![Hyeoncheol Lee](/assets/img/avatar_default.png)
Before casting a type of a variable to string, convert_variable_type() confirms that the type is a pointer or an array. then if it is a pointer to char, it is casted to string. but in case of an array of char, it isn't Signed-off-by: H.C. Lee <hyc.lee@gmail.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/CANFS6bb75e8a_UtyAD9yF73hfXDy0N8tSjDz=a+Vna=Y8ORMHg@mail.gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1589 lines
39 KiB
C
1589 lines
39 KiB
C
/*
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* probe-finder.c : C expression to kprobe event converter
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*
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* Written by Masami Hiramatsu <mhiramat@redhat.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*
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*/
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#include <sys/utsname.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <errno.h>
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#include <stdio.h>
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#include <unistd.h>
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#include <getopt.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdarg.h>
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#include <dwarf-regs.h>
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#include <linux/bitops.h>
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#include "event.h"
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#include "debug.h"
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#include "util.h"
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#include "symbol.h"
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#include "probe-finder.h"
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/* Kprobe tracer basic type is up to u64 */
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#define MAX_BASIC_TYPE_BITS 64
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/* Line number list operations */
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/* Add a line to line number list */
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static int line_list__add_line(struct list_head *head, int line)
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{
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struct line_node *ln;
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struct list_head *p;
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/* Reverse search, because new line will be the last one */
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list_for_each_entry_reverse(ln, head, list) {
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if (ln->line < line) {
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p = &ln->list;
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goto found;
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} else if (ln->line == line) /* Already exist */
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return 1;
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}
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/* List is empty, or the smallest entry */
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p = head;
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found:
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pr_debug("line list: add a line %u\n", line);
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ln = zalloc(sizeof(struct line_node));
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if (ln == NULL)
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return -ENOMEM;
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ln->line = line;
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INIT_LIST_HEAD(&ln->list);
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list_add(&ln->list, p);
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return 0;
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}
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/* Check if the line in line number list */
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static int line_list__has_line(struct list_head *head, int line)
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{
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struct line_node *ln;
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/* Reverse search, because new line will be the last one */
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list_for_each_entry(ln, head, list)
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if (ln->line == line)
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return 1;
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return 0;
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}
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/* Init line number list */
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static void line_list__init(struct list_head *head)
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{
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INIT_LIST_HEAD(head);
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}
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/* Free line number list */
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static void line_list__free(struct list_head *head)
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{
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struct line_node *ln;
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while (!list_empty(head)) {
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ln = list_first_entry(head, struct line_node, list);
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list_del(&ln->list);
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free(ln);
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}
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}
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/* Dwarf FL wrappers */
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static char *debuginfo_path; /* Currently dummy */
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static const Dwfl_Callbacks offline_callbacks = {
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.find_debuginfo = dwfl_standard_find_debuginfo,
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.debuginfo_path = &debuginfo_path,
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.section_address = dwfl_offline_section_address,
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/* We use this table for core files too. */
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.find_elf = dwfl_build_id_find_elf,
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};
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/* Get a Dwarf from offline image */
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static int debuginfo__init_offline_dwarf(struct debuginfo *self,
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const char *path)
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{
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Dwfl_Module *mod;
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int fd;
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fd = open(path, O_RDONLY);
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if (fd < 0)
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return fd;
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self->dwfl = dwfl_begin(&offline_callbacks);
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if (!self->dwfl)
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goto error;
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mod = dwfl_report_offline(self->dwfl, "", "", fd);
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if (!mod)
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goto error;
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self->dbg = dwfl_module_getdwarf(mod, &self->bias);
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if (!self->dbg)
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goto error;
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return 0;
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error:
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if (self->dwfl)
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dwfl_end(self->dwfl);
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else
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close(fd);
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memset(self, 0, sizeof(*self));
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return -ENOENT;
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}
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#if _ELFUTILS_PREREQ(0, 148)
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/* This method is buggy if elfutils is older than 0.148 */
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static int __linux_kernel_find_elf(Dwfl_Module *mod,
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void **userdata,
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const char *module_name,
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Dwarf_Addr base,
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char **file_name, Elf **elfp)
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{
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int fd;
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const char *path = kernel_get_module_path(module_name);
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pr_debug2("Use file %s for %s\n", path, module_name);
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if (path) {
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fd = open(path, O_RDONLY);
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if (fd >= 0) {
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*file_name = strdup(path);
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return fd;
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}
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}
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/* If failed, try to call standard method */
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return dwfl_linux_kernel_find_elf(mod, userdata, module_name, base,
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file_name, elfp);
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}
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static const Dwfl_Callbacks kernel_callbacks = {
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.find_debuginfo = dwfl_standard_find_debuginfo,
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.debuginfo_path = &debuginfo_path,
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.find_elf = __linux_kernel_find_elf,
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.section_address = dwfl_linux_kernel_module_section_address,
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};
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/* Get a Dwarf from live kernel image */
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static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
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Dwarf_Addr addr)
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{
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self->dwfl = dwfl_begin(&kernel_callbacks);
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if (!self->dwfl)
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return -EINVAL;
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/* Load the kernel dwarves: Don't care the result here */
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dwfl_linux_kernel_report_kernel(self->dwfl);
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dwfl_linux_kernel_report_modules(self->dwfl);
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self->dbg = dwfl_addrdwarf(self->dwfl, addr, &self->bias);
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/* Here, check whether we could get a real dwarf */
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if (!self->dbg) {
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pr_debug("Failed to find kernel dwarf at %lx\n",
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(unsigned long)addr);
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dwfl_end(self->dwfl);
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memset(self, 0, sizeof(*self));
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return -ENOENT;
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}
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return 0;
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}
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#else
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/* With older elfutils, this just support kernel module... */
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static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
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Dwarf_Addr addr __maybe_unused)
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{
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const char *path = kernel_get_module_path("kernel");
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if (!path) {
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pr_err("Failed to find vmlinux path\n");
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return -ENOENT;
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}
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pr_debug2("Use file %s for debuginfo\n", path);
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return debuginfo__init_offline_dwarf(self, path);
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}
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#endif
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struct debuginfo *debuginfo__new(const char *path)
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{
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struct debuginfo *self = zalloc(sizeof(struct debuginfo));
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if (!self)
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return NULL;
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if (debuginfo__init_offline_dwarf(self, path) < 0) {
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free(self);
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self = NULL;
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}
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return self;
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}
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struct debuginfo *debuginfo__new_online_kernel(unsigned long addr)
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{
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struct debuginfo *self = zalloc(sizeof(struct debuginfo));
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if (!self)
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return NULL;
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if (debuginfo__init_online_kernel_dwarf(self, (Dwarf_Addr)addr) < 0) {
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free(self);
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self = NULL;
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}
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return self;
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}
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void debuginfo__delete(struct debuginfo *self)
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{
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if (self) {
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if (self->dwfl)
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dwfl_end(self->dwfl);
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free(self);
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}
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}
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/*
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* Probe finder related functions
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*/
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static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
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{
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struct probe_trace_arg_ref *ref;
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ref = zalloc(sizeof(struct probe_trace_arg_ref));
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if (ref != NULL)
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ref->offset = offs;
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return ref;
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}
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/*
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* Convert a location into trace_arg.
