Commit 6f1b6291 authored by Namhyung Kim's avatar Namhyung Kim Committed by Arnaldo Carvalho de Melo
Browse files

perf tools: Add util/debuginfo.[ch] files 



Split debuginfo data structure and related functions into a separate
file so that it can be used by other components than the probe-finder.

Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231110000012.3538610-4-namhyung@kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent fb7fd2a1

tools/perf/util/Build

+1 −0
Original line number Diff line number Diff line
@@ -195,6 +195,7 @@ endif 
perf-$(CONFIG_DWARF) += probe-finder.o

perf-$(CONFIG_DWARF) += dwarf-aux.o

perf-$(CONFIG_DWARF) += dwarf-regs.o

perf-$(CONFIG_DWARF) += debuginfo.o



perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o

perf-$(CONFIG_LOCAL_LIBUNWIND)    += unwind-libunwind-local.o

tools/perf/util/debuginfo.c

0 → 100644
+205 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * DWARF debug information handling code.  Copied from probe-finder.c.

 *

 * Written by Masami Hiramatsu <mhiramat@redhat.com>

 */



#include <errno.h>

#include <fcntl.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <linux/zalloc.h>



#include "build-id.h"

#include "dso.h"

#include "debug.h"

#include "debuginfo.h"

#include "symbol.h"



#ifdef HAVE_DEBUGINFOD_SUPPORT

#include <elfutils/debuginfod.h>

#endif



/* Dwarf FL wrappers */

static char *debuginfo_path;	/* Currently dummy */



static const Dwfl_Callbacks offline_callbacks = {

	.find_debuginfo = dwfl_standard_find_debuginfo,

	.debuginfo_path = &debuginfo_path,



	.section_address = dwfl_offline_section_address,



	/* We use this table for core files too.  */

	.find_elf = dwfl_build_id_find_elf,

};



/* Get a Dwarf from offline image */

static int debuginfo__init_offline_dwarf(struct debuginfo *dbg,

					 const char *path)

{

	GElf_Addr dummy;

	int fd;



	fd = open(path, O_RDONLY);

	if (fd < 0)

		return fd;



	dbg->dwfl = dwfl_begin(&offline_callbacks);

	if (!dbg->dwfl)

		goto error;



	dwfl_report_begin(dbg->dwfl);

	dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd);

	if (!dbg->mod)

		goto error;



	dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias);

	if (!dbg->dbg)

		goto error;



	dwfl_module_build_id(dbg->mod, &dbg->build_id, &dummy);



	dwfl_report_end(dbg->dwfl, NULL, NULL);



	return 0;

error:

	if (dbg->dwfl)

		dwfl_end(dbg->dwfl);

	else

		close(fd);

	memset(dbg, 0, sizeof(*dbg));



	return -ENOENT;

}



static struct debuginfo *__debuginfo__new(const char *path)

{

	struct debuginfo *dbg = zalloc(sizeof(*dbg));

	if (!dbg)

		return NULL;



	if (debuginfo__init_offline_dwarf(dbg, path) < 0)

		zfree(&dbg);

	if (dbg)

		pr_debug("Open Debuginfo file: %s\n", path);

	return dbg;

}



enum dso_binary_type distro_dwarf_types[] = {

	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,

	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,

	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,

	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,

	DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,

	DSO_BINARY_TYPE__NOT_FOUND,

};



struct debuginfo *debuginfo__new(const char *path)

{

	enum dso_binary_type *type;

	char buf[PATH_MAX], nil = '\0';

	struct dso *dso;

	struct debuginfo *dinfo = NULL;

	struct build_id bid;



	/* Try to open distro debuginfo files */

	dso = dso__new(path);

	if (!dso)

		goto out;



	/* Set the build id for DSO_BINARY_TYPE__BUILDID_DEBUGINFO */

	if (is_regular_file(path) && filename__read_build_id(path, &bid) > 0)

		dso__set_build_id(dso, &bid);



	for (type = distro_dwarf_types;

