Commit ab443998 authored by Sami Tolvanen's avatar Sami Tolvanen Committed by Masahiro Yamada
Browse files

gendwarfksyms: Add symtypes output 



Add support for producing genksyms-style symtypes files. Process
die_map to find the longest expansions for each type, and use symtypes
references in type definitions. The basic file format is similar to
genksyms, with two notable exceptions:

  1. Type names with spaces (common with Rust) in references are
     wrapped in single quotes. E.g.:

     s#'core::result::Result<u8, core::num::error::ParseIntError>'

  2. The actual type definition is the simple parsed DWARF format we
     output with --dump-dies, not the preprocessed C-style format
     genksyms produces.

Signed-off-by: default avatarSami Tolvanen <samitolvanen@google.com>
Reviewed-by: default avatarPetr Pavlu <petr.pavlu@suse.com>
Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
parent d2ffdc1c

scripts/gendwarfksyms/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -6,5 +6,6 @@ gendwarfksyms-objs += cache.o 
gendwarfksyms-objs += die.o

gendwarfksyms-objs += dwarf.o

gendwarfksyms-objs += symbols.o

gendwarfksyms-objs += types.o



HOSTLDLIBS_gendwarfksyms := -ldw -lelf

scripts/gendwarfksyms/die.c

+11 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ static inline unsigned int die_hash(uintptr_t addr, enum die_state state) 
static void init_die(struct die *cd)

{

	cd->state = DIE_INCOMPLETE;

	cd->mapped = false;

	cd->fqn = NULL;

	cd->tag = -1;

	cd->addr = 0;
@@ -83,6 +84,16 @@ static void reset_die(struct die *cd) 
	init_die(cd);

}



void die_map_for_each(die_map_callback_t func, void *arg)

{

	struct hlist_node *tmp;

	struct die *cd;



	hash_for_each_safe(die_map, cd, tmp, hash) {

		func(cd, arg);

	}

}



void die_map_free(void)

{

	struct hlist_node *tmp;

scripts/gendwarfksyms/dwarf.c

+1 −0
Original line number Diff line number Diff line
@@ -745,6 +745,7 @@ static void process_symbol(struct state *state, Dwarf_Die *die, 
{

	debug("%s", state->sym->name);

	check(process_func(state, NULL, die));

	state->sym->state = SYMBOL_MAPPED;

	if (dump_dies)

		fputs("\n", stderr);

}

scripts/gendwarfksyms/gendwarfksyms.c

+31 −2
Original line number Diff line number Diff line
@@ -21,6 +21,11 @@ int debug; 
int dump_dies;

/* Print debugging information about die_map changes */

int dump_die_map;

/* Print out type strings (i.e. type_map) */

int dump_types;

/* Write a symtypes file */

int symtypes;

static const char *symtypes_file;



static void usage(void)

{
@@ -29,6 +34,8 @@ static void usage(void) 
	      "  -d, --debug          Print debugging information\n"

	      "      --dump-dies      Dump DWARF DIE contents\n"

	      "      --dump-die-map   Print debugging information about die_map changes\n"

	      "      --dump-types     Dump type strings\n"

	      "  -T, --symtypes file  Write a symtypes file\n"

	      "  -h, --help           Print this message\n"

	      "\n",

	      stderr);
@@ -41,6 +48,7 @@ static int process_module(Dwfl_Module *mod, void **userdata, const char *name, 
	Dwarf_Die cudie;

	Dwarf_CU *cu = NULL;

	Dwarf *dbg;

	FILE *symfile = arg;

	int res;



	debug("%s", name);
@@ -60,6 +68,10 @@ static int process_module(Dwfl_Module *mod, void **userdata, const char *name, 
		process_cu(&cudie);

	} while (cu);



	/*

	 * Use die_map to expand type strings and write them to `symfile`.

