probe-event.c

Go to the documentation of this file.

/*
 * probe-event.c : perf-probe definition to probe_events format converter
 *
 * Written by Masami Hiramatsu <mhiramat@redhat.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 */

#include <inttypes.h>
#include <sys/utsname.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <limits.h>
#include <elf.h>

#include "util.h"
#include "event.h"
#include "strlist.h"
#include "strfilter.h"
#include "debug.h"
#include "cache.h"
#include "color.h"
#include "symbol.h"
#include "thread.h"
#include <api/fs/fs.h>
#include "trace-event.h"    /* For __maybe_unused */
#include "probe-event.h"
#include "probe-finder.h"
#include "probe-file.h"
#include "session.h"
#include "string2.h"

#include "sane_ctype.h"

#define PERFPROBE_GROUP "probe"

bool probe_event_dry_run;   /* Dry run flag */
struct probe_conf probe_conf;

#define semantic_error(msg ...) pr_err("Semantic error :" msg)

int e_snprintf(char *str, size_t size, const char *format, ...)
{
    int ret;
    va_list ap;
    va_start(ap, format);
    ret = vsnprintf(str, size, format, ap);
    va_end(ap);
    if (ret >= (int)size)
        ret = -E2BIG;
    return ret;
}

static struct machine *host_machine;

/* Initialize symbol maps and path of vmlinux/modules */
int init_probe_symbol_maps(bool user_only)
{
    int ret;

    symbol_conf.sort_by_name = true;
    symbol_conf.allow_aliases = true;
    ret = symbol__init(NULL);
    if (ret < 0) {
        pr_debug("Failed to init symbol map.\n");
        goto out;
    }

    if (host_machine || user_only)  /* already initialized */
        return 0;

    if (symbol_conf.vmlinux_name)
        pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);

    host_machine = machine__new_host();
    if (!host_machine) {
        pr_debug("machine__new_host() failed.\n");
        symbol__exit();
        ret = -1;
    }
out:
    if (ret < 0)
        pr_warning("Failed to init vmlinux path.\n");
    return ret;
}

void exit_probe_symbol_maps(void)
{
    machine__delete(host_machine);
    host_machine = NULL;
    symbol__exit();
}

static struct ref_reloc_sym *kernel_get_ref_reloc_sym(void)
{
    /* kmap->ref_reloc_sym should be set if host_machine is initialized */
    struct kmap *kmap;
    struct map *map = machine__kernel_map(host_machine);

    if (map__load(map) < 0)
        return NULL;

    kmap = map__kmap(map);
    if (!kmap)
        return NULL;
    return kmap->ref_reloc_sym;
}

static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
                         bool reloc, bool reladdr)
{
    struct ref_reloc_sym *reloc_sym;
    struct symbol *sym;
    struct map *map;

    /* ref_reloc_sym is just a label. Need a special fix*/
    reloc_sym = kernel_get_ref_reloc_sym();
    if (reloc_sym && strcmp(name, reloc_sym->name) == 0)
        *addr = (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr;
    else {
        sym = machine__find_kernel_symbol_by_name(host_machine, name, &map);
        if (!sym)
            return -ENOENT;
        *addr = map->unmap_ip(map, sym->start) -
            ((reloc) ? 0 : map->reloc) -
            ((reladdr) ? map->start : 0);
    }
    return 0;
}

static struct map *kernel_get_module_map(const char *module)
{
    struct maps *maps = machine__kernel_maps(host_machine);
    struct map *pos;

    /* A file path -- this is an offline module */
    if (module && strchr(module, '/'))
        return dso__new_map(module);

    if (!module)
        module = "kernel";

    for (pos = maps__first(maps); pos; pos = map__next(pos)) {
        /* short_name is "[module]" */
        if (strncmp(pos->dso->short_name + 1, module,
                pos->dso->short_name_len - 2) == 0 &&
            module[pos->dso->short_name_len - 2] == '\0') {
            return map__get(pos);
        }
    }
    return NULL;
}

struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user)
{
    /* Init maps of given executable or kernel */
    if (user) {
        struct map *map;

        map = dso__new_map(target);
        if (map && map->dso)
            map->dso->nsinfo = nsinfo__get(nsi);
        return map;
    } else {
        return kernel_get_module_map(target);
    }
}

static int convert_exec_to_group(const char *exec, char **result)
{
    char *ptr1, *ptr2, *exec_copy;
    char buf[64];
    int ret;

    exec_copy = strdup(exec);
    if (!exec_copy)
        return -ENOMEM;

    ptr1 = basename(exec_copy);
    if (!ptr1) {
        ret = -EINVAL;
        goto out;
    }

    for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) {
        if (!isalnum(*ptr2) && *ptr2 != '_') {
            *ptr2 = '\0';
            break;
        }
    }

    ret = e_snprintf(buf, 64, "%s_%s", PERFPROBE_GROUP, ptr1);
    if (ret < 0)
        goto out;

    *result = strdup(buf);
    ret = *result ? 0 : -ENOMEM;

out:
    free(exec_copy);
    return ret;
}

static void clear_perf_probe_point(struct perf_probe_point *pp)
{
    free(pp->file);
    free(pp->function);
    free(pp->lazy_line);
}

static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
{
    int i;

    for (i = 0; i < ntevs; i++)
        clear_probe_trace_event(tevs + i);
}

static bool kprobe_blacklist__listed(unsigned long address);
static bool kprobe_warn_out_range(const char *symbol, unsigned long address)
{
    u64 etext_addr = 0;
    int ret;

    /* Get the address of _etext for checking non-probable text symbol */
    ret = kernel_get_symbol_address_by_name("_etext", &etext_addr,
                        false, false);

    if (ret == 0 && etext_addr < address)
        pr_warning("%s is out of .text, skip it.\n", symbol);
    else if (kprobe_blacklist__listed(address))
        pr_warning("%s is blacklisted function, skip it.\n", symbol);
    else
        return false;

    return true;
}

/*
 * @module can be module name of module file path. In case of path,
 * inspect elf and find out what is actual module name.
 * Caller has to free mod_name after using it.
 */
static char *find_module_name(const char *module)
{
    int fd;
    Elf *elf;
    GElf_Ehdr ehdr;
    GElf_Shdr shdr;
    Elf_Data *data;
    Elf_Scn *sec;
    char *mod_name = NULL;
    int name_offset;

    fd = open(module, O_RDONLY);
    if (fd < 0)
        return NULL;

    elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
    if (elf == NULL)
        goto elf_err;

    if (gelf_getehdr(elf, &ehdr) == NULL)
        goto ret_err;

    sec = elf_section_by_name(elf, &ehdr, &shdr,
            ".gnu.linkonce.this_module", NULL);
    if (!sec)
        goto ret_err;

    data = elf_getdata(sec, NULL);
    if (!data || !data->d_buf)
        goto ret_err;

    /*
     * NOTE:
     * '.gnu.linkonce.this_module' section of kernel module elf directly
     * maps to 'struct module' from linux/module.h. This section contains
     * actual module name which will be used by kernel after loading it.
     * But, we cannot use 'struct module' here since linux/module.h is not
     * exposed to user-space. Offset of 'name' has remained same from long
     * time, so hardcoding it here.
     */
    if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
        name_offset = 12;
    else    /* expect ELFCLASS64 by default */
        name_offset = 24;

    mod_name = strdup((char *)data->d_buf + name_offset);

ret_err:
    elf_end(elf);
elf_err:
    close(fd);
    return mod_name;
}

#ifdef HAVE_DWARF_SUPPORT

static int kernel_get_module_dso(const char *module, struct dso **pdso)
{
    struct dso *dso;
    struct map *map;
    const char *vmlinux_name;
    int ret = 0;

    if (module) {
        char module_name[128];

        snprintf(module_name, sizeof(module_name), "[%s]", module);
        map = map_groups__find_by_name(&host_machine->kmaps, module_name);
        if (map) {
            dso = map->dso;
            goto found;
        }
        pr_debug("Failed to find module %s.\n", module);
        return -ENOENT;
    }

    map = machine__kernel_map(host_machine);
    dso = map->dso;

    vmlinux_name = symbol_conf.vmlinux_name;
    dso->load_errno = 0;
    if (vmlinux_name)
        ret = dso__load_vmlinux(dso, map, vmlinux_name, false);
    else
        ret = dso__load_vmlinux_path(dso, map);
found:
    *pdso = dso;
    return ret;
}

/*
 * Some binaries like glibc have special symbols which are on the symbol
 * table, but not in the debuginfo. If we can find the address of the
 * symbol from map, we can translate the address back to the probe point.
 */
static int find_alternative_probe_point(struct debuginfo *dinfo,
                    struct perf_probe_point *pp,
                    struct perf_probe_point *result,
                    const char *target, struct nsinfo *nsi,
                    bool uprobes)
{
    struct map *map = NULL;
    struct symbol *sym;
    u64 address = 0;
    int ret = -ENOENT;

    /* This can work only for function-name based one */
    if (!pp->function || pp->file)
        return -ENOTSUP;

    map = get_target_map(target, nsi, uprobes);
    if (!map)
        return -EINVAL;

    /* Find the address of given function */
    map__for_each_symbol_by_name(map, pp->function, sym) {
        if (uprobes)
            address = sym->start;
        else
            address = map->unmap_ip(map, sym->start) - map->reloc;
        break;
    }
    if (!address) {
        ret = -ENOENT;
        goto out;
    }
    pr_debug("Symbol %s address found : %" PRIx64 "\n",
            pp->function, address);

    ret = debuginfo__find_probe_point(dinfo, (unsigned long)address,
                      result);
    if (ret <= 0)
        ret = (!ret) ? -ENOENT : ret;
    else {
        result->offset += pp->offset;
        result->line += pp->line;
        result->retprobe = pp->retprobe;
        ret = 0;
    }

out:
    map__put(map);
    return ret;

}

static int get_alternative_probe_event(struct debuginfo *dinfo,
                       struct perf_probe_event *pev,
                       struct perf_probe_point *tmp)
{
    int ret;

    memcpy(tmp, &pev->point, sizeof(*tmp));
    memset(&pev->point, 0, sizeof(pev->point));
    ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target,
                       pev->nsi, pev->uprobes);
    if (ret < 0)
        memcpy(&pev->point, tmp, sizeof(*tmp));

    return ret;
}

static int get_alternative_line_range(struct debuginfo *dinfo,
                      struct line_range *lr,
                      const char *target, bool user)
{
    struct perf_probe_point pp = { .function = lr->function,
                       .file = lr->file,
                       .line = lr->start };
    struct perf_probe_point result;
    int ret, len = 0;

    memset(&result, 0, sizeof(result));

    if (lr->end != INT_MAX)
        len = lr->end - lr->start;
    ret = find_alternative_probe_point(dinfo, &pp, &result,
                       target, NULL, user);
    if (!ret) {
        lr->function = result.function;
        lr->file = result.file;
        lr->start = result.line;
        if (lr->end != INT_MAX)
            lr->end = lr->start + len;
        clear_perf_probe_point(&pp);
    }
    return ret;
}