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* If tvar == NULL, this just checks variable can be converted.
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*/
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static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
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Dwarf_Op *fb_ops,
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struct probe_trace_arg *tvar)
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{
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Dwarf_Attribute attr;
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Dwarf_Op *op;
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size_t nops;
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unsigned int regn;
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Dwarf_Word offs = 0;
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bool ref = false;
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const char *regs;
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int ret;
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if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL)
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goto static_var;
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/* TODO: handle more than 1 exprs */
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if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL ||
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dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0 ||
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nops == 0) {
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/* TODO: Support const_value */
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return -ENOENT;
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}
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if (op->atom == DW_OP_addr) {
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static_var:
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if (!tvar)
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return 0;
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/* Static variables on memory (not stack), make @varname */
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ret = strlen(dwarf_diename(vr_die));
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tvar->value = zalloc(ret + 2);
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if (tvar->value == NULL)
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return -ENOMEM;
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snprintf(tvar->value, ret + 2, "@%s", dwarf_diename(vr_die));
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tvar->ref = alloc_trace_arg_ref((long)offs);
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if (tvar->ref == NULL)
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return -ENOMEM;
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return 0;
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}
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/* If this is based on frame buffer, set the offset */
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if (op->atom == DW_OP_fbreg) {
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if (fb_ops == NULL)
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return -ENOTSUP;
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ref = true;
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offs = op->number;
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op = &fb_ops[0];
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}
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if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
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regn = op->atom - DW_OP_breg0;
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offs += op->number;
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ref = true;
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} else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
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regn = op->atom - DW_OP_reg0;
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} else if (op->atom == DW_OP_bregx) {
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regn = op->number;
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offs += op->number2;
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ref = true;
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} else if (op->atom == DW_OP_regx) {
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regn = op->number;
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} else {
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pr_debug("DW_OP %x is not supported.\n", op->atom);
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return -ENOTSUP;
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}
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if (!tvar)
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return 0;
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regs = get_arch_regstr(regn);
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if (!regs) {
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/* This should be a bug in DWARF or this tool */
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pr_warning("Mapping for the register number %u "
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"missing on this architecture.\n", regn);
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return -ERANGE;
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}
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tvar->value = strdup(regs);
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if (tvar->value == NULL)
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return -ENOMEM;
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if (ref) {
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tvar->ref = alloc_trace_arg_ref((long)offs);
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if (tvar->ref == NULL)
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return -ENOMEM;
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}
