diff options
| -rw-r--r-- | tools/perf/Makefile | 2 | ||||
| -rw-r--r-- | tools/perf/arch/x86/Makefile | 3 | ||||
| -rw-r--r-- | tools/perf/arch/x86/util/unwind.c | 111 | ||||
| -rw-r--r-- | tools/perf/builtin-report.c | 18 | ||||
| -rw-r--r-- | tools/perf/builtin-script.c | 4 | ||||
| -rw-r--r-- | tools/perf/builtin-top.c | 6 | ||||
| -rw-r--r-- | tools/perf/util/include/linux/compiler.h | 1 | ||||
| -rw-r--r-- | tools/perf/util/map.h | 5 | ||||
| -rw-r--r-- | tools/perf/util/session.c | 66 | ||||
| -rw-r--r-- | tools/perf/util/session.h | 6 | ||||
| -rw-r--r-- | tools/perf/util/trace-event.h | 2 | ||||
| -rw-r--r-- | tools/perf/util/unwind.c | 567 | ||||
| -rw-r--r-- | tools/perf/util/unwind.h | 34 |
13 files changed, 795 insertions, 30 deletions
diff --git a/tools/perf/Makefile b/tools/perf/Makefile index 0aee6a916493..e457afa04b59 100644 --- a/tools/perf/Makefile +++ b/tools/perf/Makefile @@ -334,6 +334,7 @@ LIB_H += util/target.h LIB_H += util/rblist.h LIB_H += util/intlist.h LIB_H += util/perf_regs.h +LIB_H += util/unwind.h LIB_OBJS += $(OUTPUT)util/abspath.o LIB_OBJS += $(OUTPUT)util/alias.o @@ -547,6 +548,7 @@ else EXTLIBS += $(LIBUNWIND_LIBS) BASIC_CFLAGS := $(LIBUNWIND_CFLAGS) $(BASIC_CFLAGS) BASIC_LDFLAGS := $(LIBUNWIND_LDFLAGS) $(BASIC_LDFLAGS) + LIB_OBJS += $(OUTPUT)util/unwind.o endif ifdef NO_NEWT diff --git a/tools/perf/arch/x86/Makefile b/tools/perf/arch/x86/Makefile index 744e629797be..815841c04eb2 100644 --- a/tools/perf/arch/x86/Makefile +++ b/tools/perf/arch/x86/Makefile @@ -2,4 +2,7 @@ ifndef NO_DWARF PERF_HAVE_DWARF_REGS := 1 LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/dwarf-regs.o endif +ifndef NO_LIBUNWIND +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/unwind.o +endif LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/header.o diff --git a/tools/perf/arch/x86/util/unwind.c b/tools/perf/arch/x86/util/unwind.c new file mode 100644 index 000000000000..78d956eff96f --- /dev/null +++ b/tools/perf/arch/x86/util/unwind.c @@ -0,0 +1,111 @@ + +#include <errno.h> +#include <libunwind.h> +#include "perf_regs.h" +#include "../../util/unwind.h" + +#ifdef ARCH_X86_64 +int unwind__arch_reg_id(int regnum) +{ + int id; + + switch (regnum) { + case UNW_X86_64_RAX: + id = PERF_REG_X86_AX; + break; + case UNW_X86_64_RDX: + id = PERF_REG_X86_DX; + break; + case UNW_X86_64_RCX: + id = PERF_REG_X86_CX; + break; + case UNW_X86_64_RBX: + id = PERF_REG_X86_BX; + break; + case UNW_X86_64_RSI: + id = PERF_REG_X86_SI; + break; + case UNW_X86_64_RDI: + id = PERF_REG_X86_DI; + break; + case UNW_X86_64_RBP: + id = PERF_REG_X86_BP; + break; + case UNW_X86_64_RSP: + id = PERF_REG_X86_SP; + break; + case UNW_X86_64_R8: + id = PERF_REG_X86_R8; + break; + case UNW_X86_64_R9: + id = PERF_REG_X86_R9; + break; + case UNW_X86_64_R10: + id = PERF_REG_X86_R10; + break; + case UNW_X86_64_R11: + id = PERF_REG_X86_R11; + break; + case UNW_X86_64_R12: + id = PERF_REG_X86_R12; + break; + case UNW_X86_64_R13: + id = PERF_REG_X86_R13; + break; + case UNW_X86_64_R14: + id = PERF_REG_X86_R14; + break; + case UNW_X86_64_R15: + id = PERF_REG_X86_R15; + break; + case UNW_X86_64_RIP: + id = PERF_REG_X86_IP; + break; + default: + pr_err("unwind: invalid reg id %d\n", regnum); + return -EINVAL; + } + + return id; +} +#else +int unwind__arch_reg_id(int regnum) +{ + int id; + + switch (regnum) { + case UNW_X86_EAX: + id = PERF_REG_X86_AX; + break; + case UNW_X86_EDX: + id = PERF_REG_X86_DX; + break; + case UNW_X86_ECX: + id = PERF_REG_X86_CX; + break; + case UNW_X86_EBX: + id = PERF_REG_X86_BX; + break; + case UNW_X86_ESI: + id = PERF_REG_X86_SI; + break; + case UNW_X86_EDI: + id = PERF_REG_X86_DI; + break; + case UNW_X86_EBP: + id = PERF_REG_X86_BP; + break; + case UNW_X86_ESP: + id = PERF_REG_X86_SP; + break; + case UNW_X86_EIP: + id = PERF_REG_X86_IP; + break; + default: + pr_err("unwind: invalid reg id %d\n", regnum); + return -EINVAL; + } + + return id; +} +#endif /* ARCH_X86_64 */ diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 7c88a243b5db..d61825371adc 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -69,8 +69,8 @@ static int perf_report__add_branch_hist_entry(struct perf_tool *tool, if ((sort__has_parent || symbol_conf.use_callchain) && sample->callchain) { - err = machine__resolve_callchain(machine, al->thread, - sample->callchain, &parent); + err = machine__resolve_callchain(machine, evsel, al->thread, + sample, &parent); if (err) return err; } @@ -140,8 +140,8 @@ static int perf_evsel__add_hist_entry(struct perf_evsel *evsel, struct hist_entry *he; if ((sort__has_parent || symbol_conf.use_callchain) && sample->callchain) { - err = machine__resolve_callchain(machine, al->thread, - sample->callchain, &parent); + err = machine__resolve_callchain(machine, evsel, al->thread, + sample, &parent); if (err) return err; } @@ -397,17 +397,17 @@ static int __cmd_report(struct perf_report *rep) desc); } - if (dump_trace) { - perf_session__fprintf_nr_events(session, stdout); - goto out_delete; - } - if (verbose > 3) perf_session__fprintf(session, stdout); if (verbose > 2) perf_session__fprintf_dsos(session, stdout); + if (dump_trace) { + perf_session__fprintf_nr_events(session, stdout); + goto out_delete; + } + nr_samples = 0; list_for_each_entry(pos, &session->evlist->entries, node) { struct hists *hists = &pos->hists; diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index 30a9cb8c9927..2d6e3b226aad 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -380,7 +380,7 @@ static void print_sample_bts(union perf_event *event, printf(" "); else printf("\n"); - perf_event__print_ip(event, sample, machine, + perf_evsel__print_ip(evsel, event, sample, machine, PRINT_FIELD(SYM), PRINT_FIELD(DSO), PRINT_FIELD(SYMOFFSET)); } @@ -422,7 +422,7 @@ static void process_event(union perf_event *event, struct perf_sample *sample, printf(" "); else printf("\n"); - perf_event__print_ip(event, sample, machine, + perf_evsel__print_ip(evsel, event, sample, machine, PRINT_FIELD(SYM), PRINT_FIELD(DSO), PRINT_FIELD(SYMOFFSET)); } diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 68cd61ef6ac5..e45a1ba61722 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -783,8 +783,10 @@ static void perf_event__process_sample(struct perf_tool *tool, if ((sort__has_parent || symbol_conf.use_callchain) && sample->callchain) { - err = machine__resolve_callchain(machine, al.thread, - sample->callchain, &parent); + err = machine__resolve_callchain(machine, evsel, + al.thread, sample, + &parent); + if (err) return; } diff --git a/tools/perf/util/include/linux/compiler.h b/tools/perf/util/include/linux/compiler.h index 