Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf tooling updates from Thomas Gleixner:

 - handle uretprobe placement proper on little endian PPC64

 - fix buffer handling in libtraceevent

 - add a missing pointer derefence in perf probe

 - fix the build of host tools in cross builds

 - fix Intel PT timestamp handling

 - synchronize memcpy, cpufeatures and bpf headers with the kernel headers

 - support for vendor supplied JSON files describing PMU events

 - a new set of tool tips

 - initial work for clang/llvm support

 - address some style issues found by cppcheck

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
  tools build: Add feature detection for g++
  tools build: Support compiling C++ source file
  perf top/report: Add tips about a list option
  perf report/top: Add a tip about system-wide collection from all CPUs
  perf report/top: Add a tip about source line numbers with overhead
  tools: Synchronize tools/include/uapi/linux/bpf.h
  tools: Synchronize tools/arch/x86/include/asm/cpufeatures.h
  perf bench mem: Sync memcpy assembly sources with the kernel
  perf jevents: Fix Intel JSON fixed counter conversions
  tools lib traceevent: Fix kbuffer_read_at_offset()
  perf intel-pt: Fix MTC timestamp calculation for large MTC periods
  perf intel-pt: Fix estimated timestamps for cycle-accurate mode
  perf uretprobe ppc64le: Fix probe location
  perf pmu-events: Add Skylake frontend MSR support
  perf pmu-events: Fix fixed counters on Intel
  perf tools: Make alias matching case-insensitive
  perf tools: Allow period= in perf stat CPU event descriptions.
  perf tools: Add README for info on parsing JSON/map files
  perf list jevents: Add support for event list topics
  perf list: Support long jevents descriptions
  ...