/* Open new debuginfo of given module */
static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi,
                    bool silent)
{
    const char *path = module;
    char reason[STRERR_BUFSIZE];
    struct debuginfo *ret = NULL;
    struct dso *dso = NULL;
    struct nscookie nsc;
    int err;

    if (!module || !strchr(module, '/')) {
        err = kernel_get_module_dso(module, &dso);
        if (err < 0) {
            if (!dso || dso->load_errno == 0) {
                if (!str_error_r(-err, reason, STRERR_BUFSIZE))
                    strcpy(reason, "(unknown)");
            } else
                dso__strerror_load(dso, reason, STRERR_BUFSIZE);
            if (!silent)
                pr_err("Failed to find the path for %s: %s\n",
                    module ?: "kernel", reason);
            return NULL;
        }
        path = dso->long_name;
    }
    nsinfo__mountns_enter(nsi, &nsc);
    ret = debuginfo__new(path);
    if (!ret && !silent) {
        pr_warning("The %s file has no debug information.\n", path);
        if (!module || !strtailcmp(path, ".ko"))
            pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, ");
        else
            pr_warning("Rebuild with -g, ");
        pr_warning("or install an appropriate debuginfo package.\n");
    }
    nsinfo__mountns_exit(&nsc);
    return ret;
}

/* For caching the last debuginfo */
static struct debuginfo *debuginfo_cache;
static char *debuginfo_cache_path;

static struct debuginfo *debuginfo_cache__open(const char *module, bool silent)
{
    const char *path = module;

    /* If the module is NULL, it should be the kernel. */
    if (!module)
        path = "kernel";

    if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path))
        goto out;

    /* Copy module path */
    free(debuginfo_cache_path);
    debuginfo_cache_path = strdup(path);
    if (!debuginfo_cache_path) {
        debuginfo__delete(debuginfo_cache);
        debuginfo_cache = NULL;
        goto out;
    }

    debuginfo_cache = open_debuginfo(module, NULL, silent);
    if (!debuginfo_cache)
        zfree(&debuginfo_cache_path);
out:
    return debuginfo_cache;
}

static void debuginfo_cache__exit(void)
{
    debuginfo__delete(debuginfo_cache);
    debuginfo_cache = NULL;
    zfree(&debuginfo_cache_path);
}


static int get_text_start_address(const char *exec, unsigned long *address,
                  struct nsinfo *nsi)
{
    Elf *elf;
    GElf_Ehdr ehdr;
    GElf_Shdr shdr;
    int fd, ret = -ENOENT;
    struct nscookie nsc;

    nsinfo__mountns_enter(nsi, &nsc);
    fd = open(exec, O_RDONLY);
    nsinfo__mountns_exit(&nsc);
    if (fd < 0)
        return -errno;

    elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
    if (elf == NULL) {
        ret = -EINVAL;
        goto out_close;
    }

    if (gelf_getehdr(elf, &ehdr) == NULL)
        goto out;

    if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL))
        goto out;

    *address = shdr.sh_addr - shdr.sh_offset;
    ret = 0;
out:
    elf_end(elf);
out_close:
    close(fd);

    return ret;
}

/*
 * Convert trace point to probe point with debuginfo
 */
static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
                        struct perf_probe_point *pp,
                        bool is_kprobe)
{
    struct debuginfo *dinfo = NULL;
    unsigned long stext = 0;
    u64 addr = tp->address;
    int ret = -ENOENT;

    /* convert the address to dwarf address */
    if (!is_kprobe) {
        if (!addr) {
            ret = -EINVAL;
            goto error;
        }
        ret = get_text_start_address(tp->module, &stext, NULL);
        if (ret < 0)
            goto error;
        addr += stext;
    } else if (tp->symbol) {
        /* If the module is given, this returns relative address */
        ret = kernel_get_symbol_address_by_name(tp->symbol, &addr,
                            false, !!tp->module);
        if (ret != 0)
            goto error;
        addr += tp->offset;
    }

    pr_debug("try to find information at %" PRIx64 " in %s\n", addr,
         tp->module ? : "kernel");

    dinfo = debuginfo_cache__open(tp->module, verbose <= 0);
    if (dinfo)
        ret = debuginfo__find_probe_point(dinfo,
                         (unsigned long)addr, pp);
    else
        ret = -ENOENT;

    if (ret > 0) {
        pp->retprobe = tp->retprobe;
        return 0;
    }
error:
    pr_debug("Failed to find corresponding probes from debuginfo.\n");
    return ret ? : -ENOENT;
}

/* Adjust symbol name and address */
static int post_process_probe_trace_point(struct probe_trace_point *tp,
                       struct map *map, unsigned long offs)
{
    struct symbol *sym;
    u64 addr = tp->address - offs;

    sym = map__find_symbol(map, addr);
    if (!sym)
        return -ENOENT;

    if (strcmp(sym->name, tp->symbol)) {
        /* If we have no realname, use symbol for it */
        if (!tp->realname)
            tp->realname = tp->symbol;
        else
            free(tp->symbol);
        tp->symbol = strdup(sym->name);
        if (!tp->symbol)
            return -ENOMEM;
    }
    tp->offset = addr - sym->start;
    tp->address -= offs;

    return 0;
}

/*
 * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions
 * and generate new symbols with suffixes such as .constprop.N or .isra.N
 * etc. Since those symbols are not recorded in DWARF, we have to find
 * correct generated symbols from offline ELF binary.
 * For online kernel or uprobes we don't need this because those are
 * rebased on _text, or already a section relative address.
 */
static int
post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
                    int ntevs, const char *pathname)
{
    struct map *map;
    unsigned long stext = 0;
    int i, ret = 0;

    /* Prepare a map for offline binary */
    map = dso__new_map(pathname);
    if (!map || get_text_start_address(pathname, &stext, NULL) < 0) {
        pr_warning("Failed to get ELF symbols for %s\n", pathname);
        return -EINVAL;
    }

    for (i = 0; i < ntevs; i++) {
        ret = post_process_probe_trace_point(&tevs[i].point,
                             map, stext);
        if (ret < 0)
            break;
    }
    map__put(map);

    return ret;
}

static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
                      int ntevs, const char *exec,
                      struct nsinfo *nsi)
{
    int i, ret = 0;
    unsigned long stext = 0;

    if (!exec)
        return 0;

    ret = get_text_start_address(exec, &stext, nsi);
    if (ret < 0)
        return ret;

    for (i = 0; i < ntevs && ret >= 0; i++) {
        /* point.address is the addres of point.symbol + point.offset */
        tevs[i].point.address -= stext;
        tevs[i].point.module = strdup(exec);
        if (!tevs[i].point.module) {
            ret = -ENOMEM;
            break;
        }
        tevs[i].uprobes = true;
    }

    return ret;
}

static int
post_process_module_probe_trace_events(struct probe_trace_event *tevs,
                       int ntevs, const char *module,
                       struct debuginfo *dinfo)
{
    Dwarf_Addr text_offs = 0;
    int i, ret = 0;
    char *mod_name = NULL;
    struct map *map;

    if (!module)
        return 0;

    map = get_target_map(module, NULL, false);
    if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) {
        pr_warning("Failed to get ELF symbols for %s\n", module);
        return -EINVAL;
    }

    mod_name = find_module_name(module);
    for (i = 0; i < ntevs; i++) {
        ret = post_process_probe_trace_point(&tevs[i].point,
                        map, (unsigned long)text_offs);
        if (ret < 0)
            break;
        tevs[i].point.module =
            strdup(mod_name ? mod_name : module);
        if (!tevs[i].point.module) {
            ret = -ENOMEM;
            break;
        }
    }

    free(mod_name);
    map__put(map);

    return ret;
}

static int
post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
                       int ntevs)
{
    struct ref_reloc_sym *reloc_sym;
    char *tmp;
    int i, skipped = 0;

    /* Skip post process if the target is an offline kernel */
    if (symbol_conf.ignore_vmlinux_buildid)
        return post_process_offline_probe_trace_events(tevs, ntevs,
                        symbol_conf.vmlinux_name);

    reloc_sym = kernel_get_ref_reloc_sym();
    if (!reloc_sym) {
        pr_warning("Relocated base symbol is not found!\n");
        return -EINVAL;
    }

    for (i = 0; i < ntevs; i++) {
        if (!tevs[i].point.address)
            continue;
        if (tevs[i].point.retprobe && !kretprobe_offset_is_supported())
            continue;
        /* If we found a wrong one, mark it by NULL symbol */
        if (kprobe_warn_out_range(tevs[i].point.symbol,
                      tevs[i].point.address)) {
            tmp = NULL;
            skipped++;
        } else {
            tmp = strdup(reloc_sym->name);
            if (!tmp)
                return -ENOMEM;
        }
        /* If we have no realname, use symbol for it */
        if (!tevs[i].point.realname)
            tevs[i].point.realname = tevs[i].point.symbol;
        else
            free(tevs[i].point.symbol);
        tevs[i].point.symbol = tmp;
        tevs[i].point.offset = tevs[i].point.address -
                       reloc_sym->unrelocated_addr;
    }
    return skipped;
}

void __weak
arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused,
                      int ntevs __maybe_unused)
{
}

/* Post processing the probe events */
static int post_process_probe_trace_events(struct perf_probe_event *pev,
                       struct probe_trace_event *tevs,
                       int ntevs, const char *module,
                       bool uprobe, struct debuginfo *dinfo)
{
    int ret;

    if (uprobe)
        ret = add_exec_to_probe_trace_events(tevs, ntevs, module,
                             pev->nsi);
    else if (module)
        /* Currently ref_reloc_sym based probe is not for drivers */
        ret = post_process_module_probe_trace_events(tevs, ntevs,
                                 module, dinfo);
    else
        ret = post_process_kernel_probe_trace_events(tevs, ntevs);

    if (ret >= 0)
        arch__post_process_probe_trace_events(pev, ntevs);

    return ret;
}

/* Try to find perf_probe_event with debuginfo */
static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                      struct probe_trace_event **tevs)
{
    bool need_dwarf = perf_probe_event_need_dwarf(pev);
    struct perf_probe_point tmp;
    struct debuginfo *dinfo;
    int ntevs, ret = 0;

    dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf);
    if (!dinfo) {
        if (need_dwarf)
            return -ENOENT;
        pr_debug("Could not open debuginfo. Try to use symbols.\n");
        return 0;
    }

    pr_debug("Try to find probe point from debuginfo.\n");
    /* Searching trace events corresponding to a probe event */
    ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);

    if (ntevs == 0) {  /* Not found, retry with an alternative */
        ret = get_alternative_probe_event(dinfo, pev, &tmp);
        if (!ret) {
            ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
            /*
             * Write back to the original probe_event for
             * setting appropriate (user given) event name
             */
            clear_perf_probe_point(&pev->point);
            memcpy(&pev->point, &tmp, sizeof(tmp));
        }
    }

    if (ntevs > 0) {    /* Succeeded to find trace events */
        pr_debug("Found %d probe_trace_events.\n", ntevs);
        ret = post_process_probe_trace_events(pev, *tevs, ntevs,
                    pev->target, pev->uprobes, dinfo);
        if (ret < 0 || ret == ntevs) {
            pr_debug("Post processing failed or all events are skipped. (%d)\n", ret);
            clear_probe_trace_events(*tevs, ntevs);
            zfree(tevs);
            ntevs = 0;
        }
    }

    debuginfo__delete(dinfo);

    if (ntevs == 0) {   /* No error but failed to find probe point. */
        pr_warning("Probe point '%s' not found.\n",
               synthesize_perf_probe_point(&pev->point));
        return -ENOENT;
    } else if (ntevs < 0) {
        /* Error path : ntevs < 0 */
        pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
        if (ntevs == -EBADF)
            pr_warning("Warning: No dwarf info found in the vmlinux - "
                "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
        if (!need_dwarf) {
            pr_debug("Trying to use symbols.\n");
            return 0;
        }
    }
    return ntevs;
}

#define LINEBUF_SIZE 256
#define NR_ADDITIONAL_LINES 2

static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
{
    char buf[LINEBUF_SIZE], sbuf[STRERR_BUFSIZE];
    const char *color = show_num ? "" : PERF_COLOR_BLUE;
    const char *prefix = NULL;

    do {
        if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
            goto error;
        if (skip)
            continue;
        if (!prefix) {
            prefix = show_num ? "%7d  " : "         ";
            color_fprintf(stdout, color, prefix, l);
        }
        color_fprintf(stdout, color, "%s", buf);

