diff options
Diffstat (limited to 'tools/perf/util/probe-finder.c')
| -rw-r--r-- | tools/perf/util/probe-finder.c | 1727 |
1 files changed, 946 insertions, 781 deletions
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 840f1aabbb7..98e30476641 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -30,12 +30,13 @@ #include <stdlib.h> #include <string.h> #include <stdarg.h> -#include <ctype.h> #include <dwarf-regs.h> -#include "string.h" +#include <linux/bitops.h> #include "event.h" +#include "dso.h" #include "debug.h" +#include "intlist.h" #include "util.h" #include "symbol.h" #include "probe-finder.h" @@ -43,323 +44,107 @@ /* 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 */ -static int line_list__add_line(struct list_head *head, int line) -{ - struct line_node *ln; - struct list_head *p; - - /* Reverse search, because new line will be the last one */ - list_for_each_entry_reverse(ln, head, list) { - if (ln->line < line) { - p = &ln->list; - goto found; - } else if (ln->line == line) /* Already exist */ - return 1; - } - /* List is empty, or the smallest entry */ - p = head; -found: - pr_debug("line list: add a line %u\n", line); - ln = zalloc(sizeof(struct line_node)); - if (ln == NULL) - return -ENOMEM; - ln->line = line; - INIT_LIST_HEAD(&ln->list); - list_add(&ln->list, p); - return 0; -} - -/* Check if the line in line number list */ -static int line_list__has_line(struct list_head *head, int line) -{ - struct line_node *ln; +/* Dwarf FL wrappers */ +static char *debuginfo_path; /* Currently dummy */ - /* Reverse search, because new line will be the last one */ - list_for_each_entry(ln, head, list) - if (ln->line == line) - return 1; +static const Dwfl_Callbacks offline_callbacks = { + .find_debuginfo = dwfl_standard_find_debuginfo, + .debuginfo_path = &debuginfo_path, - return 0; -} + .section_address = dwfl_offline_section_address, -/* Init line number list */ -static void line_list__init(struct list_head *head) -{ - INIT_LIST_HEAD(head); -} - -/* Free line number list */ -static void line_list__free(struct list_head *head) -{ - struct line_node *ln; - while (!list_empty(head)) { - ln = list_first_entry(head, struct line_node, list); - list_del(&ln->list); - free(ln); - } -} - -/* Dwarf wrappers */ - -/* Find the realpath of the target file. */ -static const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname) -{ - Dwarf_Files *files; - size_t nfiles, i; - const char *src = NULL; - int ret; - - if (!fname) - 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 (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); -} - -/* 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 type die, but skip qualifiers and typedef */ -static Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem) -{ - Dwarf_Attribute attr; - int tag; - - do { - if (dwarf_attr(vr_die, DW_AT_type, &attr) == NULL || - dwarf_formref_die(&attr, die_mem) == NULL) - return NULL; - - tag = dwarf_tag(die_mem); - vr_die = die_mem; - } while (tag == DW_TAG_const_type || - tag == DW_TAG_restrict_type || - tag == DW_TAG_volatile_type || - tag == DW_TAG_shared_type || - tag == DW_TAG_typedef); - - return die_mem; -} + /* We use this table for core files too. */ + .find_elf = dwfl_build_id_find_elf, +}; -static bool die_is_signed_type(Dwarf_Die *tp_die) +/* Get a Dwarf from offline image */ +static int debuginfo__init_offline_dwarf(struct debuginfo *dbg, + const char *path) { - Dwarf_Attribute attr; - Dwarf_Word ret; - - if (dwarf_attr(tp_die, DW_AT_encoding, &attr) == NULL || - dwarf_formudata(&attr, &ret) != 0) - return false; - - return (ret == DW_ATE_signed_char || ret == DW_ATE_signed || - ret == DW_ATE_signed_fixed); -} + int fd; -static int die_get_byte_size(Dwarf_Die *tp_die) -{ - Dwarf_Attribute attr; - Dwarf_Word ret; + fd = open(path, O_RDONLY); + if (fd < 0) + return fd; - if (dwarf_attr(tp_die, DW_AT_byte_size, &attr) == NULL || - dwarf_formudata(&attr, &ret) != 0) - return 0; + dbg->dwfl = dwfl_begin(&offline_callbacks); + if (!dbg->dwfl) + goto error; - return (int)ret; -} + dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd); + if (!dbg->mod) + goto error; -/* 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; + dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias); + if (!dbg->dbg) + goto error; - 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; -} +error: + if (dbg->dwfl) + dwfl_end(dbg->dwfl); + else + close(fd); + memset(dbg, 0, sizeof(*dbg)); -/* 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 */ -}; + return -ENOENT; +} -/* 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) +static struct debuginfo *__debuginfo__new(const char *path) { - Dwarf_Die child_die; - int ret; - - ret = dwarf_child(rt_die, die_mem); - if (ret != 0) + struct debuginfo *dbg = zalloc(sizeof(*dbg)); + if (!dbg) 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; + if (debuginfo__init_offline_dwarf(dbg, path) < 0) + zfree(&dbg); + if (dbg) + pr_debug("Open Debuginfo file: %s\n", path); + return dbg; } -struct __addr_die_search_param { - Dwarf_Addr addr; - Dwarf_Die *die_mem; +enum dso_binary_type distro_dwarf_types[] = { + DSO_BINARY_TYPE__FEDORA_DEBUGINFO, + DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, + DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, + DSO_BINARY_TYPE__BUILDID_DEBUGINFO, + DSO_BINARY_TYPE__NOT_FOUND, }; -static int __die_search_func_cb(Dwarf_Die *fn_die, void *data) +struct debuginfo *debuginfo__new(const char *path) { - 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; + enum dso_binary_type *type; + char buf[PATH_MAX], nil = '\0'; + struct dso *dso; + struct debuginfo *dinfo = NULL; + + /* Try to open distro debuginfo files */ + dso = dso__new(path); + if (!dso) + goto out; + + for (type = distro_dwarf_types; + !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND; + type++) { + if (dso__read_binary_type_filename(dso, *type, &nil, + buf, PATH_MAX) < 0) + continue; + dinfo = __debuginfo__new(buf); } - 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; -} - -/* die_find callback for inline function search */ -static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data) -{ - 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) -{ - return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem); -} - -static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data) -{ - const char *name = data; - int tag; + dso__delete(dso); - tag = dwarf_tag(die_mem); - if ((tag == DW_TAG_formal_parameter || - tag == DW_TAG_variable) && - die_compare_name(die_mem, name)) - return DIE_FIND_CB_FOUND; - - return DIE_FIND_CB_CONTINUE; +out: + /* if failed to open all distro debuginfo, open given binary */ + return dinfo ? : __debuginfo__new(path); } -/* Find a variable called 'name' */ -static Dwarf_Die *die_find_variable(Dwarf_Die *sp_die, const char *name, - Dwarf_Die *die_mem) +void debuginfo__delete(struct debuginfo *dbg) { - return die_find_child(sp_die, __die_find_variable_cb, (void *)name, - 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); + if (dbg) { + if (dbg->dwfl) + dwfl_end(dbg->dwfl); + free(dbg); + } } /* @@ -375,30 +160,58 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs) return ref; } -/* Show a location */ -static int convert_variable_location(Dwarf_Die *vr_die, struct probe_finder *pf) +/* + * Convert a location into trace_arg. + * If tvar == NULL, this just checks variable can be converted. + * If fentry == true and vr_die is a parameter, do huristic search + * for the location fuzzed by function entry mcount. + */ +static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr, + Dwarf_Op *fb_ops, Dwarf_Die *sp_die, + struct probe_trace_arg *tvar) { Dwarf_Attribute attr; + Dwarf_Addr tmp = 0; Dwarf_Op *op; size_t nops; unsigned int regn; Dwarf_Word offs = 0; bool ref = false; const char *regs; - struct probe_trace_arg *tvar = pf->tvar; int ret; + if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL) + goto static_var; + /* TODO: handle more than 1 exprs */ - if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL || - dwarf_getlocation_addr(&attr, pf->addr, &op, &nops, 1) <= 0 || - nops == 0) { - /* TODO: Support const_value */ - pr_err("Failed to find the location of %s at this address.\n" - " Perhaps, it has been optimized out.\n", pf->pvar->var); + if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL) + return -EINVAL; /* Broken DIE ? */ + if (dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0) { + ret = dwarf_entrypc(sp_die, &tmp); + if (ret || addr != tmp || + dwarf_tag(vr_die) != DW_TAG_formal_parameter || + dwarf_highpc(sp_die, &tmp)) + return -ENOENT; + /* + * This is fuzzed by fentry mcount. We try to find the + * parameter location at the earliest address. + */ + for (addr += 1; addr <= tmp; addr++) { + if (dwarf_getlocation_addr(&attr, addr, &op, + &nops, 1) > 0) + goto found; + } return -ENOENT; } +found: + if (nops == 0) + /* TODO: Support const_value */ + return -ENOENT; if (op->atom == DW_OP_addr) { +static_var: + if (!tvar) + return 0; /* Static variables on memory (not stack), make @varname */ ret = strlen(dwarf_diename(vr_die)); tvar->value = zalloc(ret + 2); @@ -413,14 +226,11 @@ static int convert_variable_location(Dwarf_Die *vr_die, struct probe_finder *pf) /* If this is based on frame buffer, set the offset */ if (op->atom == DW_OP_fbreg) { - if (pf->fb_ops == NULL) { - pr_warning("The attribute of frame base is not " - "supported.