1 files changed, 814 insertions, 0 deletions

diff --git a/tools/perf/pmu-events/jevents.c b/tools/perf/pmu-events/jevents.c
new file mode 100644
index 000000000000..41611d7f9873
--- /dev/null
+++ b/tools/perf/pmu-events/jevents.c
@@ -0,0 +1,814 @@
+#define  _XOPEN_SOURCE 500	/* needed for nftw() */
+#define  _GNU_SOURCE		/* needed for asprintf() */
+
+/* Parse event JSON files */
+
+/*
+ * Copyright (c) 2014, Intel Corporation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <libgen.h>
+#include <dirent.h>
+#include <sys/time.h>			/* getrlimit */
+#include <sys/resource.h>		/* getrlimit */
+#include <ftw.h>
+#include <sys/stat.h>
+#include "jsmn.h"
+#include "json.h"
+#include "jevents.h"
+
+#ifndef __maybe_unused
+#define __maybe_unused                  __attribute__((unused))
+#endif
+
+int verbose;
+char *prog;
+
+int eprintf(int level, int var, const char *fmt, ...)
+{
+
+	int ret;
+	va_list args;
+
+	if (var < level)
+		return 0;
+
+	va_start(args, fmt);
+
+	ret = vfprintf(stderr, fmt, args);
+
+	va_end(args);
+
+	return ret;
+}
+
+__attribute__((weak)) char *get_cpu_str(void)
+{
+	return NULL;
+}
+
+static void addfield(char *map, char **dst, const char *sep,
+		     const char *a, jsmntok_t *bt)
+{
+	unsigned int len = strlen(a) + 1 + strlen(sep);
+	int olen = *dst ? strlen(*dst) : 0;
+	int blen = bt ? json_len(bt) : 0;
+	char *out;
+
+	out = realloc(*dst, len + olen + blen);
+	if (!out) {
+		/* Don't add field in this case */
+		return;
+	}
+	*dst = out;
+
+	if (!olen)
+		*(*dst) = 0;
+	else
+		strcat(*dst, sep);
+	strcat(*dst, a);
+	if (bt)
+		strncat(*dst, map + bt->start, blen);
+}
+
+static void fixname(char *s)
+{
+	for (; *s; s++)
+		*s = tolower(*s);
+}
+
+static void fixdesc(char *s)
+{
+	char *e = s + strlen(s);
+
+	/* Remove trailing dots that look ugly in perf list */
+	--e;
+	while (e >= s && isspace(*e))
+		--e;
+	if (*e == '.')
+		*e = 0;
+}
+
+static struct msrmap {
+	const char *num;
+	const char *pname;
+} msrmap[] = {
+	{ "0x3F6", "ldlat=" },
+	{ "0x1A6", "offcore_rsp=" },
+	{ "0x1A7", "offcore_rsp=" },
+	{ "0x3F7", "frontend=" },
+	{ NULL, NULL }
+};
+
+static struct field {
+	const char *field;
+	const char *kernel;
+} fields[] = {
+	{ "EventCode",	"event=" },
+	{ "UMask",	"umask=" },
+	{ "CounterMask", "cmask=" },
+	{ "Invert",	"inv=" },
+	{ "AnyThread",	"any=" },
+	{ "EdgeDetect",	"edge=" },
+	{ "SampleAfterValue", "period=" },
+	{ NULL, NULL }
+};
+
+static void cut_comma(char *map, jsmntok_t *newval)
+{
+	int i;
+
+	/* Cut off everything after comma */
+	for (i = newval->start; i < newval->end; i++) {
+		if (map[i] == ',')
+			newval->end = i;
+	}
+}
+
+static int match_field(char *map, jsmntok_t *field, int nz,
+		       char **event, jsmntok_t *val)
+{
+	struct field *f;
+	jsmntok_t newval = *val;
+
+	for (f = fields; f->field; f++)
+		if (json_streq(map, field, f->field) && nz) {
+			cut_comma(map, &newval);
+			addfield(map, event, ",", f->kernel, &newval);
+			return 1;
+		}
+	return 0;
+}
+
+static struct msrmap *lookup_msr(char *map, jsmntok_t *val)
+{
+	jsmntok_t newval = *val;
+	static bool warned;
+	int i;
+
+	cut_comma(map, &newval);
+	for (i = 0; msrmap[i].num; i++)
+		if (json_streq(map, &newval, msrmap[i].num))
+			return &msrmap[i];
+	if (!warned) {
+		warned = true;
+		pr_err("%s: Unknown MSR in event file %.*s\n", prog,
+			json_len(val), map + val->start);
+	}
+	return NULL;
+}
+
+#define EXPECT(e, t, m) do { if (!(e)) {			\
+	jsmntok_t *loc = (t);					\
+	if (!(t)->start && (t) > tokens)			\
+		loc = (t) - 1;					\
+		pr_err("%s:%d: " m ", got %s\n", fn,		\
+			json_line(map, loc),			\
+			json_name(t));				\
+	goto out_free;						\
+} } while (0)
+
+#define TOPIC_DEPTH 256
+static char *topic_array[TOPIC_DEPTH];