    } while (strchr(buf, '\n') == NULL);

    return 1;
error:
    if (ferror(fp)) {
        pr_warning("File read error: %s\n",
               str_error_r(errno, sbuf, sizeof(sbuf)));
        return -1;
    }
    return 0;
}

static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
{
    int rv = __show_one_line(fp, l, skip, show_num);
    if (rv == 0) {
        pr_warning("Source file is shorter than expected.\n");
        rv = -1;
    }
    return rv;
}

#define show_one_line_with_num(f,l) _show_one_line(f,l,false,true)
#define show_one_line(f,l)      _show_one_line(f,l,false,false)
#define skip_one_line(f,l)      _show_one_line(f,l,true,false)
#define show_one_line_or_eof(f,l)   __show_one_line(f,l,false,false)

/*
 * Show line-range always requires debuginfo to find source file and
 * line number.
 */
static int __show_line_range(struct line_range *lr, const char *module,
                 bool user)
{
    int l = 1;
    struct int_node *ln;
    struct debuginfo *dinfo;
    FILE *fp;
    int ret;
    char *tmp;
    char sbuf[STRERR_BUFSIZE];

    /* Search a line range */
    dinfo = open_debuginfo(module, NULL, false);
    if (!dinfo)
        return -ENOENT;

    ret = debuginfo__find_line_range(dinfo, lr);
    if (!ret) { /* Not found, retry with an alternative */
        ret = get_alternative_line_range(dinfo, lr, module, user);
        if (!ret)
            ret = debuginfo__find_line_range(dinfo, lr);
    }
    debuginfo__delete(dinfo);
    if (ret == 0 || ret == -ENOENT) {
        pr_warning("Specified source line is not found.\n");
        return -ENOENT;
    } else if (ret < 0) {
        pr_warning("Debuginfo analysis failed.\n");
        return ret;
    }

    /* Convert source file path */
    tmp = lr->path;
    ret = get_real_path(tmp, lr->comp_dir, &lr->path);

    /* Free old path when new path is assigned */
    if (tmp != lr->path)
        free(tmp);

    if (ret < 0) {
        pr_warning("Failed to find source file path.\n");
        return ret;
    }

    setup_pager();

    if (lr->function)
        fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
            lr->start - lr->offset);
    else
        fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);

    fp = fopen(lr->path, "r");
    if (fp == NULL) {
        pr_warning("Failed to open %s: %s\n", lr->path,
               str_error_r(errno, sbuf, sizeof(sbuf)));
        return -errno;
    }
    /* Skip to starting line number */
    while (l < lr->start) {
        ret = skip_one_line(fp, l++);
        if (ret < 0)
            goto end;
    }

    intlist__for_each_entry(ln, lr->line_list) {
        for (; ln->i > l; l++) {
            ret = show_one_line(fp, l - lr->offset);
            if (ret < 0)
                goto end;
        }
        ret = show_one_line_with_num(fp, l++ - lr->offset);
        if (ret < 0)
            goto end;
    }

    if (lr->end == INT_MAX)
        lr->end = l + NR_ADDITIONAL_LINES;
    while (l <= lr->end) {
        ret = show_one_line_or_eof(fp, l++ - lr->offset);
        if (ret <= 0)
            break;
    }
end:
    fclose(fp);
    return ret;
}

int show_line_range(struct line_range *lr, const char *module,
            struct nsinfo *nsi, bool user)
{
    int ret;
    struct nscookie nsc;

    ret = init_probe_symbol_maps(user);
    if (ret < 0)
        return ret;
    nsinfo__mountns_enter(nsi, &nsc);
    ret = __show_line_range(lr, module, user);
    nsinfo__mountns_exit(&nsc);
    exit_probe_symbol_maps();

    return ret;
}

static int show_available_vars_at(struct debuginfo *dinfo,
                  struct perf_probe_event *pev,
                  struct strfilter *_filter)
{
    char *buf;
    int ret, i, nvars;
    struct str_node *node;
    struct variable_list *vls = NULL, *vl;
    struct perf_probe_point tmp;
    const char *var;

    buf = synthesize_perf_probe_point(&pev->point);
    if (!buf)
        return -EINVAL;
    pr_debug("Searching variables at %s\n", buf);

    ret = debuginfo__find_available_vars_at(dinfo, pev, &vls);
    if (!ret) {  /* Not found, retry with an alternative */
        ret = get_alternative_probe_event(dinfo, pev, &tmp);
        if (!ret) {
            ret = debuginfo__find_available_vars_at(dinfo, pev,
                                &vls);
            /* Release the old probe_point */
            clear_perf_probe_point(&tmp);
        }
    }
    if (ret <= 0) {
        if (ret == 0 || ret == -ENOENT) {
            pr_err("Failed to find the address of %s\n", buf);
            ret = -ENOENT;
        } else
            pr_warning("Debuginfo analysis failed.\n");
        goto end;
    }

    /* Some variables are found */
    fprintf(stdout, "Available variables at %s\n", buf);
    for (i = 0; i < ret; i++) {
        vl = &vls[i];
        /*
         * A probe point might be converted to
         * several trace points.
         */
        fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
            vl->point.offset);
        zfree(&vl->point.symbol);
        nvars = 0;
        if (vl->vars) {
            strlist__for_each_entry(node, vl->vars) {
                var = strchr(node->s, '\t') + 1;
                if (strfilter__compare(_filter, var)) {
                    fprintf(stdout, "\t\t%s\n", node->s);
                    nvars++;
                }
            }
            strlist__delete(vl->vars);
        }
        if (nvars == 0)
            fprintf(stdout, "\t\t(No matched variables)\n");
    }
    free(vls);
end:
    free(buf);
    return ret;
}

/* Show available variables on given probe point */
int show_available_vars(struct perf_probe_event *pevs, int npevs,
            struct strfilter *_filter)
{
    int i, ret = 0;
    struct debuginfo *dinfo;

    ret = init_probe_symbol_maps(pevs->uprobes);
    if (ret < 0)
        return ret;

    dinfo = open_debuginfo(pevs->target, pevs->nsi, false);
    if (!dinfo) {
        ret = -ENOENT;
        goto out;
    }

    setup_pager();

    for (i = 0; i < npevs && ret >= 0; i++)
        ret = show_available_vars_at(dinfo, &pevs[i], _filter);

    debuginfo__delete(dinfo);
out:
    exit_probe_symbol_maps();
    return ret;
}

#else   /* !HAVE_DWARF_SUPPORT */

static void debuginfo_cache__exit(void)
{
}

static int
find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused,
                 struct perf_probe_point *pp __maybe_unused,
                 bool is_kprobe __maybe_unused)
{
    return -ENOSYS;
}

static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                struct probe_trace_event **tevs __maybe_unused)
{
    if (perf_probe_event_need_dwarf(pev)) {
        pr_warning("Debuginfo-analysis is not supported.\n");
        return -ENOSYS;
    }

    return 0;
}

int show_line_range(struct line_range *lr __maybe_unused,
            const char *module __maybe_unused,
            struct nsinfo *nsi __maybe_unused,
            bool user __maybe_unused)
{
    pr_warning("Debuginfo-analysis is not supported.\n");
    return -ENOSYS;
}

int show_available_vars(struct perf_probe_event *pevs __maybe_unused,
            int npevs __maybe_unused,
            struct strfilter *filter __maybe_unused)
{
    pr_warning("Debuginfo-analysis is not supported.\n");
    return -ENOSYS;
}
#endif

void line_range__clear(struct line_range *lr)
{
    free(lr->function);
    free(lr->file);
    free(lr->path);
    free(lr->comp_dir);
    intlist__delete(lr->line_list);
    memset(lr, 0, sizeof(*lr));
}

int line_range__init(struct line_range *lr)
{
    memset(lr, 0, sizeof(*lr));
    lr->line_list = intlist__new(NULL);
    if (!lr->line_list)
        return -ENOMEM;
    else
        return 0;
}

static int parse_line_num(char **ptr, int *val, const char *what)
{
    const char *start = *ptr;

    errno = 0;
    *val = strtol(*ptr, ptr, 0);
    if (errno || *ptr == start) {
        semantic_error("'%s' is not a valid number.\n", what);
        return -EINVAL;
    }
    return 0;
}

/* Check the name is good for event, group or function */
static bool is_c_func_name(const char *name)
{
    if (!isalpha(*name) && *name != '_')
        return false;
    while (*++name != '\0') {
        if (!isalpha(*name) && !isdigit(*name) && *name != '_')
            return false;
    }
    return true;
}

/*
 * Stuff 'lr' according to the line range described by 'arg'.
 * The line range syntax is described by:
 *
 *         SRC[:SLN[+NUM|-ELN]]
 *         FNC[@SRC][:SLN[+NUM|-ELN]]
 */
int parse_line_range_desc(const char *arg, struct line_range *lr)
{
    char *range, *file, *name = strdup(arg);
    int err;

    if (!name)
        return -ENOMEM;

    lr->start = 0;
    lr->end = INT_MAX;

    range = strchr(name, ':');
    if (range) {
        *range++ = '\0';

        err = parse_line_num(&range, &lr->start, "start line");
        if (err)
            goto err;

        if (*range == '+' || *range == '-') {
            const char c = *range++;

            err = parse_line_num(&range, &lr->end, "end line");
            if (err)
                goto err;

            if (c == '+') {
                lr->end += lr->start;
                /*
                 * Adjust the number of lines here.
                 * If the number of lines == 1, the
                 * the end of line should be equal to
                 * the start of line.
                 */
                lr->end--;
            }
        }

        pr_debug("Line range is %d to %d\n", lr->start, lr->end);

        err = -EINVAL;
        if (lr->start > lr->end) {
            semantic_error("Start line must be smaller"
                       " than end line.\n");
            goto err;
        }
        if (*range != '\0') {
            semantic_error("Tailing with invalid str '%s'.\n", range);
            goto err;
        }
    }

    file = strchr(name, '@');
    if (file) {
        *file = '\0';
        lr->file = strdup(++file);
        if (lr->file == NULL) {
            err = -ENOMEM;
            goto err;
        }
        lr->function = name;
    } else if (strchr(name, '/') || strchr(name, '.'))
        lr->file = name;
    else if (is_c_func_name(name))/* We reuse it for checking funcname */
        lr->function = name;
    else {  /* Invalid name */
        semantic_error("'%s' is not a valid function name.\n", name);
        err = -EINVAL;
        goto err;
    }

    return 0;
err:
    free(name);
    return err;
}

static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev)
{
    char *ptr;

    ptr = strpbrk_esc(*arg, ":");
    if (ptr) {
        *ptr = '\0';
        if (!pev->sdt && !is_c_func_name(*arg))
            goto ng_name;
        pev->group = strdup_esc(*arg);
        if (!pev->group)
            return -ENOMEM;
        *arg = ptr + 1;
    } else
        pev->group = NULL;

    pev->event = strdup_esc(*arg);
    if (pev->event == NULL)
        return -ENOMEM;

    if (!pev->sdt && !is_c_func_name(pev->event)) {
        zfree(&pev->event);
ng_name:
        zfree(&pev->group);
        semantic_error("%s is bad for event name -it must "
                   "follow C symbol-naming rule.\n", *arg);
        return -EINVAL;
    }
    return 0;
}

/* Parse probepoint definition. */
static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
{
    struct perf_probe_point *pp = &pev->point;
    char *ptr, *tmp;
    char c, nc = 0;
    bool file_spec = false;
    int ret;