547628e97f3d..2dc867128e46 100644 --- a/tools/perf/util/include/linux/compiler.h +++ b/tools/perf/util/include/linux/compiler.h @@ -10,5 +10,6 @@ #endif #define __used __attribute__((__unused__)) +#define __packed __attribute__((__packed__)) #endif diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h index 1e183d1ae581..c98ab1900608 100644 --- a/tools/perf/util/map.h +++ b/tools/perf/util/map.h @@ -158,9 +158,12 @@ int machine__init(struct machine *self, const char *root_dir, pid_t pid); void machine__exit(struct machine *self); void machine__delete(struct machine *self); +struct perf_evsel; +struct perf_sample; int machine__resolve_callchain(struct machine *machine, + struct perf_evsel *evsel, struct thread *thread, - struct ip_callchain *chain, + struct perf_sample *sample, struct symbol **parent); int maps__set_kallsyms_ref_reloc_sym(struct map **maps, const char *symbol_name, u64 addr); diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index c9ed7e3cf231..f7bb7ae328da 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -16,6 +16,7 @@ #include "cpumap.h" #include "event-parse.h" #include "perf_regs.h" +#include "unwind.h" static int perf_session__open(struct perf_session *self, bool force) { @@ -289,10 +290,11 @@ struct branch_info *machine__resolve_bstack(struct machine *self, return bi; } -int machine__resolve_callchain(struct machine *self, - struct thread *thread, - struct ip_callchain *chain, - struct symbol **parent) +static int machine__resolve_callchain_sample(struct machine *machine, + struct thread *thread, + struct ip_callchain *chain, + struct symbol **parent) + { u8 cpumode = PERF_RECORD_MISC_USER; unsigned int i; @@ -317,11 +319,14 @@ int machine__resolve_callchain(struct machine *self, if (ip >= PERF_CONTEXT_MAX) { switch (ip) { case PERF_CONTEXT_HV: - cpumode = PERF_RECORD_MISC_HYPERVISOR; break; + cpumode = PERF_RECORD_MISC_HYPERVISOR; + break; case PERF_CONTEXT_KERNEL: - cpumode = PERF_RECORD_MISC_KERNEL; break; + cpumode = PERF_RECORD_MISC_KERNEL; + break; case PERF_CONTEXT_USER: - cpumode = PERF_RECORD_MISC_USER; break; + cpumode = PERF_RECORD_MISC_USER; + break; default: pr_debug("invalid callchain context: " "%"PRId64"\n", (s64) ip); @@ -336,7 +341,7 @@ int machine__resolve_callchain(struct machine *self, } al.filtered = false; - thread__find_addr_location(thread, self, cpumode, + thread__find_addr_location(thread, machine, cpumode, MAP__FUNCTION, ip, &al, NULL); if (al.sym != NULL) { if (sort__has_parent && !*parent && @@ -355,6 +360,40 @@ int machine__resolve_callchain(struct machine *self, return 0; } +static int unwind_entry(struct unwind_entry *entry, void *arg) +{ + struct callchain_cursor *cursor = arg; + return callchain_cursor_append(cursor, entry->ip, + entry->map, entry->sym); +} + +int machine__resolve_callchain(struct machine *machine, + struct perf_evsel *evsel, + struct thread *thread, + struct perf_sample *sample, + struct symbol **parent) + +{ + int ret; + + callchain_cursor_reset(&callchain_cursor); + + ret = machine__resolve_callchain_sample(machine, thread, + sample->callchain, parent); + if (ret) + return ret; + + /* Can we do dwarf post unwind? */ + if (!