diff options
Diffstat (limited to 'tools/perf/util/probe-finder.c')
-rw-r--r-- | tools/perf/util/probe-finder.c | 981 |
1 files changed, 243 insertions, 738 deletions
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 3b9d0b800d5c..5d732621a462 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -43,21 +43,6 @@ /* Kprobe tracer basic type is up to u64 */ #define MAX_BASIC_TYPE_BITS 64 -/* - * Compare the tail of two strings. - * Return 0 if whole of either string is same as another's tail part. - */ -static int strtailcmp(const char *s1, const char *s2) -{ - int i1 = strlen(s1); - int i2 = strlen(s2); - while (--i1 >= 0 && --i2 >= 0) { - if (s1[i1] != s2[i2]) - return s1[i1] - s2[i2]; - } - return 0; -} - /* Line number list operations */ /* Add a line to line number list */ @@ -131,29 +116,37 @@ static const Dwfl_Callbacks offline_callbacks = { }; /* Get a Dwarf from offline image */ -static Dwarf *dwfl_init_offline_dwarf(int fd, Dwfl **dwflp, Dwarf_Addr *bias) +static int debuginfo__init_offline_dwarf(struct debuginfo *self, + const char *path) { Dwfl_Module *mod; - Dwarf *dbg = NULL; + int fd; - if (!dwflp) - return NULL; + fd = open(path, O_RDONLY); + if (fd < 0) + return fd; - *dwflp = dwfl_begin(&offline_callbacks); - if (!*dwflp) - return NULL; + self->dwfl = dwfl_begin(&offline_callbacks); + if (!self->dwfl) + goto error; - mod = dwfl_report_offline(*dwflp, "", "", fd); + mod = dwfl_report_offline(self->dwfl, "", "", fd); if (!mod) goto error; - dbg = dwfl_module_getdwarf(mod, bias); - if (!dbg) { + self->dbg = dwfl_module_getdwarf(mod, &self->bias); + if (!self->dbg) + goto error; + + return 0; error: - dwfl_end(*dwflp); - *dwflp = NULL; - } - return dbg; + if (self->dwfl) + dwfl_end(self->dwfl); + else + close(fd); + memset(self, 0, sizeof(*self)); + + return -ENOENT; } #if _ELFUTILS_PREREQ(0, 148) @@ -189,597 +182,81 @@ static const Dwfl_Callbacks kernel_callbacks = { }; /* Get a Dwarf from live kernel image */ -static Dwarf *dwfl_init_live_kernel_dwarf(Dwarf_Addr addr, Dwfl **dwflp, - Dwarf_Addr *bias) +static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self, + Dwarf_Addr addr) { - Dwarf *dbg; - - if (!dwflp) - return NULL; - - *dwflp = dwfl_begin(&kernel_callbacks); - if (!*dwflp) - return NULL; + self->dwfl = dwfl_begin(&kernel_callbacks); + if (!self->dwfl) + return -EINVAL; /* Load the kernel dwarves: Don't care the result here */ - dwfl_linux_kernel_report_kernel(*dwflp); - dwfl_linux_kernel_report_modules(*dwflp); + dwfl_linux_kernel_report_kernel(self->dwfl); + dwfl_linux_kernel_report_modules(self->dwfl); - dbg = dwfl_addrdwarf(*dwflp, addr, bias); + self->dbg = dwfl_addrdwarf(self->dwfl, addr, &self->bias); /* Here, check whether we could get a real dwarf */ - if (!dbg) { + if (!self->dbg) { pr_debug("Failed to find kernel dwarf at %lx\n", (unsigned long)addr); - dwfl_end(*dwflp); - *dwflp = NULL; + dwfl_end(self->dwfl); + memset(self, 0, sizeof(*self)); + return -ENOENT; } - return dbg; + + return 0; } #else /* With older elfutils, this just support kernel module... */ -static Dwarf *dwfl_init_live_kernel_dwarf(Dwarf_Addr addr __used, Dwfl **dwflp, - Dwarf_Addr *bias) +static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self, + Dwarf_Addr addr __used) { - int fd; const char *path = kernel_get_module_path("kernel"); if (!path) { pr_err("Failed to find vmlinux path\n"); - return NULL; + return -ENOENT; } pr_debug2("Use file %s for debuginfo\n", path); - fd = open(path, O_RDONLY); - if (fd < 0) - return NULL; - - return dwfl_init_offline_dwarf(fd, dwflp, bias); + return debuginfo__init_offline_dwarf(self, path); } #endif -/* Dwarf wrappers */ - -/* Find the realpath of the target file. */ -static const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname) +struct debuginfo *debuginfo__new(const char *path) { - Dwarf_Files *files; - size_t nfiles, i; - const char *src = NULL; - int ret; - - if (!fname) + struct debuginfo *self = zalloc(sizeof(struct debuginfo)); + if (!self) return NULL; - ret = dwarf_getsrcfiles(cu_die, &files, &nfiles); - if (ret != 0) - return NULL; - - for (i = 0; i < nfiles; i++) { - src = dwarf_filesrc(files, i, NULL, NULL); - if (strtailcmp(src, fname) == 0) - break; + if (debuginfo__init_offline_dwarf(self, path) < 0) { + free(self); + self = NULL; } - if (i == nfiles) - return NULL; - return src; -} -/* Get DW_AT_comp_dir (should be NULL with older gcc) */ -static const char *cu_get_comp_dir(Dwarf_Die *cu_die) -{ - Dwarf_Attribute attr; - if (dwarf_attr(cu_die, DW_AT_comp_dir, &attr) == NULL) - return NULL; - return dwarf_formstring(&attr); + return self; } -/* Get a line number and file name for given address */ -static int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr, - const char **fname, int *lineno) +struct debuginfo *debuginfo__new_online_kernel(unsigned long addr) { - Dwarf_Line *line; - Dwarf_Addr laddr; - - line = dwarf_getsrc_die(cudie, (Dwarf_Addr)addr); - if (line && dwarf_lineaddr(line, &laddr) == 0 && - addr == (unsigned long)laddr && dwarf_lineno(line, lineno) == 0) { - *fname = dwarf_linesrc(line, NULL, NULL); - if (!*fname) - /* line number is useless without filename */ - *lineno = 0; - } - - return *lineno ?: -ENOENT; -} - -/* Compare diename and tname */ -static bool die_compare_name(Dwarf_Die *dw_die, const char *tname) -{ - const char *name; - name = dwarf_diename(dw_die); - return name ? (strcmp(tname, name) == 0) : false; -} - -/* Get callsite line number of inline-function instance */ -static int die_get_call_lineno(Dwarf_Die *in_die) -{ - Dwarf_Attribute attr; - Dwarf_Word ret; - - if (!dwarf_attr(in_die, DW_AT_call_line, &attr)) - return -ENOENT; - - dwarf_formudata(&attr, &ret); - return (int)ret; -} - -/* Get type die */ -static Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem) -{ - Dwarf_Attribute attr; - - if (dwarf_attr_integrate(vr_die, DW_AT_type, &attr) && - dwarf_formref_die(&attr, die_mem)) - return die_mem; - else + struct debuginfo *self = zalloc(sizeof(struct debuginfo)); + if (!self) return NULL; -} - -/* Get a type die, but skip qualifiers */ -static Dwarf_Die *__die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem) -{ - int tag; - - do { - vr_die = die_get_type(vr_die, die_mem); - if (!vr_die) - break; - tag = dwarf_tag(vr_die); - } while (tag == DW_TAG_const_type || - tag == DW_TAG_restrict_type || - tag == DW_TAG_volatile_type || - tag == DW_TAG_shared_type); - - return vr_die; -} - -/* Get a type die, but skip qualifiers and typedef */ -static Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem) -{ - do { - vr_die = __die_get_real_type(vr_die, die_mem); - } while (vr_die && dwarf_tag(vr_die) == DW_TAG_typedef); - - return vr_die; -} - -static int die_get_attr_udata(Dwarf_Die *tp_die, unsigned int attr_name, - Dwarf_Word *result) -{ - Dwarf_Attribute attr; - - if (dwarf_attr(tp_die, attr_name, &attr) == NULL || - dwarf_formudata(&attr, result) != 0) - return -ENOENT; - - return 0; -} -static bool die_is_signed_type(Dwarf_Die *tp_die) -{ - Dwarf_Word ret; - - if (die_get_attr_udata(tp_die, DW_AT_encoding, &ret)) - return false; - - return (ret == DW_ATE_signed_char || ret == DW_ATE_signed || - ret == DW_ATE_signed_fixed); -} - -static int die_get_byte_size(Dwarf_Die *tp_die) -{ - Dwarf_Word ret; - - if (die_get_attr_udata(tp_die, DW_AT_byte_size, &ret)) - return 0; - - return (int)ret; -} - -static int die_get_bit_size(Dwarf_Die *tp_die) -{ - Dwarf_Word ret; - - if (die_get_attr_udata(tp_die, DW_AT_bit_size, &ret)) - return 0; - - return (int)ret; -} - -static int die_get_bit_offset(Dwarf_Die *tp_die) -{ - Dwarf_Word ret; - - if (die_get_attr_udata(tp_die, DW_AT_bit_offset, &ret)) - return 0; - - return (int)ret; -} - -/* Get data_member_location offset */ -static int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs) -{ - Dwarf_Attribute attr; - Dwarf_Op *expr; - size_t nexpr; - int ret; - - if (dwarf_attr(mb_die, DW_AT_data_member_location, &attr) == NULL) - return -ENOENT; - - if (dwarf_formudata(&attr, offs) != 0) { - /* DW_AT_data_member_location