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return 0;
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}
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#define BYTES_TO_BITS(nb) ((nb) * BITS_PER_LONG / sizeof(long))
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static int convert_variable_type(Dwarf_Die *vr_die,
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struct probe_trace_arg *tvar,
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const char *cast)
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{
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struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
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Dwarf_Die type;
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char buf[16];
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int bsize, boffs, total;
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int ret;
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/* TODO: check all types */
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if (cast && strcmp(cast, "string") != 0) {
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/* Non string type is OK */
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tvar->type = strdup(cast);
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return (tvar->type == NULL) ? -ENOMEM : 0;
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}
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bsize = dwarf_bitsize(vr_die);
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if (bsize > 0) {
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/* This is a bitfield */
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boffs = dwarf_bitoffset(vr_die);
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total = dwarf_bytesize(vr_die);
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if (boffs < 0 || total < 0)
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return -ENOENT;
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ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs,
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BYTES_TO_BITS(total));
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goto formatted;
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}
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if (die_get_real_type(vr_die, &type) == NULL) {
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pr_warning("Failed to get a type information of %s.\n",
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dwarf_diename(vr_die));
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return -ENOENT;
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}
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pr_debug("%s type is %s.\n",
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dwarf_diename(vr_die), dwarf_diename(&type));
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|
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if (cast && strcmp(cast, "string") == 0) { /* String type */
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ret = dwarf_tag(&type);
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if (ret != DW_TAG_pointer_type &&
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ret != DW_TAG_array_type) {
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pr_warning("Failed to cast into string: "
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"%s(%s) is not a pointer nor array.\n",
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dwarf_diename(vr_die), dwarf_diename(&type));
|
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return -EINVAL;
|
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}
|
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if (die_get_real_type(&type, &type) == NULL) {
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pr_warning("Failed to get a type"
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" information.\n");
|
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return -ENOENT;
|
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}
|
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if (ret == DW_TAG_pointer_type) {
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while (*ref_ptr)
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ref_ptr = &(*ref_ptr)->next;
|
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/* Add new reference with offset +0 */
|
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*ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
|
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if (*ref_ptr == NULL) {
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pr_warning("Out of memory error\n");
|
|
return -ENOMEM;
|
|
}
|
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}
|
|
if (!die_compare_name(&type, "char") &&
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!die_compare_name(&type, "unsigned char")) {
|
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pr_warning("Failed to cast into string: "
|
|
"%s is not (unsigned) char *.\n",
|
|
dwarf_diename(vr_die));
|
|
return -EINVAL;
|
|
}
|
|
tvar->type = strdup(cast);
|
|
return (tvar->type == NULL) ? -ENOMEM : 0;
|
|
}
|
|
|
|
ret = dwarf_bytesize(&type);
|
|
if (ret <= 0)
|
|
/* No size ... try to use default type */
|
|
return 0;
|
|
ret = BYTES_TO_BITS(ret);
|
|
|
|
/* Check the bitwidth */
|
|
if (ret > MAX_BASIC_TYPE_BITS) {
|
|
pr_info("%s exceeds max-bitwidth. Cut down to %d bits.\n",
|
|
dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
|
|
ret = MAX_BASIC_TYPE_BITS;
|
|
}
|
|
ret = snprintf(buf, 16, "%c%d",
|
|
die_is_signed_type(&type) ? 's' : 'u', ret);
|
|
|
|
formatted:
|
|
if (ret < 0 || ret >= 16) {
|
|
if (ret >= 16)
|
|
ret = -E2BIG;
|
|
pr_warning("Failed to convert variable type: %s\n",
|
|
strerror(-ret));
|
|
return ret;
|
|
}
|
|
tvar->type = strdup(buf);
|
|
if (tvar->type == NULL)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
|
|
struct perf_probe_arg_field *field,
|
|
struct probe_trace_arg_ref **ref_ptr,
|
|
Dwarf_Die *die_mem)
|
|
{
|
|
struct probe_trace_arg_ref *ref = *ref_ptr;
|
|
Dwarf_Die type;
|
|
Dwarf_Word offs;
|
|
int ret, tag;
|
|
|
|
pr_debug("converting %s in %s\n", field->name, varname);
