/*
   * Copyright (c) 2013 Google, Inc
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  /* Decode and dump U-Boot profiling information */
  
  #include <assert.h>
  #include <ctype.h>
  #include <limits.h>
  #include <regex.h>
  #include <stdarg.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  #include <sys/param.h>
  
  #include <compiler.h>
  #include <trace.h>
  
  #define MAX_LINE_LEN 500
  
  enum {
  	FUNCF_TRACE	= 1 << 0,	/* Include this function in trace */
  };
  
  struct func_info {
  	unsigned long offset;
  	const char *name;
  	unsigned long code_size;
  	unsigned long call_count;
  	unsigned flags;
  	/* the section this function is in */
  	struct objsection_info *objsection;
  };
  
  enum trace_line_type {
  	TRACE_LINE_INCLUDE,
  	TRACE_LINE_EXCLUDE,
  };
  
  struct trace_configline_info {
  	struct trace_configline_info *next;
  	enum trace_line_type type;
  	const char *name;	/* identifier name / wildcard */
  	regex_t regex;		/* Regex to use if name starts with / */
  };
  
  /* The contents of the trace config file */
  struct trace_configline_info *trace_config_head;
  
  struct func_info *func_list;
  int func_count;
  struct trace_call *call_list;
  int call_count;
  int verbose;	/* Verbosity level 0=none, 1=warn, 2=notice, 3=info, 4=debug */
  unsigned long text_offset;		/* text address of first function */
  
  static void outf(int level, const char *fmt, ...)
  		__attribute__ ((format (__printf__, 2, 3)));
  #define error(fmt, b...) outf(0, fmt, ##b)
  #define warn(fmt, b...) outf(1, fmt, ##b)
  #define notice(fmt, b...) outf(2, fmt, ##b)
  #define info(fmt, b...) outf(3, fmt, ##b)
  #define debug(fmt, b...) outf(4, fmt, ##b)
  
  
  static void outf(int level, const char *fmt, ...)
  {
  	if (verbose >= level) {
  		va_list args;
  
  		va_start(args, fmt);
  		vfprintf(stderr, fmt, args);
  		va_end(args);
  	}
  }
  
  static void usage(void)
  {
  	fprintf(stderr,
  		"Usage: proftool -cds -v3 <cmd> <profdata>
  "
  		"
  "
  		"Commands
  "
  		"   dump-ftrace\t\tDump out textual data in ftrace format
  "
  		"
  "
  		"Options:
  "
  		"   -m <map>\tSpecify Systen.map file
  "
  		"   -t <trace>\tSpecific trace data file (from U-Boot)
  "
  		"   -v <0-4>\tSpecify verbosity
  ");
  	exit(EXIT_FAILURE);
  }
  
  static int h_cmp_offset(const void *v1, const void *v2)
  {
  	const struct func_info *f1 = v1, *f2 = v2;
  
  	return (f1->offset / FUNC_SITE_SIZE) - (f2->offset / FUNC_SITE_SIZE);
  }
  
  static int read_system_map(FILE *fin)
  {
  	unsigned long offset, start = 0;
  	struct func_info *func;
  	char buff[MAX_LINE_LEN];
  	char symtype;
  	char symname[MAX_LINE_LEN + 1];
  	int linenum;
  	int alloced;
  
  	for (linenum = 1, alloced = func_count = 0;; linenum++) {
  		int fields = 0;
  
  		if (fgets(buff, sizeof(buff), fin))
  			fields = sscanf(buff, "%lx %c %100s
  ", &offset,
  				&symtype, symname);
  		if (fields == 2) {
  			continue;
  		} else if (feof(fin)) {
  			break;
  		} else if (fields < 2) {
  			error("Map file line %d: invalid format
  ", linenum);
  			return 1;
  		}
  
  		/* Must be a text symbol */
  		symtype = tolower(symtype);
  		if (symtype != 't' && symtype != 'w')
  			continue;
  
  		if (func_count == alloced) {
  			alloced += 256;
  			func_list = realloc(func_list,
  					sizeof(struct func_info) * alloced);
  			assert(func_list);
  		}
  		if (!func_count)
  			start = offset;
  
  		func = &func_list[func_count++];
  		memset(func, '\0', sizeof(*func));
  		func->offset = offset - start;
  		func->name = strdup(symname);
  		func->flags = FUNCF_TRACE;	/* trace by default */
  