\n"); + if (fb_ops == NULL) return -ENOTSUP; - } ref = true; offs = op->number; - op = &pf->fb_ops[0]; + op = &fb_ops[0]; } if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) { @@ -436,13 +246,18 @@ static int convert_variable_location(Dwarf_Die *vr_die, struct probe_finder *pf) } else if (op->atom == DW_OP_regx) { regn = op->number; } else { - pr_warning("DW_OP %x is not supported.\n", op->atom); + pr_debug("DW_OP %x is not supported.\n", op->atom); return -ENOTSUP; } + if (!tvar) + return 0; + regs = get_arch_regstr(regn); if (!regs) { - pr_warning("Mapping for DWARF register number %u missing on this architecture.", regn); + /* This should be a bug in DWARF or this tool */ + pr_warning("Mapping for the register number %u " + "missing on this architecture.\n", regn); return -ERANGE; } @@ -458,6 +273,8 @@ static int convert_variable_location(Dwarf_Die *vr_die, struct probe_finder *pf) return 0; } +#define BYTES_TO_BITS(nb) ((nb) * BITS_PER_LONG / sizeof(long)) + static int convert_variable_type(Dwarf_Die *vr_die, struct probe_trace_arg *tvar, const char *cast) @@ -465,6 +282,7 @@ 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 */ @@ -474,6 +292,18 @@ static int convert_variable_type(Dwarf_Die *vr_die, return (tvar->type == NULL) ? -ENOMEM : 0; } + bsize = dwarf_bitsize(vr_die); + if (bsize > 0) { + /* This is a bitfield */ + 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; + } + if (die_get_real_type(vr_die, &type) == NULL) { pr_warning("Failed to get a type information of %s.\n", dwarf_diename(vr_die)); @@ -488,15 +318,16 @@ static int convert_variable_type(Dwarf_Die *vr_die, if (ret != DW_TAG_pointer_type && ret != DW_TAG_array_type) { pr_warning("Failed to cast into string: " - "%s(%s) is not a pointer nor array.", + "%s(%s) is not a pointer nor array.\n", dwarf_diename(vr_die), dwarf_diename(&type)); return -EINVAL; } + if (die_get_real_type(&type, &type) == NULL) { + pr_warning("Failed to get a type" + " information.\n"); + return -ENOENT; + } if (ret == DW_TAG_pointer_type) { - if (die_get_real_type(&type, &type) == NULL) { - pr_warning("Failed to get a type information."); - return -ENOENT; - } while (*ref_ptr) ref_ptr = &(*ref_ptr)->next; /* Add new reference with offset +0 */ @@ -509,7 +340,7 @@ static int convert_variable_type(Dwarf_Die *vr_die, if (!die_compare_name(&type, "char") && !die_compare_name(&type, "unsigned char")) { pr_warning("Failed to cast into string: " - "%s is not (unsigned) char *.", + "%s is not (unsigned) char *.\n", dwarf_diename(vr_die)); return -EINVAL; } @@ -517,29 +348,32 @@ static int convert_variable_type(Dwarf_Die *vr_die, return (tvar->type == NULL) ? -ENOMEM : 0; } - ret = die_get_byte_size(&type) * 8; - if (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 = dwarf_bytesize(&type); + if (ret <= 0) + /* No size ... try to use default type */ + return 0; + ret = BYTES_TO_BITS(ret); - ret = snprintf(buf, 16, "%c%d", - die_is_signed_type(&type) ? 's' : 'u', ret); - 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; + /* 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; } @@ -582,7 +416,7 @@ 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)); @@ -600,8 +434,10 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, return -ENOENT; } /* Verify it is a data structure */ - if (dwarf_tag(&type) != DW_TAG_structure_type) { - pr_warning("%s is not a data structure.\n", varname); + 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; } @@ -614,13 +450,14 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, *ref_ptr = ref; } else { /* Verify it is a data structure */ - if (tag != DW_TAG_structure_type) { - pr_warning("%s is not a data structure.\n", varname); + 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.", - varname); + pr_err("Semantic error: %s is not a pointor" + " nor array.\n", varname); return -EINVAL; } if (field->ref) { @@ -636,16 +473,21 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, } if (die_find_member(&type, field->name, die_mem) == NULL) { - pr_warning("%s(tyep:%s) has no member %s.\n", varname, + pr_warning("%s(type:%s) has no member %s.\n", varname, dwarf_diename(&type), field->name); return -EINVAL; } /* Get the offset of the field */ - 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; + 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; @@ -667,8 +509,14 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf) pr_debug("Converting variable %s into trace event.