|
|
if (die_get_real_type(vr_die, &type) == NULL) {
|
|
pr_warning("Failed to get the type of %s.\n", varname);
|
|
return -ENOENT;
|
|
}
|
|
pr_debug2("Var real type: (%x)\n", (unsigned)dwarf_dieoffset(&type));
|
|
tag = dwarf_tag(&type);
|
|
|
|
if (field->name[0] == '[' &&
|
|
(tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
|
|
if (field->next)
|
|
/* Save original type for next field */
|
|
memcpy(die_mem, &type, sizeof(*die_mem));
|
|
/* Get the type of this array */
|
|
if (die_get_real_type(&type, &type) == NULL) {
|
|
pr_warning("Failed to get the type of %s.\n", varname);
|
|
return -ENOENT;
|
|
}
|
|
pr_debug2("Array real type: (%x)\n",
|
|
(unsigned)dwarf_dieoffset(&type));
|
|
if (tag == DW_TAG_pointer_type) {
|
|
ref = zalloc(sizeof(struct probe_trace_arg_ref));
|
|
if (ref == NULL)
|
|
return -ENOMEM;
|
|
if (*ref_ptr)
|
|
(*ref_ptr)->next = ref;
|
|
else
|
|
*ref_ptr = ref;
|
|
}
|
|
ref->offset += dwarf_bytesize(&type) * field->index;
|
|
if (!field->next)
|
|
/* Save vr_die for converting types */
|
|
memcpy(die_mem, vr_die, sizeof(*die_mem));
|
|
goto next;
|
|
} else if (tag == DW_TAG_pointer_type) {
|
|
/* Check the pointer and dereference */
|
|
if (!field->ref) {
|
|
pr_err("Semantic error: %s must be referred by '->'\n",
|
|
field->name);
|
|
return -EINVAL;
|
|
}
|
|
/* Get the type pointed by this pointer */
|
|
if (die_get_real_type(&type, &type) == NULL) {
|
|
pr_warning("Failed to get the type of %s.\n", varname);
|
|
return -ENOENT;
|
|
}
|
|
/* Verify it is a data structure */
|
|
tag = dwarf_tag(&type);
|
|
if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
|
|
pr_warning("%s is not a data structure nor an union.\n",
|
|
varname);
|
|
return -EINVAL;
|
|
}
|
|
|
|
ref = zalloc(sizeof(struct probe_trace_arg_ref));
|
|
if (ref == NULL)
|
|
return -ENOMEM;
|
|
if (*ref_ptr)
|
|
(*ref_ptr)->next = ref;
|
|
else
|
|
*ref_ptr = ref;
|
|
} else {
|
|
/* Verify it is a data structure */
|
|
if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
|
|
pr_warning("%s is not a data structure nor an union.\n",
|
|
varname);
|
|
return -EINVAL;
|
|
}
|
|
if (field->name[0] == '[') {
|
|
pr_err("Semantic error: %s is not a pointor"
|
|
" nor array.\n", varname);
|
|
return -EINVAL;
|
|
}
|
|
if (field->ref) {
|
|
pr_err("Semantic error: %s must be referred by '.'\n",
|
|
field->name);
|
|
return -EINVAL;
|
|
}
|
|
if (!ref) {
|
|
pr_warning("Structure on a register is not "
|
|
"supported yet.\n");
|
|
return -ENOTSUP;
|
|
}
|
|
}
|
|
|
|
if (die_find_member(&type, field->name, die_mem) == NULL) {
|
|
pr_warning("%s(tyep:%s) has no member %s.\n", varname,
|
|
dwarf_diename(&type), field->name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Get the offset of the field */
|
|
if (tag == DW_TAG_union_type) {
|
|
offs = 0;
|
|
} else {
|
|
ret = die_get_data_member_location(die_mem, &offs);
|
|
if (ret < 0) {
|
|
pr_warning("Failed to get the offset of %s.\n",
|
|
field->name);
|
|
return ret;
|
|
}
|
|
}
|
|
ref->offset += (long)offs;
|
|
|
|
next:
|
|
/* Converting next field */
|
|
if (field->next)
|
|
return convert_variable_fields(die_mem, field->name,
|
|
field->next, &ref, die_mem);
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
/* Show a variables in kprobe event format */
|
|
static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
|
|
{
|
|
Dwarf_Die die_mem;
|
|
int ret;
|
|
|
|
pr_debug("Converting variable %s into trace event.\n",
|
|
dwarf_diename(vr_die));
|
|
|
|
ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
|
|
pf->tvar);
|
|
if (ret == -ENOENT)
|
|
pr_err("Failed to find the location of %s at this address.\n"
|
|
" Perhaps, it has been optimized out.\n", pf->pvar->var);
|
|
else if (ret == -ENOTSUP)
|
|
pr_err("Sorry, we don't support this variable location yet.\n");
|
|
else if (pf->pvar->field) {
|
|
ret = convert_variable_fields(vr_die, pf->pvar->var,
|
|
pf->pvar->field, &pf->tvar->ref,
|
|
&die_mem);
|
|
vr_die = &die_mem;
|
|
}
|
|
if (ret == 0)
|
|
ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type);
|
|
/* *expr will be cached in libdw. Don't free it. */
|
|
return ret;
|
|
}
|
|
|
|
/* Find a variable in a scope DIE */
|
|
static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
|
|
{
|
|
Dwarf_Die vr_die;
|
|
char buf[32], *ptr;
|
|
int ret = 0;
|
|
|
|
if (!is_c_varname(pf->pvar->var)) {
|
|
/* Copy raw parameters */
|
|
pf->tvar->value = strdup(pf->pvar->var);
|
|
if (pf->tvar->value == NULL)
|
|
return -ENOMEM;
|
|
if (pf->pvar->type) {
|
|
pf->tvar->type = strdup(pf->pvar->type);
|
|
if (pf->tvar->type == NULL)
|
|
return -ENOMEM;
|
|
}
|
|
if (pf->pvar->name) {
|
|
pf->tvar->name = strdup(pf->pvar->name);
|
|
if (pf->tvar->name == NULL)
|
|
return -ENOMEM;
|
|
} else
|
|
pf->tvar->name = NULL;
|
|
return 0;
|
|
}
|
|
|
|
if (pf->pvar->name)
|
|
pf->tvar->name = strdup(pf->pvar->name);
|
|
else {
|
|
ret = synthesize_perf_probe_arg(pf->pvar, buf, 32);
|
|
if (ret < 0)
|
|
return ret;
|
|
ptr = strchr(buf, ':'); /* Change type separator to _ */
|
|
if (ptr)
|
|
*ptr = '_';
|
|
pf->tvar->name = strdup(buf);
|
|
}
|
|
if (pf->tvar->name == NULL)
|
|
return -ENOMEM;
|
|
|
|
pr_debug("Searching '%s' variable in context.\n", pf->pvar->var);
|
|
/* Search child die for local variables and parameters. */
|
|
if (!die_find_variable_at(sc_die, pf->pvar->var, pf->addr, &vr_die)) {
|
|
/* Search again in global variables */
|
|
if (!die_find_variable_at(&pf->cu_die, pf->pvar->var, 0, &vr_die))
|
|
ret = -ENOENT;
|
|
}
|
|
if (ret >= 0)
|
|
ret = convert_variable(&vr_die, pf);
|
|
|
|
if (ret < 0)
|
|
pr_warning("Failed to find '%s' in this function.\n",
|
|
pf->pvar->var);
|
|
return ret;
|
|
}
|
|
|
|
/* Convert subprogram DIE to trace point */
|
|
static int convert_to_trace_point(Dwarf_Die *sp_die, Dwarf_Addr paddr,
|
|
bool retprobe, struct probe_trace_point *tp)
|
|
{
|
|
Dwarf_Addr eaddr, highaddr;
|
|
const char *name;
|
|
|
|
/* Copy the name of probe point */
|
|
name = dwarf_diename(sp_die);
|
|
if (name) {
|
|
if (dwarf_entrypc(sp_die, &eaddr) != 0) {
|
|
pr_warning("Failed to get entry address of %s\n",
|
|
dwarf_diename(sp_die));
|
|
return -ENOENT;
|
|
}
|
|