  		/* Update previous function's code size */
  		if (func_count > 1)
  			func[-1].code_size = func->offset - func[-1].offset;
  	}
  	notice("%d functions found in map file
  ", func_count);
  	text_offset = start;
  	return 0;
  }
  
  static int read_data(FILE *fin, void *buff, int size)
  {
  	int err;
  
  	err = fread(buff, 1, size, fin);
  	if (!err)
  		return 1;
  	if (err != size) {
  		error("Cannot read profile file at pos %ld
  ", ftell(fin));
  		return -1;
  	}
  	return 0;
  }
  
  static struct func_info *find_func_by_offset(uint32_t offset)
  {
  	struct func_info key, *found;
  
  	key.offset = offset;
  	found = bsearch(&key, func_list, func_count, sizeof(struct func_info),
  			h_cmp_offset);
  
  	return found;
  }
  
  /* This finds the function which contains the given offset */
  static struct func_info *find_caller_by_offset(uint32_t offset)
  {
  	int low;	/* least function that could be a match */
  	int high;	/* greated function that could be a match */
  	struct func_info key;
  
  	low = 0;
  	high = func_count - 1;
  	key.offset = offset;
  	while (high > low + 1) {
  		int mid = (low + high) / 2;
  		int result;
  
  		result = h_cmp_offset(&key, &func_list[mid]);
  		if (result > 0)
  			low = mid;
  		else if (result < 0)
  			high = mid;
  		else
  			return &func_list[mid];
  	}
  
  	return low >= 0 ? &func_list[low] : NULL;
  }
  
  static int read_calls(FILE *fin, int count)
  {
  	struct trace_call *call_data;
  	int i;
  
  	notice("call count: %d
  ", count);
  	call_list = (struct trace_call *)calloc(count, sizeof(*call_data));
  	if (!call_list) {
  		error("Cannot allocate call_list
  ");
  		return -1;
  	}
  	call_count = count;
  
  	call_data = call_list;
  	for (i = 0; i < count; i++, call_data++) {
  		if (read_data(fin, call_data, sizeof(*call_data)))
  			return 1;
  	}
  	return 0;
  }
  
  static int read_profile(FILE *fin, int *not_found)
  {
  	struct trace_output_hdr hdr;
  
  	*not_found = 0;
  	while (!feof(fin)) {
  		int err;
  
  		err = read_data(fin, &hdr, sizeof(hdr));
  		if (err == 1)
  			break; /* EOF */
  		else if (err)
  			return 1;
  
  		switch (hdr.type) {
  		case TRACE_CHUNK_FUNCS:
  			/* Ignored at present */
  			break;
  
  		case TRACE_CHUNK_CALLS:
  			if (read_calls(fin, hdr.rec_count))
  				return 1;
  			break;
  		}
  	}
  	return 0;
  }
  
  static int read_map_file(const char *fname)
  {
  	FILE *fmap;
  	int err = 0;
  
  	fmap = fopen(fname, "r");
  	if (!fmap) {
  		error("Cannot open map file '%s'
  ", fname);
  		return 1;
  	}
  	if (fmap) {
  		err = read_system_map(fmap);
  		fclose(fmap);
  	}
  	return err;
  }
  
  static int read_profile_file(const char *fname)
  {
  	int not_found = INT_MAX;
  	FILE *fprof;
  	int err;
  
  	fprof = fopen(fname, "rb");
  	if (!fprof) {
  		error("Cannot open profile data file '%s'
  ",
  		      fname);
  		return 1;
  	} else {
  		err = read_profile(fprof, &not_found);
  		fclose(fprof);
  		if (err)
  			return err;
  
  		if (not_found) {
  			warn("%d profile functions could not be found in the map file - are you sure that your profile data and map file correspond?
  ",
  			     not_found);
  			return 1;
  		}
  	}
  	return 0;
  }
  
  static int regex_report_error(regex_t *regex, int err, const char *op,
  			      const char *name)
  {
  	char buf[200];
  
