number,nr=number,inherit,no-inherit,
overwrite,no-overwrite,percore,aux-output,aux-sample-size=number/modifier
breakpoint//modifier [Raw event descriptor]
breakpoint//modifier
cstate_core/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
cstate_core/event=0..0xffffffffffffffff/modifier
cstate_pkg/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
cstate_pkg/event=0..0xffffffffffffffff/modifier
i915/i915_eventid=0..0x1fffff/modifier [Raw event descriptor]
i915/i915_eventid=0..0x1fffff/modifier
intel_bts//modifier [Raw event descriptor]
intel_bts//modifier
intel_pt/ptw,event,cyc_thresh=0..15,.../modifier [Raw event descriptor]
intel_pt/ptw,event,cyc_thresh=0..15,pt,notnt,branch,tsc,pwr_evt,fup_on_ptw,cyc,noretcomp,
mtc,psb_period=0..15,mtc_period=0..15/modifier
kprobe/retprobe/modifier [Raw event descriptor]
kprobe/retprobe/modifier
msr/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
msr/event=0..0xffffffffffffffff/modifier
power/event=0..255/modifier [Raw event descriptor]
power/event=0..255/modifier
software//modifier [Raw event descriptor]
software//modifier
tracepoint//modifier [Raw event descriptor]
tracepoint//modifier
uncore_arb/event=0..255,edge,inv,.../modifier [Raw event descriptor]
uncore_arb/event=0..255,edge,inv,umask=0..255,cmask=0..31/modifier
uncore_cbox/event=0..255,edge,inv,.../modifier [Raw event descriptor]
uncore_cbox/event=0..255,edge,inv,umask=0..255,cmask=0..31/modifier
uncore_clock/event=0..255/modifier [Raw event descriptor]
uncore_clock/event=0..255/modifier
uncore_imc_free_running/event=0..255,umask=0..255/modifier[Raw event descriptor]
uncore_imc_free_running/event=0..255,umask=0..255/modifier
uprobe/ref_ctr_offset=0..0xffffffff,retprobe/modifier[Raw event descriptor]
uprobe/ref_ctr_offset=0..0xffffffff,retprobe/modifier

Committer notes:

Address this build error in various distros:

55 58.44 ubuntu:24.04 : FAIL gcc version 13.2.0 (Ubuntu 13.2.0-17ubuntu2)
util/pmu.c:1638:70: error: '_Static_assert' with no message is a C2x extension [-Werror,-Wc2x-extensions]
1638 | _Static_assert(ARRAY_SIZE(terms) == __PARSE_EVENTS__TERM_TYPE_NR - 6);
| ^
| , ""
1 error generated.

Signed-off-by: Ian Rogers <[e-mail]>
Tested-by: Arnaldo Carvalho de Melo <[e-mail]>
Tested-by: Kan Liang <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: James Clark <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Ravi Bangoria <[e-mail]>
Cc: Yang Jihong <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/pmu.c

···
 	return false;
 }
 
+int perf_pmu__for_each_format(struct perf_pmu *pmu, void *state, pmu_format_callback cb)
+{
+	static const char *const terms[] = {
+		"config=0..0xffffffffffffffff",
+		"config1=0..0xffffffffffffffff",
+		"config2=0..0xffffffffffffffff",
+		"config3=0..0xffffffffffffffff",
+		"name=string",
+		"period=number",
+		"freq=number",
+		"branch_type=(u|k|hv|any|...)",
+		"time",
+		"call-graph=(fp|dwarf|lbr)",
+		"stack-size=number",
+		"max-stack=number",
+		"nr=number",
+		"inherit",
+		"no-inherit",
+		"overwrite",
+		"no-overwrite",
+		"percore",
+		"aux-output",
+		"aux-sample-size=number",
+	};
+	struct perf_pmu_format *format;
+	int ret;
+
+	/*
+	 * max-events and driver-config are missing above as are the internal
+	 * types user, metric-id, raw, legacy cache and hardware. Assert against
+	 * the enum parse_events__term_type so they are kept in sync.
+	 */
+	_Static_assert(ARRAY_SIZE(terms) == __PARSE_EVENTS__TERM_TYPE_NR - 6,
+		       "perf_pmu__for_each_format()'s terms must be kept in sync with enum parse_events__term_type");
+	list_for_each_entry(format, &pmu->format, list) {
+		perf_pmu_format__load(pmu, format);
+		ret = cb(state, format->name, (int)format->value, format->bits);
+		if (ret)
+			return ret;
+	}
+	if (!pmu->is_core)
+		return 0;
+
+	for (size_t i = 0; i < ARRAY_SIZE(terms); i++) {
+		int config = PERF_PMU_FORMAT_VALUE_CONFIG;
+
+		if (i < PERF_PMU_FORMAT_VALUE_CONFIG_END)
+			config = i;
+
+		ret = cb(state, terms[i], config, /*bits=*/NULL);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
 bool is_pmu_core(const char *name)
 {
 	return !strcmp(name, "cpu") || !strcmp(name, "cpum_cf") || is_sysfs_pmu_core(name);
···
 	pmu_add_cpu_aliases(pmu);
 	list_for_each_entry(event, &pmu->aliases, list) {
 		size_t buf_used;
+		int pmu_name_len;
 