if (dwarf_highpc(sp_die, &highaddr) != 0) {
|
|
pr_warning("Failed to get end address of %s\n",
|
|
dwarf_diename(sp_die));
|
|
return -ENOENT;
|
|
}
|
|
if (paddr > highaddr) {
|
|
pr_warning("Offset specified is greater than size of %s\n",
|
|
dwarf_diename(sp_die));
|
|
return -EINVAL;
|
|
}
|
|
tp->symbol = strdup(name);
|
|
if (tp->symbol == NULL)
|
|
return -ENOMEM;
|
|
tp->offset = (unsigned long)(paddr - eaddr);
|
|
} else
|
|
/* This function has no name. */
|
|
tp->offset = (unsigned long)paddr;
|
|
|
|
/* Return probe must be on the head of a subprogram */
|
|
if (retprobe) {
|
|
if (eaddr != paddr) {
|
|
pr_warning("Return probe must be on the head of"
|
|
" a real function.\n");
|
|
return -EINVAL;
|
|
}
|
|
tp->retprobe = true;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Call probe_finder callback with scope DIE */
|
|
static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf)
|
|
{
|
|
Dwarf_Attribute fb_attr;
|
|
size_t nops;
|
|
int ret;
|
|
|
|
if (!sc_die) {
|
|
pr_err("Caller must pass a scope DIE. Program error.\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* If not a real subprogram, find a real one */
|
|
if (dwarf_tag(sc_die) != DW_TAG_subprogram) {
|
|
if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
|
|
pr_warning("Failed to find probe point in any "
|
|
"functions.\n");
|
|
return -ENOENT;
|
|
}
|
|
} else
|
|
memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die));
|
|
|
|
/* Get the frame base attribute/ops from subprogram */
|
|
dwarf_attr(&pf->sp_die, DW_AT_frame_base, &fb_attr);
|
|
ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
|
|
if (ret <= 0 || nops == 0) {
|
|
pf->fb_ops = NULL;
|
|
#if _ELFUTILS_PREREQ(0, 142)
|
|
} else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
|
|
pf->cfi != NULL) {
|
|
Dwarf_Frame *frame;
|
|
if (dwarf_cfi_addrframe(pf->cfi, pf->addr, &frame) != 0 ||
|
|
dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
|
|
pr_warning("Failed to get call frame on 0x%jx\n",
|
|
(uintmax_t)pf->addr);
|
|
return -ENOENT;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/* Call finder's callback handler */
|
|
ret = pf->callback(sc_die, pf);
|
|
|
|
/* *pf->fb_ops will be cached in libdw. Don't free it. */
|
|
pf->fb_ops = NULL;
|
|
|
|
return ret;
|
|
}
|
|
|
|
struct find_scope_param {
|
|
const char *function;
|
|
const char *file;
|
|
int line;
|
|
int diff;
|
|
Dwarf_Die *die_mem;
|
|
bool found;
|
|
};
|
|
|
|
static int find_best_scope_cb(Dwarf_Die *fn_die, void *data)
|
|
{
|
|
struct find_scope_param *fsp = data;
|
|
const char *file;
|
|
int lno;
|
|
|
|
/* Skip if declared file name does not match */
|
|
if (fsp->file) {
|
|
file = dwarf_decl_file(fn_die);
|
|
if (!file || strcmp(fsp->file, file) != 0)
|
|
return 0;
|
|
}
|
|
/* If the function name is given, that's what user expects */
|
|
if (fsp->function) {
|
|
if (die_compare_name(fn_die, fsp->function)) {
|
|
memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
|
|
fsp->found = true;
|
|
return 1;
|
|
}
|
|
} else {
|
|
/* With the line number, find the nearest declared DIE */
|
|
dwarf_decl_line(fn_die, &lno);
|
|
if (lno < fsp->line && fsp->diff > fsp->line - lno) {
|
|
/* Keep a candidate and continue */
|
|
fsp->diff = fsp->line - lno;
|
|
memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
|
|
fsp->found = true;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Find an appropriate scope fits to given conditions */
|
|
static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem)
|
|
{
|
|
struct find_scope_param fsp = {
|
|
.function = pf->pev->point.function,
|
|
.file = pf->fname,
|
|
.line = pf->lno,
|
|
.diff = INT_MAX,
|
|
.die_mem = die_mem,
|
|
.found = false,
|
|
};
|
|
|
|
cu_walk_functions_at(&pf->cu_die, pf->addr, find_best_scope_cb, &fsp);
|
|
|
|
return fsp.found ? die_mem : NULL;
|
|
}
|
|
|
|
static int probe_point_line_walker(const char *fname, int lineno,
|
|
Dwarf_Addr addr, void *data)
|
|
{
|
|
struct probe_finder *pf = data;
|
|
Dwarf_Die *sc_die, die_mem;
|
|
int ret;
|
|
|
|
if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
|
|
return 0;
|
|
|
|
pf->addr = addr;
|
|
sc_die = find_best_scope(pf, &die_mem);
|
|
if (!sc_die) {
|
|
pr_warning("Failed to find scope of probe point.\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
ret = call_probe_finder(sc_die, pf);
|
|
|
|
/* Continue if no error, because the line will be in inline function */
|
|
return ret < 0 ? ret : 0;
|
|
}
|
|
|
|
/* Find probe point from its line number */
|
|
static int find_probe_point_by_line(struct probe_finder *pf)
|
|
{
|
|
return die_walk_lines(&pf->cu_die, probe_point_line_walker, pf);
|
|
}
|
|
|
|
/* Find lines which match lazy pattern */
|
|
static int find_lazy_match_lines(struct list_head *head,
|
|
const char *fname, const char *pat)
|
|
{
|
|
FILE *fp;
|
|
char *line = NULL;
|
|
size_t line_len;
|
|
ssize_t len;
|
|
int count = 0, linenum = 1;
|
|
|
|
fp = fopen(fname, "r");
|
|
if (!fp) {
|
|
pr_warning("Failed to open %s: %s\n", fname, strerror(errno));
|
|
return -errno;
|
|
}
|
|
|
|
while ((len = getline(&line, &line_len, fp)) > 0) {
|
|
|
|
if (line[len - 1] == '\n')
|
|
line[len - 1] = '\0';
|
|
|
|
if (strlazymatch(line, pat)) {
|
|
line_list__add_line(head, linenum);
|
|
count++;
|
|
}
|
|
linenum++;
|
|
}
|
|
|
|
if (ferror(fp))
|
|
count = -errno;
|
|
free(line);
|
|
fclose(fp);
|
|
|
|
if (count == 0)
|
|
pr_debug("No matched lines found in %s.\n", fname);
|
|
return count;
|
|
}
|
|
|
|
static int probe_point_lazy_walker(const char *fname, int lineno,
|
|
Dwarf_Addr addr, void *data)
|
|
{
|
|
struct probe_finder *pf = data;
|
|
Dwarf_Die *sc_die, die_mem;
|
|
int ret;
|
|
|
|
if (!line_list__has_line(&pf->lcache, lineno) ||
|
|
strtailcmp(fname, pf->fname) != 0)
|
|
return 0;
|
|
|
|
pr_debug("Probe line found: line:%d addr:0x%llx\n",
|
|
lineno, (unsigned long long)addr);
|
|
pf->addr = addr;
|
|
pf->lno = lineno;
|
|
sc_die = find_best_scope(pf, &die_mem);
|
|
if (!sc_die) {
|
|
pr_warning("Failed to find scope of probe point.\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
ret = call_probe_finder(sc_die, pf);
|
|
|
|
/*
|
|
* Continue if no error, because the lazy pattern will match