    /*
     * <Syntax>
     * perf probe [GRP:][EVENT=]SRC[:LN|;PTN]
     * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
     * perf probe %[GRP:]SDT_EVENT
     */
    if (!arg)
        return -EINVAL;

    if (is_sdt_event(arg)) {
        pev->sdt = true;
        if (arg[0] == '%')
            arg++;
    }

    ptr = strpbrk_esc(arg, ";=@+%");
    if (pev->sdt) {
        if (ptr) {
            if (*ptr != '@') {
                semantic_error("%s must be an SDT name.\n",
                           arg);
                return -EINVAL;
            }
            /* This must be a target file name or build id */
            tmp = build_id_cache__complement(ptr + 1);
            if (tmp) {
                pev->target = build_id_cache__origname(tmp);
                free(tmp);
            } else
                pev->target = strdup_esc(ptr + 1);
            if (!pev->target)
                return -ENOMEM;
            *ptr = '\0';
        }
        ret = parse_perf_probe_event_name(&arg, pev);
        if (ret == 0) {
            if (asprintf(&pev->point.function, "%%%s", pev->event) < 0)
                ret = -errno;
        }
        return ret;
    }

    if (ptr && *ptr == '=') {   /* Event name */
        *ptr = '\0';
        tmp = ptr + 1;
        ret = parse_perf_probe_event_name(&arg, pev);
        if (ret < 0)
            return ret;

        arg = tmp;
    }

    /*
     * Check arg is function or file name and copy it.
     *
     * We consider arg to be a file spec if and only if it satisfies
     * all of the below criteria::
     * - it does not include any of "+@%",
     * - it includes one of ":;", and
     * - it has a period '.' in the name.
     *
     * Otherwise, we consider arg to be a function specification.
     */
    if (!strpbrk_esc(arg, "+@%")) {
        ptr = strpbrk_esc(arg, ";:");
        /* This is a file spec if it includes a '.' before ; or : */
        if (ptr && memchr(arg, '.', ptr - arg))
            file_spec = true;
    }

    ptr = strpbrk_esc(arg, ";:+@%");
    if (ptr) {
        nc = *ptr;
        *ptr++ = '\0';
    }

    if (arg[0] == '\0')
        tmp = NULL;
    else {
        tmp = strdup_esc(arg);
        if (tmp == NULL)
            return -ENOMEM;
    }

    if (file_spec)
        pp->file = tmp;
    else {
        pp->function = tmp;

        /*
         * Keep pp->function even if this is absolute address,
         * so it can mark whether abs_address is valid.
         * Which make 'perf probe lib.bin 0x0' possible.
         *
         * Note that checking length of tmp is not needed
         * because when we access tmp[1] we know tmp[0] is '0',
         * so tmp[1] should always valid (but could be '\0').
         */
        if (tmp && !strncmp(tmp, "0x", 2)) {
            pp->abs_address = strtoul(pp->function, &tmp, 0);
            if (*tmp != '\0') {
                semantic_error("Invalid absolute address.\n");
                return -EINVAL;
            }
        }
    }

    /* Parse other options */
    while (ptr) {
        arg = ptr;
        c = nc;
        if (c == ';') { /* Lazy pattern must be the last part */
            pp->lazy_line = strdup(arg); /* let leave escapes */
            if (pp->lazy_line == NULL)
                return -ENOMEM;
            break;
        }
        ptr = strpbrk_esc(arg, ";:+@%");
        if (ptr) {
            nc = *ptr;
            *ptr++ = '\0';
        }
        switch (c) {
        case ':':   /* Line number */
            pp->line = strtoul(arg, &tmp, 0);
            if (*tmp != '\0') {
                semantic_error("There is non-digit char"
                           " in line number.\n");
                return -EINVAL;
            }
            break;
        case '+':   /* Byte offset from a symbol */
            pp->offset = strtoul(arg, &tmp, 0);
            if (*tmp != '\0') {
                semantic_error("There is non-digit character"
                        " in offset.\n");
                return -EINVAL;
            }
            break;
        case '@':   /* File name */
            if (pp->file) {
                semantic_error("SRC@SRC is not allowed.\n");
                return -EINVAL;
            }
            pp->file = strdup_esc(arg);
            if (pp->file == NULL)
                return -ENOMEM;
            break;
        case '%':   /* Probe places */
            if (strcmp(arg, "return") == 0) {
                pp->retprobe = 1;
            } else {    /* Others not supported yet */
                semantic_error("%%%s is not supported.\n", arg);
                return -ENOTSUP;
            }
            break;
        default:    /* Buggy case */
            pr_err("This program has a bug at %s:%d.\n",
                __FILE__, __LINE__);
            return -ENOTSUP;
            break;
        }
    }

    /* Exclusion check */
    if (pp->lazy_line && pp->line) {
        semantic_error("Lazy pattern can't be used with"
                   " line number.\n");
        return -EINVAL;
    }

    if (pp->lazy_line && pp->offset) {
        semantic_error("Lazy pattern can't be used with offset.\n");
        return -EINVAL;
    }

    if (pp->line && pp->offset) {
        semantic_error("Offset can't be used with line number.\n");
        return -EINVAL;
    }

    if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
        semantic_error("File always requires line number or "
                   "lazy pattern.\n");
        return -EINVAL;
    }

    if (pp->offset && !pp->function) {
        semantic_error("Offset requires an entry function.\n");
        return -EINVAL;
    }

    if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
        semantic_error("Offset/Line/Lazy pattern can't be used with "
                   "return probe.\n");
        return -EINVAL;
    }

    pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
         pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
         pp->lazy_line);
    return 0;
}

/* Parse perf-probe event argument */
static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
{
    char *tmp, *goodname;
    struct perf_probe_arg_field **fieldp;

    pr_debug("parsing arg: %s into ", str);

    tmp = strchr(str, '=');
    if (tmp) {
        arg->name = strndup(str, tmp - str);
        if (arg->name == NULL)
            return -ENOMEM;
        pr_debug("name:%s ", arg->name);
        str = tmp + 1;
    }

    tmp = strchr(str, ':');
    if (tmp) {  /* Type setting */
        *tmp = '\0';
        arg->type = strdup(tmp + 1);
        if (arg->type == NULL)
            return -ENOMEM;
        pr_debug("type:%s ", arg->type);
    }

    tmp = strpbrk(str, "-.[");
    if (!is_c_varname(str) || !tmp) {
        /* A variable, register, symbol or special value */
        arg->var = strdup(str);
        if (arg->var == NULL)
            return -ENOMEM;
        pr_debug("%s\n", arg->var);
        return 0;
    }

    /* Structure fields or array element */
    arg->var = strndup(str, tmp - str);
    if (arg->var == NULL)
        return -ENOMEM;
    goodname = arg->var;
    pr_debug("%s, ", arg->var);
    fieldp = &arg->field;

    do {
        *fieldp = zalloc(sizeof(struct perf_probe_arg_field));
        if (*fieldp == NULL)
            return -ENOMEM;
        if (*tmp == '[') {  /* Array */
            str = tmp;
            (*fieldp)->index = strtol(str + 1, &tmp, 0);
            (*fieldp)->ref = true;
            if (*tmp != ']' || tmp == str + 1) {
                semantic_error("Array index must be a"
                        " number.\n");
                return -EINVAL;
            }
            tmp++;
            if (*tmp == '\0')
                tmp = NULL;
        } else {        /* Structure */
            if (*tmp == '.') {
                str = tmp + 1;
                (*fieldp)->ref = false;
            } else if (tmp[1] == '>') {
                str = tmp + 2;
                (*fieldp)->ref = true;
            } else {
                semantic_error("Argument parse error: %s\n",
                           str);
                return -EINVAL;
            }
            tmp = strpbrk(str, "-.[");
        }
        if (tmp) {
            (*fieldp)->name = strndup(str, tmp - str);
            if ((*fieldp)->name == NULL)
                return -ENOMEM;
            if (*str != '[')
                goodname = (*fieldp)->name;
            pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
            fieldp = &(*fieldp)->next;
        }
    } while (tmp);
    (*fieldp)->name = strdup(str);
    if ((*fieldp)->name == NULL)
        return -ENOMEM;
    if (*str != '[')
        goodname = (*fieldp)->name;
    pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);

    /* If no name is specified, set the last field name (not array index)*/
    if (!arg->name) {
        arg->name = strdup(goodname);
        if (arg->name == NULL)
            return -ENOMEM;
    }
    return 0;
}

/* Parse perf-probe event command */
int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
{
    char **argv;
    int argc, i, ret = 0;

    argv = argv_split(cmd, &argc);
    if (!argv) {
        pr_debug("Failed to split arguments.\n");
        return -ENOMEM;
    }
    if (argc - 1 > MAX_PROBE_ARGS) {
        semantic_error("Too many probe arguments (%d).\n", argc - 1);
        ret = -ERANGE;
        goto out;
    }
    /* Parse probe point */
    ret = parse_perf_probe_point(argv[0], pev);
    if (ret < 0)
        goto out;

    /* Copy arguments and ensure return probe has no C argument */
    pev->nargs = argc - 1;
    pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
    if (pev->args == NULL) {
        ret = -ENOMEM;
        goto out;
    }
    for (i = 0; i < pev->nargs && ret >= 0; i++) {
        ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
        if (ret >= 0 &&
            is_c_varname(pev->args[i].var) && pev->point.retprobe) {
            semantic_error("You can't specify local variable for"
                       " kretprobe.\n");
            ret = -EINVAL;
        }
    }
out:
    argv_free(argv);

    return ret;
}

/* Returns true if *any* ARG is either C variable, $params or $vars. */
bool perf_probe_with_var(struct perf_probe_event *pev)
{
    int i = 0;

    for (i = 0; i < pev->nargs; i++)
        if (is_c_varname(pev->args[i].var)              ||
            !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) ||
            !strcmp(pev->args[i].var, PROBE_ARG_VARS))
            return true;
    return false;
}

/* Return true if this perf_probe_event requires debuginfo */
bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
{
    if (pev->point.file || pev->point.line || pev->point.lazy_line)
        return true;

    if (perf_probe_with_var(pev))
        return true;

    return false;
}

/* Parse probe_events event into struct probe_point */
int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
{
    struct probe_trace_point *tp = &tev->point;
    char pr;
    char *p;
    char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str;
    int ret, i, argc;
    char **argv;

    pr_debug("Parsing probe_events: %s\n", cmd);
    argv = argv_split(cmd, &argc);
    if (!argv) {
        pr_debug("Failed to split arguments.\n");
        return -ENOMEM;
    }
    if (argc < 2) {
        semantic_error("Too few probe arguments.\n");
        ret = -ERANGE;
        goto out;
    }

    /* Scan event and group name. */
    argv0_str = strdup(argv[0]);
    if (argv0_str == NULL) {
        ret = -ENOMEM;
        goto out;
    }
    fmt1_str = strtok_r(argv0_str, ":", &fmt);
    fmt2_str = strtok_r(NULL, "/", &fmt);
    fmt3_str = strtok_r(NULL, " \t", &fmt);
    if (fmt1_str == NULL || strlen(fmt1_str) != 1 || fmt2_str == NULL
        || fmt3_str == NULL) {
        semantic_error("Failed to parse event name: %s\n", argv[0]);
        ret = -EINVAL;
        goto out;
    }
    pr = fmt1_str[0];
    tev->group = strdup(fmt2_str);
    tev->event = strdup(fmt3_str);
    if (tev->group == NULL || tev->event == NULL) {
        ret = -ENOMEM;
        goto out;
    }
    pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);

    tp->retprobe = (pr == 'r');