should be DW_OP_plus_uconst */ - ret = dwarf_getlocation(&attr, &expr, &nexpr); - if (ret < 0 || nexpr == 0) - return -ENOENT; - - if (expr[0].atom != DW_OP_plus_uconst || nexpr != 1) { - pr_debug("Unable to get offset:Unexpected OP %x (%zd)\n", - expr[0].atom, nexpr); - return -ENOTSUP; - } - *offs = (Dwarf_Word)expr[0].number; - } - return 0; -} - -/* Return values for die_find callbacks */ -enum { - DIE_FIND_CB_FOUND = 0, /* End of Search */ - DIE_FIND_CB_CHILD = 1, /* Search only children */ - DIE_FIND_CB_SIBLING = 2, /* Search only siblings */ - DIE_FIND_CB_CONTINUE = 3, /* Search children and siblings */ -}; - -/* Search a child die */ -static Dwarf_Die *die_find_child(Dwarf_Die *rt_die, - int (*callback)(Dwarf_Die *, void *), - void *data, Dwarf_Die *die_mem) -{ - Dwarf_Die child_die; - int ret; - - ret = dwarf_child(rt_die, die_mem); - if (ret != 0) - return NULL; - - do { - ret = callback(die_mem, data); - if (ret == DIE_FIND_CB_FOUND) - return die_mem; - - if ((ret & DIE_FIND_CB_CHILD) && - die_find_child(die_mem, callback, data, &child_die)) { - memcpy(die_mem, &child_die, sizeof(Dwarf_Die)); - return die_mem; - } - } while ((ret & DIE_FIND_CB_SIBLING) && - dwarf_siblingof(die_mem, die_mem) == 0); - - return NULL; -} - -struct __addr_die_search_param { - Dwarf_Addr addr; - Dwarf_Die *die_mem; -}; - -static int __die_search_func_cb(Dwarf_Die *fn_die, void *data) -{ - struct __addr_die_search_param *ad = data; - - if (dwarf_tag(fn_die) == DW_TAG_subprogram && - dwarf_haspc(fn_die, ad->addr)) { - memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die)); - return DWARF_CB_ABORT; + if (debuginfo__init_online_kernel_dwarf(self, (Dwarf_Addr)addr) < 0) { + free(self); + self = NULL; } - return DWARF_CB_OK; -} -/* Search a real subprogram including this line, */ -static Dwarf_Die *die_find_real_subprogram(Dwarf_Die *cu_die, Dwarf_Addr addr, - Dwarf_Die *die_mem) -{ - struct __addr_die_search_param ad; - ad.addr = addr; - ad.die_mem = die_mem; - /* dwarf_getscopes can't find subprogram. */ - if (!dwarf_getfuncs(cu_die, __die_search_func_cb, &ad, 0)) - return NULL; - else - return die_mem; + return self; } -/* die_find callback for inline function search */ -static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data) +void debuginfo__delete(struct debuginfo *self) { - Dwarf_Addr *addr = data; - - if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine && - dwarf_haspc(die_mem, *addr)) - return DIE_FIND_CB_FOUND; - - return DIE_FIND_CB_CONTINUE; -} - -/* Similar to dwarf_getfuncs, but returns inlined_subroutine if exists. */ -static Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr, - Dwarf_Die *die_mem) -{ - Dwarf_Die tmp_die; - - sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr, &tmp_die); - if (!sp_die) - return NULL; - - /* Inlined function could be recursive. Trace it until fail */ - while (sp_die) { - memcpy(die_mem, sp_die, sizeof(Dwarf_Die)); - sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr, - &tmp_die); - } - - return die_mem; -} - -/* Walker on lines (Note: line number will not be sorted) */ -typedef int (* line_walk_handler_t) (const char *fname, int lineno, - Dwarf_Addr addr, void *data); - -struct __line_walk_param { - const char *fname; - line_walk_handler_t handler; - void *data; - int retval; -}; - -static int __die_walk_funclines_cb(Dwarf_Die *in_die, void *data) -{ - struct __line_walk_param *lw = data; - Dwarf_Addr addr; - int lineno; - - if (dwarf_tag(in_die) == DW_TAG_inlined_subroutine) { - lineno = die_get_call_lineno(in_die); - if (lineno > 0 && dwarf_entrypc(in_die, &addr) == 0) { - lw->retval = lw->handler(lw->fname, lineno, addr, - lw->data); - if (lw->retval != 0) - return DIE_FIND_CB_FOUND; - } + if (self) { + if (self->dwfl) + dwfl_end(self->dwfl); + free(self); } - return DIE_FIND_CB_SIBLING; -} - -/* Walk on lines of blocks included in given DIE */ -static int __die_walk_funclines(Dwarf_Die *sp_die, - line_walk_handler_t handler, void *data) -{ - struct __line_walk_param