From b4b7ff4b08e691656c9d77c758fc355833128ac0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 20 Jan 2016 14:01:31 -0300 Subject: Linux-libre 4.4-gnu --- tools/perf/util/probe-finder.c | 82 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 71 insertions(+), 11 deletions(-) (limited to 'tools/perf/util/probe-finder.c') diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 29c43c068..05012bb17 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -70,6 +70,7 @@ static int debuginfo__init_offline_dwarf(struct debuginfo *dbg, if (!dbg->dwfl) goto error; + dwfl_report_begin(dbg->dwfl); dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd); if (!dbg->mod) goto error; @@ -78,6 +79,8 @@ static int debuginfo__init_offline_dwarf(struct debuginfo *dbg, if (!dbg->dbg) goto error; + dwfl_report_end(dbg->dwfl, NULL, NULL); + return 0; error: if (dbg->dwfl) @@ -591,6 +594,7 @@ static int find_variable(Dwarf_Die *sc_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, + const char *function, struct probe_trace_point *tp) { Dwarf_Addr eaddr, highaddr; @@ -634,8 +638,10 @@ static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod, /* 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"); + pr_warning("Failed to find \"%s%%return\",\n" + " because %s is an inlined function and" + " has no return point.\n", function, + function); return -EINVAL; } tp->retprobe = true; @@ -1175,8 +1181,9 @@ 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 perf_probe_point *pp = &pf->pev->point; struct probe_trace_event *tev; - struct perf_probe_arg *args; + struct perf_probe_arg *args = NULL; int ret, i; /* Check number of tevs */ @@ -1189,21 +1196,25 @@ static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf) /* 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); + pp->retprobe, pp->function, &tev->point); if (ret < 0) - return ret; + goto end; tev->point.realname = strdup(dwarf_diename(sc_die)); - if (!tev->point.realname) - return -ENOMEM; + if (!tev->point.realname) { + ret = -ENOMEM; + goto end; + } 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; + if (args == NULL) { + ret = -ENOMEM; + goto end; + } ret = expand_probe_args(sc_die, pf, args); if (ret < 0) @@ -1227,6 +1238,10 @@ static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf) } end: + if (ret) { + clear_probe_trace_event(tev); + tf->ntevs--; + } free(args); return ret; } @@ -1239,7 +1254,7 @@ int debuginfo__find_trace_events(struct debuginfo *dbg, struct trace_event_finder tf = { .pf = {.pev = pev, .callback = add_probe_trace_event}, .max_tevs = probe_conf.max_probes, .mod = dbg->mod}; - int ret; + int ret, i; /* Allocate result tevs array */ *tevs = zalloc(sizeof(struct probe_trace_event) * tf.max_tevs); @@ -1251,6 +1266,8 @@ int debuginfo__find_trace_events(struct debuginfo *dbg, ret = debuginfo__find_probes(dbg, &tf.pf); if (ret < 0) { + for (i = 0; i < tf.ntevs; i++) + clear_probe_trace_event(&tf.tevs[i]); zfree(tevs); return ret; } @@ -1319,6 +1336,7 @@ 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 perf_probe_point *pp = &pf->pev->point; struct variable_list *vl; Dwarf_Die die_mem; int ret; @@ -1332,7 +1350,7 @@ static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf) /* 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); + pp->retprobe, pp->function, &vl->point); if (ret < 0) return ret; @@ -1399,6 +1417,41 @@ int debuginfo__find_available_vars_at(struct debuginfo *dbg, return (ret < 0) ? ret : af.nvls; } +/* For the kernel module, we need a special code to get a DIE */ +static int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs) +{ + int n, i; + Elf32_Word shndx; + Elf_Scn *scn; + Elf *elf; + GElf_Shdr mem, *shdr; + const char *p; + + elf = dwfl_module_getelf(dbg->mod, &dbg->bias); + if (!elf) + return -EINVAL; + + /* Get the number of relocations */ + n = dwfl_module_relocations(dbg->mod); + if (n < 0) + return -ENOENT; + /* Search the relocation related .text section */ + for (i = 0; i < n; i++) { + p = dwfl_module_relocation_info(dbg->mod, i, &shndx); + if (strcmp(p, ".text") == 0) { + /* OK, get the section header */ + scn = elf_getscn(elf, shndx); + if (!scn) + return -ENOENT; + shdr = gelf_getshdr(scn, &mem); + if (!shdr) + return -ENOENT; + *offs = shdr->sh_addr; + } + } + return 0; +} + /* Reverse search */ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr, struct perf_probe_point *ppt) @@ -1407,9 +1460,16 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr, Dwarf_Addr _addr = 0, baseaddr = 0; const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp; int baseline = 0, lineno = 0, ret = 0; + bool reloc = false; +retry: /* Find cu die */ if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr, &cudie)) { + if (!reloc && debuginfo__get_text_offset(dbg, &baseaddr) == 0) { + addr += baseaddr; + reloc = true; + goto retry; + } pr_warning("Failed to find debug information for address %lx\n", addr); ret = -EINVAL; -- cgit v1.2.3-54-g00ecf