    /* Scan module name(if there), function name and offset */
    p = strchr(argv[1], ':');
    if (p) {
        tp->module = strndup(argv[1], p - argv[1]);
        if (!tp->module) {
            ret = -ENOMEM;
            goto out;
        }
        tev->uprobes = (tp->module[0] == '/');
        p++;
    } else
        p = argv[1];
    fmt1_str = strtok_r(p, "+", &fmt);
    /* only the address started with 0x */
    if (fmt1_str[0] == '0') {
        /*
         * Fix a special case:
         * if address == 0, kernel reports something like:
         * p:probe_libc/abs_0 /lib/libc-2.18.so:0x          (null) arg1=%ax
         * Newer kernel may fix that, but we want to
         * support old kernel also.
         */
        if (strcmp(fmt1_str, "0x") == 0) {
            if (!argv[2] || strcmp(argv[2], "(null)")) {
                ret = -EINVAL;
                goto out;
            }
            tp->address = 0;

            free(argv[2]);
            for (i = 2; argv[i + 1] != NULL; i++)
                argv[i] = argv[i + 1];

            argv[i] = NULL;
            argc -= 1;
        } else
            tp->address = strtoul(fmt1_str, NULL, 0);
    } else {
        /* Only the symbol-based probe has offset */
        tp->symbol = strdup(fmt1_str);
        if (tp->symbol == NULL) {
            ret = -ENOMEM;
            goto out;
        }
        fmt2_str = strtok_r(NULL, "", &fmt);
        if (fmt2_str == NULL)
            tp->offset = 0;
        else
            tp->offset = strtoul(fmt2_str, NULL, 10);
    }

    tev->nargs = argc - 2;
    tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
    if (tev->args == NULL) {
        ret = -ENOMEM;
        goto out;
    }
    for (i = 0; i < tev->nargs; i++) {
        p = strchr(argv[i + 2], '=');
        if (p)  /* We don't need which register is assigned. */
            *p++ = '\0';
        else
            p = argv[i + 2];
        tev->args[i].name = strdup(argv[i + 2]);
        /* TODO: parse regs and offset */
        tev->args[i].value = strdup(p);
        if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
            ret = -ENOMEM;
            goto out;
        }
    }
    ret = 0;
out:
    free(argv0_str);
    argv_free(argv);
    return ret;
}

/* Compose only probe arg */
char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
{
    struct perf_probe_arg_field *field = pa->field;
    struct strbuf buf;
    char *ret = NULL;
    int err;

    if (strbuf_init(&buf, 64) < 0)
        return NULL;

    if (pa->name && pa->var)
        err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
    else
        err = strbuf_addstr(&buf, pa->name ?: pa->var);
    if (err)
        goto out;

    while (field) {
        if (field->name[0] == '[')
            err = strbuf_addstr(&buf, field->name);
        else
            err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
                      field->name);
        field = field->next;
        if (err)
            goto out;
    }

    if (pa->type)
        if (strbuf_addf(&buf, ":%s", pa->type) < 0)
            goto out;

    ret = strbuf_detach(&buf, NULL);
out:
    strbuf_release(&buf);
    return ret;
}

/* Compose only probe point (not argument) */
char *synthesize_perf_probe_point(struct perf_probe_point *pp)
{
    struct strbuf buf;
    char *tmp, *ret = NULL;
    int len, err = 0;

    if (strbuf_init(&buf, 64) < 0)
        return NULL;

    if (pp->function) {
        if (strbuf_addstr(&buf, pp->function) < 0)
            goto out;
        if (pp->offset)
            err = strbuf_addf(&buf, "+%lu", pp->offset);
        else if (pp->line)
            err = strbuf_addf(&buf, ":%d", pp->line);
        else if (pp->retprobe)
            err = strbuf_addstr(&buf, "%return");
        if (err)
            goto out;
    }
    if (pp->file) {
        tmp = pp->file;
        len = strlen(tmp);
        if (len > 30) {
            tmp = strchr(pp->file + len - 30, '/');
            tmp = tmp ? tmp + 1 : pp->file + len - 30;
        }
        err = strbuf_addf(&buf, "@%s", tmp);
        if (!err && !pp->function && pp->line)
            err = strbuf_addf(&buf, ":%d", pp->line);
    }
    if (!err)
        ret = strbuf_detach(&buf, NULL);
out:
    strbuf_release(&buf);
    return ret;
}

char *synthesize_perf_probe_command(struct perf_probe_event *pev)
{
    struct strbuf buf;
    char *tmp, *ret = NULL;
    int i;

    if (strbuf_init(&buf, 64))
        return NULL;
    if (pev->event)
        if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP,
                pev->event) < 0)
            goto out;

    tmp = synthesize_perf_probe_point(&pev->point);
    if (!tmp || strbuf_addstr(&buf, tmp) < 0)
        goto out;
    free(tmp);

    for (i = 0; i < pev->nargs; i++) {
        tmp = synthesize_perf_probe_arg(pev->args + i);
        if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0)
            goto out;
        free(tmp);
    }

    ret = strbuf_detach(&buf, NULL);
out:
    strbuf_release(&buf);
    return ret;
}

static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
                        struct strbuf *buf, int depth)
{
    int err;
    if (ref->next) {
        depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
                             depth + 1);
        if (depth < 0)
            return depth;
    }
    err = strbuf_addf(buf, "%+ld(", ref->offset);
    return (err < 0) ? err : depth;
}

static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
                      struct strbuf *buf)
{
    struct probe_trace_arg_ref *ref = arg->ref;
    int depth = 0, err;

    /* Argument name or separator */
    if (arg->name)
        err = strbuf_addf(buf, " %s=", arg->name);
    else
        err = strbuf_addch(buf, ' ');
    if (err)
        return err;

    /* Special case: @XXX */
    if (arg->value[0] == '@' && arg->ref)
            ref = ref->next;

    /* Dereferencing arguments */
    if (ref) {
        depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
        if (depth < 0)
            return depth;
    }

    /* Print argument value */
    if (arg->value[0] == '@' && arg->ref)
        err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
    else
        err = strbuf_addstr(buf, arg->value);

    /* Closing */
    while (!err && depth--)
        err = strbuf_addch(buf, ')');

    /* Print argument type */
    if (!err && arg->type)
        err = strbuf_addf(buf, ":%s", arg->type);

    return err;
}

char *synthesize_probe_trace_command(struct probe_trace_event *tev)
{
    struct probe_trace_point *tp = &tev->point;
    struct strbuf buf;
    char *ret = NULL;
    int i, err;

    /* Uprobes must have tp->module */
    if (tev->uprobes && !tp->module)
        return NULL;

    if (strbuf_init(&buf, 32) < 0)
        return NULL;

    if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
            tev->group, tev->event) < 0)
        goto error;
    /*
     * If tp->address == 0, then this point must be a
     * absolute address uprobe.
     * try_to_find_absolute_address() should have made
     * tp->symbol to "0x0".
     */
    if (tev->uprobes && !tp->address) {
        if (!tp->symbol || strcmp(tp->symbol, "0x0"))
            goto error;
    }

    /* Use the tp->address for uprobes */
    if (tev->uprobes)
        err = strbuf_addf(&buf, "%s:0x%lx", tp->module, tp->address);
    else if (!strncmp(tp->symbol, "0x", 2))
        /* Absolute address. See try_to_find_absolute_address() */
        err = strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "",
                  tp->module ? ":" : "", tp->address);
    else
        err = strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "",
                tp->module ? ":" : "", tp->symbol, tp->offset);
    if (err)
        goto error;

    for (i = 0; i < tev->nargs; i++)
        if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0)
            goto error;

    ret = strbuf_detach(&buf, NULL);
error:
    strbuf_release(&buf);
    return ret;
}

static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
                      struct perf_probe_point *pp,
                      bool is_kprobe)
{
    struct symbol *sym = NULL;
    struct map *map = NULL;
    u64 addr = tp->address;
    int ret = -ENOENT;

    if (!is_kprobe) {
        map = dso__new_map(tp->module);
        if (!map)
            goto out;
        sym = map__find_symbol(map, addr);
    } else {
        if (tp->symbol && !addr) {
            if (kernel_get_symbol_address_by_name(tp->symbol,
                        &addr, true, false) < 0)
                goto out;
        }
        if (addr) {
            addr += tp->offset;
            sym = machine__find_kernel_symbol(host_machine, addr, &map);
        }
    }

    if (!sym)
        goto out;

    pp->retprobe = tp->retprobe;
    pp->offset = addr - map->unmap_ip(map, sym->start);
    pp->function = strdup(sym->name);
    ret = pp->function ? 0 : -ENOMEM;

out:
    if (map && !is_kprobe) {
        map__put(map);
    }

    return ret;
}

static int convert_to_perf_probe_point(struct probe_trace_point *tp,
                       struct perf_probe_point *pp,
                       bool is_kprobe)
{
    char buf[128];
    int ret;

    ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe);
    if (!ret)
        return 0;
    ret = find_perf_probe_point_from_map(tp, pp, is_kprobe);
    if (!ret)
        return 0;

    pr_debug("Failed to find probe point from both of dwarf and map.\n");

    if (tp->symbol) {
        pp->function = strdup(tp->symbol);
        pp->offset = tp->offset;
    } else {
        ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address);
        if (ret < 0)
            return ret;
        pp->function = strdup(buf);
        pp->offset = 0;
    }
    if (pp->function == NULL)
        return -ENOMEM;

    pp->retprobe = tp->retprobe;

    return 0;
}

static int convert_to_perf_probe_event(struct probe_trace_event *tev,
                   struct perf_probe_event *pev, bool is_kprobe)
{
    struct strbuf buf = STRBUF_INIT;
    int i, ret;

    /* Convert event/group name */
    pev->event = strdup(tev->event);
    pev->group = strdup(tev->group);
    if (pev->event == NULL || pev->group == NULL)
        return -ENOMEM;

    /* Convert trace_point to probe_point */
    ret = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe);
    if (ret < 0)
        return ret;

    /* Convert trace_arg to probe_arg */
    pev->nargs = tev->nargs;
    pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
    if (pev->args == NULL)
        return -ENOMEM;
    for (i = 0; i < tev->nargs && ret >= 0; i++) {
        if (tev->args[i].name)
            pev->args[i].name = strdup(tev->args[i].name);
        else {
            if ((ret = strbuf_init(&buf, 32)) < 0)
                goto error;
            ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
            pev->args[i].name = strbuf_detach(&buf, NULL);
        }
        if (pev->args[i].name == NULL && ret >= 0)
            ret = -ENOMEM;
    }
error:
    if (ret < 0)
        clear_perf_probe_event(pev);

    return ret;
}

void clear_perf_probe_event(struct perf_probe_event *pev)
{
    struct perf_probe_arg_field *field, *next;
    int i;

    free(pev->event);
    free(pev->group);
    free(pev->target);
    clear_perf_probe_point(&pev->point);

    for (i = 0; i < pev->nargs; i++) {
        free(pev->args[i].name);
        free(pev->args[i].var);
        free(pev->args[i].type);
        field = pev->args[i].field;
        while (field) {
            next = field->next;
            zfree(&field->name);
            free(field);
            field = next;
        }
    }
    free(pev->args);
    memset(pev, 0, sizeof(*pev));
}