 		info.pmu_name = event->pmu_name ?: pmu->name;
+		pmu_name_len = skip_duplicate_pmus
+			? pmu_name_len_no_suffix(info.pmu_name, /*num=*/NULL)
+			: (int)strlen(info.pmu_name);
 		info.alias = NULL;
 		if (event->desc) {
 			info.name = event->name;
···
 		info.encoding_desc = buf + buf_used;
 		parse_events_terms__to_strbuf(&event->terms, &sb);
 		buf_used += snprintf(buf + buf_used, sizeof(buf) - buf_used,
-				"%s/%s/", info.pmu_name, sb.buf) + 1;
+				"%.*s/%s/", pmu_name_len, info.pmu_name, sb.buf) + 1;
 		info.topic = event->topic;
 		info.str = sb.buf;
 		info.deprecated = event->deprecated;

tools/perf/util/pmu.h

···
 };
 
 typedef int (*pmu_event_callback)(void *state, struct pmu_event_info *info);
+typedef int (*pmu_format_callback)(void *state, const char *name, int config,
+				   const unsigned long *bits);
 
 void pmu_add_sys_aliases(struct perf_pmu *pmu);
 int perf_pmu__config(struct perf_pmu *pmu, struct perf_event_attr *attr,
···
 int perf_pmu__format_parse(struct perf_pmu *pmu, int dirfd, bool eager_load);
 void perf_pmu_format__set_value(void *format, int config, unsigned long *bits);
 bool perf_pmu__has_format(const struct perf_pmu *pmu, const char *name);
+int perf_pmu__for_each_format(struct perf_pmu *pmu, void *state, pmu_format_callback cb);
 
 bool is_pmu_core(const char *name);
 bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu);

tools/perf/util/pmus.c

···
 #include "pmus.h"
 #include "pmu.h"
 #include "print-events.h"
+#include "strbuf.h"
 
 /*
  * core_pmus:  A PMU belongs to core_pmus if it's name is "cpu" or it's sysfs
···
 		printf("\n");
 