\n", dwarf_diename(vr_die)); - ret = convert_variable_location(vr_die, pf); - if (ret == 0 && pf->pvar->field) { + ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops, + &pf->sp_die, pf->tvar); + if (ret == -ENOENT || ret == -EINVAL) + 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 (ret == 0 && pf->pvar->field) { ret = convert_variable_fields(vr_die, pf->pvar->var, pf->pvar->field, &pf->tvar->ref, &die_mem); @@ -680,12 +528,31 @@ 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 */ + 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); @@ -701,90 +568,97 @@ static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf) if (pf->tvar->name == NULL) return -ENOMEM; - if (!is_c_varname(pf->pvar->var)) { - /* Copy raw parameters */ - pf->tvar->value = strdup(pf->pvar->var); - if (pf->tvar->value == NULL) - return -ENOMEM; - else - return 0; - } - - 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(sp_die, pf->pvar->var, &vr_die)) - ret = convert_variable(&vr_die, pf); - else { - /* Search upper class */ - nscopes = dwarf_getscopes_die(sp_die, &scopes); - if (nscopes > 0) { - ret = dwarf_getscopevar(scopes, nscopes, pf->pvar->var, - 0, NULL, 0, 0, &vr_die); - if (ret >= 0) - ret = convert_variable(&vr_die, pf); - else - ret = -ENOENT; - free(scopes); - } else + 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)) + pr_warning("Failed to find '%s' in this function.\n", + pf->pvar->var); ret = -ENOENT; } - if (ret < 0) - pr_warning("Failed to find '%s' in this function.\n", - pf->pvar->var); + if (ret >= 0) + ret = convert_variable(&vr_die, pf); + return ret; } -/* Show a probe point to output buffer */ -static int convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf) +/* Convert subprogram DIE to trace point */ +static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod, + Dwarf_Addr paddr, bool retprobe, + struct probe_trace_point *tp) +{ + Dwarf_Addr eaddr, highaddr; + GElf_Sym sym; + const char *symbol; + + /* Verify the address is correct */ + 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; + } + + /* Get an appropriate symbol from symtab */ + symbol = dwfl_module_addrsym(mod, paddr, &sym, NULL); + if (!symbol) { + pr_warning("Failed to find symbol at 0x%lx\n", + (unsigned long)paddr); + return -ENOENT; + } + tp->offset = (unsigned long)(paddr - sym.st_value); + tp->address = (unsigned long)paddr; + tp->symbol = strdup(symbol); + if (!tp->symbol) + return -ENOMEM; + + /* 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) { - struct probe_trace_event *tev; - Dwarf_Addr eaddr; - Dwarf_Die die_mem; - const char *name; - int ret, i; Dwarf_Attribute fb_attr; size_t nops; + int ret; - if (pf->ntevs == pf->max_tevs) { - pr_warning("Too many( > %d) probe point found.\n", - pf->max_tevs); - return -ERANGE; + if (!sc_die) { + pr_err("Caller must pass a scope DIE. Program error.\n"); + return -EINVAL; } - tev = &pf->tevs[pf->ntevs++]; - /* 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 not a real subprogram, find a real one */ + if (!die_is_func_def(sc_die)) { + 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; } - } - - /* 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 pc of %s\n", - dwarf_diename(sp_die)); - return -ENOENT; - } - tev->point.symbol = strdup(name); - if (tev->point.symbol == NULL) - return -ENOMEM; - tev->point.offset = (unsigned long)(pf->addr - eaddr); } else - /* This function has no name. */ - tev->point.offset = (unsigned long)pf->addr; + memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die)); - pr_debug("Probe point found: %s+%lu\n", tev->point.symbol, - tev->point.offset); - - /* 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; @@ -794,220 +668,226 @@ static int convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf) 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 CFA on 0x%jx\n", + pr_warning("Failed to get call frame on 0x%jx\n", (uintmax_t)pf->addr); return -ENOENT; } #endif } - /* 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]; - ret = find_variable(sp_die, pf); - if (ret != 0) - return ret; - } + /* 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 probe point from its line number */ -static int find_probe_point_by_line(struct probe_finder *pf) +/* Find an appropriate scope fits to given conditions */ +static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem) { - Dwarf_Lines *lines; - Dwarf_Line *line; - size_t nlines, i; - Dwarf_Addr addr; - int lineno; - int ret = 0; + 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 (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) { - pr_warning("No source lines found in this CU.\n"); + 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; } - for (i = 0; i < nlines && ret == 0; i++) { - line = dwarf_onesrcline(lines, i); - if (dwarf_lineno(line, &lineno) != 0 || - lineno != pf->lno) - continue; - - /* TODO: Get fileno from line, but how? */ - if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0) - continue; + ret = call_probe_finder(sc_die, pf); - if (dwarf_lineaddr(line, &addr) != 0) { - pr_warning("Failed to get the address of the line.