lw = { - .handler = handler, - .data = data, - .retval = 0, - }; - Dwarf_Die die_mem; - Dwarf_Addr addr; - int lineno; - - /* Handle function declaration line */ - lw.fname = dwarf_decl_file(sp_die); - if (lw.fname && dwarf_decl_line(sp_die, &lineno) == 0 && - dwarf_entrypc(sp_die, &addr) == 0) { - lw.retval = handler(lw.fname, lineno, addr, data); - if (lw.retval != 0) - goto done; - } - die_find_child(sp_die, __die_walk_funclines_cb, &lw, &die_mem); -done: - return lw.retval; -} - -static int __die_walk_culines_cb(Dwarf_Die *sp_die, void *data) -{ - struct __line_walk_param *lw = data; - - lw->retval = __die_walk_funclines(sp_die, lw->handler, lw->data); - if (lw->retval != 0) - return DWARF_CB_ABORT; - - return DWARF_CB_OK; -} - -/* - * Walk on lines inside given PDIE. If the PDIE is subprogram, walk only on - * the lines inside the subprogram, otherwise PDIE must be a CU DIE. - */ -static int die_walk_lines(Dwarf_Die *pdie, line_walk_handler_t handler, - void *data) -{ - Dwarf_Lines *lines; - Dwarf_Line *line; - Dwarf_Addr addr; - const char *fname; - int lineno, ret = 0; - Dwarf_Die die_mem, *cu_die; - size_t nlines, i; - - /* Get the CU die */ - if (dwarf_tag(pdie) == DW_TAG_subprogram) - cu_die = dwarf_diecu(pdie, &die_mem, NULL, NULL); - else - cu_die = pdie; - if (!cu_die) { - pr_debug2("Failed to get CU from subprogram\n"); - return -EINVAL; - } - - /* Get lines list in the CU */ - if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0) { - pr_debug2("Failed to get source lines on this CU.\n"); - return -ENOENT; - } - pr_debug2("Get %zd lines from this CU\n", nlines); - - /* Walk on the lines on lines list */ - for (i = 0; i < nlines; i++) { - line = dwarf_onesrcline(lines, i); - if (line == NULL || - dwarf_lineno(line, &lineno) != 0 || - dwarf_lineaddr(line, &addr) != 0) { - pr_debug2("Failed to get line info. " - "Possible error in debuginfo.\n"); - continue; - } - /* Filter lines based on address */ - if (pdie != cu_die) - /* - * Address filtering - * The line is included in given function, and - * no inline block includes it. - */ - if (!dwarf_haspc(pdie, addr) || - die_find_inlinefunc(pdie, addr, &die_mem)) - continue; - /* Get source line */ - fname = dwarf_linesrc(line, NULL, NULL); - - ret = handler(fname, lineno, addr, data); - if (ret != 0) - return ret; - } - - /* - * Dwarf lines doesn't include function declarations and inlined - * subroutines. We have to check functions list or given function. - */ - if (pdie != cu_die) - ret = __die_walk_funclines(pdie, handler, data); - else { - struct __line_walk_param param = { - .handler = handler, - .data = data, - .retval = 0, - }; - dwarf_getfuncs(cu_die, __die_walk_culines_cb, ¶m, 0); - ret = param.retval; - } - - return ret; -} - -struct __find_variable_param { - const char *name; - Dwarf_Addr addr; -}; - -static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data) -{ - struct __find_variable_param *fvp = data; - int tag; - - tag = dwarf_tag(die_mem); - if ((tag == DW_TAG_formal_parameter || - tag == DW_TAG_variable) && - die_compare_name(die_mem, fvp->name)) - return DIE_FIND_CB_FOUND; - - if (dwarf_haspc(die_mem, fvp->addr)) - return DIE_FIND_CB_CONTINUE; - else - return DIE_FIND_CB_SIBLING; -} - -/* Find a variable called 'name' at given address */ -static Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name, - Dwarf_Addr addr, Dwarf_Die *die_mem) -{ - struct __find_variable_param fvp = { .name = name, .addr = addr}; - - return die_find_child(sp_die, __die_find_variable_cb, (void *)&fvp, - die_mem); -} - -static int __die_find_member_cb(Dwarf_Die *die_mem, void *data) -{ - const char *name = data; - - if ((dwarf_tag(die_mem) == DW_TAG_member) && - die_compare_name(die_mem, name)) - return DIE_FIND_CB_FOUND; - - return DIE_FIND_CB_SIBLING; -} - -/* Find a member called 'name' */ -static Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name, - Dwarf_Die *die_mem) -{ - return die_find_child(st_die, __die_find_member_cb, (void *)name, - die_mem); -} - -/* Get the