+static int   topic_level;
+
+static char *get_topic(void)
+{
+	char *tp_old, *tp = NULL;
+	int i;
+
+	for (i = 0; i < topic_level + 1; i++) {
+		int n;
+
+		tp_old = tp;
+		n = asprintf(&tp, "%s%s", tp ?: "", topic_array[i]);
+		if (n < 0) {
+			pr_info("%s: asprintf() error %s\n", prog);
+			return NULL;
+		}
+		free(tp_old);
+	}
+
+	for (i = 0; i < (int) strlen(tp); i++) {
+		char c = tp[i];
+
+		if (c == '-')
+			tp[i] = ' ';
+		else if (c == '.') {
+			tp[i] = '\0';
+			break;
+		}
+	}
+
+	return tp;
+}
+
+static int add_topic(int level, char *bname)
+{
+	char *topic;
+
+	level -= 2;
+
+	if (level >= TOPIC_DEPTH)
+		return -EINVAL;
+
+	topic = strdup(bname);
+	if (!topic) {
+		pr_info("%s: strdup() error %s for file %s\n", prog,
+				strerror(errno), bname);
+		return -ENOMEM;
+	}
+
+	free(topic_array[topic_level]);
+	topic_array[topic_level] = topic;
+	topic_level              = level;
+	return 0;
+}
+
+struct perf_entry_data {
+	FILE *outfp;
+	char *topic;
+};
+
+static int close_table;
+
+static void print_events_table_prefix(FILE *fp, const char *tblname)
+{
+	fprintf(fp, "struct pmu_event %s[] = {\n", tblname);
+	close_table = 1;
+}
+
+static int print_events_table_entry(void *data, char *name, char *event,
+				    char *desc, char *long_desc)
+{
+	struct perf_entry_data *pd = data;
+	FILE *outfp = pd->outfp;
+	char *topic = pd->topic;
+
+	/*
+	 * TODO: Remove formatting chars after debugging to reduce
+	 *	 string lengths.
+	 */
+	fprintf(outfp, "{\n");
+
+	fprintf(outfp, "\t.name = \"%s\",\n", name);
+	fprintf(outfp, "\t.event = \"%s\",\n", event);
+	fprintf(outfp, "\t.desc = \"%s\",\n", desc);
+	fprintf(outfp, "\t.topic = \"%s\",\n", topic);
+	if (long_desc && long_desc[0])
+		fprintf(outfp, "\t.long_desc = \"%s\",\n", long_desc);
+
+	fprintf(outfp, "},\n");
+
+	return 0;
+}
+
+static void print_events_table_suffix(FILE *outfp)
+{
+	fprintf(outfp, "{\n");
+
+	fprintf(outfp, "\t.name = 0,\n");
+	fprintf(outfp, "\t.event = 0,\n");
+	fprintf(outfp, "\t.desc = 0,\n");
+
+	fprintf(outfp, "},\n");
+	fprintf(outfp, "};\n");
+	close_table = 0;
+}
+
+static struct fixed {
+	const char *name;
+	const char *event;
+} fixed[] = {
+	{ "inst_retired.any", "event=0xc0" },
+	{ "inst_retired.any_p", "event=0xc0" },
+	{ "cpu_clk_unhalted.ref", "event=0x0,umask=0x03" },
+	{ "cpu_clk_unhalted.thread", "event=0x3c" },
+	{ "cpu_clk_unhalted.thread_any", "event=0x3c,any=1" },
+	{ NULL, NULL},
+};
+
+/*
+ * Handle different fixed counter encodings between JSON and perf.
+ */
+static char *real_event(const char *name, char *event)
+{
+	int i;
+
+	for (i = 0; fixed[i].name; i++)
+		if (!strcasecmp(name, fixed[i].name))
+			return (char *)fixed[i].event;
+	return event;
+}
+
+/* Call func with each event in the json file */
+int json_events(const char *fn,
+	  int (*func)(void *data, char *name, char *event, char *desc,
+		      char *long_desc),
+	  void *data)
+{
+	int err = -EIO;
+	size_t size;
+	jsmntok_t *tokens, *tok;
+	int i, j, len;
+	char *map;
+
+	if (!fn)
+		return -ENOENT;
+
+	tokens = parse_json(fn, &map, &size, &len);
+	if (!tokens)
+		return -EIO;
+	EXPECT(tokens->type == JSMN_ARRAY, tokens, "expected top level array");
+	tok = tokens + 1;
+	for (i = 0; i < tokens->size; i++) {
+		char *event = NULL, *desc = NULL, *name = NULL;
+		char *long_desc = NULL;
+		char *extra_desc = NULL;
+		struct msrmap *msr = NULL;
+		jsmntok_t *msrval = NULL;
+		jsmntok_t *precise = NULL;
+		jsmntok_t *obj = tok++;
+
+		EXPECT(obj->type == JSMN_OBJECT, obj, "expected object");
+		for (j = 0; j < obj->size; j += 2) {
+			jsmntok_t *field, *val;
+			int nz;
+
+			field = tok + j;
+			EXPECT(field->type == JSMN_STRING, tok + j,
+			       "Expected field name");
+			val = tok + j + 1;