\n"); - return -ENOENT; - } - pr_debug("Probe line found: line[%d]:%d addr:0x%jx\n", - (int)i, lineno, (uintmax_t)addr); - pf->addr = addr; + /* Continue if no error, because the line will be in inline function */ + return ret < 0 ? ret : 0; +} - ret = convert_probe_point(NULL, pf); - /* Continuing, because target line might be inlined. */ - } - return ret; +/* 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, +static int find_lazy_match_lines(struct intlist *list, const char *fname, const char *pat) { - char *fbuf, *p1, *p2; - int fd, line, nlines = -1; - struct stat st; - - fd = open(fname, O_RDONLY); - if (fd < 0) { - pr_warning("Failed to open %s: %s\n", fname, strerror(-fd)); + 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; } - if (fstat(fd, &st) < 0) { - pr_warning("Failed to get the size of %s: %s\n", - fname, strerror(errno)); - nlines = -errno; - goto out_close; - } + while ((len = getline(&line, &line_len, fp)) > 0) { - nlines = -ENOMEM; - fbuf = malloc(st.st_size + 2); - if (fbuf == NULL) - goto out_close; - if (read(fd, fbuf, st.st_size) < 0) { - pr_warning("Failed to read %s: %s\n", fname, strerror(errno)); - nlines = -errno; - goto out_free_fbuf; - } - fbuf[st.st_size] = '\n'; /* Dummy line */ - fbuf[st.st_size + 1] = '\0'; - p1 = fbuf; - line = 1; - nlines = 0; - while ((p2 = strchr(p1, '\n')) != NULL) { - *p2 = '\0'; - if (strlazymatch(p1, pat)) { - line_list__add_line(head, line); - nlines++; + if (line[len - 1] == '\n') + line[len - 1] = '\0'; + + if (strlazymatch(line, pat)) { + intlist__add(list, linenum); + count++; } - line++; - p1 = p2 + 1; + linenum++; } -out_free_fbuf: - free(fbuf); -out_close: - close(fd); - return nlines; + + if (ferror(fp)) + count = -errno; + free(line); + fclose(fp); + + if (count == 0) + pr_debug("No matched lines found in %s.\n", fname); + return count; } -/* Find probe points from lazy pattern */ -static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf) +static int probe_point_lazy_walker(const char *fname, int lineno, + Dwarf_Addr addr, void *data) { - Dwarf_Lines *lines; - Dwarf_Line *line; - size_t nlines, i; - Dwarf_Addr addr; - Dwarf_Die die_mem; - int lineno; - int ret = 0; + struct probe_finder *pf = data; + Dwarf_Die *sc_die, die_mem; + int ret; - 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) { - pr_debug("No matched lines found in %s.\n", pf->fname); - return 0; - } else if (ret < 0) - return ret; - } + if (!intlist__has_entry(pf->lcache, lineno) || + strtailcmp(fname, pf->fname) != 0) + return 0; - if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) { - pr_warning("No source lines found in this CU.\n"); + 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; } - for (i = 0; i < nlines && ret >= 0; i++) { - line = dwarf_onesrcline(lines, i); + ret = call_probe_finder(sc_die, pf); - if (dwarf_lineno(line, &lineno) != 0 || - !line_list__has_line(&pf->lcache, lineno)) - continue; - - /* TODO: Get fileno from line, but how? */ - if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0) - continue; - - if (dwarf_lineaddr(line, &addr) != 0) { - pr_debug("Failed to get the address of line %d.\n", - lineno); - continue; - } - if (sp_die) { - /* Address filtering 1: does sp_die include addr? */ - if (!dwarf_haspc(sp_die, addr)) - continue; - /* Address filtering 2: No child include addr? */ - if (die_find_inlinefunc(sp_die, addr, &die_mem)) - continue; - } + /* + * Continue if no error, because the lazy pattern will match + * to other lines + */ + return ret < 0 ? ret : 0; +} - pr_debug("Probe line found: line[%d]:%d addr:0x%llx\n", - (int)i, lineno, (unsigned long long)addr); - pf->addr = addr; +/* Find probe points from lazy pattern */ +static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf) +{ + int ret = 0; - ret = convert_probe_point(sp_die, pf); - /* Continuing, because target line might be inlined. */ + if (intlist__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; } - /* TODO: deallocate lines, but how? */ - return ret; -} -/* Callback parameter with return value */ -struct dwarf_callback_param { - void *data; - int retval; -}; + return die_walk_lines(sp_die, probe_point_lazy_walker, pf); +} 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 pc of %s.\n", + 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 = convert_probe_point(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) { @@ -1016,10 +896,14 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data) struct perf_probe_point *pp = &pf->pev->point; /* Check tag and diename */ - if (dwarf_tag(sp_die) != DW_TAG_subprogram || + if (!die_is_func_def(sp_die) || !die_compare_name(sp_die, pp->function)) 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); @@ -1031,23 +915,19 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data) param->retval = find_probe_point_lazy(sp_die, pf); else { if (dwarf_entrypc(sp_die, &pf->addr) != 0) { - pr_warning("Failed to get entry pc of %s.