#define strdup_or_goto(str, label)  \
({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; })

static int perf_probe_point__copy(struct perf_probe_point *dst,
                  struct perf_probe_point *src)
{
    dst->file = strdup_or_goto(src->file, out_err);
    dst->function = strdup_or_goto(src->function, out_err);
    dst->lazy_line = strdup_or_goto(src->lazy_line, out_err);
    dst->line = src->line;
    dst->retprobe = src->retprobe;
    dst->offset = src->offset;
    return 0;

out_err:
    clear_perf_probe_point(dst);
    return -ENOMEM;
}

static int perf_probe_arg__copy(struct perf_probe_arg *dst,
                struct perf_probe_arg *src)
{
    struct perf_probe_arg_field *field, **ppfield;

    dst->name = strdup_or_goto(src->name, out_err);
    dst->var = strdup_or_goto(src->var, out_err);
    dst->type = strdup_or_goto(src->type, out_err);

    field = src->field;
    ppfield = &(dst->field);
    while (field) {
        *ppfield = zalloc(sizeof(*field));
        if (!*ppfield)
            goto out_err;
        (*ppfield)->name = strdup_or_goto(field->name, out_err);
        (*ppfield)->index = field->index;
        (*ppfield)->ref = field->ref;
        field = field->next;
        ppfield = &((*ppfield)->next);
    }
    return 0;
out_err:
    return -ENOMEM;
}

int perf_probe_event__copy(struct perf_probe_event *dst,
               struct perf_probe_event *src)
{
    int i;

    dst->event = strdup_or_goto(src->event, out_err);
    dst->group = strdup_or_goto(src->group, out_err);
    dst->target = strdup_or_goto(src->target, out_err);
    dst->uprobes = src->uprobes;

    if (perf_probe_point__copy(&dst->point, &src->point) < 0)
        goto out_err;

    dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs);
    if (!dst->args)
        goto out_err;
    dst->nargs = src->nargs;

    for (i = 0; i < src->nargs; i++)
        if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0)
            goto out_err;
    return 0;

out_err:
    clear_perf_probe_event(dst);
    return -ENOMEM;
}

void clear_probe_trace_event(struct probe_trace_event *tev)
{
    struct probe_trace_arg_ref *ref, *next;
    int i;

    free(tev->event);
    free(tev->group);
    free(tev->point.symbol);
    free(tev->point.realname);
    free(tev->point.module);
    for (i = 0; i < tev->nargs; i++) {
        free(tev->args[i].name);
        free(tev->args[i].value);
        free(tev->args[i].type);
        ref = tev->args[i].ref;
        while (ref) {
            next = ref->next;
            free(ref);
            ref = next;
        }
    }
    free(tev->args);
    memset(tev, 0, sizeof(*tev));
}

struct kprobe_blacklist_node {
    struct list_head list;
    unsigned long start;
    unsigned long end;
    char *symbol;
};

static void kprobe_blacklist__delete(struct list_head *blacklist)
{
    struct kprobe_blacklist_node *node;

    while (!list_empty(blacklist)) {
        node = list_first_entry(blacklist,
                    struct kprobe_blacklist_node, list);
        list_del(&node->list);
        free(node->symbol);
        free(node);
    }
}

static int kprobe_blacklist__load(struct list_head *blacklist)
{
    struct kprobe_blacklist_node *node;
    const char *__debugfs = debugfs__mountpoint();
    char buf[PATH_MAX], *p;
    FILE *fp;
    int ret;

    if (__debugfs == NULL)
        return -ENOTSUP;

    ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs);
    if (ret < 0)
        return ret;

    fp = fopen(buf, "r");
    if (!fp)
        return -errno;

    ret = 0;
    while (fgets(buf, PATH_MAX, fp)) {
        node = zalloc(sizeof(*node));
        if (!node) {
            ret = -ENOMEM;
            break;
        }
        INIT_LIST_HEAD(&node->list);
        list_add_tail(&node->list, blacklist);
        if (sscanf(buf, "0x%lx-0x%lx", &node->start, &node->end) != 2) {
            ret = -EINVAL;
            break;
        }
        p = strchr(buf, '\t');
        if (p) {
            p++;
            if (p[strlen(p) - 1] == '\n')
                p[strlen(p) - 1] = '\0';
        } else
            p = (char *)"unknown";
        node->symbol = strdup(p);
        if (!node->symbol) {
            ret = -ENOMEM;
            break;
        }
        pr_debug2("Blacklist: 0x%lx-0x%lx, %s\n",
              node->start, node->end, node->symbol);
        ret++;
    }
    if (ret < 0)
        kprobe_blacklist__delete(blacklist);
    fclose(fp);

    return ret;
}

static struct kprobe_blacklist_node *
kprobe_blacklist__find_by_address(struct list_head *blacklist,
                  unsigned long address)
{
    struct kprobe_blacklist_node *node;

    list_for_each_entry(node, blacklist, list) {
        if (node->start <= address && address < node->end)
            return node;
    }

    return NULL;
}

static LIST_HEAD(kprobe_blacklist);

static void kprobe_blacklist__init(void)
{
    if (!list_empty(&kprobe_blacklist))
        return;

    if (kprobe_blacklist__load(&kprobe_blacklist) < 0)
        pr_debug("No kprobe blacklist support, ignored\n");
}

static void kprobe_blacklist__release(void)
{
    kprobe_blacklist__delete(&kprobe_blacklist);
}

static bool kprobe_blacklist__listed(unsigned long address)
{
    return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
}

static int perf_probe_event__sprintf(const char *group, const char *event,
                     struct perf_probe_event *pev,
                     const char *module,
                     struct strbuf *result)
{
    int i, ret;
    char *buf;

    if (asprintf(&buf, "%s:%s", group, event) < 0)
        return -errno;
    ret = strbuf_addf(result, "  %-20s (on ", buf);
    free(buf);
    if (ret)
        return ret;

    /* Synthesize only event probe point */
    buf = synthesize_perf_probe_point(&pev->point);
    if (!buf)
        return -ENOMEM;
    ret = strbuf_addstr(result, buf);
    free(buf);

    if (!ret && module)
        ret = strbuf_addf(result, " in %s", module);

    if (!ret && pev->nargs > 0) {
        ret = strbuf_add(result, " with", 5);
        for (i = 0; !ret && i < pev->nargs; i++) {
            buf = synthesize_perf_probe_arg(&pev->args[i]);
            if (!buf)
                return -ENOMEM;
            ret = strbuf_addf(result, " %s", buf);
            free(buf);
        }
    }
    if (!ret)
        ret = strbuf_addch(result, ')');

    return ret;
}

/* Show an event */
int show_perf_probe_event(const char *group, const char *event,
              struct perf_probe_event *pev,
              const char *module, bool use_stdout)
{
    struct strbuf buf = STRBUF_INIT;
    int ret;

    ret = perf_probe_event__sprintf(group, event, pev, module, &buf);
    if (ret >= 0) {
        if (use_stdout)
            printf("%s\n", buf.buf);
        else
            pr_info("%s\n", buf.buf);
    }
    strbuf_release(&buf);

    return ret;
}

static bool filter_probe_trace_event(struct probe_trace_event *tev,
                     struct strfilter *filter)
{
    char tmp[128];

    /* At first, check the event name itself */
    if (strfilter__compare(filter, tev->event))
        return true;

    /* Next, check the combination of name and group */
    if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0)
        return false;
    return strfilter__compare(filter, tmp);
}

static int __show_perf_probe_events(int fd, bool is_kprobe,
                    struct strfilter *filter)
{
    int ret = 0;
    struct probe_trace_event tev;
    struct perf_probe_event pev;
    struct strlist *rawlist;
    struct str_node *ent;

    memset(&tev, 0, sizeof(tev));
    memset(&pev, 0, sizeof(pev));

    rawlist = probe_file__get_rawlist(fd);
    if (!rawlist)
        return -ENOMEM;

    strlist__for_each_entry(ent, rawlist) {
        ret = parse_probe_trace_command(ent->s, &tev);
        if (ret >= 0) {
            if (!filter_probe_trace_event(&tev, filter))
                goto next;
            ret = convert_to_perf_probe_event(&tev, &pev,
                                is_kprobe);
            if (ret < 0)
                goto next;
            ret = show_perf_probe_event(pev.group, pev.event,
                            &pev, tev.point.module,
                            true);
        }
next:
        clear_perf_probe_event(&pev);
        clear_probe_trace_event(&tev);
        if (ret < 0)
            break;
    }
    strlist__delete(rawlist);
    /* Cleanup cached debuginfo if needed */
    debuginfo_cache__exit();

    return ret;
}

/* List up current perf-probe events */
int show_perf_probe_events(struct strfilter *filter)
{
    int kp_fd, up_fd, ret;

    setup_pager();

    if (probe_conf.cache)
        return probe_cache__show_all_caches(filter);

    ret = init_probe_symbol_maps(false);
    if (ret < 0)
        return ret;

    ret = probe_file__open_both(&kp_fd, &up_fd, 0);
    if (ret < 0)
        return ret;

    if (kp_fd >= 0)
        ret = __show_perf_probe_events(kp_fd, true, filter);
    if (up_fd >= 0 && ret >= 0)
        ret = __show_perf_probe_events(up_fd, false, filter);
    if (kp_fd > 0)
        close(kp_fd);
    if (up_fd > 0)
        close(up_fd);
    exit_probe_symbol_maps();

    return ret;
}

static int get_new_event_name(char *buf, size_t len, const char *base,
                  struct strlist *namelist, bool ret_event,
                  bool allow_suffix)
{
    int i, ret;
    char *p, *nbase;

    if (*base == '.')
        base++;
    nbase = strdup(base);
    if (!nbase)
        return -ENOMEM;

    /* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */
    p = strpbrk(nbase, ".@");
    if (p && p != nbase)
        *p = '\0';

    /* Try no suffix number */
    ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : "");
    if (ret < 0) {
        pr_debug("snprintf() failed: %d\n", ret);
        goto out;
    }
    if (!strlist__has_entry(namelist, buf))
        goto out;

    if (!allow_suffix) {
        pr_warning("Error: event \"%s\" already exists.\n"
               " Hint: Remove existing event by 'perf probe -d'\n"
               "       or force duplicates by 'perf probe -f'\n"
               "       or set 'force=yes' in BPF source.\n",
               buf);
        ret = -EEXIST;
        goto out;
    }

    /* Try to add suffix */
    for (i = 1; i < MAX_EVENT_INDEX; i++) {
        ret = e_snprintf(buf, len, "%s_%d", nbase, i);
        if (ret < 0) {
            pr_debug("snprintf() failed: %d\n", ret);
            goto out;
        }
        if (!strlist__has_entry(namelist, buf))
            break;
    }
    if (i == MAX_EVENT_INDEX) {
        pr_warning("Too many events are on the same function.\n");
        ret = -ERANGE;
    }

out:
    free(nbase);

    /* Final validation */
    if (ret >= 0 && !is_c_func_name(buf)) {
        pr_warning("Internal error: \"%s\" is an invalid event name.\n",
               buf);
        ret = -EINVAL;
    }

    return ret;
}

/* Warn if the current kernel's uprobe implementation is old */
static void warn_uprobe_event_compat(struct probe_trace_event *tev)
{
    int i;
    char *buf = synthesize_probe_trace_command(tev);

    /* Old uprobe event doesn't support memory dereference */
    if (!tev->uprobes || tev->nargs == 0 || !buf)
        goto out;

    for (i = 0; i < tev->nargs; i++)
        if (strglobmatch(tev->args[i].value, "[$@+-]*")) {
            pr_warning("Please upgrade your kernel to at least "
                   "3.14 to have access to feature %s\n",
                   tev->args[i].value);
            break;
        }
out:
    free(buf);
}

/* Set new name from original perf_probe_event and namelist */
static int probe_trace_event__set_name(struct probe_trace_event *tev,
                       struct perf_probe_event *pev,
                       struct strlist *namelist,
                       bool allow_suffix)
{
    const char *event, *group;
    char buf[64];
    int ret;