|
|
* to other lines
|
|
*/
|
|
return ret < 0 ? ret : 0;
|
|
}
|
|
|
|
/* Find probe points from lazy pattern */
|
|
static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (list_empty(&pf->lcache)) {
|
|
/* Matching lazy line pattern */
|
|
ret = find_lazy_match_lines(&pf->lcache, pf->fname,
|
|
pf->pev->point.lazy_line);
|
|
if (ret <= 0)
|
|
return ret;
|
|
}
|
|
|
|
return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
|
|
}
|
|
|
|
static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
|
|
{
|
|
struct probe_finder *pf = data;
|
|
struct perf_probe_point *pp = &pf->pev->point;
|
|
Dwarf_Addr addr;
|
|
int ret;
|
|
|
|
if (pp->lazy_line)
|
|
ret = find_probe_point_lazy(in_die, pf);
|
|
else {
|
|
/* Get probe address */
|
|
if (dwarf_entrypc(in_die, &addr) != 0) {
|
|
pr_warning("Failed to get entry address of %s.\n",
|
|
dwarf_diename(in_die));
|
|
return -ENOENT;
|
|
}
|
|
pf->addr = addr;
|
|
pf->addr += pp->offset;
|
|
pr_debug("found inline addr: 0x%jx\n",
|
|
(uintmax_t)pf->addr);
|
|
|
|
ret = call_probe_finder(in_die, pf);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Callback parameter with return value for libdw */
|
|
struct dwarf_callback_param {
|
|
void *data;
|
|
int retval;
|
|
};
|
|
|
|
/* Search function from function name */
|
|
static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
|
|
{
|
|
struct dwarf_callback_param *param = data;
|
|
struct probe_finder *pf = param->data;
|
|
struct perf_probe_point *pp = &pf->pev->point;
|
|
Dwarf_Attribute attr;
|
|
|
|
/* Check tag and diename */
|
|
if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
|
|
!die_compare_name(sp_die, pp->function) ||
|
|
dwarf_attr(sp_die, DW_AT_declaration, &attr))
|
|
return DWARF_CB_OK;
|
|
|
|
/* Check declared file */
|
|
if (pp->file && strtailcmp(pp->file, dwarf_decl_file(sp_die)))
|
|
return DWARF_CB_OK;
|
|
|
|
pf->fname = dwarf_decl_file(sp_die);
|
|
if (pp->line) { /* Function relative line */
|
|
dwarf_decl_line(sp_die, &pf->lno);
|
|
pf->lno += pp->line;
|
|
param->retval = find_probe_point_by_line(pf);
|
|
} else if (!dwarf_func_inline(sp_die)) {
|
|
/* Real function */
|
|
if (pp->lazy_line)
|
|
param->retval = find_probe_point_lazy(sp_die, pf);
|
|
else {
|
|
if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
|
|
pr_warning("Failed to get entry address of "
|
|
"%s.\n", dwarf_diename(sp_die));
|
|
param->retval = -ENOENT;
|
|
return DWARF_CB_ABORT;
|
|
}
|
|
pf->addr += pp->offset;
|
|
/* TODO: Check the address in this function */
|
|
param->retval = call_probe_finder(sp_die, pf);
|
|
}
|
|
} else
|
|
/* Inlined function: search instances */
|
|
param->retval = die_walk_instances(sp_die,
|
|
probe_point_inline_cb, (void *)pf);
|
|
|
|
return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
|
|
}
|
|
|
|
static int find_probe_point_by_func(struct probe_finder *pf)
|
|
{
|
|
struct dwarf_callback_param _param = {.data = (void *)pf,
|
|
.retval = 0};
|
|
dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
|
|
return _param.retval;
|
|
}
|
|
|
|
struct pubname_callback_param {
|
|
char *function;
|
|
char *file;
|
|
Dwarf_Die *cu_die;
|
|
Dwarf_Die *sp_die;
|
|
int found;
|
|
};
|
|
|
|
static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
|
|
{
|
|
struct pubname_callback_param *param = data;
|
|
|
|
if (dwarf_offdie(dbg, gl->die_offset, param->sp_die)) {
|
|
if (dwarf_tag(param->sp_die) != DW_TAG_subprogram)
|
|
return DWARF_CB_OK;
|
|
|
|
if (die_compare_name(param->sp_die, param->function)) {
|
|
if (!dwarf_offdie(dbg, gl->cu_offset, param->cu_die))
|
|
return DWARF_CB_OK;
|
|
|
|
if (param->file &&
|
|
strtailcmp(param->file, dwarf_decl_file(param->sp_die)))
|
|
return DWARF_CB_OK;
|
|
|
|
param->found = 1;
|
|
return DWARF_CB_ABORT;
|
|
}
|
|
}
|
|
|
|
return DWARF_CB_OK;
|
|
}
|
|
|
|
/* Find probe points from debuginfo */
|
|
static int debuginfo__find_probes(struct debuginfo *self,
|
|
struct probe_finder *pf)
|
|
{
|
|
struct perf_probe_point *pp = &pf->pev->point;
|
|
Dwarf_Off off, noff;
|
|
size_t cuhl;
|
|
Dwarf_Die *diep;
|
|
int ret = 0;
|
|
|
|
#if _ELFUTILS_PREREQ(0, 142)
|
|
/* Get the call frame information from this dwarf */
|
|
pf->cfi = dwarf_getcfi(self->dbg);
|
|
#endif
|
|
|
|
off = 0;
|
|
line_list__init(&pf->lcache);
|
|
|
|
/* Fastpath: lookup by function name from .debug_pubnames section */
|
|
if (pp->function) {
|
|
struct pubname_callback_param pubname_param = {
|
|
.function = pp->function,
|
|
.file = pp->file,
|
|
.cu_die = &pf->cu_die,
|
|
.sp_die = &pf->sp_die,
|
|
.found = 0,
|
|
};
|
|
struct dwarf_callback_param probe_param = {
|
|
.data = pf,
|
|
};
|
|
|
|
dwarf_getpubnames(self->dbg, pubname_search_cb,
|
|
&pubname_param, 0);
|
|
if (pubname_param.found) {
|
|
ret = probe_point_search_cb(&pf->sp_die, &probe_param);
|
|
if (ret)
|
|
goto found;
|
|
}
|
|
}
|
|
|
|
/* Loop on CUs (Compilation Unit) */
|
|
while (!dwarf_nextcu(self->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
|
|
/* Get the DIE(Debugging Information Entry) of this CU */
|
|
diep = dwarf_offdie(self->dbg, off + cuhl, &pf->cu_die);
|
|
if (!diep)
|
|
continue;
|
|
|
|
/* Check if target file is included. */
|
|
if (pp->file)
|
|
pf->fname = cu_find_realpath(&pf->cu_die, pp->file);
|
|
else
|
|
pf->fname = NULL;
|
|
|
|
if (!pp->file || pf->fname) {
|
|
if (pp->function)
|
|
ret = find_probe_point_by_func(pf);
|
|
else if (pp->lazy_line)
|
|
ret = find_probe_point_lazy(NULL, pf);
|
|
else {
|
|
pf->lno = pp->line;
|
|
ret = find_probe_point_by_line(pf);
|
|
}
|
|
if (ret < 0)
|
|
break;
|
|
}
|
|
off = noff;
|
|
}
|
|
|
|
found:
|
|
line_list__free(&pf->lcache);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Add a found probe point into trace event list */
|
|
static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
|
|
{
|
|
struct trace_event_finder *tf =
|
|
container_of(pf, struct trace_event_finder, pf);
|
|
struct probe_trace_event *tev;
|
|
int ret, i;
|
|
|
|
/* Check number of tevs */
|
|
if (tf->ntevs == tf->max_tevs) {
|
|
pr_warning("Too many( > %d) probe point found.\n",
|
|
tf->max_tevs);
|
|
return -ERANGE;
|
|
}
|
|
tev = &tf->tevs[tf->ntevs++];
|
|
|
|
/* Trace point should be converted from subprogram DIE */