\n", - dwarf_diename(sp_die)); + 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 = convert_probe_point(sp_die, pf); + 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. */ } @@ -1060,155 +940,489 @@ static int find_probe_point_by_func(struct probe_finder *pf) return _param.retval; } -/* 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) +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 probe_finder pf = {.pev = pev, .max_tevs = max_tevs}; - struct perf_probe_point *pp = &pev->point; + 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 *dbg, + struct probe_finder *pf) +{ + struct perf_probe_point *pp = &pf->pev->point; Dwarf_Off off, noff; size_t cuhl; Dwarf_Die *diep; - Dwarf *dbg; int ret = 0; - pf.tevs = zalloc(sizeof(struct probe_trace_event) * max_tevs); - if (pf.tevs == NULL) - return -ENOMEM; - *tevs = pf.tevs; - pf.ntevs = 0; - - dbg = dwarf_begin(fd, DWARF_C_READ); - if (!dbg) { - pr_warning("No dwarf info found in the vmlinux - " - "please rebuild with CONFIG_DEBUG_INFO=y.\n"); - free(pf.tevs); - *tevs = NULL; - return -EBADF; - } - #if _ELFUTILS_PREREQ(0, 142) /* Get the call frame information from this dwarf */ - pf.cfi = dwarf_getcfi(dbg); + pf->cfi = dwarf_getcfi_elf(dwarf_getelf(dbg->dbg)); #endif off = 0; - line_list__init(&pf.lcache); + pf->lcache = intlist__new(NULL); + if (!pf->lcache) + return -ENOMEM; + + /* 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(dbg->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(dbg, off, &noff, &cuhl, NULL, NULL, NULL) && - ret >= 0) { + while (!dwarf_nextcu(dbg->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(dbg->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); + pf->fname = cu_find_realpath(&pf->cu_die, pp->file); else - pf.fname = NULL; + pf->fname = NULL; - if (!pp->file || pf.fname) { + if (!pp->file || pf->fname) { if (pp->function) - ret = find_probe_point_by_func(&pf); + ret = find_probe_point_by_func(pf); else if (pp->lazy_line) - ret = find_probe_point_lazy(NULL, &pf); + ret = find_probe_point_lazy(NULL, pf); else { - pf.lno = pp->line; - ret = find_probe_point_by_line(&pf); + pf->lno = pp->line; + ret = find_probe_point_by_line(pf); } + if (ret < 0) + break; } off = noff; } - line_list__free(&pf.lcache); - dwarf_end(dbg); - return (ret < 0) ? ret : pf.ntevs; +found: + intlist__delete(pf->lcache); + pf->lcache = NULL; + + return ret; +} + +struct local_vars_finder { + struct probe_finder *pf; + struct perf_probe_arg *args; + int max_args; + int nargs; + int ret; +}; + +/* Collect available variables in this scope */ +static int copy_variables_cb(Dwarf_Die *die_mem, void *data) +{ + struct local_vars_finder *vf = data; + struct probe_finder *pf = vf->pf; + int tag; + + tag = dwarf_tag(die_mem); + if (tag == DW_TAG_formal_parameter || + tag == DW_TAG_variable) { + if (convert_variable_location(die_mem, vf->pf->addr, + vf->pf->fb_ops, &pf->sp_die, + NULL) == 0) { + vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem); + if (vf->args[vf->nargs].var == NULL) { + vf->ret = -ENOMEM; + return DIE_FIND_CB_END; + } + pr_debug(" %s", vf->args[vf->nargs].var); + vf->nargs++; + } + } + + if (dwarf_haspc(die_mem, vf->pf->addr)) + return DIE_FIND_CB_CONTINUE; + else + return DIE_FIND_CB_SIBLING; +} + +static int expand_probe_args(Dwarf_Die *sc_die, struct probe_finder *pf, + struct perf_probe_arg *args) +{ + Dwarf_Die die_mem; + int i; + int n = 0; + struct local_vars_finder vf = {.pf = pf, .args = args, + .max_args = MAX_PROBE_ARGS, .ret = 0}; + + for (i = 0; i < pf->pev->nargs; i++) { + /* var never be NULL */ + if (strcmp(pf->pev->args[i].var, "$vars") == 0) { + pr_debug("Expanding $vars into:"); + vf.nargs = n; + /* Special local variables */ + die_find_child(sc_die, copy_variables_cb, (void *)&vf, + &die_mem); + pr_debug(" (%d)\n", vf.nargs - n); + if (vf.ret < 0) + return vf.ret; + n = vf.nargs; + } else { + /* Copy normal argument */ + args[n] = pf->pev->args[i]; + n++; + } + } + return n; +} + +/* 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; + struct perf_probe_arg *args; + 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, tf->mod, 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); + + /* Expand special probe argument if exist */ + args = zalloc(sizeof(struct perf_probe_arg) * MAX_PROBE_ARGS); + if (args == NULL) + return -ENOMEM; + + ret = expand_probe_args(sc_die, pf, args); + if (ret < 0) + goto end; + + tev->nargs = ret; + tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); + if (tev->args == NULL) { + ret = -ENOMEM; + goto end; + } + + /* Find each argument */ + for (i = 0; i < tev->nargs; i++) { + pf->pvar = &args[i]; + pf->tvar = &tev->args[i]; + /* Variable should be found from scope DIE */ + ret = find_variable(sc_die, pf); + if (ret != 0) + break; + } + +end: + free(args); + return ret; +} + +/* Find probe_trace_events specified by perf_probe_event from debuginfo */ +int debuginfo__find_trace_events(struct debuginfo *dbg, + 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}, + .mod = dbg->mod, .