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-rw-r--r--tools/perf/util/jitdump.c793
1 files changed, 793 insertions, 0 deletions
diff --git a/tools/perf/util/jitdump.c b/tools/perf/util/jitdump.c
new file mode 100644
index 000000000..663e790c2
--- /dev/null
+++ b/tools/perf/util/jitdump.c
@@ -0,0 +1,793 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <sys/sysmacros.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <byteswap.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <linux/stringify.h>
+
+#include "util.h"
+#include "event.h"
+#include "debug.h"
+#include "evlist.h"
+#include "symbol.h"
+#include <elf.h>
+
+#include "tsc.h"
+#include "session.h"
+#include "jit.h"
+#include "jitdump.h"
+#include "genelf.h"
+#include "../builtin.h"
+
+#include "sane_ctype.h"
+
+struct jit_buf_desc {
+ struct perf_data *output;
+ struct perf_session *session;
+ struct machine *machine;
+ union jr_entry *entry;
+ void *buf;
+ uint64_t sample_type;
+ size_t bufsize;
+ FILE *in;
+ bool needs_bswap; /* handles cross-endianess */
+ bool use_arch_timestamp;
+ void *debug_data;
+ void *unwinding_data;
+ uint64_t unwinding_size;
+ uint64_t unwinding_mapped_size;
+ uint64_t eh_frame_hdr_size;
+ size_t nr_debug_entries;
+ uint32_t code_load_count;
+ u64 bytes_written;
+ struct rb_root code_root;
+ char dir[PATH_MAX];
+};
+
+struct debug_line_info {
+ unsigned long vma;
+ unsigned int lineno;
+ /* The filename format is unspecified, absolute path, relative etc. */
+ char const filename[0];
+};
+
+struct jit_tool {
+ struct perf_tool tool;
+ struct perf_data output;
+ struct perf_data input;
+ u64 bytes_written;
+};
+
+#define hmax(a, b) ((a) > (b) ? (a) : (b))
+#define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
+
+static int
+jit_emit_elf(char *filename,
+ const char *sym,
+ uint64_t code_addr,
+ const void *code,
+ int csize,
+ void *debug,
+ int nr_debug_entries,
+ void *unwinding,
+ uint32_t unwinding_header_size,
+ uint32_t unwinding_size)
+{
+ int ret, fd;
+
+ if (verbose > 0)
+ fprintf(stderr, "write ELF image %s\n", filename);
+
+ fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
+ if (fd == -1) {
+ pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(errno));
+ return -1;
+ }
+
+ ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize, debug, nr_debug_entries,
+ unwinding, unwinding_header_size, unwinding_size);
+
+ close(fd);
+
+ if (ret)
+ unlink(filename);
+
+ return ret;
+}
+
+static void
+jit_close(struct jit_buf_desc *jd)
+{
+ if (!(jd && jd->in))
+ return;
+ funlockfile(jd->in);
+ fclose(jd->in);
+ jd->in = NULL;
+}
+
+static int
+jit_validate_events(struct perf_session *session)
+{
+ struct perf_evsel *evsel;
+
+ /*
+ * check that all events use CLOCK_MONOTONIC
+ */
+ evlist__for_each_entry(session->evlist, evsel) {
+ if (evsel->attr.use_clockid == 0 || evsel->attr.clockid != CLOCK_MONOTONIC)
+ return -1;
+ }
+ return 0;
+}
+
+static int
+jit_open(struct jit_buf_desc *jd, const char *name)
+{
+ struct jitheader header;
+ struct jr_prefix *prefix;
+ ssize_t bs, bsz = 0;
+ void *n, *buf = NULL;
+ int ret, retval = -1;
+
+ jd->in = fopen(name, "r");
+ if (!jd->in)
+ return -1;
+
+ bsz = hmax(sizeof(header), sizeof(*prefix));
+
+ buf = malloc(bsz);
+ if (!buf)
+ goto error;
+
+ /*
+ * protect from writer modifying the file while we are reading it
+ */
+ flockfile(jd->in);
+
+ ret = fread(buf, sizeof(header), 1, jd->in);
+ if (ret != 1)
+ goto error;
+
+ memcpy(&header, buf, sizeof(header));
+
+ if (header.magic != JITHEADER_MAGIC) {
+ if (header.magic != JITHEADER_MAGIC_SW)