  	regerror(err, regex, buf, sizeof(buf));
  	error("Regex error '%s' in %s '%s'
  ", buf, op, name);
  	return -1;
  }
  
  static void check_trace_config_line(struct trace_configline_info *item)
  {
  	struct func_info *func, *end;
  	int err;
  
  	debug("Checking trace config line '%s'
  ", item->name);
  	for (func = func_list, end = func + func_count; func < end; func++) {
  		err = regexec(&item->regex, func->name, 0, NULL, 0);
  		debug("   - regex '%s', string '%s': %d
  ", item->name,
  		      func->name, err);
  		if (err == REG_NOMATCH)
  			continue;
  
  		if (err) {
  			regex_report_error(&item->regex, err, "match",
  					   item->name);
  			break;
  		}
  
  		/* It matches, so perform the action */
  		switch (item->type) {
  		case TRACE_LINE_INCLUDE:
  			info("      include %s at %lx
  ", func->name,
  			     text_offset + func->offset);
  			func->flags |= FUNCF_TRACE;
  			break;
  
  		case TRACE_LINE_EXCLUDE:
  			info("      exclude %s at %lx
  ", func->name,
  			     text_offset + func->offset);
  			func->flags &= ~FUNCF_TRACE;
  			break;
  		}
  	}
  }
  
  static void check_trace_config(void)
  {
  	struct trace_configline_info *line;
  
  	for (line = trace_config_head; line; line = line->next)
  		check_trace_config_line(line);
  }
  
  /**
   * Check the functions to see if they each have an objsection. If not, then
   * the linker must have eliminated them.
   */
  static void check_functions(void)
  {
  	struct func_info *func, *end;
  	unsigned long removed_code_size = 0;
  	int not_found = 0;
  
  	/* Look for missing functions */
  	for (func = func_list, end = func + func_count; func < end; func++) {
  		if (!func->objsection) {
  			removed_code_size += func->code_size;
  			not_found++;
  		}
  	}
  
  	/* Figure out what functions we want to trace */
  	check_trace_config();
  
  	warn("%d functions removed by linker, %ld code size
  ",
  	     not_found, removed_code_size);
  }
  
  static int read_trace_config(FILE *fin)
  {
  	char buff[200];
  	int linenum = 0;
  	struct trace_configline_info **tailp = &trace_config_head;
  
  	while (fgets(buff, sizeof(buff), fin)) {
  		int len = strlen(buff);
  		struct trace_configline_info *line;
  		char *saveptr;
  		char *s, *tok;
  		int err;
  
  		linenum++;
  		if (len && buff[len - 1] == '
  ')
  			buff[len - 1] = '\0';
  
  		/* skip blank lines and comments */
  		for (s = buff; *s == ' ' || *s == '\t'; s++)
  			;
  		if (!*s || *s == '#')
  			continue;
  
  		line = (struct trace_configline_info *)calloc(1,
  							      sizeof(*line));
  		if (!line) {
  			error("Cannot allocate config line
  ");
  			return -1;
  		}
  
  		tok = strtok_r(s, " \t", &saveptr);
  		if (!tok) {
  			error("Invalid trace config data on line %d
  ",
  			      linenum);
  			return -1;
  		}
  		if (0 == strcmp(tok, "include-func")) {
  			line->type = TRACE_LINE_INCLUDE;
  		} else if (0 == strcmp(tok, "exclude-func")) {
  			line->type = TRACE_LINE_EXCLUDE;
  		} else {
  			error("Unknown command in trace config data line %d
  ",
  			      linenum);
  			return -1;
  		}
  
  		tok = strtok_r(NULL, " \t", &saveptr);
  		if (!tok) {
  			error("Missing pattern in trace config data line %d
  ",
  			      linenum);
  			return -1;
  		}
  
  		err = regcomp(&line->regex, tok, REG_NOSUB);
  		if (err) {
  			free(line);
  			return regex_report_error(&line->regex, err, "compile",
  						  tok);
  		}
  