    /* If probe_event or trace_event already have the name, reuse it */
    if (pev->event && !pev->sdt)
        event = pev->event;
    else if (tev->event)
        event = tev->event;
    else {
        /* Or generate new one from probe point */
        if (pev->point.function &&
            (strncmp(pev->point.function, "0x", 2) != 0) &&
            !strisglob(pev->point.function))
            event = pev->point.function;
        else
            event = tev->point.realname;
    }
    if (pev->group && !pev->sdt)
        group = pev->group;
    else if (tev->group)
        group = tev->group;
    else
        group = PERFPROBE_GROUP;

    /* Get an unused new event name */
    ret = get_new_event_name(buf, 64, event, namelist,
                 tev->point.retprobe, allow_suffix);
    if (ret < 0)
        return ret;

    event = buf;

    tev->event = strdup(event);
    tev->group = strdup(group);
    if (tev->event == NULL || tev->group == NULL)
        return -ENOMEM;

    /* Add added event name to namelist */
    strlist__add(namelist, event);
    return 0;
}

static int __open_probe_file_and_namelist(bool uprobe,
                      struct strlist **namelist)
{
    int fd;

    fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0));
    if (fd < 0)
        return fd;

    /* Get current event names */
    *namelist = probe_file__get_namelist(fd);
    if (!(*namelist)) {
        pr_debug("Failed to get current event list.\n");
        close(fd);
        return -ENOMEM;
    }
    return fd;
}

static int __add_probe_trace_events(struct perf_probe_event *pev,
                     struct probe_trace_event *tevs,
                     int ntevs, bool allow_suffix)
{
    int i, fd[2] = {-1, -1}, up, ret;
    struct probe_trace_event *tev = NULL;
    struct probe_cache *cache = NULL;
    struct strlist *namelist[2] = {NULL, NULL};
    struct nscookie nsc;

    up = pev->uprobes ? 1 : 0;
    fd[up] = __open_probe_file_and_namelist(up, &namelist[up]);
    if (fd[up] < 0)
        return fd[up];

    ret = 0;
    for (i = 0; i < ntevs; i++) {
        tev = &tevs[i];
        up = tev->uprobes ? 1 : 0;
        if (fd[up] == -1) { /* Open the kprobe/uprobe_events */
            fd[up] = __open_probe_file_and_namelist(up,
                                &namelist[up]);
            if (fd[up] < 0)
                goto close_out;
        }
        /* Skip if the symbol is out of .text or blacklisted */
        if (!tev->point.symbol && !pev->uprobes)
            continue;

        /* Set new name for tev (and update namelist) */
        ret = probe_trace_event__set_name(tev, pev, namelist[up],
                          allow_suffix);
        if (ret < 0)
            break;

        nsinfo__mountns_enter(pev->nsi, &nsc);
        ret = probe_file__add_event(fd[up], tev);
        nsinfo__mountns_exit(&nsc);
        if (ret < 0)
            break;

        /*
         * Probes after the first probe which comes from same
         * user input are always allowed to add suffix, because
         * there might be several addresses corresponding to
         * one code line.
         */
        allow_suffix = true;
    }
    if (ret == -EINVAL && pev->uprobes)
        warn_uprobe_event_compat(tev);
    if (ret == 0 && probe_conf.cache) {
        cache = probe_cache__new(pev->target, pev->nsi);
        if (!cache ||
            probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 ||
            probe_cache__commit(cache) < 0)
            pr_warning("Failed to add event to probe cache\n");
        probe_cache__delete(cache);
    }

close_out:
    for (up = 0; up < 2; up++) {
        strlist__delete(namelist[up]);
        if (fd[up] >= 0)
            close(fd[up]);
    }
    return ret;
}

static int find_probe_functions(struct map *map, char *name,
                struct symbol **syms)
{
    int found = 0;
    struct symbol *sym;
    struct rb_node *tmp;
    const char *norm, *ver;
    char *buf = NULL;
    bool cut_version = true;

    if (map__load(map) < 0)
        return 0;

    /* If user gives a version, don't cut off the version from symbols */
    if (strchr(name, '@'))
        cut_version = false;

    map__for_each_symbol(map, sym, tmp) {
        norm = arch__normalize_symbol_name(sym->name);
        if (!norm)
            continue;

        if (cut_version) {
            /* We don't care about default symbol or not */
            ver = strchr(norm, '@');
            if (ver) {
                buf = strndup(norm, ver - norm);
                if (!buf)
                    return -ENOMEM;
                norm = buf;
            }
        }

        if (strglobmatch(norm, name)) {
            found++;
            if (syms && found < probe_conf.max_probes)
                syms[found - 1] = sym;
        }
        if (buf)
            zfree(&buf);
    }

    return found;
}

void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused,
                struct probe_trace_event *tev __maybe_unused,
                struct map *map __maybe_unused,
                struct symbol *sym __maybe_unused) { }

/*
 * Find probe function addresses from map.
 * Return an error or the number of found probe_trace_event
 */
static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
                        struct probe_trace_event **tevs)
{
    struct map *map = NULL;
    struct ref_reloc_sym *reloc_sym = NULL;
    struct symbol *sym;
    struct symbol **syms = NULL;
    struct probe_trace_event *tev;
    struct perf_probe_point *pp = &pev->point;
    struct probe_trace_point *tp;
    int num_matched_functions;
    int ret, i, j, skipped = 0;
    char *mod_name;

    map = get_target_map(pev->target, pev->nsi, pev->uprobes);
    if (!map) {
        ret = -EINVAL;
        goto out;
    }

    syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes);
    if (!syms) {
        ret = -ENOMEM;
        goto out;
    }

    /*
     * Load matched symbols: Since the different local symbols may have
     * same name but different addresses, this lists all the symbols.
     */
    num_matched_functions = find_probe_functions(map, pp->function, syms);
    if (num_matched_functions <= 0) {
        pr_err("Failed to find symbol %s in %s\n", pp->function,
            pev->target ? : "kernel");
        ret = -ENOENT;
        goto out;
    } else if (num_matched_functions > probe_conf.max_probes) {
        pr_err("Too many functions matched in %s\n",
            pev->target ? : "kernel");
        ret = -E2BIG;
        goto out;
    }

    /* Note that the symbols in the kmodule are not relocated */
    if (!pev->uprobes && !pev->target &&
            (!pp->retprobe || kretprobe_offset_is_supported())) {
        reloc_sym = kernel_get_ref_reloc_sym();
        if (!reloc_sym) {
            pr_warning("Relocated base symbol is not found!\n");
            ret = -EINVAL;
            goto out;
        }
    }

    /* Setup result trace-probe-events */
    *tevs = zalloc(sizeof(*tev) * num_matched_functions);
    if (!*tevs) {
        ret = -ENOMEM;
        goto out;
    }

    ret = 0;

    for (j = 0; j < num_matched_functions; j++) {
        sym = syms[j];

        tev = (*tevs) + ret;
        tp = &tev->point;
        if (ret == num_matched_functions) {
            pr_warning("Too many symbols are listed. Skip it.\n");
            break;
        }
        ret++;

        if (pp->offset > sym->end - sym->start) {
            pr_warning("Offset %ld is bigger than the size of %s\n",
                   pp->offset, sym->name);
            ret = -ENOENT;
            goto err_out;
        }
        /* Add one probe point */
        tp->address = map->unmap_ip(map, sym->start) + pp->offset;

        /* Check the kprobe (not in module) is within .text  */
        if (!pev->uprobes && !pev->target &&
            kprobe_warn_out_range(sym->name, tp->address)) {
            tp->symbol = NULL;  /* Skip it */
            skipped++;
        } else if (reloc_sym) {
            tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out);
            tp->offset = tp->address - reloc_sym->addr;
        } else {
            tp->symbol = strdup_or_goto(sym->name, nomem_out);
            tp->offset = pp->offset;
        }
        tp->realname = strdup_or_goto(sym->name, nomem_out);

        tp->retprobe = pp->retprobe;
        if (pev->target) {
            if (pev->uprobes) {
                tev->point.module = strdup_or_goto(pev->target,
                                   nomem_out);
            } else {
                mod_name = find_module_name(pev->target);
                tev->point.module =
                    strdup(mod_name ? mod_name : pev->target);
                free(mod_name);
                if (!tev->point.module)
                    goto nomem_out;
            }
        }
        tev->uprobes = pev->uprobes;
        tev->nargs = pev->nargs;
        if (tev->nargs) {
            tev->args = zalloc(sizeof(struct probe_trace_arg) *
                       tev->nargs);
            if (tev->args == NULL)
                goto nomem_out;
        }
        for (i = 0; i < tev->nargs; i++) {
            if (pev->args[i].name)
                tev->args[i].name =
                    strdup_or_goto(pev->args[i].name,
                            nomem_out);

            tev->args[i].value = strdup_or_goto(pev->args[i].var,
                                nomem_out);
            if (pev->args[i].type)
                tev->args[i].type =
                    strdup_or_goto(pev->args[i].type,
                            nomem_out);
        }
        arch__fix_tev_from_maps(pev, tev, map, sym);
    }
    if (ret == skipped) {
        ret = -ENOENT;
        goto err_out;
    }

out:
    map__put(map);
    free(syms);
    return ret;

nomem_out:
    ret = -ENOMEM;
err_out:
    clear_probe_trace_events(*tevs, num_matched_functions);
    zfree(tevs);
    goto out;
}

static int try_to_find_absolute_address(struct perf_probe_event *pev,
                    struct probe_trace_event **tevs)
{
    struct perf_probe_point *pp = &pev->point;
    struct probe_trace_event *tev;
    struct probe_trace_point *tp;
    int i, err;

    if (!(pev->point.function && !strncmp(pev->point.function, "0x", 2)))
        return -EINVAL;
    if (perf_probe_event_need_dwarf(pev))
        return -EINVAL;

    /*
     * This is 'perf probe /lib/libc.so 0xabcd'. Try to probe at
     * absolute address.
     *
     * Only one tev can be generated by this.
     */
    *tevs = zalloc(sizeof(*tev));
    if (!*tevs)
        return -ENOMEM;

    tev = *tevs;
    tp = &tev->point;

    /*
     * Don't use tp->offset, use address directly, because
     * in synthesize_probe_trace_command() address cannot be
     * zero.
     */
    tp->address = pev->point.abs_address;
    tp->retprobe = pp->retprobe;
    tev->uprobes = pev->uprobes;

    err = -ENOMEM;
    /*
     * Give it a '0x' leading symbol name.
     * In __add_probe_trace_events, a NULL symbol is interpreted as
     * invalud.
     */
    if (asprintf(&tp->symbol, "0x%lx", tp->address) < 0)
        goto errout;

    /* For kprobe, check range */
    if ((!tev->uprobes) &&
        (kprobe_warn_out_range(tev->point.symbol,
                   tev->point.address))) {
        err = -EACCES;
        goto errout;
    }

    if (asprintf(&tp->realname, "abs_%lx", tp->address) < 0)
        goto errout;

    if (pev->target) {
        tp->module = strdup(pev->target);
        if (!tp->module)
            goto errout;
    }

    if (tev->group) {
        tev->group = strdup(pev->group);
        if (!tev->group)
            goto errout;
    }

    if (pev->event) {
        tev->event = strdup(pev->event);
        if (!tev->event)
            goto errout;
    }

    tev->nargs = pev->nargs;
    tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
    if (!tev->args)
        goto errout;

    for (i = 0; i < tev->nargs; i++)
        copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]);

    return 1;

errout:
    clear_probe_trace_events(*tevs, 1);
    *tevs = NULL;
    return err;
}