|
|
ret = convert_to_trace_point(&pf->sp_die, pf->addr,
|
|
pf->pev->point.retprobe, &tev->point);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
|
|
tev->point.offset);
|
|
|
|
/* Find each argument */
|
|
tev->nargs = pf->pev->nargs;
|
|
tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
|
|
if (tev->args == NULL)
|
|
return -ENOMEM;
|
|
for (i = 0; i < pf->pev->nargs; i++) {
|
|
pf->pvar = &pf->pev->args[i];
|
|
pf->tvar = &tev->args[i];
|
|
/* Variable should be found from scope DIE */
|
|
ret = find_variable(sc_die, pf);
|
|
if (ret != 0)
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Find probe_trace_events specified by perf_probe_event from debuginfo */
|
|
int debuginfo__find_trace_events(struct debuginfo *self,
|
|
struct perf_probe_event *pev,
|
|
struct probe_trace_event **tevs, int max_tevs)
|
|
{
|
|
struct trace_event_finder tf = {
|
|
.pf = {.pev = pev, .callback = add_probe_trace_event},
|
|
.max_tevs = max_tevs};
|
|
int ret;
|
|
|
|
/* Allocate result tevs array */
|
|
*tevs = zalloc(sizeof(struct probe_trace_event) * max_tevs);
|
|
if (*tevs == NULL)
|
|
return -ENOMEM;
|
|
|
|
tf.tevs = *tevs;
|
|
tf.ntevs = 0;
|
|
|
|
ret = debuginfo__find_probes(self, &tf.pf);
|
|
if (ret < 0) {
|
|
free(*tevs);
|
|
*tevs = NULL;
|
|
return ret;
|
|
}
|
|
|
|
return (ret < 0) ? ret : tf.ntevs;
|
|
}
|
|
|
|
#define MAX_VAR_LEN 64
|
|
|
|
/* Collect available variables in this scope */
|
|
static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
|
|
{
|
|
struct available_var_finder *af = data;
|
|
struct variable_list *vl;
|
|
char buf[MAX_VAR_LEN];
|
|
int tag, ret;
|
|
|
|
vl = &af->vls[af->nvls - 1];
|
|
|
|
tag = dwarf_tag(die_mem);
|
|
if (tag == DW_TAG_formal_parameter ||
|
|
tag == DW_TAG_variable) {
|
|
ret = convert_variable_location(die_mem, af->pf.addr,
|
|
af->pf.fb_ops, NULL);
|
|
if (ret == 0) {
|
|
ret = die_get_varname(die_mem, buf, MAX_VAR_LEN);
|
|
pr_debug2("Add new var: %s\n", buf);
|
|
if (ret > 0)
|
|
strlist__add(vl->vars, buf);
|
|
}
|
|
}
|
|
|
|
if (af->child && dwarf_haspc(die_mem, af->pf.addr))
|
|
return DIE_FIND_CB_CONTINUE;
|
|
else
|
|
return DIE_FIND_CB_SIBLING;
|
|
}
|
|
|
|
/* Add a found vars into available variables list */
|
|
static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
|
|
{
|
|
struct available_var_finder *af =
|
|
container_of(pf, struct available_var_finder, pf);
|
|
struct variable_list *vl;
|
|
Dwarf_Die die_mem;
|
|
int ret;
|
|
|
|
/* Check number of tevs */
|
|
if (af->nvls == af->max_vls) {
|
|
pr_warning("Too many( > %d) probe point found.\n", af->max_vls);
|
|
return -ERANGE;
|
|
}
|
|
vl = &af->vls[af->nvls++];
|
|
|
|
/* Trace point should be converted from subprogram DIE */
|
|
ret = convert_to_trace_point(&pf->sp_die, pf->addr,
|
|
pf->pev->point.retprobe, &vl->point);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
pr_debug("Probe point found: %s+%lu\n", vl->point.symbol,
|
|
vl->point.offset);
|
|
|
|
/* Find local variables */
|
|
vl->vars = strlist__new(true, NULL);
|
|
if (vl->vars == NULL)
|
|
return -ENOMEM;
|
|
af->child = true;
|
|
die_find_child(sc_die, collect_variables_cb, (void *)af, &die_mem);
|
|
|
|
/* Find external variables */
|
|
if (!af->externs)
|
|
goto out;
|
|
/* Don't need to search child DIE for externs. */
|
|
af->child = false;
|
|
die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem);
|
|
|
|
out:
|
|
if (strlist__empty(vl->vars)) {
|
|
strlist__delete(vl->vars);
|
|
vl->vars = NULL;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Find available variables at given probe point */
|
|
int debuginfo__find_available_vars_at(struct debuginfo *self,
|
|
struct perf_probe_event *pev,
|
|
struct variable_list **vls,
|
|
int max_vls, bool externs)
|
|
{
|
|
struct available_var_finder af = {
|
|
.pf = {.pev = pev, .callback = add_available_vars},
|
|
.max_vls = max_vls, .externs = externs};
|
|
int ret;
|
|
|
|
/* Allocate result vls array */
|
|
*vls = zalloc(sizeof(struct variable_list) * max_vls);
|
|
if (*vls == NULL)
|
|
return -ENOMEM;
|
|
|
|
af.vls = *vls;
|
|
af.nvls = 0;
|
|
|
|
ret = debuginfo__find_probes(self, &af.pf);
|
|
if (ret < 0) {
|
|
/* Free vlist for error */
|
|
while (af.nvls--) {
|
|
if (af.vls[af.nvls].point.symbol)
|
|
free(af.vls[af.nvls].point.symbol);
|
|
if (af.vls[af.nvls].vars)
|
|
strlist__delete(af.vls[af.nvls].vars);
|
|
}
|
|
free(af.vls);
|
|
*vls = NULL;
|
|
return ret;
|
|
}
|
|
|
|
return (ret < 0) ? ret : af.nvls;
|
|
}
|
|
|
|
/* Reverse search */
|
|
int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
|
|
struct perf_probe_point *ppt)
|
|
{
|
|
Dwarf_Die cudie, spdie, indie;
|
|
Dwarf_Addr _addr, baseaddr;
|
|
const char *fname = NULL, *func = NULL, *tmp;
|
|
int baseline = 0, lineno = 0, ret = 0;
|
|
|
|
/* Adjust address with bias */
|
|
addr += self->bias;
|
|
|
|
/* Find cu die */
|
|
if (!dwarf_addrdie(self->dbg, (Dwarf_Addr)addr - self->bias, &cudie)) {
|
|
pr_warning("Failed to find debug information for address %lx\n",
|
|
addr);
|
|
ret = -EINVAL;
|
|
goto end;
|
|
}
|
|
|
|
/* Find a corresponding line (filename and lineno) */
|
|
cu_find_lineinfo(&cudie, addr, &fname, &lineno);
|
|
/* Don't care whether it failed or not */
|
|
|
|
/* Find a corresponding function (name, baseline and baseaddr) */
|
|
if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
|
|
/* Get function entry information */
|
|
tmp = dwarf_diename(&spdie);
|
|
if (!tmp ||
|
|
dwarf_entrypc(&spdie, &baseaddr) != 0 ||
|
|
dwarf_decl_line(&spdie, &baseline) != 0)
|
|
goto post;
|
|
func = tmp;
|
|
|
|
if (addr == (unsigned long)baseaddr)
|
|
/* Function entry - Relative line number is 0 */
|
|
lineno = baseline;
|
|
else if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
|
|
&indie)) {
|
|
if (dwarf_entrypc(&indie, &_addr) == 0 &&
|
|
_addr == addr)
|
|
/*
|
|
* addr is at an inline function entry.
|
|
* In this case, lineno should be the call-site
|
|
* line number.
|
|
*/
|
|
lineno = die_get_call_lineno(&indie);
|
|
else {
|
|
/*
|
|
* addr is in an inline function body.
|
|
* Since lineno points one of the lines
|
|
* of the inline function, baseline should
|
|
* be the entry line of the inline function.