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(dbg, &tf.pf); + if (ret < 0) { + zfree(tevs); + 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, &af->pf.sp_die, + 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, af->mod, 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 + * Return the number of found probe points. Return 0 if there is no + * matched probe point. Return <0 if an error occurs. + */ +int debuginfo__find_available_vars_at(struct debuginfo *dbg, + 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}, + .mod = dbg->mod, + .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(dbg, &af.pf); + if (ret < 0) { + /* Free vlist for error */ + while (af.nvls--) { + zfree(&af.vls[af.nvls].point.symbol); + strlist__delete(af.vls[af.nvls].vars); + } + zfree(vls); + return ret; + } + + return (ret < 0) ? ret : af.nvls; } /* Reverse search */ -int find_perf_probe_point(int fd, unsigned long addr, - struct perf_probe_point *ppt) +int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr, + struct perf_probe_point *ppt) { Dwarf_Die cudie, spdie, indie; - Dwarf *dbg; - Dwarf_Line *line; - Dwarf_Addr laddr, eaddr; - const char *tmp; - int lineno, ret = 0; - bool found = false; - - dbg = dwarf_begin(fd, DWARF_C_READ); - if (!dbg) - return -EBADF; + Dwarf_Addr _addr = 0, baseaddr = 0; + const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp; + int baseline = 0, lineno = 0, ret = 0; + + /* Adjust address with bias */ + addr += dbg->bias; /* Find cu die */ - if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie)) { + if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr - dbg->bias, &cudie)) { + pr_warning("Failed to find debug information for address %lx\n", + addr); ret = -EINVAL; goto end; } - /* Find a corresponding line */ - line = dwarf_getsrc_die(&cudie, (Dwarf_Addr)addr); - if (line) { - if (dwarf_lineaddr(line, &laddr) == 0 && - (Dwarf_Addr)addr == laddr && - dwarf_lineno(line, &lineno) == 0) { - tmp = dwarf_linesrc(line, NULL, NULL); - if (tmp) { - ppt->line = lineno; - ppt->file = strdup(tmp); - if (ppt->file == NULL) { - ret = -ENOMEM; - goto end; - } - found = true; - } + /* 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 */ + func = basefunc = dwarf_diename(&spdie); + if (!func || + dwarf_entrypc(&spdie, &baseaddr) != 0 || + dwarf_decl_line(&spdie, &baseline) != 0) { + lineno = 0; + goto post; } - } - /* Find a corresponding function */ - if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) { - tmp = dwarf_diename(&spdie); - if (!tmp || dwarf_entrypc(&spdie, &eaddr) != 0) - goto end; + fname = dwarf_decl_file(&spdie); + if (addr == (unsigned long)baseaddr) { + /* Function entry - Relative line number is 0 */ + lineno = baseline; + goto post; + } - if (ppt->line) { - if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr, + /* Track down the inline functions step by step */ + while (die_find_top_inlinefunc(&spdie, (Dwarf_Addr)addr, &indie)) { - /* addr in an inline function */ - tmp = dwarf_diename(&indie); - if (!tmp) - goto end; - ret = dwarf_decl_line(&indie, &lineno); + /* There is an inline function */ + 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. (overwrite lineinfo) + */ + lineno = die_get_call_lineno(&indie); + fname = die_get_call_file(&indie); + break; } else { - if (eaddr == addr) { /* Function entry */ - lineno = ppt->line; - ret = 0; - } else - ret = dwarf_decl_line(&spdie, &lineno); - } - if (ret == 0) { - /* Make a relative line number */ - ppt->line -= lineno; - goto found; + /* + * 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(&indie, &baseline) != 0) + break; + func = tmp; + spdie = indie; } } - /* We don't have a line number, let's use offset */ - ppt->offset = addr - (unsigned long)eaddr; -found: - ppt->function = strdup(tmp); + /* Verify the lineno and baseline are in a same file */ + tmp = dwarf_decl_file(&spdie); + if (!tmp || strcmp(tmp, fname) != 0) + lineno = 0; + } + +post: + /* Make a relative line number or an offset */ + if (lineno) + ppt->line = lineno - baseline; + else if (basefunc) { + ppt->offset = addr - (unsigned long)baseaddr; + func = basefunc; + } + + /* Duplicate strings */ + if (func) { + ppt->function = strdup(func); if (ppt->function == NULL) { ret = -ENOMEM; goto end; } - found = true; } - + if (fname) { + ppt->file = strdup(fname); + if (ppt->file == NULL) { + zfree(&ppt->function); + ret = -ENOMEM; + goto end; + } + } end: - dwarf_end(dbg); - if (ret >= 0) - ret = found ? 1 : 0; + if (ret == 0 && (fname || func)) + ret = 1; /* Found a point */ return ret; } @@ -1222,124 +1436,71 @@ static int line_range_add_line(const char *src, unsigned int lineno, if (lr->path == NULL) return -ENOMEM; } - return line_list__add_line(&lr->line_list, lineno); + return intlist__add(lr->line_list, lineno); } -/* Search function declaration lines */ -static int line_range_funcdecl_cb(Dwarf_Die *sp_die, void *data) +static int line_range_walk_cb(const char *fname, int lineno, + Dwarf_Addr addr __maybe_unused, + void *data) { - struct dwarf_callback_param *param = data; - struct line_finder *lf = param->data; - const char *src; - int lineno; - - src = dwarf_decl_file(sp_die); - if (src && strtailcmp(src, lf->fname) != 0) - return DWARF_CB_OK; + struct line_finder *lf = data; + int err; - if (dwarf_decl_line(sp_die, &lineno) != 0 || + if ((strtailcmp(fname, lf->fname) != 0) || (lf->lno_s > lineno || lf->lno_e < lineno)) - return DWARF_CB_OK; + return 0; - param->retval = line_range_add_line(src, lineno, lf->lr); - if (param->retval < 0) - return DWARF_CB_ABORT; - return DWARF_CB_OK; -} + err = line_range_add_line(fname, lineno, lf->lr); + if (err < 0 && err != -EEXIST) + return err; -static int find_line_range_func_decl_lines(struct line_finder *lf) -{ - struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0}; - dwarf_getfuncs(&lf->cu_die, line_range_funcdecl_cb, ¶m, 0); - return param.retval; + return 0; } /* Find line range from its line number */ static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf) { - Dwarf_Lines *lines; - Dwarf_Line *line; - size_t nlines, i; - Dwarf_Addr addr; - int lineno, ret = 0; - const char *src; - Dwarf_Die die_mem; - - line_list__init(&lf->lr->line_list); - if (dwarf_getsrclines(&lf->cu_die, &lines, &nlines) != 0) { - pr_warning("No source lines found in this CU.\n"); - return -ENOENT; - } - - /* Search probable lines on lines list */ - for (i = 0; i < nlines; i++) { - line = dwarf_onesrcline(lines, i); - if (dwarf_lineno(line, &lineno) != 0 || - (lf->lno_s > lineno || lf->lno_e < lineno)) - continue; - - if (sp_die) { - /* Address filtering 1: does sp_die include addr? */ - if (dwarf_lineaddr(line, &addr) != 0 || - !dwarf_haspc(sp_die, addr)) - continue; - - /* Address filtering 2: No child include addr? */ - if (die_find_inlinefunc(sp_die, addr, &die_mem)) - continue; - } - - /* TODO: Get fileno from line, but how? */ - src = dwarf_linesrc(line, NULL, NULL); - if (strtailcmp(src, lf->fname) != 0) - continue; - - ret = line_range_add_line(src, lineno, lf->lr); - if (ret < 0) - return ret; - } + int ret; - /* - * Dwarf lines doesn't include function declarations. We have to - * check functions list or given function. - */ - if (sp_die) { - src = dwarf_decl_file(sp_die); - if (src && dwarf_decl_line(sp_die, &lineno) == 0 && - (lf->lno_s <= lineno && lf->lno_e >= lineno)) - ret = line_range_add_line(src, lineno, lf->lr); - } else - ret = find_line_range_func_decl_lines(lf); + 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)) + if (!intlist__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; + zfree(&lf->lr->path); } return ret; } static int line_range_inline_cb(Dwarf_Die *in_die, void *data) { - struct dwarf_callback_param *param = data; + int ret = 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. However, if an error occurs, + * it should be handled by the caller. + */ + return ret < 0 ? ret : 0; } -/* Search function from function name */ +/* Search function definition 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; - if (dwarf_tag(sp_die) == DW_TAG_subprogram && + /* Check declared file */ + if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die))) + return DWARF_CB_OK; + + if (die_is_func_def(sp_die) && die_compare_name(sp_die, lr->function)) { lf->fname = dwarf_decl_file(sp_die); dwarf_decl_line(sp_die, &lr->offset); @@ -1353,15 +1514,10 @@ 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; } @@ -1375,30 +1531,40 @@ 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 *dbg, 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; const char *comp_dir; - dbg = dwarf_begin(fd, DWARF_C_READ); - if (!dbg) { - pr_warning("No dwarf info found in the vmlinux - " - "please rebuild with CONFIG_DEBUG_INFO=y.\n"); - return -EBADF; + /* 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(dbg->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(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 0) + if (dwarf_nextcu(dbg->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(dbg->dbg, off + cuhl, &lf.cu_die); if (!diep) continue; @@ -1420,6 +1586,7 @@ int find_line_range(int fd, struct line_range *lr) off = noff; } +found: /* Store comp_dir */ if (lf.found) { comp_dir = cu_get_comp_dir(&lf.cu_die); @@ -1431,8 +1598,6 @@ int find_line_range(int fd, struct line_range *lr) } pr_debug("path: %s\n", lr->path); - dwarf_end(dbg); - return (ret < 0) ? ret : lf.found; } |