name of given variable DIE */ -static int die_get_typename(Dwarf_Die *vr_die, char *buf, int len) -{ - Dwarf_Die type; - int tag, ret, ret2; - const char *tmp = ""; - - if (__die_get_real_type(vr_die, &type) == NULL) - return -ENOENT; - - tag = dwarf_tag(&type); - if (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type) - tmp = "*"; - else if (tag == DW_TAG_subroutine_type) { - /* Function pointer */ - ret = snprintf(buf, len, "(function_type)"); - return (ret >= len) ? -E2BIG : ret; - } else { - if (!dwarf_diename(&type)) - return -ENOENT; - if (tag == DW_TAG_union_type) - tmp = "union "; - else if (tag == DW_TAG_structure_type) - tmp = "struct "; - /* Write a base name */ - ret = snprintf(buf, len, "%s%s", tmp, dwarf_diename(&type)); - return (ret >= len) ? -E2BIG : ret; - } - ret = die_get_typename(&type, buf, len); - if (ret > 0) { - ret2 = snprintf(buf + ret, len - ret, "%s", tmp); - ret = (ret2 >= len - ret) ? -E2BIG : ret2 + ret; - } - return ret; -} - -/* Get the name and type of given variable DIE, stored as "type\tname" */ -static int die_get_varname(Dwarf_Die *vr_die, char *buf, int len) -{ - int ret, ret2; - - ret = die_get_typename(vr_die, buf, len); - if (ret < 0) { - pr_debug("Failed to get type, make it unknown.\n"); - ret = snprintf(buf, len, "(unknown_type)"); - } - if (ret > 0) { - ret2 = snprintf(buf + ret, len - ret, "\t%s", - dwarf_diename(vr_die)); - ret = (ret2 >= len - ret) ? -E2BIG : ret2 + ret; - } - return ret; } /* @@ -897,6 +374,7 @@ static int convert_variable_type(Dwarf_Die *vr_die, struct probe_trace_arg_ref **ref_ptr = &tvar->ref; Dwarf_Die type; char buf[16]; + int bsize, boffs, total; int ret; /* TODO: check all types */ @@ -906,11 +384,15 @@ static int convert_variable_type(Dwarf_Die *vr_die, return (tvar->type == NULL) ? -ENOMEM : 0; } - if (die_get_bit_size(vr_die) != 0) { + bsize = dwarf_bitsize(vr_die); + if (bsize > 0) { /* This is a bitfield */ - ret = snprintf(buf, 16, "b%d@%d/%zd", die_get_bit_size(vr_die), - die_get_bit_offset(vr_die), - BYTES_TO_BITS(die_get_byte_size(vr_die))); + boffs = dwarf_bitoffset(vr_die); + total = dwarf_bytesize(vr_die); + if (boffs < 0 || total < 0) + return -ENOENT; + ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs, + BYTES_TO_BITS(total)); goto formatted; } @@ -958,10 +440,11 @@ static int convert_variable_type(Dwarf_Die *vr_die, return (tvar->type == NULL) ? -ENOMEM : 0; } - ret = BYTES_TO_BITS(die_get_byte_size(&type)); - if (!ret) + 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) { @@ -1025,7 +508,7 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, else *ref_ptr = ref; } - ref->offset += die_get_byte_size(&type) * field->index; + ref->offset += dwarf_bytesize(&type) * field->index; if (!field->next) /* Save vr_die for converting types */ memcpy(die_mem, vr_die, sizeof(*die_mem)); @@ -1129,12 +612,12 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf) return ret; } -/* Find a variable in a subprogram die */ -static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf) +/* Find a variable in a scope DIE */ +static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf) { - Dwarf_Die vr_die, *scopes; + Dwarf_Die vr_die; char buf[32], *ptr; - int ret, nscopes; + int ret = 0; if (!is_c_varname(pf->pvar->var)) { /* Copy raw parameters */ @@ -1169,30 +652,16 @@ static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf) if (pf->tvar->name == NULL) return -ENOMEM; - pr_debug("Searching '%s' variable in context.\n", - pf->pvar->var); + pr_debug("Searching '%s' variable in context.