+			EXPECT(val->type == JSMN_STRING, tok + j + 1,
+			       "Expected string value");
+
+			nz = !json_streq(map, val, "0");
+			if (match_field(map, field, nz, &event, val)) {
+				/* ok */
+			} else if (json_streq(map, field, "EventName")) {
+				addfield(map, &name, "", "", val);
+			} else if (json_streq(map, field, "BriefDescription")) {
+				addfield(map, &desc, "", "", val);
+				fixdesc(desc);
+			} else if (json_streq(map, field,
+					     "PublicDescription")) {
+				addfield(map, &long_desc, "", "", val);
+				fixdesc(long_desc);
+			} else if (json_streq(map, field, "PEBS") && nz) {
+				precise = val;
+			} else if (json_streq(map, field, "MSRIndex") && nz) {
+				msr = lookup_msr(map, val);
+			} else if (json_streq(map, field, "MSRValue")) {
+				msrval = val;
+			} else if (json_streq(map, field, "Errata") &&
+				   !json_streq(map, val, "null")) {
+				addfield(map, &extra_desc, ". ",
+					" Spec update: ", val);
+			} else if (json_streq(map, field, "Data_LA") && nz) {
+				addfield(map, &extra_desc, ". ",
+					" Supports address when precise",
+					NULL);
+			}
+			/* ignore unknown fields */
+		}
+		if (precise && desc && !strstr(desc, "(Precise Event)")) {
+			if (json_streq(map, precise, "2"))
+				addfield(map, &extra_desc, " ",
+						"(Must be precise)", NULL);
+			else
+				addfield(map, &extra_desc, " ",
+						"(Precise event)", NULL);
+		}
+		if (desc && extra_desc)
+			addfield(map, &desc, " ", extra_desc, NULL);
+		if (long_desc && extra_desc)
+			addfield(map, &long_desc, " ", extra_desc, NULL);
+		if (msr != NULL)
+			addfield(map, &event, ",", msr->pname, msrval);
+		fixname(name);
+
+		err = func(data, name, real_event(name, event), desc, long_desc);
+		free(event);
+		free(desc);
+		free(name);
+		free(long_desc);
+		free(extra_desc);
+		if (err)
+			break;
+		tok += j;
+	}
+	EXPECT(tok - tokens == len, tok, "unexpected objects at end");
+	err = 0;
+out_free:
+	free_json(map, size, tokens);
+	return err;
+}
+
+static char *file_name_to_table_name(char *fname)
+{
+	unsigned int i;
+	int n;
+	int c;
+	char *tblname;
+
+	/*
+	 * Ensure tablename starts with alphabetic character.
+	 * Derive rest of table name from basename of the JSON file,
+	 * replacing hyphens and stripping out .json suffix.
+	 */
+	n = asprintf(&tblname, "pme_%s", basename(fname));
+	if (n < 0) {
+		pr_info("%s: asprintf() error %s for file %s\n", prog,
+				strerror(errno), fname);
+		return NULL;
+	}
+
+	for (i = 0; i < strlen(tblname); i++) {
+		c = tblname[i];
+
+		if (c == '-')
+			tblname[i] = '_';
+		else if (c == '.') {
+			tblname[i] = '\0';
+			break;
+		} else if (!isalnum(c) && c != '_') {
+			pr_err("%s: Invalid character '%c' in file name %s\n",
+					prog, c, basename(fname));
+			free(tblname);
+			tblname = NULL;
+			break;
+		}
+	}
+
+	return tblname;
+}
+
+static void print_mapping_table_prefix(FILE *outfp)
+{
+	fprintf(outfp, "struct pmu_events_map pmu_events_map[] = {\n");
+}
+
+static void print_mapping_table_suffix(FILE *outfp)
+{
+	/*
+	 * Print the terminating, NULL entry.
+	 */
+	fprintf(outfp, "{\n");
+	fprintf(outfp, "\t.cpuid = 0,\n");
+	fprintf(outfp, "\t.version = 0,\n");
+	fprintf(outfp, "\t.type = 0,\n");
+	fprintf(outfp, "\t.table = 0,\n");
+	fprintf(outfp, "},\n");
+
+	/* and finally, the closing curly bracket for the struct */
+	fprintf(outfp, "};\n");
+}
+
+static int process_mapfile(FILE *outfp, char *fpath)
+{
+	int n = 16384;
+	FILE *mapfp;
+	char *save = NULL;
+	char *line, *p;
+	int line_num;
+	char *tblname;
+
+	pr_info("%s: Processing mapfile %s\n", prog, fpath);
+
+	line = malloc(n);
+	if (!line)
+		return -1;
+
+	mapfp = fopen(fpath, "r");
+	if (!mapfp) {
+		pr_info("%s: Error %s opening %s\n", prog, strerror(errno),
+				fpath);