  		/* link this new one to the end of the list */
  		line->name = strdup(tok);
  		line->next = NULL;
  		*tailp = line;
  		tailp = &line->next;
  	}
  
  	if (!feof(fin)) {
  		error("Cannot read from trace config file at position %ld
  ",
  		      ftell(fin));
  		return -1;
  	}
  	return 0;
  }
  
  static int read_trace_config_file(const char *fname)
  {
  	FILE *fin;
  	int err;
  
  	fin = fopen(fname, "r");
  	if (!fin) {
  		error("Cannot open trace_config file '%s'
  ", fname);
  		return -1;
  	}
  	err = read_trace_config(fin);
  	fclose(fin);
  	return err;
  }
  
  static void out_func(ulong func_offset, int is_caller, const char *suffix)
  {
  	struct func_info *func;
  
  	func = (is_caller ? find_caller_by_offset : find_func_by_offset)
  		(func_offset);
  
  	if (func)
  		printf("%s%s", func->name, suffix);
  	else
  		printf("%lx%s", func_offset, suffix);
  }
  
  /*
   * # tracer: function
   * #
   * #           TASK-PID   CPU#    TIMESTAMP  FUNCTION
   * #              | |      |          |         |
   * #           bash-4251  [01] 10152.583854: path_put <-path_walk
   * #           bash-4251  [01] 10152.583855: dput <-path_put
   * #           bash-4251  [01] 10152.583855: _atomic_dec_and_lock <-dput
   */
  static int make_ftrace(void)
  {
  	struct trace_call *call;
  	int missing_count = 0, skip_count = 0;
  	int i;
  
  	printf("# tracer: ftrace
  "
  		"#
  "
  		"#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
  "
  		"#              | |      |          |         |
  ");
  	for (i = 0, call = call_list; i < call_count; i++, call++) {
  		struct func_info *func = find_func_by_offset(call->func);
  		ulong time = call->flags & FUNCF_TIMESTAMP_MASK;
  
  		if (TRACE_CALL_TYPE(call) != FUNCF_ENTRY &&
  		    TRACE_CALL_TYPE(call) != FUNCF_EXIT)
  			continue;
  		if (!func) {
  			warn("Cannot find function at %lx
  ",
  			     text_offset + call->func);
  			missing_count++;
  			continue;
  		}
  
  		if (!(func->flags & FUNCF_TRACE)) {
  			debug("Funcion '%s' is excluded from trace
  ",
  			      func->name);
  			skip_count++;
  			continue;
  		}
  
  		printf("%16s-%-5d [01] %lu.%06lu: ", "uboot", 1,
  		       time / 1000000, time % 1000000);
  
  		out_func(call->func, 0, " <- ");
  		out_func(call->caller, 1, "
  ");
  	}
  	info("ftrace: %d functions not found, %d excluded
  ", missing_count,
  	     skip_count);
  
  	return 0;
  }
  
  static int prof_tool(int argc, char * const argv[],
  		     const char *prof_fname, const char *map_fname,
  		     const char *trace_config_fname)
  {
  	int err = 0;
  
  	if (read_map_file(map_fname))
  		return -1;
  	if (prof_fname && read_profile_file(prof_fname))
  		return -1;
  	if (trace_config_fname && read_trace_config_file(trace_config_fname))
  		return -1;
  
  	check_functions();
  
  	for (; argc; argc--, argv++) {
  		const char *cmd = *argv;
  
  		if (0 == strcmp(cmd, "dump-ftrace"))
  			err = make_ftrace();
  		else
  			warn("Unknown command '%s'
  ", cmd);
  	}
  
  	return err;
  }
  
  int main(int argc, char *argv[])
  {
  	const char *map_fname = "System.map";
  	const char *prof_fname = NULL;
  	const char *trace_config_fname = NULL;
  	int opt;
  
  	verbose = 2;
  	while ((opt = getopt(argc, argv, "m:p:t:v:")) != -1) {
  		switch (opt) {
  		case 'm':
  			map_fname = optarg;
  			break;
  
  		case 'p':
  			prof_fname = optarg;
  			break;
  
  		case 't':
  			trace_config_fname = optarg;
  			break;
  
  		case 'v':
  			verbose = atoi(optarg);
  			break;
  
  		default:
  			usage();
  		}
  	}
  	argc -= optind; argv += optind;
  	if (argc < 1)
  		usage();
  
  	debug("Debug enabled
  ");
  	return prof_tool(argc, argv, prof_fname, map_fname,
  			 trace_config_fname);
  }