\n", pf->pvar->var); /* Search child die for local variables and parameters. */ - if (die_find_variable_at(sp_die, pf->pvar->var, pf->addr, &vr_die)) - ret = convert_variable(&vr_die, pf); - else { - /* Search upper class */ - nscopes = dwarf_getscopes_die(sp_die, &scopes); - while (nscopes-- > 1) { - pr_debug("Searching variables in %s\n", - dwarf_diename(&scopes[nscopes])); - /* We should check this scope, so give dummy address */ - if (die_find_variable_at(&scopes[nscopes], - pf->pvar->var, 0, - &vr_die)) { - ret = convert_variable(&vr_die, pf); - goto found; - } - } - if (scopes) - free(scopes); - ret = -ENOENT; + 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; } -found: + 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); @@ -1235,27 +704,30 @@ static int convert_to_trace_point(Dwarf_Die *sp_die, Dwarf_Addr paddr, return 0; } -/* Call probe_finder callback with real subprogram DIE */ -static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf) +/* Call probe_finder callback with scope DIE */ +static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf) { - Dwarf_Die die_mem; Dwarf_Attribute fb_attr; size_t nops; int ret; - /* If no real subprogram, find a real one */ - if (!sp_die || dwarf_tag(sp_die) != DW_TAG_subprogram) { - sp_die = die_find_real_subprogram(&pf->cu_die, - pf->addr, &die_mem); - if (!sp_die) { + 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 */ - dwarf_attr(sp_die, DW_AT_frame_base, &fb_attr); + /* 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; @@ -1273,7 +745,7 @@ static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf) } /* Call finder's callback handler */ - ret = pf->callback(sp_die, pf); + ret = pf->callback(sc_die, pf); /* *pf->fb_ops will be cached in libdw. Don't free it. */ pf->fb_ops = NULL; @@ -1281,17 +753,82 @@ static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf) 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; - ret = call_probe_finder(NULL, pf); + 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; @@ -1345,6 +882,7 @@ 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) || @@ -1354,7 +892,14 @@ static int probe_point_lazy_walker(const char *fname, int lineno, pr_debug("Probe line found: line:%d addr:0x%llx\n", lineno, (unsigned long long)addr); pf->addr = addr; - ret = call_probe_finder(NULL, pf); + 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 @@ -1379,42 +924,39 @@ static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf) return die_walk_lines(sp_die, probe_point_lazy_walker, pf); } -/* Callback parameter with return value */ -struct dwarf_callback_param { - void *data; - int retval; -}; - static int probe_point_inline_cb(Dwarf_Die *in_die, void *data) { - struct dwarf_callback_param *param = data; - struct probe_finder *pf = param->data; + struct probe_finder *pf = data; struct perf_probe_point *pp = &pf->pev->point; Dwarf_Addr addr; + int ret; if (pp->lazy_line) - param->retval = find_probe_point_lazy(in_die, pf); + 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)); - param->retval = -ENOENT; - return DWARF_CB_ABORT; + return -ENOENT; } pf->addr = addr; pf->addr += pp->offset; pr_debug("found inline addr: 0x%jx\n", (uintmax_t)pf->addr); - param->retval = call_probe_finder(in_die, pf); - if (param->retval < 0) - return DWARF_CB_ABORT; + ret = call_probe_finder(in_die, pf); } - return DWARF_CB_OK; + 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) { @@ -1451,14 +993,10 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data) /* TODO: Check the address in this function */ param->retval = call_probe_finder(sp_die, pf); } - } else { - struct dwarf_callback_param _param = {.data = (void *)pf, - .retval = 0}; + } else /* Inlined function: search instances */ - dwarf_func_inline_instances(sp_die, probe_point_inline_cb, - &_param); - param->retval = _param.retval; - } + param->retval = die_walk_instances(sp_die, + probe_point_inline_cb, (void *)pf); return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */ } @@ -1504,28 +1042,18 @@ static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data) } /* Find probe points from debuginfo */ -static int find_probes(int fd, struct probe_finder *pf) +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; - Dwarf *dbg = NULL; - Dwfl *dwfl; - Dwarf_Addr bias; /* Currently ignored */ int ret = 0; - dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias); - if (!dbg) { - pr_warning("No debug information found in the vmlinux - " - "please rebuild with CONFIG_DEBUG_INFO=y.