	     !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND;

	     type++) {

		if (dso__read_binary_type_filename(dso, *type, &nil,

						   buf, PATH_MAX) < 0)

			continue;

		dinfo = __debuginfo__new(buf);

	}

	dso__put(dso);



out:

	/* if failed to open all distro debuginfo, open given binary */

	return dinfo ? : __debuginfo__new(path);

}



void debuginfo__delete(struct debuginfo *dbg)

{

	if (dbg) {

		if (dbg->dwfl)

			dwfl_end(dbg->dwfl);

		free(dbg);

	}

}



/* For the kernel module, we need a special code to get a DIE */

int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,

				bool adjust_offset)

{

	int n, i;

	Elf32_Word shndx;

	Elf_Scn *scn;

	Elf *elf;

	GElf_Shdr mem, *shdr;

	const char *p;



	elf = dwfl_module_getelf(dbg->mod, &dbg->bias);

	if (!elf)

		return -EINVAL;



	/* Get the number of relocations */

	n = dwfl_module_relocations(dbg->mod);

	if (n < 0)

		return -ENOENT;

	/* Search the relocation related .text section */

	for (i = 0; i < n; i++) {

		p = dwfl_module_relocation_info(dbg->mod, i, &shndx);

		if (strcmp(p, ".text") == 0) {

			/* OK, get the section header */

			scn = elf_getscn(elf, shndx);

			if (!scn)

				return -ENOENT;

			shdr = gelf_getshdr(scn, &mem);

			if (!shdr)

				return -ENOENT;

			*offs = shdr->sh_addr;

			if (adjust_offset)

				*offs -= shdr->sh_offset;

		}

	}

	return 0;

}



#ifdef HAVE_DEBUGINFOD_SUPPORT

int get_source_from_debuginfod(const char *raw_path,

			       const char *sbuild_id, char **new_path)

{

	debuginfod_client *c = debuginfod_begin();

	const char *p = raw_path;

	int fd;



	if (!c)

		return -ENOMEM;



	fd = debuginfod_find_source(c, (const unsigned char *)sbuild_id,

				0, p, new_path);

	pr_debug("Search %s from debuginfod -> %d\n", p, fd);

	if (fd >= 0)

		close(fd);

	debuginfod_end(c);

	if (fd < 0) {

		pr_debug("Failed to find %s in debuginfod (%s)\n",

			raw_path, sbuild_id);

		return -ENOENT;

	}

	pr_debug("Got a source %s\n", *new_path);



	return 0;

}

#endif /* HAVE_DEBUGINFOD_SUPPORT */

tools/perf/util/debuginfo.h

0 → 100644
+64 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-or-later */

#ifndef _PERF_DEBUGINFO_H

#define _PERF_DEBUGINFO_H



#include <errno.h>

#include <linux/compiler.h>



#ifdef HAVE_DWARF_SUPPORT



#include "dwarf-aux.h"



/* debug information structure */

struct debuginfo {

	Dwarf		*dbg;

	Dwfl_Module	*mod;

	Dwfl		*dwfl;

	Dwarf_Addr	bias;

	const unsigned char	*build_id;

};



/* This also tries to open distro debuginfo */

struct debuginfo *debuginfo__new(const char *path);

void debuginfo__delete(struct debuginfo *dbg);



int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,

			       bool adjust_offset);



#else /* HAVE_DWARF_SUPPORT */



/* dummy debug information structure */

struct debuginfo {

};



static inline struct debuginfo *debuginfo__new(const char *path __maybe_unused)

{

	return NULL;

}



static inline void debuginfo__delete(struct debuginfo *dbg __maybe_unused)

{

}



static inline int debuginfo__get_text_offset(struct debuginfo *dbg __maybe_unused,

					     Dwarf_Addr *offs __maybe_unused,

					     bool adjust_offset __maybe_unused)

{

	return -EINVAL;

}



#endif /* HAVE_DWARF_SUPPORT */



#ifdef HAVE_DEBUGINFOD_SUPPORT

int get_source_from_debuginfod(const char *raw_path, const char *sbuild_id,

			       char **new_path);