+ goto error;
+ jd->needs_bswap = true;
+ }
+
+ if (jd->needs_bswap) {
+ header.version = bswap_32(header.version);
+ header.total_size = bswap_32(header.total_size);
+ header.pid = bswap_32(header.pid);
+ header.elf_mach = bswap_32(header.elf_mach);
+ header.timestamp = bswap_64(header.timestamp);
+ header.flags = bswap_64(header.flags);
+ }
+
+ jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
+
+ if (verbose > 2)
+ pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
+ header.version,
+ header.total_size,
+ (unsigned long long)header.timestamp,
+ header.pid,
+ header.elf_mach,
+ jd->use_arch_timestamp);
+
+ if (header.version > JITHEADER_VERSION) {
+ pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
+ header.version);
+ goto error;
+ }
+
+ if (header.flags & JITDUMP_FLAGS_RESERVED) {
+ pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
+ (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
+ goto error;
+ }
+
+ if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
+ pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
+ goto error;
+ }
+
+ /*
+ * validate event is using the correct clockid
+ */
+ if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
+ pr_err("error, jitted code must be sampled with perf record -k 1\n");
+ goto error;
+ }
+
+ bs = header.total_size - sizeof(header);
+
+ if (bs > bsz) {
+ n = realloc(buf, bs);
+ if (!n)
+ goto error;
+ bsz = bs;
+ buf = n;
+ /* read extra we do not know about */
+ ret = fread(buf, bs - bsz, 1, jd->in);
+ if (ret != 1)
+ goto error;
+ }
+ /*
+ * keep dirname for generating files and mmap records
+ */
+ strcpy(jd->dir, name);
+ dirname(jd->dir);
+
+ return 0;
+error:
+ funlockfile(jd->in);
+ fclose(jd->in);
+ return retval;
+}
+
+static union jr_entry *
+jit_get_next_entry(struct jit_buf_desc *jd)
+{
+ struct jr_prefix *prefix;
+ union jr_entry *jr;
+ void *addr;
+ size_t bs, size;
+ int id, ret;
+
+ if (!(jd && jd->in))
+ return NULL;
+
+ if (jd->buf == NULL) {
+ size_t sz = getpagesize();
+ if (sz < sizeof(*prefix))
+ sz = sizeof(*prefix);
+
+ jd->buf = malloc(sz);
+ if (jd->buf == NULL)
+ return NULL;
+
+ jd->bufsize = sz;
+ }
+
+ prefix = jd->buf;
+
+ /*
+ * file is still locked at this point
+ */
+ ret = fread(prefix, sizeof(*prefix), 1, jd->in);
+ if (ret != 1)
+ return NULL;
+
+ if (jd->needs_bswap) {
+ prefix->id = bswap_32(prefix->id);
+ prefix->total_size = bswap_32(prefix->total_size);
+ prefix->timestamp = bswap_64(prefix->timestamp);
+ }
+ id = prefix->id;
+ size = prefix->total_size;
+
+ bs = (size_t)size;
+ if (bs < sizeof(*prefix))
+ return NULL;
+
+ if (id >= JIT_CODE_MAX) {
+ pr_warning("next_entry: unknown record type %d, skipping\n", id);
+ }
+ if (bs > jd->bufsize) {
+ void *n;
+ n = realloc(jd->buf, bs);
+ if (!n)
+ return NULL;
+ jd->buf = n;
+ jd->bufsize = bs;
+ }
+
+ addr = ((void *)jd->buf) + sizeof(*prefix);
+
+ ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
+ if (ret != 1)
+ return NULL;
+
+ jr = (union jr_entry *)jd->buf;
+
+ switch(id) {
+ case JIT_CODE_DEBUG_INFO:
+ if (jd->needs_bswap) {
+ uint64_t n;
+ jr->info.code_addr = bswap_64(jr->info.code_addr);
+ jr->info.nr_entry = bswap_64(jr->info.nr_entry);
+ for (n = 0 ; n < jr->info.nr_entry; n++) {
+ jr->info.entries[n].addr = bswap_64(jr->info.entries[n].addr);
+ jr->info.entries[n].lineno = bswap_32(jr->info.entries[n].lineno);
+ jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
+ }
+ }
+ break;
+ case JIT_CODE_UNWINDING_INFO:
+ if (jd->needs_bswap) {
+ jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
+ jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
+ jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
+ }
+ break;
+ case JIT_CODE_CLOSE:
+ break;
+ case JIT_CODE_LOAD:
+ if (jd->needs_bswap) {
+ jr->load.pid = bswap_32(jr->load.pid);
+ jr->load.tid = bswap_32(jr->load.tid);
+ jr->load.vma = bswap_64(jr->load.vma);
+ jr->load.code_addr = bswap_64(jr->load.code_addr);
+ jr->load.code_size = bswap_64(jr->load.code_size);
+ jr->load.code_index= bswap_64(jr->load.code_index);
+ }
+ jd->code_load_count++;
+ break;
+ case JIT_CODE_MOVE:
+ if (jd->needs_bswap) {
+ jr->move.pid = bswap_32(jr->move.pid);
+ jr->move.tid = bswap_32(jr->move.tid);
+ jr->move.vma = bswap_64(jr->move.vma);
+ jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
+ jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
+ jr->move.code_size = bswap_64(jr->move.code_size);
+ jr->move.code_index = bswap_64(jr->move.code_index);
+ }
+ break;
+ case JIT_CODE_MAX:
+ default:
+ /* skip unknown record (we have read them) */
+ break;
+ }
+ return jr;
+}
+
+static int
+jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
+{
+ ssize_t size;
+
+ size = perf_data__write(jd->output, event, event->header.size);
+ if (size < 0)
+ return -1;
+
+ jd->bytes_written += size;
+ return 0;
+}
+
+static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
+{
+ struct perf_tsc_conversion tc;
+
+ if (!jd->use_arch_timestamp)
+ return timestamp;
+
+ tc.time_shift = jd->session->time_conv.time_shift;
+ tc.time_mult = jd->session->time_conv.time_mult;
+ tc.time_zero = jd->session->time_conv.time_zero;
+
+ if (!tc.time_mult)
+ return 0;
+
+ return tsc_to_perf_time(timestamp, &tc);
+}
+
+static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+ struct perf_sample sample;
+ union perf_event *event;
+ struct perf_tool *tool = jd->session->tool;
+ uint64_t code, addr;
+ uintptr_t uaddr;
+ char *filename;
+ struct stat st;
+ size_t size;
+ u16 idr_size;
+ const char *sym;
+ uint64_t count;
+ int ret, csize, usize;
+ pid_t pid, tid;
+ struct {
+ u32 pid, tid;
+ u64 time;
+ } *id;
+
+ pid = jr->load.pid;
+ tid = jr->load.tid;
+ csize = jr->load.code_size;
+ usize = jd->unwinding_mapped_size;
+ addr = jr->load.code_addr;
+ sym = (void *)((unsigned long)jr + sizeof(jr->load));
+ code = (unsigned long)jr + jr->load.p.total_size - csize;
+ count = jr->load.code_index;
+ idr_size = jd->machine->id_hdr_size;
+
+ event = calloc(1, sizeof(*event) + idr_size);
+ if (!event)
+ return -1;
+
+ filename = event->mmap2.filename;
+ size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
+ jd->dir,
+ pid,
+ count);
+
+ size++; /* for \0 */
+
+ size = PERF_ALIGN(size, sizeof(u64));
+ uaddr = (uintptr_t)code;
+ ret = jit_emit_elf(filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
+ jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
+
+ if (jd->debug_data && jd->nr_debug_entries) {
+ free(jd->debug_data);
+ jd->debug_data = NULL;
+ jd->nr_debug_entries = 0;
+ }
+
+ if (jd->unwinding_data && jd->eh_frame_hdr_size) {
+ free(jd->unwinding_data);
+ jd->unwinding_data = NULL;
+ jd->eh_frame_hdr_size = 0;
+ jd->unwinding_mapped_size = 0;
+ jd->unwinding_size = 0;
+ }
+
+ if (ret) {
+ free(event);
+ return -1;
+ }
+ if (stat(filename, &st))
+ memset(&st, 0, sizeof(st));
+
+ event->mmap2.header.type = PERF_RECORD_MMAP2;
+ event->mmap2.header.misc = PERF_RECORD_MISC_USER;
+ event->mmap2.header.size = (sizeof(event->mmap2) -
+ (sizeof(event->mmap2.filename) - size) + idr_size);
+
+ event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