\n"); - close(fd); /* Without dwfl_end(), fd isn't closed. */ - return -EBADF; - } - #if _ELFUTILS_PREREQ(0, 142) /* Get the call frame information from this dwarf */ - pf->cfi = dwarf_getcfi(dbg); + pf->cfi = dwarf_getcfi(self->dbg); #endif off = 0; @@ -1544,7 +1072,8 @@ static int find_probes(int fd, struct probe_finder *pf) .data = pf, }; - dwarf_getpubnames(dbg, pubname_search_cb, &pubname_param, 0); + 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) @@ -1553,9 +1082,9 @@ static int find_probes(int fd, struct probe_finder *pf) } /* Loop on CUs (Compilation Unit) */ - while (!dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL)) { + while (!dwarf_nextcu(self->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) { /* Get the DIE(Debugging Information Entry) of this CU */ - diep = dwarf_offdie(dbg, off + cuhl, &pf->cu_die); + diep = dwarf_offdie(self->dbg, off + cuhl, &pf->cu_die); if (!diep) continue; @@ -1582,14 +1111,12 @@ static int find_probes(int fd, struct probe_finder *pf) found: line_list__free(&pf->lcache); - if (dwfl) - dwfl_end(dwfl); return ret; } /* Add a found probe point into trace event list */ -static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf) +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); @@ -1604,8 +1131,9 @@ static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf) } tev = &tf->tevs[tf->ntevs++]; - ret = convert_to_trace_point(sp_die, pf->addr, pf->pev->point.retprobe, - &tev->point); + /* 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; @@ -1620,7 +1148,8 @@ static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf) for (i = 0; i < pf->pev->nargs; i++) { pf->pvar = &pf->pev->args[i]; pf->tvar = &tev->args[i]; - ret = find_variable(sp_die, pf); + /* Variable should be found from scope DIE */ + ret = find_variable(sc_die, pf); if (ret != 0) return ret; } @@ -1629,8 +1158,9 @@ static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf) } /* Find probe_trace_events specified by perf_probe_event from debuginfo */ -int find_probe_trace_events(int fd, struct perf_probe_event *pev, - struct probe_trace_event **tevs, int max_tevs) +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}, @@ -1645,7 +1175,7 @@ int find_probe_trace_events(int fd, struct perf_probe_event *pev, tf.tevs = *tevs; tf.ntevs = 0; - ret = find_probes(fd, &tf.pf); + ret = debuginfo__find_probes(self, &tf.pf); if (ret < 0) { free(*tevs); *tevs = NULL; @@ -1687,13 +1217,13 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data) } /* Add a found vars into available variables list */ -static int add_available_vars(Dwarf_Die *sp_die, struct probe_finder *pf) +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, *scopes = NULL; - int ret, nscopes; + Dwarf_Die die_mem; + int ret; /* Check number of tevs */ if (af->nvls == af->max_vls) { @@ -1702,8 +1232,9 @@ static int add_available_vars(Dwarf_Die *sp_die, struct probe_finder *pf) } vl = &af->vls[af->nvls++]; - ret = convert_to_trace_point(sp_die, pf->addr, pf->pev->point.retprobe, - &vl->point); + /* 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; @@ -1715,19 +1246,14 @@ static int add_available_vars(Dwarf_Die *sp_die, struct probe_finder *pf) if (vl->vars == NULL) return -ENOMEM; af->child = true; - die_find_child(sp_die, collect_variables_cb, (void *)af, &die_mem); + 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; - nscopes = dwarf_getscopes_die(sp_die, &scopes); - while (nscopes-- > 1) - die_find_child(&scopes[nscopes], collect_variables_cb, - (void *)af, &die_mem); - if (scopes) - free(scopes); + die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem); out: if (strlist__empty(vl->vars)) { @@ -1739,9 +1265,10 @@ out: } /* Find available variables at given probe point */ -int find_available_vars_at(int fd, struct perf_probe_event *pev, - struct variable_list **vls, int max_vls, - bool externs) +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}, @@ -1756,7 +1283,7 @@ int find_available_vars_at(int fd, struct