#else /* HAVE_DEBUGINFOD_SUPPORT */

static inline int get_source_from_debuginfod(const char *raw_path __maybe_unused,

					     const char *sbuild_id __maybe_unused,

					     char **new_path __maybe_unused)

{

	return -ENOTSUP;

}

#endif /* HAVE_DEBUGINFOD_SUPPORT */



#endif /* _PERF_DEBUGINFO_H */

tools/perf/util/probe-finder.c

+1 −192
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ 
#include "event.h"

#include "dso.h"

#include "debug.h"

#include "debuginfo.h"

#include "intlist.h"

#include "strbuf.h"

#include "strlist.h"
@@ -31,128 +32,9 @@ 
#include "probe-file.h"

#include "string2.h"



#ifdef HAVE_DEBUGINFOD_SUPPORT

#include <elfutils/debuginfod.h>

#endif



/* Kprobe tracer basic type is up to u64 */

#define MAX_BASIC_TYPE_BITS	64



/* Dwarf FL wrappers */

static char *debuginfo_path;	/* Currently dummy */



static const Dwfl_Callbacks offline_callbacks = {

	.find_debuginfo = dwfl_standard_find_debuginfo,

	.debuginfo_path = &debuginfo_path,



	.section_address = dwfl_offline_section_address,



	/* We use this table for core files too.  */

	.find_elf = dwfl_build_id_find_elf,

};



/* Get a Dwarf from offline image */

static int debuginfo__init_offline_dwarf(struct debuginfo *dbg,

					 const char *path)

{

	GElf_Addr dummy;

	int fd;



	fd = open(path, O_RDONLY);

	if (fd < 0)

		return fd;



	dbg->dwfl = dwfl_begin(&offline_callbacks);

	if (!dbg->dwfl)

		goto error;



	dwfl_report_begin(dbg->dwfl);

	dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd);

	if (!dbg->mod)

		goto error;



	dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias);

	if (!dbg->dbg)

		goto error;



	dwfl_module_build_id(dbg->mod, &dbg->build_id, &dummy);



	dwfl_report_end(dbg->dwfl, NULL, NULL);



	return 0;

error:

	if (dbg->dwfl)

		dwfl_end(dbg->dwfl);

	else

		close(fd);

	memset(dbg, 0, sizeof(*dbg));



	return -ENOENT;

}



static struct debuginfo *__debuginfo__new(const char *path)

{

	struct debuginfo *dbg = zalloc(sizeof(*dbg));

	if (!dbg)

		return NULL;



	if (debuginfo__init_offline_dwarf(dbg, path) < 0)

		zfree(&dbg);

	if (dbg)

		pr_debug("Open Debuginfo file: %s\n", path);

	return dbg;

}



enum dso_binary_type distro_dwarf_types[] = {

	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,

	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,

	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,

	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,

	DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,

	DSO_BINARY_TYPE__NOT_FOUND,

};



struct debuginfo *debuginfo__new(const char *path)

{

	enum dso_binary_type *type;

	char buf[PATH_MAX], nil = '\0';

	struct dso *dso;

	struct debuginfo *dinfo = NULL;

	struct build_id bid;



	/* Try to open distro debuginfo files */

	dso = dso__new(path);

	if (!dso)

		goto out;



	/* Set the build id for DSO_BINARY_TYPE__BUILDID_DEBUGINFO */

	if (is_regular_file(path) && filename__read_build_id(path, &bid) > 0)

		dso__set_build_id(dso, &bid);



	for (type = distro_dwarf_types;

	     !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND;

	     type++) {

		if (dso__read_binary_type_filename(dso, *type, &nil,

						   buf, PATH_MAX) < 0)

			continue;

		dinfo = __debuginfo__new(buf);

	}

	dso__put(dso);



out:

	/* if failed to open all distro debuginfo, open given binary */

	return dinfo ? : __debuginfo__new(path);

}



void debuginfo__delete(struct debuginfo *dbg)

{

	if (dbg) {

		if (dbg->dwfl)

			dwfl_end(dbg->dwfl);

		free(dbg);