((evsel->attr.sample_type & PERF_SAMPLE_REGS_USER) && + (evsel->attr.sample_type & PERF_SAMPLE_STACK_USER))) + return 0; + + return unwind__get_entries(unwind_entry, &callchain_cursor, machine, + thread, evsel->attr.sample_regs_user, + sample); + +} + static int process_event_synth_tracing_data_stub(union perf_event *event __used, struct perf_session *session __used) { @@ -1533,9 +1572,9 @@ struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session, return NULL; } -void perf_event__print_ip(union perf_event *event, struct perf_sample *sample, - struct machine *machine, int print_sym, - int print_dso, int print_symoffset) +void perf_evsel__print_ip(struct perf_evsel *evsel, union perf_event *event, + struct perf_sample *sample, struct machine *machine, + int print_sym, int print_dso, int print_symoffset) { struct addr_location al; struct callchain_cursor_node *node; @@ -1549,8 +1588,9 @@ void perf_event__print_ip(union perf_event *event, struct perf_sample *sample, if (symbol_conf.use_callchain && sample->callchain) { - if (machine__resolve_callchain(machine, al.thread, - sample->callchain, NULL) != 0) { + + if (machine__resolve_callchain(machine, evsel, al.thread, + sample, NULL) != 0) { if (verbose) error("Failed to resolve callchain. Skipping\n"); return; diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h index 1f7ec87db7d7..176a60902f56 100644 --- a/tools/perf/util/session.h +++ b/tools/perf/util/session.h @@ -129,9 +129,9 @@ size_t perf_session__fprintf_nr_events(struct perf_session *session, FILE *fp); struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session, unsigned int type); -void perf_event__print_ip(union perf_event *event, struct perf_sample *sample, - struct machine *machine, int print_sym, - int print_dso, int print_symoffset); +void perf_evsel__print_ip(struct perf_evsel *evsel, union perf_event *event, + struct perf_sample *sample, struct machine *machine, + int print_sym, int print_dso, int print_symoffset); int perf_session__cpu_bitmap(struct perf_session *session, const char *cpu_list, unsigned long *cpu_bitmap); diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h index 7575dfd26e58..a55fd37ffea1 100644 --- a/tools/perf/util/trace-event.h +++ b/tools/perf/util/trace-event.h @@ -77,6 +77,8 @@ void tracing_data_put(struct tracing_data *tdata); struct addr_location; +struct perf_session; + struct scripting_ops { const char *name; int (*start_script) (const char *script, int argc, const char **argv); diff --git a/tools/perf/util/unwind.c b/tools/perf/util/unwind.c new file mode 100644 index 000000000000..00a42aa8d5c1 --- /dev/null +++ b/tools/perf/util/unwind.c @@ -0,0 +1,567 @@ +/* + * Post mortem Dwarf CFI based unwinding on top of regs and stack dumps. + * + * Lots of this code have been borrowed or heavily inspired from parts of + * the libunwind 0.99 code which are (amongst other contributors I may have + * forgotten): + * + * Copyright (C) 2002-2007 Hewlett-Packard Co + * Contributed by David Mosberger-Tang <davidm@hpl.hp.com> + * + * And the bugs have been added by: + * + * Copyright (C) 2010, Frederic Weisbecker <fweisbec@gmail.com> + * Copyright (C) 2012, Jiri Olsa <jolsa@redhat.com> + * + */ + +#include <elf.h> +#include <gelf.h> +#include <fcntl.h> +#include <string.h> +#include <unistd.h> +#include <sys/mman.h> +#include <linux/list.h> +#include <libunwind.h> +#include <libunwind-ptrace.h> +#include "thread.h" +#include "session.h" +#include "perf_regs.h" +#include "unwind.h" +#include "util.h" + +extern int +UNW_OBJ(dwarf_search_unwind_table) (unw_addr_space_t as, + unw_word_t ip, + unw_dyn_info_t *di, + unw_proc_info_t *pi, + int need_unwind_info, void *arg); + +#define dwarf_search_unwind_table UNW_OBJ(dwarf_search_unwind_table) + +#define DW_EH_PE_FORMAT_MASK 0x0f /* format of the encoded value */ +#define DW_EH_PE_APPL_MASK 0x70 /* how the value is to be applied */ + +/* Pointer-encoding formats: */ +#define DW_EH_PE_omit 0xff +#define DW_EH_PE_ptr 0x00 /* pointer-sized unsigned value */ +#define DW_EH_PE_udata4 0x03 /* unsigned 32-bit value */ +#define DW_EH_PE_udata8 0x04 /* unsigned 64-bit value */ +#define DW_EH_PE_sdata4 0x0b /* signed 32-bit value */ +#define DW_EH_PE_sdata8 0x0c /* signed 64-bit value */ + +/* Pointer-encoding application: */ +#define DW_EH_PE_absptr 0x00 /* absolute value */ +#define DW_EH_PE_pcrel 0x10 /* rel. to addr. of encoded value */ + +/* + * The following are not documented by LSB v1.3, yet they are used by + * GCC, presumably they aren't documented by LSB since they aren't + * used on Linux: + */ +#define DW_EH_PE_funcrel 0x40 /* start-of-procedure-relative */ +#define DW_EH_PE_aligned 0x50 /* aligned pointer */ + +/* Flags intentionaly not handled, since they're not needed: + * #define DW_EH_PE_indirect 0x80 + * #define DW_EH_PE_uleb128 0x01 + * #define DW_EH_PE_udata2 0x02 + * #define DW_EH_PE_sleb128 0x09 + * #define DW_EH_PE_sdata2 0x0a + * #define DW_EH_PE_textrel 0x20 + * #define DW_EH_PE_datarel 0x30 + */ + +struct unwind_info { + struct perf_sample *sample; + struct machine *machine; + struct thread *thread; + u64 sample_uregs; +}; + +#define dw_read(ptr, type, end) ({ \ + type *__p = (type *) ptr; \ + type __v; \ + if ((__p + 1) > (type *) end) \ + return -EINVAL; \ + __v = *__p++; \ + ptr = (typeof(ptr)) __p; \ + __v; \ + }) + +static int __dw_read_encoded_value(u8 **p, u8 *end, u64 *val, + u8 encoding) +{ + u8 *cur = *p; + *val = 0; + + switch (encoding) { + case DW_EH_PE_omit: + *val = 0; + goto out; + case DW_EH_PE_ptr: + *val = dw_read(cur, unsigned long, end); + goto out; + default: + break; + } + + switch (encoding & DW_EH_PE_APPL_MASK) { + case DW_EH_PE_absptr: + break; + case DW_EH_PE_pcrel: + *val = (unsigned long) cur; + break; + default: + return -EINVAL; + } + + if ((encoding & 0x07) == 0x00) + encoding |= DW_EH_PE_udata4; + + switch (encoding & DW_EH_PE_FORMAT_MASK) { + case DW_EH_PE_sdata4: + *val += dw_read(cur, s32, end); + break; + case DW_EH_PE_udata4: + *val += dw_read(cur, u32, end); + break; + case DW_EH_PE_sdata8: + *val += dw_read(cur, s64, end); + break; + case DW_EH_PE_udata8: + *val += dw_read(cur, u64, end); + break; + default: + return -EINVAL; + } + + out: + *p = cur; + return 0; +} + +#define dw_read_encoded_value(ptr, end, enc) ({ \ + u64 __v; \ + if (__dw_read_encoded_value(&ptr, end, &__v, enc)) { \ + return -EINVAL; \ + } \ + __v; \ + }) + +static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, + GElf_Shdr *shp, const char *name) +{ + Elf_Scn *sec = NULL; + + while ((sec = elf_nextscn(elf, sec)) != NULL) { + char *str; + + gelf_getshdr(sec, shp); + str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name); + if (!strcmp(name, str)) + break; + } + + return sec; +} + +static u64 elf_section_offset(int