perf_probe_event *pev, af.vls = *vls; af.nvls = 0; - ret = find_probes(fd, &af.pf); + ret = debuginfo__find_probes(self, &af.pf); if (ret < 0) { /* Free vlist for error */ while (af.nvls--) { @@ -1774,28 +1301,19 @@ int find_available_vars_at(int fd, struct perf_probe_event *pev, } /* Reverse search */ -int find_perf_probe_point(unsigned long addr, struct perf_probe_point *ppt) +int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr, + struct perf_probe_point *ppt) { Dwarf_Die cudie, spdie, indie; - Dwarf *dbg = NULL; - Dwfl *dwfl = NULL; - Dwarf_Addr _addr, baseaddr, bias = 0; + Dwarf_Addr _addr, baseaddr; const char *fname = NULL, *func = NULL, *tmp; int baseline = 0, lineno = 0, ret = 0; - /* Open the live linux kernel */ - dbg = dwfl_init_live_kernel_dwarf(addr, &dwfl, &bias); - if (!dbg) { - pr_warning("No debug information found in the vmlinux - " - "please rebuild with CONFIG_DEBUG_INFO=y.\n"); - ret = -EINVAL; - goto end; - } - /* Adjust address with bias */ - addr += bias; + addr += self->bias; + /* Find cu die */ - if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr - bias, &cudie)) { + 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; @@ -1807,7 +1325,7 @@ int find_perf_probe_point(unsigned long addr, struct perf_probe_point *ppt) /* Don't care whether it failed or not */ /* Find a corresponding function (name, baseline and baseaddr) */ - if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) { + if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) { /* Get function entry information */ tmp = dwarf_diename(&spdie); if (!tmp || @@ -1871,8 +1389,6 @@ post: } } end: - if (dwfl) - dwfl_end(dwfl); if (ret == 0 && (fname || func)) ret = 1; /* Found a point */ return ret; @@ -1929,10 +1445,14 @@ static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf) static int line_range_inline_cb(Dwarf_Die *in_die, void *data) { - struct dwarf_callback_param *param = data; + find_line_range_by_line(in_die, data); - param->retval = find_line_range_by_line(in_die, param->data); - return DWARF_CB_ABORT; /* No need to find other instances */ + /* + * 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 */ @@ -1960,15 +1480,10 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data) 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)) { - struct dwarf_callback_param _param; - _param.data = (void *)lf; - _param.retval = 0; - dwarf_func_inline_instances(sp_die, - line_range_inline_cb, - &_param); - param->retval = _param.retval; - } else + 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; } @@ -1982,26 +1497,15 @@ static int find_line_range_by_func(struct line_finder *lf) return param.retval; } -int find_line_range(int fd, struct line_range *lr) +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; - Dwarf *dbg = NULL; - Dwfl *dwfl; - Dwarf_Addr bias; /* Currently ignored */ const char *comp_dir; - dbg = dwfl_init_offline_dwarf(fd, &dwfl, &bias); - if (!dbg) { - pr_warning("No debug information found in the vmlinux - " - "please rebuild with CONFIG_DEBUG_INFO=y.\n"); - close(fd); /* Without dwfl_end(), fd isn't closed. */ - return -EBADF; - } - /* Fastpath: lookup by function name from .debug_pubnames section */ if (lr->function) { struct pubname_callback_param pubname_param = { @@ -2010,7 +1514,8 @@ int find_line_range(int fd, struct line_range *lr) struct dwarf_callback_param line_range_param = { .data = (void *)&lf, .retval = 0}; - dwarf_getpubnames(dbg, pubname_search_cb, &pubname_param, 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) @@ -2020,11 +1525,12 @@ int find_line_range(int fd, struct line_range *lr) /* Loop on CUs (Compilation Unit) */ while (!lf.found && ret >= 0) { - if (dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 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(dbg, off + cuhl, &lf.cu_die); + diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die); if (!diep) continue; @@ -2058,7 +1564,6 @@ found: } pr_debug("path: %s\n", lr->path); - dwfl_end(dwfl); return (ret < 0) ? ret : lf.found; } |