 	zfree(&aliases);
+}
+
+struct build_format_string_args {
+	struct strbuf short_string;
+	struct strbuf long_string;
+	int num_formats;
+};
+
+static int build_format_string(void *state, const char *name, int config,
+			       const unsigned long *bits)
+{
+	struct build_format_string_args *args = state;
+	unsigned int num_bits;
+	int ret1, ret2 = 0;
+
+	(void)config;
+	args->num_formats++;
+	if (args->num_formats > 1) {
+		strbuf_addch(&args->long_string, ',');
+		if (args->num_formats < 4)
+			strbuf_addch(&args->short_string, ',');
+	}
+	num_bits = bits ? bitmap_weight(bits, PERF_PMU_FORMAT_BITS) : 0;
+	if (num_bits <= 1) {
+		ret1 = strbuf_addf(&args->long_string, "%s", name);
+		if (args->num_formats < 4)
+			ret2 = strbuf_addf(&args->short_string, "%s", name);
+	} else if (num_bits > 8) {
+		ret1 = strbuf_addf(&args->long_string, "%s=0..0x%llx", name,
+				   ULLONG_MAX >> (64 - num_bits));
+		if (args->num_formats < 4) {
+			ret2 = strbuf_addf(&args->short_string, "%s=0..0x%llx", name,
+					   ULLONG_MAX >> (64 - num_bits));
+		}
+	} else {
+		ret1 = strbuf_addf(&args->long_string, "%s=0..%llu", name,
+				  ULLONG_MAX >> (64 - num_bits));
+		if (args->num_formats < 4) {
+			ret2 = strbuf_addf(&args->short_string, "%s=0..%llu", name,
+					   ULLONG_MAX >> (64 - num_bits));
+		}
+	}
+	return ret1 < 0 ? ret1 : (ret2 < 0 ? ret2 : 0);
+}
+
+void perf_pmus__print_raw_pmu_events(const struct print_callbacks *print_cb, void *print_state)
+{
+	bool skip_duplicate_pmus = print_cb->skip_duplicate_pmus(print_state);
+	struct perf_pmu *(*scan_fn)(struct perf_pmu *);
+	struct perf_pmu *pmu = NULL;
+
+	if (skip_duplicate_pmus)
+		scan_fn = perf_pmus__scan_skip_duplicates;
+	else
+		scan_fn = perf_pmus__scan;
+
+	while ((pmu = scan_fn(pmu)) != NULL) {
+		struct build_format_string_args format_args = {
+			.short_string = STRBUF_INIT,
+			.long_string = STRBUF_INIT,
+			.num_formats = 0,
+		};
+		int len = pmu_name_len_no_suffix(pmu->name, /*num=*/NULL);
+		const char *desc = "(see 'man perf-list' or 'man perf-record' on how to encode it)";
+
+		if (!pmu->is_core)
+			desc = NULL;
+
+		strbuf_addf(&format_args.short_string, "%.*s/", len, pmu->name);
+		strbuf_addf(&format_args.long_string, "%.*s/", len, pmu->name);
+		perf_pmu__for_each_format(pmu, &format_args, build_format_string);
+
+		if (format_args.num_formats > 3)
+			strbuf_addf(&format_args.short_string, ",.../modifier");
+		else
+			strbuf_addf(&format_args.short_string, "/modifier");
+
+		strbuf_addf(&format_args.long_string, "/modifier");
+		print_cb->print_event(print_state,
+				/*topic=*/NULL,
+				/*pmu_name=*/NULL,
+				format_args.short_string.buf,
+				/*event_alias=*/NULL,
+				/*scale_unit=*/NULL,
+				/*deprecated=*/false,
+				"Raw event descriptor",
+				desc,
+				/*long_desc=*/NULL,
+				format_args.long_string.buf);
+
+		strbuf_release(&format_args.short_string);
+		strbuf_release(&format_args.long_string);
+	}
 }
 
 bool perf_pmus__have_event(const char *pname, const char *name)

tools/perf/util/pmus.h

···
 const struct perf_pmu *perf_pmus__pmu_for_pmu_filter(const char *str);
 
 void perf_pmus__print_pmu_events(const struct print_callbacks *print_cb, void *print_state);
+void perf_pmus__print_raw_pmu_events(const struct print_callbacks *print_cb, void *print_state);
 bool perf_pmus__have_event(const char *pname, const char *name);
 int perf_pmus__num_core_pmus(void);
 bool perf_pmus__supports_extended_type(void);

tools/perf/util/print-events.c

···
 	"Software event",
 	"Tracepoint event",
 	"Hardware cache event",
-	"Raw hardware event descriptor",
+	"Raw event descriptor",
 	"Hardware breakpoint",
 };
 
···
  */
 void print_events(const struct print_callbacks *print_cb, void *print_state)
 {
-	char *tmp;
-
 	print_symbol_events(print_cb, print_state, PERF_TYPE_HARDWARE,
 			event_symbols_hw, PERF_COUNT_HW_MAX);
 	print_symbol_events(print_cb, print_state, PERF_TYPE_SOFTWARE,
···
 			/*long_desc=*/NULL,
 			/*encoding_desc=*/NULL);
 
-	if (asprintf(&tmp, "%s/t1=v1[,t2=v2,t3 ...]/modifier",
-		     perf_pmus__scan_core(/*pmu=*/NULL)->name) > 0) {
-		print_cb->print_event(print_state,
-				/*topic=*/NULL,
-				/*pmu_name=*/NULL,
-				tmp,
-				/*event_alias=*/NULL,
-				/*scale_unit=*/NULL,
-				/*deprecated=*/false,
-				event_type_descriptors[PERF_TYPE_RAW],
-				"(see 'man perf-list' on how to encode it)",
-				/*long_desc=*/NULL,
-				/*encoding_desc=*/NULL);
-		free(tmp);
-	}
+	perf_pmus__print_raw_pmu_events(print_cb, print_state);
 
 	print_cb->print_event(print_state,
 			/*topic=*/NULL,