+		return -1;
+	}
+
+	print_mapping_table_prefix(outfp);
+
+	/* Skip first line (header) */
+	p = fgets(line, n, mapfp);
+	if (!p)
+		goto out;
+
+	line_num = 1;
+	while (1) {
+		char *cpuid, *version, *type, *fname;
+
+		line_num++;
+		p = fgets(line, n, mapfp);
+		if (!p)
+			break;
+
+		if (line[0] == '#' || line[0] == '\n')
+			continue;
+
+		if (line[strlen(line)-1] != '\n') {
+			/* TODO Deal with lines longer than 16K */
+			pr_info("%s: Mapfile %s: line %d too long, aborting\n",
+					prog, fpath, line_num);
+			return -1;
+		}
+		line[strlen(line)-1] = '\0';
+
+		cpuid = strtok_r(p, ",", &save);
+		version = strtok_r(NULL, ",", &save);
+		fname = strtok_r(NULL, ",", &save);
+		type = strtok_r(NULL, ",", &save);
+
+		tblname = file_name_to_table_name(fname);
+		fprintf(outfp, "{\n");
+		fprintf(outfp, "\t.cpuid = \"%s\",\n", cpuid);
+		fprintf(outfp, "\t.version = \"%s\",\n", version);
+		fprintf(outfp, "\t.type = \"%s\",\n", type);
+
+		/*
+		 * CHECK: We can't use the type (eg "core") field in the
+		 * table name. For us to do that, we need to somehow tweak
+		 * the other caller of file_name_to_table(), process_json()
+		 * to determine the type. process_json() file has no way
+		 * of knowing these are "core" events unless file name has
+		 * core in it. If filename has core in it, we can safely
+		 * ignore the type field here also.
+		 */
+		fprintf(outfp, "\t.table = %s\n", tblname);
+		fprintf(outfp, "},\n");
+	}
+
+out:
+	print_mapping_table_suffix(outfp);
+	return 0;
+}
+
+/*
+ * If we fail to locate/process JSON and map files, create a NULL mapping
+ * table. This would at least allow perf to build even if we can't find/use
+ * the aliases.
+ */
+static void create_empty_mapping(const char *output_file)
+{
+	FILE *outfp;
+
+	pr_info("%s: Creating empty pmu_events_map[] table\n", prog);
+
+	/* Truncate file to clear any partial writes to it */
+	outfp = fopen(output_file, "w");
+	if (!outfp) {
+		perror("fopen()");
+		_Exit(1);
+	}
+
+	fprintf(outfp, "#include \"../../pmu-events/pmu-events.h\"\n");
+	print_mapping_table_prefix(outfp);
+	print_mapping_table_suffix(outfp);
+	fclose(outfp);
+}
+
+static int get_maxfds(void)
+{
+	struct rlimit rlim;
+
+	if (getrlimit(RLIMIT_NOFILE, &rlim) == 0)
+		return min((int)rlim.rlim_max / 2, 512);
+
+	return 512;
+}
+
+/*
+ * nftw() doesn't let us pass an argument to the processing function,
+ * so use a global variables.
+ */
+static FILE *eventsfp;
+static char *mapfile;
+
+static int process_one_file(const char *fpath, const struct stat *sb,
+			    int typeflag, struct FTW *ftwbuf)
+{
+	char *tblname, *bname  = (char *) fpath + ftwbuf->base;
+	int is_dir  = typeflag == FTW_D;
+	int is_file = typeflag == FTW_F;
+	int level   = ftwbuf->level;
+	int err = 0;
+
+	pr_debug("%s %d %7jd %-20s %s\n",
+		 is_file ? "f" : is_dir ? "d" : "x",
+		 level, sb->st_size, bname, fpath);
+
+	/* base dir */
+	if (level == 0)
+		return 0;
+
+	/* model directory, reset topic */
+	if (level == 1 && is_dir) {
+		if (close_table)
+			print_events_table_suffix(eventsfp);
+
+		/*
+		 * Drop file name suffix. Replace hyphens with underscores.
+		 * Fail if file name contains any alphanum characters besides
+		 * underscores.
+		 */
+		tblname = file_name_to_table_name(bname);
+		if (!tblname) {
+			pr_info("%s: Error determining table name for %s\n", prog,
+				bname);
+			return -1;
+		}
+
+		print_events_table_prefix(eventsfp, tblname);
+		return 0;
+	}
+
+	/*
+	 * Save the mapfile name for now. We will process mapfile
+	 * after processing all JSON files (so we can write out the
+	 * mapping table after all PMU events tables).
+	 *
+	 * TODO: Allow for multiple mapfiles? Punt for now.
+	 */
+	if (level == 1 && is_file) {