+ event->mmap2.start = addr;
+ event->mmap2.len = usize ? ALIGN_8(csize) + usize : csize;
+ event->mmap2.pid = pid;
+ event->mmap2.tid = tid;
+ event->mmap2.ino = st.st_ino;
+ event->mmap2.maj = major(st.st_dev);
+ event->mmap2.min = minor(st.st_dev);
+ event->mmap2.prot = st.st_mode;
+ event->mmap2.flags = MAP_SHARED;
+ event->mmap2.ino_generation = 1;
+
+ id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
+ if (jd->sample_type & PERF_SAMPLE_TID) {
+ id->pid = pid;
+ id->tid = tid;
+ }
+ if (jd->sample_type & PERF_SAMPLE_TIME)
+ id->time = convert_timestamp(jd, jr->load.p.timestamp);
+
+ /*
+ * create pseudo sample to induce dso hit increment
+ * use first address as sample address
+ */
+ memset(&sample, 0, sizeof(sample));
+ sample.cpumode = PERF_RECORD_MISC_USER;
+ sample.pid = pid;
+ sample.tid = tid;
+ sample.time = id->time;
+ sample.ip = addr;
+
+ ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
+ if (ret)
+ return ret;
+
+ ret = jit_inject_event(jd, event);
+ /*
+ * mark dso as use to generate buildid in the header
+ */
+ if (!ret)
+ build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
+
+ return ret;
+}
+
+static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+ struct perf_sample sample;
+ union perf_event *event;
+ struct perf_tool *tool = jd->session->tool;
+ char *filename;
+ size_t size;
+ struct stat st;
+ int usize;
+ u16 idr_size;
+ int ret;
+ pid_t pid, tid;
+ struct {
+ u32 pid, tid;
+ u64 time;
+ } *id;
+
+ pid = jr->move.pid;
+ tid = jr->move.tid;
+ usize = jd->unwinding_mapped_size;
+ idr_size = jd->machine->id_hdr_size;
+
+ /*
+ * +16 to account for sample_id_all (hack)
+ */
+ event = calloc(1, sizeof(*event) + 16);
+ if (!event)
+ return -1;
+
+ filename = event->mmap2.filename;
+ size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
+ jd->dir,
+ pid,
+ jr->move.code_index);
+
+ size++; /* for \0 */
+
+ if (stat(filename, &st))
+ memset(&st, 0, sizeof(st));
+
+ size = PERF_ALIGN(size, sizeof(u64));
+
+ event->mmap2.header.type = PERF_RECORD_MMAP2;
+ event->mmap2.header.misc = PERF_RECORD_MISC_USER;
+ event->mmap2.header.size = (sizeof(event->mmap2) -
+ (sizeof(event->mmap2.filename) - size) + idr_size);
+ event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
+ event->mmap2.start = jr->move.new_code_addr;
+ event->mmap2.len = usize ? ALIGN_8(jr->move.code_size) + usize
+ : jr->move.code_size;
+ event->mmap2.pid = pid;
+ event->mmap2.tid = tid;
+ event->mmap2.ino = st.st_ino;
+ event->mmap2.maj = major(st.st_dev);
+ event->mmap2.min = minor(st.st_dev);
+ event->mmap2.prot = st.st_mode;
+ event->mmap2.flags = MAP_SHARED;
+ event->mmap2.ino_generation = 1;
+
+ id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
+ if (jd->sample_type & PERF_SAMPLE_TID) {
+ id->pid = pid;
+ id->tid = tid;
+ }
+ if (jd->sample_type & PERF_SAMPLE_TIME)
+ id->time = convert_timestamp(jd, jr->load.p.timestamp);
+
+ /*
+ * create pseudo sample to induce dso hit increment
+ * use first address as sample address
+ */
+ memset(&sample, 0, sizeof(sample));
+ sample.cpumode = PERF_RECORD_MISC_USER;
+ sample.pid = pid;
+ sample.tid = tid;
+ sample.time = id->time;
+ sample.ip = jr->move.new_code_addr;
+
+ ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
+ if (ret)
+ return ret;
+
+ ret = jit_inject_event(jd, event);
+ if (!ret)
+ build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
+
+ return ret;
+}
+
+static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+ void *data;
+ size_t sz;
+
+ if (!(jd && jr))
+ return -1;
+
+ sz = jr->prefix.total_size - sizeof(jr->info);