	 */

	generate_symtypes(symfile);

	die_map_free();



	return DWARF_CB_OK;
@@ -72,6 +84,7 @@ static const Dwfl_Callbacks callbacks = { 


int main(int argc, char **argv)

{

	FILE *symfile = NULL;

	unsigned int n;

	int opt;
@@ -79,17 +92,23 @@ int main(int argc, char **argv) 
		{ "debug", 0, NULL, 'd' },

		{ "dump-dies", 0, &dump_dies, 1 },

		{ "dump-die-map", 0, &dump_die_map, 1 },

		{ "dump-types", 0, &dump_types, 1 },

		{ "symtypes", 1, NULL, 'T' },

		{ "help", 0, NULL, 'h' },

		{ 0, 0, NULL, 0 }

	};



	while ((opt = getopt_long(argc, argv, "dh", opts, NULL)) != EOF) {

	while ((opt = getopt_long(argc, argv, "dT:h", opts, NULL)) != EOF) {

		switch (opt) {

		case 0:

			break;

		case 'd':

			debug = 1;

			break;

		case 'T':

			symtypes = 1;

			symtypes_file = optarg;

			break;

		case 'h':

			usage();

			return 0;
@@ -109,6 +128,13 @@ int main(int argc, char **argv) 


	symbol_read_exports(stdin);



	if (symtypes_file) {

		symfile = fopen(symtypes_file, "w");

		if (!symfile)

			error("fopen failed for '%s': %s", symtypes_file,

			      strerror(errno));

	}



	for (n = optind; n < argc; n++) {

		Dwfl *dwfl;

		int fd;
@@ -131,12 +157,15 @@ int main(int argc, char **argv) 


		dwfl_report_end(dwfl, NULL, NULL);



		if (dwfl_getmodules(dwfl, &process_module, NULL, 0))

		if (dwfl_getmodules(dwfl, &process_module, symfile, 0))

			error("dwfl_getmodules failed for '%s'", argv[n]);



		dwfl_end(dwfl);

	}



	if (symfile)

		check(fclose(symfile));



	symbol_free();



	return 0;

scripts/gendwarfksyms/gendwarfksyms.h

+19 −0
Original line number Diff line number Diff line
@@ -22,6 +22,8 @@ 
extern int debug;

extern int dump_dies;

extern int dump_die_map;

extern int dump_types;

extern int symtypes;



/*

 * Output helpers
@@ -90,6 +92,11 @@ static inline unsigned int addr_hash(uintptr_t addr) 
	return hash_ptr((const void *)addr);

}



enum symbol_state {

	SYMBOL_UNPROCESSED,

	SYMBOL_MAPPED,

};



struct symbol_addr {

	uint32_t section;

	Elf64_Addr address;
@@ -100,6 +107,8 @@ struct symbol { 
	struct symbol_addr addr;

	struct hlist_node addr_hash;

	struct hlist_node name_hash;

	enum symbol_state state;

	uintptr_t die_addr;

};



typedef void (*symbol_callback_t)(struct symbol *, void *arg);
@@ -154,6 +163,7 @@ static inline const char *die_state_name(enum die_state state) 


struct die {

	enum die_state state;

	bool mapped;

	char *fqn;

	int tag;

	uintptr_t addr;
@@ -161,10 +171,13 @@ struct die { 
	struct hlist_node hash;

};



typedef void (*die_map_callback_t)(struct die *, void *arg);



int __die_map_get(uintptr_t addr, enum die_state state, struct die **res);

struct die *die_map_get(Dwarf_Die *die, enum die_state state);

void die_map_add_string(struct die *pd, const char *str);

void die_map_add_linebreak(struct die *pd, int linebreak);

void die_map_for_each(die_map_callback_t func, void *arg);

void die_map_add_die(struct die *pd, struct die *child);

void die_map_free(void);
@@ -235,4 +248,10 @@ int process_die_container(struct state *state, struct die *cache, 


void process_cu(Dwarf_Die *cudie);



/*

 * types.c

 */



void generate_symtypes(FILE *file);



#endif /* __GENDWARFKSYMS_H */