fd, const char *name) +{ + Elf *elf; + GElf_Ehdr ehdr; + GElf_Shdr shdr; + u64 offset = 0; + + elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); + if (elf == NULL) + return 0; + + do { + if (gelf_getehdr(elf, &ehdr) == NULL) + break; + + if (!elf_section_by_name(elf, &ehdr, &shdr, name)) + break; + + offset = shdr.sh_offset; + } while (0); + + elf_end(elf); + return offset; +} + +struct table_entry { + u32 start_ip_offset; + u32 fde_offset; +}; + +struct eh_frame_hdr { + unsigned char version; + unsigned char eh_frame_ptr_enc; + unsigned char fde_count_enc; + unsigned char table_enc; + + /* + * The rest of the header is variable-length and consists of the + * following members: + * + * encoded_t eh_frame_ptr; + * encoded_t fde_count; + */ + + /* A single encoded pointer should not be more than 8 bytes. */ + u64 enc[2]; + + /* + * struct { + * encoded_t start_ip; + * encoded_t fde_addr; + * } binary_search_table[fde_count]; + */ + char data[0]; +} __packed; + +static int unwind_spec_ehframe(struct dso *dso, struct machine *machine, + u64 offset, u64 *table_data, u64 *segbase, + u64 *fde_count) +{ + struct eh_frame_hdr hdr; + u8 *enc = (u8 *) &hdr.enc; + u8 *end = (u8 *) &hdr.data; + ssize_t r; + + r = dso__data_read_offset(dso, machine, offset, + (u8 *) &hdr, sizeof(hdr)); + if (r != sizeof(hdr)) + return -EINVAL; + + /* We dont need eh_frame_ptr, just skip it. */ + dw_read_encoded_value(enc, end, hdr.eh_frame_ptr_enc); + + *fde_count = dw_read_encoded_value(enc, end, hdr.fde_count_enc); + *segbase = offset; + *table_data = (enc - (u8 *) &hdr) + offset; + return 0; +} + +static int read_unwind_spec(struct dso *dso, struct machine *machine, + u64 *table_data, u64 *segbase, u64 *fde_count) +{ + int ret = -EINVAL, fd; + u64 offset; + + fd = dso__data_fd(dso, machine); + if (fd < 0) + return -EINVAL; + + offset = elf_section_offset(fd, ".eh_frame_hdr"); + close(fd); + + if (offset) + ret = unwind_spec_ehframe(dso, machine, offset, + table_data, segbase, + fde_count); + + /* TODO .debug_frame check if eh_frame_hdr fails */ + return ret; +} + +static struct map *find_map(unw_word_t ip, struct unwind_info *ui) +{ + struct addr_location al; + + thread__find_addr_map(ui->thread, ui->machine, PERF_RECORD_MISC_USER, + MAP__FUNCTION, ip, &al); + return al.map; +} + +static int +find_proc_info(unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pi, + int need_unwind_info, void *arg) +{ + struct unwind_info *ui = arg; + struct map *map; + unw_dyn_info_t di; + u64 table_data, segbase, fde_count; + + map = find_map(ip, ui); + if (!map || !map->dso) + return -EINVAL; + + pr_debug("unwind: find_proc_info dso %s\n", map->dso->name); + + if (read_unwind_spec(map->dso, ui->machine, + &table_data, &segbase, &fde_count)) + return -EINVAL; + + memset(&di, 0, sizeof(di)); + di.format = UNW_INFO_FORMAT_REMOTE_TABLE; + di.start_ip = map->start; + di.end_ip = map->end; + di.u.rti.segbase = map->start + segbase; + di.u.rti.table_data = map->start + table_data; + di.u.rti.table_len = fde_count * sizeof(struct table_entry) + / sizeof(unw_word_t); + return dwarf_search_unwind_table(as, ip, &di, pi, + need_unwind_info, arg); +} + +static int access_fpreg(unw_addr_space_t __used as, unw_regnum_t __used num, + unw_fpreg_t __used *val, int __used __write, + void __used *arg) +{ + pr_err("unwind: access_fpreg unsupported\n"); + return -UNW_EINVAL; +} + +static int get_dyn_info_list_addr(unw_addr_space_t __used as, + unw_word_t __used *dil_addr, + void __used *arg) +{ + return -UNW_ENOINFO; +} + +static int resume(unw_addr_space_t __used as, unw_cursor_t __used *cu, + void __used *arg) +{ + pr_err("unwind: resume unsupported\n"); + return -UNW_EINVAL; +} + +static int +get_proc_name(unw_addr_space_t __used as, unw_word_t __used addr, + char __used *bufp, size_t __used buf_len, + unw_word_t __used *offp, void __used *arg) +{ + pr_err("unwind: get_proc_name unsupported\n"); + return -UNW_EINVAL; +} + +static int access_dso_mem(struct unwind_info *ui, unw_word_t addr, + unw_word_t *data) +{ + struct addr_location al; + ssize_t size; + + thread__find_addr_map(ui->thread, ui->machine, PERF_RECORD_MISC_USER, + MAP__FUNCTION, addr, &al); + if (!al.map) { + pr_debug("unwind: no map for %lx\n", (unsigned long)addr); + return -1; + } + + if (!al.map->dso) + return -1; + + size = dso__data_read_addr(al.map->dso, al.map, ui->machine, + addr, (u8 *) data, sizeof(*data)); + + return !(size == sizeof(*data)); +} + +static int reg_value(unw_word_t *valp, struct regs_dump *regs, int id, + u64 sample_regs) +{ + int i, idx = 0; + + if (!(sample_regs & (1 << id))) + return -EINVAL; + + for (i = 0; i < id; i++) { + if (sample_regs & (1 << i)) + idx++; + } + + *valp = regs->regs[idx]; + return 0; +} + +static int access_mem(unw_addr_space_t __used as, + unw_word_t addr, unw_word_t *valp, + int __write, void *arg) +{ + struct unwind_info *ui = arg; + struct stack_dump *stack = &ui->sample->user_stack; + unw_word_t start, end; + int offset; + int ret; + + /* Don't support write, probably not needed. */ + if (__write || !stack || !ui->sample->user_regs.regs) { + *valp = 0; + return 0; + } + + ret = reg_value(&start, &ui->sample->user_regs, PERF_REG_SP, + ui->sample_uregs); + if (ret) + return ret; + + end = start + stack->size; + + /* Check overflow. */ + if (addr + sizeof(unw_word_t) < addr) + return -EINVAL; + + if (addr < start || addr + sizeof(unw_word_t) >= end) { + ret = access_dso_mem(ui, addr, valp); + if (ret) { + pr_debug("unwind: access_mem %p not inside range %p-%p\n", + (void *)addr, (void *)start, (void *)end); + *valp = 0; + return ret; + } + return 0; + } + + offset = addr - start; + *valp = *(unw_word_t *)&stack->data[offset]; + pr_debug("unwind: access_mem addr %p, val %lx, offset %d\n", + (void *)addr, (unsigned long)*valp, offset); + return 0; +} + +static int access_reg(unw_addr_space_t __used as, + unw_regnum_t regnum, unw_word_t *valp, + int __write, void *arg) +{ + struct unwind_info *ui = arg; + int id, ret; + + /* Don't support write, I suspect we don't need it. */ + if (__write) { + pr_err("unwind: access_reg w %d\n", regnum); + return 0; + } + + if (!ui->sample->user_regs.regs) { + *valp = 0; + return 0; + } + + id = unwind__arch_reg_id(regnum); + if (id < 0) + return -EINVAL; + + ret = reg_value(valp, &ui->sample->user_regs, id, ui->sample_uregs); + if (ret) { + pr_err("unwind: can't read reg %d\n", regnum); + return ret; + } + + pr_debug("unwind: reg %d, val %lx\n", regnum, (unsigned long)*valp); + return 0; +} + +static void put_unwind_info(unw_addr_space_t __used as, + unw_proc_info_t *pi __used, + void *arg __used) +{ + pr_debug("unwind: put_unwind_info called\n"); +} + +static int entry(u64 ip, struct thread *thread, struct machine *machine, + unwind_entry_cb_t cb, void *arg) +{ + struct unwind_entry e; + struct addr_location al; + + thread__find_addr_location(thread, machine, + PERF_RECORD_MISC_USER, + MAP__FUNCTION, ip, &al, NULL); + + e.ip = ip; + e.map = al.map; + e.sym = al.sym; + + pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n", + al.sym ? al.sym->name : "''", + ip, + al.map ? al.map->map_ip(al.map, ip) : (u64) 0); + + return cb(&e, arg); +} + +static void display_error(int err) +{ + switch (err) { + case UNW_EINVAL: + pr_err("unwind: Only supports local.\n"); + break; + case UNW_EUNSPEC: + pr_err("unwind: Unspecified error.\n"); + break; + case UNW_EBADREG: + pr_err("unwind: Register unavailable.\n"); + break; + default: + break; + } +} + +static unw_accessors_t accessors = { + .find_proc_info = find_proc_info, + .put_unwind_info = put_unwind_info, + .get_dyn_info_list_addr = get_dyn_info_list_addr, + .access_mem = access_mem, + .access_reg = access_reg, + .access_fpreg = access_fpreg, + .resume = resume, + .get_proc_name = get_proc_name, +}; + +static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb, + void *arg) +{ + unw_addr_space_t addr_space; + unw_cursor_t c; + int ret; + + addr_space = unw_create_addr_space(&accessors, 0); + if (!addr_space) { + pr_err("unwind: Can't create unwind address space.\n"); + return -ENOMEM; + } + + ret = unw_init_remote(&c, addr_space, ui); + if (ret) + display_error(ret); + + while (!ret && (unw_step(&c) > 0)) { + unw_word_t ip; + + unw_get_reg(&c, UNW_REG_IP, &ip); + ret = entry(ip, ui->thread, ui->machine, cb, arg); + } + + unw_destroy_addr_space(addr_space); + return ret; +} + +int unwind__get_entries(unwind_entry_cb_t cb, void *arg, + struct machine *machine, struct thread *thread, + u64 sample_uregs, struct perf_sample *data) +{ + unw_word_t ip; + struct unwind_info ui = { + .sample = data, + .sample_uregs = sample_uregs, + .thread = thread, + .machine = machine, + }; + int ret; + + if (!data->user_regs.regs) + return -EINVAL; + + ret = reg_value(&ip, &data->user_regs, PERF_REG_IP, sample_uregs); + if (ret) + return ret; + + ret = entry(ip, thread, machine, cb, arg); + if (ret) + return -ENOMEM; + + return get_entries(&ui, cb, arg); +} diff --git a/tools/perf/util/unwind.h b/tools/perf/util/unwind.h new file mode 100644 index 000000000000..919bd6ad8501 --- /dev/null +++ b/tools/perf/util/unwind.h @@ -0,0 +1,34 @@ +#ifndef __UNWIND_H +#define __UNWIND_H + +#include "types.h" +#include "event.h" +#include "symbol.h" + +struct unwind_entry { + struct map *map; + struct symbol *sym; + u64 ip; +}; + +typedef int (*unwind_entry_cb_t)(struct unwind_entry *entry, void *arg); + +#ifndef NO_LIBUNWIND_SUPPORT +int unwind__get_entries(unwind_entry_cb_t cb, void *arg, + struct machine *machine, + struct thread *thread, + u64 sample_uregs, + struct perf_sample *data); +int unwind__arch_reg_id(int regnum); +#else +static inline int +unwind__get_entries(unwind_entry_cb_t cb __used, void *arg __used, + struct machine *machine __used, + struct thread *thread __used, + u64 sample_uregs __used, + struct perf_sample *data __used) +{ + return 0; +} +#endif /* NO_LIBUNWIND_SUPPORT */ +#endif /* __UNWIND_H */ |