/* Concatinate two arrays */
static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b)
{
    void *ret;

    ret = malloc(sz_a + sz_b);
    if (ret) {
        memcpy(ret, a, sz_a);
        memcpy(ret + sz_a, b, sz_b);
    }
    return ret;
}

static int
concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs,
              struct probe_trace_event **tevs2, int ntevs2)
{
    struct probe_trace_event *new_tevs;
    int ret = 0;

    if (*ntevs == 0) {
        *tevs = *tevs2;
        *ntevs = ntevs2;
        *tevs2 = NULL;
        return 0;
    }

    if (*ntevs + ntevs2 > probe_conf.max_probes)
        ret = -E2BIG;
    else {
        /* Concatinate the array of probe_trace_event */
        new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs),
                  *tevs2, ntevs2 * sizeof(**tevs2));
        if (!new_tevs)
            ret = -ENOMEM;
        else {
            free(*tevs);
            *tevs = new_tevs;
            *ntevs += ntevs2;
        }
    }
    if (ret < 0)
        clear_probe_trace_events(*tevs2, ntevs2);
    zfree(tevs2);

    return ret;
}

/*
 * Try to find probe_trace_event from given probe caches. Return the number
 * of cached events found, if an error occurs return the error.
 */
static int find_cached_events(struct perf_probe_event *pev,
                  struct probe_trace_event **tevs,
                  const char *target)
{
    struct probe_cache *cache;
    struct probe_cache_entry *entry;
    struct probe_trace_event *tmp_tevs = NULL;
    int ntevs = 0;
    int ret = 0;

    cache = probe_cache__new(target, pev->nsi);
    /* Return 0 ("not found") if the target has no probe cache. */
    if (!cache)
        return 0;

    for_each_probe_cache_entry(entry, cache) {
        /* Skip the cache entry which has no name */
        if (!entry->pev.event || !entry->pev.group)
            continue;
        if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) &&
            strglobmatch(entry->pev.event, pev->event)) {
            ret = probe_cache_entry__get_event(entry, &tmp_tevs);
            if (ret > 0)
                ret = concat_probe_trace_events(tevs, &ntevs,
                                &tmp_tevs, ret);
            if (ret < 0)
                break;
        }
    }
    probe_cache__delete(cache);
    if (ret < 0) {
        clear_probe_trace_events(*tevs, ntevs);
        zfree(tevs);
    } else {
        ret = ntevs;
        if (ntevs > 0 && target && target[0] == '/')
            pev->uprobes = true;
    }

    return ret;
}

/* Try to find probe_trace_event from all probe caches */
static int find_cached_events_all(struct perf_probe_event *pev,
                   struct probe_trace_event **tevs)
{
    struct probe_trace_event *tmp_tevs = NULL;
    struct strlist *bidlist;
    struct str_node *nd;
    char *pathname;
    int ntevs = 0;
    int ret;

    /* Get the buildid list of all valid caches */
    bidlist = build_id_cache__list_all(true);
    if (!bidlist) {
        ret = -errno;
        pr_debug("Failed to get buildids: %d\n", ret);
        return ret;
    }

    ret = 0;
    strlist__for_each_entry(nd, bidlist) {
        pathname = build_id_cache__origname(nd->s);
        ret = find_cached_events(pev, &tmp_tevs, pathname);
        /* In the case of cnt == 0, we just skip it */
        if (ret > 0)
            ret = concat_probe_trace_events(tevs, &ntevs,
                            &tmp_tevs, ret);
        free(pathname);
        if (ret < 0)
            break;
    }
    strlist__delete(bidlist);

    if (ret < 0) {
        clear_probe_trace_events(*tevs, ntevs);
        zfree(tevs);
    } else
        ret = ntevs;

    return ret;
}

static int find_probe_trace_events_from_cache(struct perf_probe_event *pev,
                          struct probe_trace_event **tevs)
{
    struct probe_cache *cache;
    struct probe_cache_entry *entry;
    struct probe_trace_event *tev;
    struct str_node *node;
    int ret, i;

    if (pev->sdt) {
        /* For SDT/cached events, we use special search functions */
        if (!pev->target)
            return find_cached_events_all(pev, tevs);
        else
            return find_cached_events(pev, tevs, pev->target);
    }
    cache = probe_cache__new(pev->target, pev->nsi);
    if (!cache)
        return 0;

    entry = probe_cache__find(cache, pev);
    if (!entry) {
        /* SDT must be in the cache */
        ret = pev->sdt ? -ENOENT : 0;
        goto out;
    }

    ret = strlist__nr_entries(entry->tevlist);
    if (ret > probe_conf.max_probes) {
        pr_debug("Too many entries matched in the cache of %s\n",
             pev->target ? : "kernel");
        ret = -E2BIG;
        goto out;
    }

    *tevs = zalloc(ret * sizeof(*tev));
    if (!*tevs) {
        ret = -ENOMEM;
        goto out;
    }

    i = 0;
    strlist__for_each_entry(node, entry->tevlist) {
        tev = &(*tevs)[i++];
        ret = parse_probe_trace_command(node->s, tev);
        if (ret < 0)
            goto out;
        /* Set the uprobes attribute as same as original */
        tev->uprobes = pev->uprobes;
    }
    ret = i;

out:
    probe_cache__delete(cache);
    return ret;
}

static int convert_to_probe_trace_events(struct perf_probe_event *pev,
                     struct probe_trace_event **tevs)
{
    int ret;

    if (!pev->group && !pev->sdt) {
        /* Set group name if not given */
        if (!pev->uprobes) {
            pev->group = strdup(PERFPROBE_GROUP);
            ret = pev->group ? 0 : -ENOMEM;
        } else
            ret = convert_exec_to_group(pev->target, &pev->group);
        if (ret != 0) {
            pr_warning("Failed to make a group name.\n");
            return ret;
        }
    }

    ret = try_to_find_absolute_address(pev, tevs);
    if (ret > 0)
        return ret;

    /* At first, we need to lookup cache entry */
    ret = find_probe_trace_events_from_cache(pev, tevs);
    if (ret > 0 || pev->sdt)    /* SDT can be found only in the cache */
        return ret == 0 ? -ENOENT : ret; /* Found in probe cache */

    /* Convert perf_probe_event with debuginfo */
    ret = try_to_find_probe_trace_events(pev, tevs);
    if (ret != 0)
        return ret; /* Found in debuginfo or got an error */

    return find_probe_trace_events_from_map(pev, tevs);
}

int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs)
{
    int i, ret;

    /* Loop 1: convert all events */
    for (i = 0; i < npevs; i++) {
        /* Init kprobe blacklist if needed */
        if (!pevs[i].uprobes)
            kprobe_blacklist__init();
        /* Convert with or without debuginfo */
        ret  = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs);
        if (ret < 0)
            return ret;
        pevs[i].ntevs = ret;
    }
    /* This just release blacklist only if allocated */
    kprobe_blacklist__release();

    return 0;
}

static int show_probe_trace_event(struct probe_trace_event *tev)
{
    char *buf = synthesize_probe_trace_command(tev);

    if (!buf) {
        pr_debug("Failed to synthesize probe trace event.\n");
        return -EINVAL;
    }

    /* Showing definition always go stdout */
    printf("%s\n", buf);
    free(buf);

    return 0;
}

int show_probe_trace_events(struct perf_probe_event *pevs, int npevs)
{
    struct strlist *namelist = strlist__new(NULL, NULL);
    struct probe_trace_event *tev;
    struct perf_probe_event *pev;
    int i, j, ret = 0;

    if (!namelist)
        return -ENOMEM;

    for (j = 0; j < npevs && !ret; j++) {
        pev = &pevs[j];
        for (i = 0; i < pev->ntevs && !ret; i++) {
            tev = &pev->tevs[i];
            /* Skip if the symbol is out of .text or blacklisted */
            if (!tev->point.symbol && !pev->uprobes)
                continue;

            /* Set new name for tev (and update namelist) */
            ret = probe_trace_event__set_name(tev, pev,
                              namelist, true);
            if (!ret)
                ret = show_probe_trace_event(tev);
        }
    }
    strlist__delete(namelist);

    return ret;
}

int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)
{
    int i, ret = 0;

    /* Loop 2: add all events */
    for (i = 0; i < npevs; i++) {
        ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs,
                           pevs[i].ntevs,
                           probe_conf.force_add);
        if (ret < 0)
            break;
    }
    return ret;
}

void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs)
{
    int i, j;
    struct perf_probe_event *pev;

    /* Loop 3: cleanup and free trace events  */
    for (i = 0; i < npevs; i++) {
        pev = &pevs[i];
        for (j = 0; j < pevs[i].ntevs; j++)
            clear_probe_trace_event(&pevs[i].tevs[j]);
        zfree(&pevs[i].tevs);
        pevs[i].ntevs = 0;
        nsinfo__zput(pev->nsi);
        clear_perf_probe_event(&pevs[i]);
    }
}

int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
{
    int ret;

    ret = init_probe_symbol_maps(pevs->uprobes);
    if (ret < 0)
        return ret;

    ret = convert_perf_probe_events(pevs, npevs);
    if (ret == 0)
        ret = apply_perf_probe_events(pevs, npevs);

    cleanup_perf_probe_events(pevs, npevs);

    exit_probe_symbol_maps();
    return ret;
}

int del_perf_probe_events(struct strfilter *filter)
{
    int ret, ret2, ufd = -1, kfd = -1;
    char *str = strfilter__string(filter);

    if (!str)
        return -EINVAL;

    /* Get current event names */
    ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
    if (ret < 0)
        goto out;

    ret = probe_file__del_events(kfd, filter);
    if (ret < 0 && ret != -ENOENT)
        goto error;

    ret2 = probe_file__del_events(ufd, filter);
    if (ret2 < 0 && ret2 != -ENOENT) {
        ret = ret2;
        goto error;
    }
    ret = 0;

error:
    if (kfd >= 0)
        close(kfd);
    if (ufd >= 0)
        close(ufd);
out:
    free(str);

    return ret;
}

int show_available_funcs(const char *target, struct nsinfo *nsi,
             struct strfilter *_filter, bool user)
{
        struct rb_node *nd;
    struct map *map;
    int ret;

    ret = init_probe_symbol_maps(user);
    if (ret < 0)
        return ret;

    /* Get a symbol map */
    map = get_target_map(target, nsi, user);
    if (!map) {
        pr_err("Failed to get a map for %s\n", (target) ? : "kernel");
        return -EINVAL;
    }

    ret = map__load(map);
    if (ret) {
        if (ret == -2) {
            char *str = strfilter__string(_filter);
            pr_err("Failed to find symbols matched to \"%s\"\n",
                   str);
            free(str);
        } else
            pr_err("Failed to load symbols in %s\n",
                   (target) ? : "kernel");
        goto end;
    }
    if (!dso__sorted_by_name(map->dso))
        dso__sort_by_name(map->dso);

    /* Show all (filtered) symbols */
    setup_pager();

    for (nd = rb_first(&map->dso->symbol_names); nd; nd = rb_next(nd)) {
        struct symbol_name_rb_node *pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);

        if (strfilter__compare(_filter, pos->sym.name))
            printf("%s\n", pos->sym.name);
    }
end:
    map__put(map);
    exit_probe_symbol_maps();

    return ret;
}

int copy_to_probe_trace_arg(struct probe_trace_arg *tvar,
                struct perf_probe_arg *pvar)
{
    tvar->value = strdup(pvar->var);
    if (tvar->value == NULL)
        return -ENOMEM;
    if (pvar->type) {
        tvar->type = strdup(pvar->type);
        if (tvar->type == NULL)
            return -ENOMEM;
    }
    if (pvar->name) {
        tvar->name = strdup(pvar->name);
        if (tvar->name == NULL)
            return -ENOMEM;
    } else
        tvar->name = NULL;
    return 0;
}