+		if (!strncmp(bname, "mapfile.csv", 11)) {
+			if (mapfile) {
+				pr_info("%s: Many mapfiles? Using %s, ignoring %s\n",
+						prog, mapfile, fpath);
+			} else {
+				mapfile = strdup(fpath);
+			}
+			return 0;
+		}
+
+		pr_info("%s: Ignoring file %s\n", prog, fpath);
+		return 0;
+	}
+
+	/*
+	 * If the file name does not have a .json extension,
+	 * ignore it. It could be a readme.txt for instance.
+	 */
+	if (is_file) {
+		char *suffix = bname + strlen(bname) - 5;
+
+		if (strncmp(suffix, ".json", 5)) {
+			pr_info("%s: Ignoring file without .json suffix %s\n", prog,
+				fpath);
+			return 0;
+		}
+	}
+
+	if (level > 1 && add_topic(level, bname))
+		return -ENOMEM;
+
+	/*
+	 * Assume all other files are JSON files.
+	 *
+	 * If mapfile refers to 'power7_core.json', we create a table
+	 * named 'power7_core'. Any inconsistencies between the mapfile
+	 * and directory tree could result in build failure due to table
+	 * names not being found.
+	 *
+	 * Atleast for now, be strict with processing JSON file names.
+	 * i.e. if JSON file name cannot be mapped to C-style table name,
+	 * fail.
+	 */
+	if (is_file) {
+		struct perf_entry_data data = {
+			.topic = get_topic(),
+			.outfp = eventsfp,
+		};
+
+		err = json_events(fpath, print_events_table_entry, &data);
+
+		free(data.topic);
+	}
+
+	return err;
+}
+
+#ifndef PATH_MAX
+#define PATH_MAX	4096
+#endif
+
+/*
+ * Starting in directory 'start_dirname', find the "mapfile.csv" and
+ * the set of JSON files for the architecture 'arch'.
+ *
+ * From each JSON file, create a C-style "PMU events table" from the
+ * JSON file (see struct pmu_event).
+ *
+ * From the mapfile, create a mapping between the CPU revisions and
+ * PMU event tables (see struct pmu_events_map).
+ *
+ * Write out the PMU events tables and the mapping table to pmu-event.c.
+ *
+ * If unable to process the JSON or arch files, create an empty mapping
+ * table so we can continue to build/use  perf even if we cannot use the
+ * PMU event aliases.
+ */
+int main(int argc, char *argv[])
+{
+	int rc;
+	int maxfds;
+	char ldirname[PATH_MAX];
+
+	const char *arch;
+	const char *output_file;
+	const char *start_dirname;
+
+	prog = basename(argv[0]);
+	if (argc < 4) {
+		pr_err("Usage: %s <arch> <starting_dir> <output_file>\n", prog);
+		return 1;
+	}
+
+	arch = argv[1];
+	start_dirname = argv[2];
+	output_file = argv[3];
+
+	if (argc > 4)
+		verbose = atoi(argv[4]);
+
+	eventsfp = fopen(output_file, "w");
+	if (!eventsfp) {
+		pr_err("%s Unable to create required file %s (%s)\n",
+				prog, output_file, strerror(errno));
+		return 2;
+	}
+
+	/* Include pmu-events.h first */
+	fprintf(eventsfp, "#include \"../../pmu-events/pmu-events.h\"\n");
+
+	sprintf(ldirname, "%s/%s", start_dirname, arch);
+
+	/*
+	 * The mapfile allows multiple CPUids to point to the same JSON file,
+	 * so, not sure if there is a need for symlinks within the pmu-events
+	 * directory.
+	 *
+	 * For now, treat symlinks of JSON files as regular files and create
+	 * separate tables for each symlink (presumably, each symlink refers
+	 * to specific version of the CPU).
+	 */
+
+	maxfds = get_maxfds();
+	mapfile = NULL;
+	rc = nftw(ldirname, process_one_file, maxfds, 0);
+	if (rc && verbose) {
+		pr_info("%s: Error walking file tree %s\n", prog, ldirname);
+		goto empty_map;
+	} else if (rc) {
+		goto empty_map;
+	}
+
+	if (close_table)
+		print_events_table_suffix(eventsfp);
+
+	if (!mapfile) {
+		pr_info("%s: No CPU->JSON mapping?\n", prog);
+		goto empty_map;
+	}
+
+	if (process_mapfile(eventsfp, mapfile)) {
+		pr_info("%s: Error processing mapfile %s\n", prog, mapfile);
+		goto empty_map;
+	}
+
+	return 0;
+
+empty_map:
+	fclose(eventsfp);
+	create_empty_mapping(output_file);
+	return 0;
+}