|
|
*/
|
|
tmp = dwarf_diename(&indie);
|
|
if (tmp &&
|
|
dwarf_decl_line(&spdie, &baseline) == 0)
|
|
func = tmp;
|
|
}
|
|
}
|
|
}
|
|
|
|
post:
|
|
/* Make a relative line number or an offset */
|
|
if (lineno)
|
|
ppt->line = lineno - baseline;
|
|
else if (func)
|
|
ppt->offset = addr - (unsigned long)baseaddr;
|
|
|
|
/* Duplicate strings */
|
|
if (func) {
|
|
ppt->function = strdup(func);
|
|
if (ppt->function == NULL) {
|
|
ret = -ENOMEM;
|
|
goto end;
|
|
}
|
|
}
|
|
if (fname) {
|
|
ppt->file = strdup(fname);
|
|
if (ppt->file == NULL) {
|
|
if (ppt->function) {
|
|
free(ppt->function);
|
|
ppt->function = NULL;
|
|
}
|
|
ret = -ENOMEM;
|
|
goto end;
|
|
}
|
|
}
|
|
end:
|
|
if (ret == 0 && (fname || func))
|
|
ret = 1; /* Found a point */
|
|
return ret;
|
|
}
|
|
|
|
/* Add a line and store the src path */
|
|
static int line_range_add_line(const char *src, unsigned int lineno,
|
|
struct line_range *lr)
|
|
{
|
|
/* Copy source path */
|
|
if (!lr->path) {
|
|
lr->path = strdup(src);
|
|
if (lr->path == NULL)
|
|
return -ENOMEM;
|
|
}
|
|
return line_list__add_line(&lr->line_list, lineno);
|
|
}
|
|
|
|
static int line_range_walk_cb(const char *fname, int lineno,
|
|
Dwarf_Addr addr __maybe_unused,
|
|
void *data)
|
|
{
|
|
struct line_finder *lf = data;
|
|
|
|
if ((strtailcmp(fname, lf->fname) != 0) ||
|
|
(lf->lno_s > lineno || lf->lno_e < lineno))
|
|
return 0;
|
|
|
|
if (line_range_add_line(fname, lineno, lf->lr) < 0)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Find line range from its line number */
|
|
static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
|
|
{
|
|
int ret;
|
|
|
|
ret = die_walk_lines(sp_die ?: &lf->cu_die, line_range_walk_cb, lf);
|
|
|
|
/* Update status */
|
|
if (ret >= 0)
|
|
if (!list_empty(&lf->lr->line_list))
|
|
ret = lf->found = 1;
|
|
else
|
|
ret = 0; /* Lines are not found */
|
|
else {
|
|
free(lf->lr->path);
|
|
lf->lr->path = NULL;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
|
|
{
|
|
find_line_range_by_line(in_die, data);
|
|
|
|
/*
|
|
* We have to check all instances of inlined function, because
|
|
* some execution paths can be optimized out depends on the
|
|
* function argument of instances
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
/* Search function from function name */
|
|
static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
|
|
{
|
|
struct dwarf_callback_param *param = data;
|
|
struct line_finder *lf = param->data;
|
|
struct line_range *lr = lf->lr;
|
|
|
|
/* Check declared file */
|
|
if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))
|
|
return DWARF_CB_OK;
|
|
|
|
if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
|
|
die_compare_name(sp_die, lr->function)) {
|
|
lf->fname = dwarf_decl_file(sp_die);
|
|
dwarf_decl_line(sp_die, &lr->offset);
|
|
pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
|
|
lf->lno_s = lr->offset + lr->start;
|
|
if (lf->lno_s < 0) /* Overflow */
|
|
lf->lno_s = INT_MAX;
|
|
lf->lno_e = lr->offset + lr->end;
|
|
if (lf->lno_e < 0) /* Overflow */
|
|
lf->lno_e = INT_MAX;
|
|
pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
|
|
lr->start = lf->lno_s;
|
|
lr->end = lf->lno_e;
|
|
if (dwarf_func_inline(sp_die))
|
|
param->retval = die_walk_instances(sp_die,
|
|
line_range_inline_cb, lf);
|
|
else
|
|
param->retval = find_line_range_by_line(sp_die, lf);
|
|
return DWARF_CB_ABORT;
|
|
}
|
|
return DWARF_CB_OK;
|
|
}
|
|
|
|
static int find_line_range_by_func(struct line_finder *lf)
|
|
{
|
|
struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
|
|
dwarf_getfuncs(&lf->cu_die, line_range_search_cb, ¶m, 0);
|
|
return param.retval;
|
|
}
|
|
|
|
int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
|
|
{
|
|
struct line_finder lf = {.lr = lr, .found = 0};
|
|
int ret = 0;
|
|
Dwarf_Off off = 0, noff;
|
|
size_t cuhl;
|
|
Dwarf_Die *diep;
|
|
const char *comp_dir;
|
|
|
|
/* Fastpath: lookup by function name from .debug_pubnames section */
|
|
if (lr->function) {
|
|
struct pubname_callback_param pubname_param = {
|
|
.function = lr->function, .file = lr->file,
|
|
.cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
|
|
struct dwarf_callback_param line_range_param = {
|
|
.data = (void *)&lf, .retval = 0};
|
|
|
|
dwarf_getpubnames(self->dbg, pubname_search_cb,
|
|
&pubname_param, 0);
|
|
if (pubname_param.found) {
|
|
line_range_search_cb(&lf.sp_die, &line_range_param);
|
|
if (lf.found)
|
|
goto found;
|
|
}
|
|
}
|
|
|
|
/* Loop on CUs (Compilation Unit) */
|
|
while (!lf.found && ret >= 0) {
|
|
if (dwarf_nextcu(self->dbg, off, &noff, &cuhl,
|
|
NULL, NULL, NULL) != 0)
|
|
break;
|
|
|
|
/* Get the DIE(Debugging Information Entry) of this CU */
|
|
diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die);
|
|
if (!diep)
|
|
continue;
|
|
|
|
/* Check if target file is included. */
|
|
if (lr->file)
|
|
lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
|
|
else
|
|
lf.fname = 0;
|
|
|
|
if (!lr->file || lf.fname) {
|
|
if (lr->function)
|
|
ret = find_line_range_by_func(&lf);
|
|
else {
|
|
lf.lno_s = lr->start;
|
|
lf.lno_e = lr->end;
|
|
ret = find_line_range_by_line(NULL, &lf);
|
|
}
|
|
}
|
|
off = noff;
|
|
}
|
|
|
|
found:
|
|
/* Store comp_dir */
|
|
if (lf.found) {
|
|
comp_dir = cu_get_comp_dir(&lf.cu_die);
|
|
if (comp_dir) {
|
|
lr->comp_dir = strdup(comp_dir);
|
|
if (!lr->comp_dir)
|
|
ret = -ENOMEM;
|
|
}
|
|
}
|
|
|
|
pr_debug("path: %s\n", lr->path);
|
|
return (ret < 0) ? ret : lf.found;
|
|
}
|
|
|