+ data = malloc(sz);
+ if (!data)
+ return -1;
+
+ memcpy(data, &jr->info.entries, sz);
+
+ jd->debug_data = data;
+
+ /*
+ * we must use nr_entry instead of size here because
+ * we cannot distinguish actual entry from padding otherwise
+ */
+ jd->nr_debug_entries = jr->info.nr_entry;
+
+ return 0;
+}
+
+static int
+jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+ void *unwinding_data;
+ uint32_t unwinding_data_size;
+
+ if (!(jd && jr))
+ return -1;
+
+ unwinding_data_size = jr->prefix.total_size - sizeof(jr->unwinding);
+ unwinding_data = malloc(unwinding_data_size);
+ if (!unwinding_data)
+ return -1;
+
+ memcpy(unwinding_data, &jr->unwinding.unwinding_data,
+ unwinding_data_size);
+
+ jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
+ jd->unwinding_size = jr->unwinding.unwinding_size;
+ jd->unwinding_mapped_size = jr->unwinding.mapped_size;
+ jd->unwinding_data = unwinding_data;
+
+ return 0;
+}
+
+static int
+jit_process_dump(struct jit_buf_desc *jd)
+{
+ union jr_entry *jr;
+ int ret = 0;
+
+ while ((jr = jit_get_next_entry(jd))) {
+ switch(jr->prefix.id) {
+ case JIT_CODE_LOAD:
+ ret = jit_repipe_code_load(jd, jr);
+ break;
+ case JIT_CODE_MOVE:
+ ret = jit_repipe_code_move(jd, jr);
+ break;
+ case JIT_CODE_DEBUG_INFO:
+ ret = jit_repipe_debug_info(jd, jr);
+ break;
+ case JIT_CODE_UNWINDING_INFO:
+ ret = jit_repipe_unwinding_info(jd, jr);
+ break;
+ default:
+ ret = 0;
+ continue;
+ }
+ }
+ return ret;
+}
+
+static int
+jit_inject(struct jit_buf_desc *jd, char *path)
+{
+ int ret;
+
+ if (verbose > 0)
+ fprintf(stderr, "injecting: %s\n", path);
+
+ ret = jit_open(jd, path);
+ if (ret)
+ return -1;
+
+ ret = jit_process_dump(jd);
+
+ jit_close(jd);
+
+ if (verbose > 0)
+ fprintf(stderr, "injected: %s (%d)\n", path, ret);
+
+ return 0;
+}
+
+/*
+ * File must be with pattern .../jit-XXXX.dump
+ * where XXXX is the PID of the process which did the mmap()
+ * as captured in the RECORD_MMAP record
+ */
+static int
+jit_detect(char *mmap_name, pid_t pid)
+ {
+ char *p;
+ char *end = NULL;
+ pid_t pid2;
+
+ if (verbose > 2)
+ fprintf(stderr, "jit marker trying : %s\n", mmap_name);
+ /*
+ * get file name
+ */
+ p = strrchr(mmap_name, '/');
+ if (!p)
+ return -1;
+
+ /*
+ * match prefix
+ */
+ if (strncmp(p, "/jit-", 5))
+ return -1;
+
+ /*
+ * skip prefix
+ */
+ p += 5;
+
+ /*
+ * must be followed by a pid
+ */
+ if (!isdigit(*p))
+ return -1;
+
+ pid2 = (int)strtol(p, &end, 10);
+ if (!end)
+ return -1;
+
+ /*
+ * pid does not match mmap pid
+ * pid==0 in system-wide mode (synthesized)
+ */
+ if (pid && pid2 != pid)
+ return -1;
+ /*
+ * validate suffix
+ */
+ if (strcmp(end, ".dump"))
+ return -1;
+
+ if (verbose > 0)
+ fprintf(stderr, "jit marker found: %s\n", mmap_name);
+
+ return 0;
+}
+
+int
+jit_process(struct perf_session *session,
+ struct perf_data *output,
+ struct machine *machine,
+ char *filename,
+ pid_t pid,
+ u64 *nbytes)
+{
+ struct perf_evsel *first;
+ struct jit_buf_desc jd;
+ int ret;
+
+ /*
+ * first, detect marker mmap (i.e., the jitdump mmap)
+ */
+ if (jit_detect(filename, pid))
+ return 0;
+
+ memset(&jd, 0, sizeof(jd));
+
+ jd.session = session;
+ jd.output = output;
+ jd.machine = machine;
+
+ /*
+ * track sample_type to compute id_all layout
+ * perf sets the same sample type to all events as of now
+ */
+ first = perf_evlist__first(session->evlist);
+ jd.sample_type = first->attr.sample_type;
+
+ *nbytes = 0;
+
+ ret = jit_inject(&jd, filename);
+ if (!ret) {
+ *nbytes = jd.bytes_written;
+ ret = 1;
+ }
+
+ return ret;
+}