	}

}



/*

 * Probe finder related functions

 */
@@ -1677,44 +1559,6 @@ int debuginfo__find_available_vars_at(struct debuginfo *dbg, 
	return (ret < 0) ? ret : af.nvls;

}



/* For the kernel module, we need a special code to get a DIE */

int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,

				bool adjust_offset)

{

	int n, i;

	Elf32_Word shndx;

	Elf_Scn *scn;

	Elf *elf;

	GElf_Shdr mem, *shdr;

	const char *p;



	elf = dwfl_module_getelf(dbg->mod, &dbg->bias);

	if (!elf)

		return -EINVAL;



	/* Get the number of relocations */

	n = dwfl_module_relocations(dbg->mod);

	if (n < 0)

		return -ENOENT;

	/* Search the relocation related .text section */

	for (i = 0; i < n; i++) {

		p = dwfl_module_relocation_info(dbg->mod, i, &shndx);

		if (strcmp(p, ".text") == 0) {

			/* OK, get the section header */

			scn = elf_getscn(elf, shndx);

			if (!scn)

				return -ENOENT;

			shdr = gelf_getshdr(scn, &mem);

			if (!shdr)

				return -ENOENT;

			*offs = shdr->sh_addr;

			if (adjust_offset)

				*offs -= shdr->sh_offset;

		}

	}

	return 0;

}



/* Reverse search */

int debuginfo__find_probe_point(struct debuginfo *dbg, u64 addr,

				struct perf_probe_point *ppt)
@@ -2009,41 +1853,6 @@ int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr) 
	return (ret < 0) ? ret : lf.found;

}



#ifdef HAVE_DEBUGINFOD_SUPPORT

/* debuginfod doesn't require the comp_dir but buildid is required */

static int get_source_from_debuginfod(const char *raw_path,

				const char *sbuild_id, char **new_path)

{

	debuginfod_client *c = debuginfod_begin();

	const char *p = raw_path;

	int fd;



	if (!c)

		return -ENOMEM;



	fd = debuginfod_find_source(c, (const unsigned char *)sbuild_id,

				0, p, new_path);

	pr_debug("Search %s from debuginfod -> %d\n", p, fd);

	if (fd >= 0)

		close(fd);

	debuginfod_end(c);

	if (fd < 0) {

		pr_debug("Failed to find %s in debuginfod (%s)\n",

			raw_path, sbuild_id);

		return -ENOENT;

	}

	pr_debug("Got a source %s\n", *new_path);



	return 0;

}

#else

static inline int get_source_from_debuginfod(const char *raw_path __maybe_unused,

				const char *sbuild_id __maybe_unused,

				char **new_path __maybe_unused)

{

	return -ENOTSUP;

}

#endif

/*

 * Find a src file from a DWARF tag path. Prepend optional source path prefix

 * and chop off leading directories that do not exist. Result is passed back as

tools/perf/util/probe-finder.h

+1 −18
Original line number Diff line number Diff line
@@ -24,21 +24,7 @@ static inline int is_c_varname(const char *name) 
#ifdef HAVE_DWARF_SUPPORT



#include "dwarf-aux.h"



/* TODO: export debuginfo data structure even if no dwarf support */



/* debug information structure */

struct debuginfo {

	Dwarf		*dbg;

	Dwfl_Module	*mod;

	Dwfl		*dwfl;

	Dwarf_Addr	bias;

	const unsigned char	*build_id;

};



/* This also tries to open distro debuginfo */

struct debuginfo *debuginfo__new(const char *path);

void debuginfo__delete(struct debuginfo *dbg);

#include "debuginfo.h"



/* Find probe_trace_events specified by perf_probe_event from debuginfo */

int debuginfo__find_trace_events(struct debuginfo *dbg,
@@ -49,9 +35,6 @@ int debuginfo__find_trace_events(struct debuginfo *dbg, 
int debuginfo__find_probe_point(struct debuginfo *dbg, u64 addr,

				struct perf_probe_point *ppt);



int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,

			       bool adjust_offset);



/* Find a line range */

int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr);