perf: Add perf probe subcommand, a kprobe-event setup helper

Add perf probe subcommand that implements a kprobe-event setup helper
to the perf command.
This allows user to define kprobe events using C expressions (C line
numbers, C function names, and C local variables).

Usage
-----
 perf probe [<options>] -P 'PROBEDEF' [-P 'PROBEDEF' ...]

    -k, --vmlinux <file>  vmlinux/module pathname
    -P, --probe <p|r:[GRP/]NAME FUNC[+OFFS][@SRC]|@SRC:LINE [ARG ...]>
                          probe point definition, where
		p:	kprobe probe
		r:	kretprobe probe
		GRP:	Group name (optional)
		NAME:	Event name
		FUNC:	Function name
		OFFS:	Offset from function entry (in byte)
		SRC:	Source code path
		LINE:	Line number
		ARG:	Probe argument (local variable name or
			kprobe-tracer argument format is supported.)

Changes in v4:
 - Add _GNU_SOURCE macro for strndup().

Changes in v3:
 - Remove -r option because perf always be used for online kernel.
 - Check malloc/calloc results.

Changes in v2:
 - Check synthesized string length.
 - Rename perf kprobe to perf probe.
 - Use spaces for separator and update usage comment.
 - Check error paths in parse_probepoint().
 - Check optimized-out variables.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
LKML-Reference: <20091008211737.29299.14784.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

1 files changed, 690 insertions, 0 deletions

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
new file mode 100644
index 000000000000..ec6f53f29e00
--- /dev/null
+++ b/tools/perf/util/probe-finder.c
@@ -0,0 +1,690 @@
+/*
+ * probe-finder.c : C expression to kprobe event 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 <sys/utsname.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <ctype.h>
+#include "probe-finder.h"
+
+
+/* Dwarf_Die Linkage to parent Die */
+struct die_link {
+        struct die_link *parent;        /* Parent die */
+        Dwarf_Die die;                  /* Current die */
+};
+
+static Dwarf_Debug __dw_debug;
+static Dwarf_Error __dw_error;
+
+static void msg_exit(int ret, const char *fmt, ...)
+{
+        va_list ap;
+
+        va_start(ap, fmt);
+        fprintf(stderr, "Error:  ");
+        vfprintf(stderr, fmt, ap);
+        va_end(ap);
+
+        fprintf(stderr, "\n");
+        exit(ret);
+}
+
+
+/*
+ * Generic dwarf analysis helpers
+ */
+
+#define X86_32_MAX_REGS 8
+const char *x86_32_regs_table[X86_32_MAX_REGS] = {
+        "%ax",
+        "%cx",
+        "%dx",
+        "%bx",
+        "$stack",       /* Stack address instead of %sp */
+        "%bp",
+        "%si",
+        "%di",
+};
+
+#define X86_64_MAX_REGS 16
+const char *x86_64_regs_table[X86_64_MAX_REGS] = {
+        "%ax",
+        "%dx",
+        "%cx",
+        "%bx",
+        "%si",
+        "%di",
+        "%bp",
+        "%sp",
+        "%r8",
+        "%r9",
+        "%r10",
+        "%r11",
+        "%r12",
+        "%r13",
+        "%r14",
+        "%r15",
+};
+
+/* TODO: switching by dwarf address size */
+#ifdef __x86_64__
+#define ARCH_MAX_REGS X86_64_MAX_REGS
+#define arch_regs_table x86_64_regs_table
+#else
+#define ARCH_MAX_REGS X86_32_MAX_REGS
+#define arch_regs_table x86_32_regs_table
+#endif
+
+/* Return architecture dependent register string (for kprobe-tracer) */
+static const char *get_arch_regstr(unsigned int n)
+{
+        return (n <= ARCH_MAX_REGS) ? arch_regs_table[n] : NULL;
+}
+
+/*
+ * Compare the tail of two strings.
+ * Return 0 if whole of either string is same as another's tail part.
+ */
+static int strtailcmp(const char *s1, const char *s2)
+{
+        int i1 = strlen(s1);
+        int i2 = strlen(s2);
+        while (--i1 > 0 && --i2 > 0) {
+                if (s1[i1] != s2[i2])
+                        return s1[i1] - s2[i2];
+        }
+        return 0;
+}
+
+/* Find the fileno of the target file. */
+static Dwarf_Unsigned die_get_fileno(Dwarf_Die cu_die, const char *fname)
+{
+        Dwarf_Signed cnt, i;
+        Dwarf_Unsigned found = 0;
+        char **srcs;
+        int ret;
+
+        if (!fname)
+                return 0;
+
+        ret = dwarf_srcfiles(cu_die, &srcs, &cnt, &__dw_error);
+        if (ret == DW_DLV_OK) {
+                for (i = 0; i < cnt && !found; i++) {
+                        if (strtailcmp(srcs[i], fname) == 0)
+                                found = i + 1;
+                        dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING);
+                }
+                for (; i < cnt; i++)
+                        dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING);
+                dwarf_dealloc(__dw_debug, srcs, DW_DLA_LIST);
+        }
+        if (found)
+                debug("found fno: %d\n", (int)found);
+        return found;
+}
+
+/* Compare diename and tname */
+static int die_compare_name(Dwarf_Die die, const char *tname)
+{
+        char *name;
+        int ret;
+        ret = dwarf_diename(die, &name, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (ret == DW_DLV_OK) {
+                ret = strcmp(tname, name);
+                dwarf_dealloc(__dw_debug, name, DW_DLA_STRING);
+        } else
+                ret = -1;
+        return ret;
+}
+
+/* Check the address is in the subprogram(function). */
+static int die_within_subprogram(Dwarf_Die sp_die, Dwarf_Addr addr,
+                                 Dwarf_Signed *offs)
+{
+        Dwarf_Addr lopc, hipc;
+        int ret;
+
+        /* TODO: check ranges */
+        ret = dwarf_lowpc(sp_die, &lopc, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (ret == DW_DLV_NO_ENTRY)
+                return 0;
+        ret = dwarf_highpc(sp_die, &hipc, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        if (lopc <= addr && addr < hipc) {
+                *offs = addr - lopc;
+                return 1;
+        } else
+                return 0;
+}
+
+/* Check the die is inlined function */
+static Dwarf_Bool die_inlined_subprogram(Dwarf_Die die)
+{
+        /* TODO: check strictly */
+        Dwarf_Bool inl;
+        int ret;
+
+        ret = dwarf_hasattr(die, DW_AT_inline, &inl, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        return inl;
+}
+
+/* Get the offset of abstruct_origin */
+static Dwarf_Off die_get_abstract_origin(Dwarf_Die die)
+{
+        Dwarf_Attribute attr;
+        Dwarf_Off cu_offs;
+        int ret;
+
+        ret = dwarf_attr(die, DW_AT_abstract_origin, &attr, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        ret = dwarf_formref(attr, &cu_offs, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
+        return cu_offs;
+}
+
+/* Get entry pc(or low pc, 1st entry of ranges)  of the die */
+static Dwarf_Addr die_get_entrypc(Dwarf_Die die)
+{
+        Dwarf_Attribute attr;
+        Dwarf_Addr addr;
+        Dwarf_Off offs;
+        Dwarf_Ranges *ranges;
+        Dwarf_Signed cnt;
+        int ret;
+
+        /* Try to get entry pc */
+        ret = dwarf_attr(die, DW_AT_entry_pc, &attr, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (ret == DW_DLV_OK) {
+                ret = dwarf_formaddr(attr, &addr, &__dw_error);
+                ERR_IF(ret != DW_DLV_OK);
+                dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
+                return addr;
+        }
+
+        /* Try to get low pc */
+        ret = dwarf_lowpc(die, &addr, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (ret == DW_DLV_OK)
+                return addr;
+
+        /* Try to get ranges */
+        ret = dwarf_attr(die, DW_AT_ranges, &attr, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        ret = dwarf_formref(attr, &offs, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        ret = dwarf_get_ranges(__dw_debug, offs, &ranges, &cnt, NULL,
+                                &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        addr = ranges[0].dwr_addr1;
+        dwarf_ranges_dealloc(__dw_debug, ranges, cnt);
+        return addr;
+}
+
+/*
+ * Search a Die from Die tree.
+ * Note: cur_link->die should be deallocated in this function.
+ */
+static int __search_die_tree(struct die_link *cur_link,
+                             int (*die_cb)(struct die_link *, void *),
+                             void *data)
+{
+        Dwarf_Die new_die;
+        struct die_link new_link;
+        int ret;
+
+        if (!die_cb)
+                return 0;
+
+        /* Check current die */
+        while (!(ret = die_cb(cur_link, data))) {
+                /* Check child die */
+                ret = dwarf_child(cur_link->die, &new_die, &__dw_error);
+                ERR_IF(ret == DW_DLV_ERROR);
+                if (ret == DW_DLV_OK) {
+                        new_link.parent = cur_link;
+                        new_link.die = new_die;
+                        ret = __search_die_tree(&new_link, die_cb, data);
+                        if (ret)
+                                break;
+                }
+
+                /* Move to next sibling */
+                ret = dwarf_siblingof(__dw_debug, cur_link->die, &new_die,
+                                      &__dw_error);
+                ERR_IF(ret == DW_DLV_ERROR);
+                dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE);
+                cur_link->die = new_die;
+                if (ret == DW_DLV_NO_ENTRY)
+                        return 0;
+        }
+        dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE);
+        return ret;
+}
+
+/* Search a die in its children's die tree */
+static int search_die_from_children(Dwarf_Die parent_die,
+                                    int (*die_cb)(struct die_link *, void *),
+                                    void *data)
+{
+        struct die_link new_link;
+        int ret;
+
+        new_link.parent = NULL;
+        ret = dwarf_child(parent_die, &new_link.die, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (ret == DW_DLV_OK)
+                return __search_die_tree(&new_link, die_cb, data);
+        else
+                return 0;
+}
+
+/* Find a locdesc corresponding to the address */
+static int attr_get_locdesc(Dwarf_Attribute attr, Dwarf_Locdesc *desc,
+                            Dwarf_Addr addr)
+{
+        Dwarf_Signed lcnt;
+        Dwarf_Locdesc **llbuf;
+        int ret, i;
+
+        ret = dwarf_loclist_n(attr, &llbuf, &lcnt, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        ret = DW_DLV_NO_ENTRY;
+        for (i = 0; i < lcnt; ++i) {
+                if (llbuf[i]->ld_lopc <= addr &&
+                    llbuf[i]->ld_hipc > addr) {
+                        memcpy(desc, llbuf[i], sizeof(Dwarf_Locdesc));
+                        desc->ld_s =
+                                malloc(sizeof(Dwarf_Loc) * llbuf[i]->ld_cents);
+                        ERR_IF(desc->ld_s == NULL);
+                        memcpy(desc->ld_s, llbuf[i]->ld_s,
+                                sizeof(Dwarf_Loc) * llbuf[i]->ld_cents);
+                        ret = DW_DLV_OK;
+                        break;
+                }
+                dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK);
+                dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC);
+        }
+        /* Releasing loop */
+        for (; i < lcnt; ++i) {
+                dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK);
+                dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC);
+        }
+        dwarf_dealloc(__dw_debug, llbuf, DW_DLA_LIST);
+        return ret;
+}
+
+/*
+ * Probe finder related functions
+ */
+
+/* Show a location */
+static void show_location(Dwarf_Loc *loc, struct probe_finder *pf)
+{
+        Dwarf_Small op;
+        Dwarf_Unsigned regn;
+        Dwarf_Signed offs;
+        int deref = 0, ret;
+        const char *regs;
+
+        op = loc->lr_atom;
+
+        /* If this is based on frame buffer, set the offset */
+        if (op == DW_OP_fbreg) {
+                deref = 1;
+                offs = (Dwarf_Signed)loc->lr_number;
+                op = pf->fbloc.ld_s[0].lr_atom;
+                loc = &pf->fbloc.ld_s[0];
+        } else
+                offs = 0;
+
+        if (op >= DW_OP_breg0 && op <= DW_OP_breg31) {
+                regn = op - DW_OP_breg0;
+                offs += (Dwarf_Signed)loc->lr_number;
+                deref = 1;
+        } else if (op >= DW_OP_reg0 && op <= DW_OP_reg31) {
+                regn = op - DW_OP_reg0;
+        } else if (op == DW_OP_bregx) {
+                regn = loc->lr_number;
+                offs += (Dwarf_Signed)loc->lr_number2;
+                deref = 1;
+        } else if (op == DW_OP_regx) {
+                regn = loc->lr_number;
+        } else
+                msg_exit(-EINVAL, "Dwarf_OP %d is not supported.\n", op);
+
+        regs = get_arch_regstr(regn);
+        if (!regs)
+                msg_exit(-EINVAL, "%lld exceeds max register number.\n", regn);
+
+        if (deref)
+                ret = snprintf(pf->buf, pf->len,
+                                 " %s=%+lld(%s)", pf->var, offs, regs);
+        else
+                ret = snprintf(pf->buf, pf->len, " %s=%s", pf->var, regs);
+        ERR_IF(ret < 0);
+        ERR_IF(ret >= pf->len);
+}
+
+/* Show a variables in kprobe event format */
+static void show_variable(Dwarf_Die vr_die, struct probe_finder *pf)
+{
+        Dwarf_Attribute attr;
+        Dwarf_Locdesc ld;
+        int ret;
+
+        ret = dwarf_attr(vr_die, DW_AT_location, &attr, &__dw_error);
+        if (ret != DW_DLV_OK)
+                goto error;
+        ret = attr_get_locdesc(attr, &ld, (pf->addr - pf->cu_base));
+        if (ret != DW_DLV_OK)
+                goto error;
+        /* TODO? */
+        ERR_IF(ld.ld_cents != 1);
+        show_location(&ld.ld_s[0], pf);
+        free(ld.ld_s);
+        dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
+        return ;
+error:
+        msg_exit(-1, "Failed to find the location of %s at this address.\n"
+                 " Perhaps, it was optimized out.\n", pf->var);
+}
+
+static int variable_callback(struct die_link *dlink, void *data)
+{
+        struct probe_finder *pf = (struct probe_finder *)data;
+        Dwarf_Half tag;
+        int ret;
+
+        ret = dwarf_tag(dlink->die, &tag, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if ((tag == DW_TAG_formal_parameter ||
+             tag == DW_TAG_variable) &&
+            (die_compare_name(dlink->die, pf->var) == 0)) {
+                show_variable(dlink->die, pf);
+                return 1;
+        }
+        /* TODO: Support struct members and arrays */
+        return 0;
+}
+
+/* Find a variable in a subprogram die */
+static void find_variable(Dwarf_Die sp_die, struct probe_finder *pf)
+{
+        int ret;
+
+        if (!is_c_varname(pf->var)) {
+                /* Output raw parameters */
+                ret = snprintf(pf->buf, pf->len, " %s", pf->var);
+                ERR_IF(ret < 0);
+                ERR_IF(ret >= pf->len);
+                return ;
+        }
+
+        debug("Searching '%s' variable in context.\n", pf->var);
+        /* Search child die for local variables and parameters. */
+        ret = search_die_from_children(sp_die, variable_callback, pf);
+        if (!ret)
+                msg_exit(-1, "Failed to find '%s' in this function.\n",
+                         pf->var);
+}
+
+/* Get a frame base on the address */
+static void get_current_frame_base(Dwarf_Die sp_die, struct probe_finder *pf)
+{
+        Dwarf_Attribute attr;
+        int ret;
+
+        ret = dwarf_attr(sp_die, DW_AT_frame_base, &attr, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+        ret = attr_get_locdesc(attr, &pf->fbloc, (pf->addr - pf->cu_base));
+        ERR_IF(ret != DW_DLV_OK);
+        dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR);
+}
+
+static void free_current_frame_base(struct probe_finder *pf)
+{
+        free(pf->fbloc.ld_s);
+        memset(&pf->fbloc, 0, sizeof(Dwarf_Locdesc));
+}
+
+/* Show a probe point to output buffer */
+static void show_probepoint(Dwarf_Die sp_die, Dwarf_Signed offs,
+                            struct probe_finder *pf)
+{
+        struct probe_point *pp = pf->pp;
+        char *name;
+        char tmp[MAX_PROBE_BUFFER];
+        int ret, i, len;
+
+        /* Output name of probe point */
+        ret = dwarf_diename(sp_die, &name, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (ret == DW_DLV_OK) {
+                ret = snprintf(tmp, MAX_PROBE_BUFFER, "%s+%u", name,
+                                (unsigned int)offs);
+                dwarf_dealloc(__dw_debug, name, DW_DLA_STRING);
+        } else {
+                /* This function has no name. */
+                ret = snprintf(tmp, MAX_PROBE_BUFFER, "0x%llx", pf->addr);
+        }
+        ERR_IF(ret < 0);
+        ERR_IF(ret >= MAX_PROBE_BUFFER);
+        len = ret;
+
+        /* Find each argument */
+        get_current_frame_base(sp_die, pf);
+        for (i = 0; i < pp->nr_args; i++) {
+                pf->var = pp->args[i];
+                pf->buf = &tmp[len];
+                pf->len = MAX_PROBE_BUFFER - len;
+                find_variable(sp_die, pf);
+                len += strlen(pf->buf);
+        }
+        free_current_frame_base(pf);
+
+        pp->probes[pp->found] = strdup(tmp);
+        pp->found++;
+}
+
+static int probeaddr_callback(struct die_link *dlink, void *data)
+{
+        struct probe_finder *pf = (struct probe_finder *)data;
+        Dwarf_Half tag;
+        Dwarf_Signed offs;
+        int ret;
+
+        ret = dwarf_tag(dlink->die, &tag, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        /* Check the address is in this subprogram */
+        if (tag == DW_TAG_subprogram &&
+            die_within_subprogram(dlink->die, pf->addr, &offs)) {
+                show_probepoint(dlink->die, offs, pf);
+                return 1;
+        }
+        return 0;
+}
+
+/* Find probe point from its line number */
+static void find_by_line(Dwarf_Die cu_die, struct probe_finder *pf)
+{
+        struct probe_point *pp = pf->pp;
+        Dwarf_Signed cnt, i;
+        Dwarf_Line *lines;
+        Dwarf_Unsigned lineno = 0;
+        Dwarf_Addr addr;
+        Dwarf_Unsigned fno;
+        int ret;
+
+        ret = dwarf_srclines(cu_die, &lines, &cnt, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+
+        for (i = 0; i < cnt; i++) {
+                ret = dwarf_line_srcfileno(lines[i], &fno, &__dw_error);
+                ERR_IF(ret != DW_DLV_OK);
+                if (fno != pf->fno)
+                        continue;
+
+                ret = dwarf_lineno(lines[i], &lineno, &__dw_error);
+                ERR_IF(ret != DW_DLV_OK);
+                if (lineno != (Dwarf_Unsigned)pp->line)
+                        continue;
+
+                ret = dwarf_lineaddr(lines[i], &addr, &__dw_error);
+                ERR_IF(ret != DW_DLV_OK);
+                debug("Probe point found: 0x%llx\n", addr);
+                pf->addr = addr;
+                /* Search a real subprogram including this line, */
+                ret = search_die_from_children(cu_die, probeaddr_callback, pf);
+                if (ret == 0)
+                        msg_exit(-1,
+                                 "Probe point is not found in subprograms.\n");
+                /* Continuing, because target line might be inlined. */
+        }
+        dwarf_srclines_dealloc(__dw_debug, lines, cnt);
+}
+
+/* Search function from function name */
+static int probefunc_callback(struct die_link *dlink, void *data)
+{
+        struct probe_finder *pf = (struct probe_finder *)data;
+        struct probe_point *pp = pf->pp;
+        struct die_link *lk;
+        Dwarf_Signed offs;
+        Dwarf_Half tag;
+        int ret;
+
+        ret = dwarf_tag(dlink->die, &tag, &__dw_error);
+        ERR_IF(ret == DW_DLV_ERROR);
+        if (tag == DW_TAG_subprogram) {
+                if (die_compare_name(dlink->die, pp->function) == 0) {
+                        if (die_inlined_subprogram(dlink->die)) {
+                                /* Inlined function, save it. */
+                                ret = dwarf_die_CU_offset(dlink->die,
+                                                          &pf->inl_offs,
+                                                          &__dw_error);
+                                ERR_IF(ret != DW_DLV_OK);
+                                debug("inline definition offset %lld\n",
+                                        pf->inl_offs);
+                                return 0;
+                        }
+                        /* Get probe address */
+                        pf->addr = die_get_entrypc(dlink->die);
+                        pf->addr += pp->offset;
+                        /* TODO: Check the address in this function */
+                        show_probepoint(dlink->die, pp->offset, pf);
+                        /* Continue to search */
+                }
+        } else if (tag == DW_TAG_inlined_subroutine && pf->inl_offs) {
+                if (die_get_abstract_origin(dlink->die) == pf->inl_offs) {
+                        /* Get probe address */
+                        pf->addr = die_get_entrypc(dlink->die);
+                        pf->addr += pp->offset;
+                        debug("found inline addr: 0x%llx\n", pf->addr);
+                        /* Inlined function. Get a real subprogram */
+                        for (lk = dlink->parent; lk != NULL; lk = lk->parent) {
+                                tag = 0;
+                                dwarf_tag(lk->die, &tag, &__dw_error);
+                                ERR_IF(ret == DW_DLV_ERROR);
+                                if (tag == DW_TAG_subprogram &&
+                                    !die_inlined_subprogram(lk->die))
+                                        goto found;
+                        }
+                        msg_exit(-1, "Failed to find real subprogram.\n");
+found:
+                        /* Get offset from subprogram */
+                        ret = die_within_subprogram(lk->die, pf->addr, &offs);
+                        ERR_IF(!ret);
+                        show_probepoint(lk->die, offs, pf);
+                        /* Continue to search */
+                }
+        }
+        return 0;
+}
+
+static void find_by_func(Dwarf_Die cu_die, struct probe_finder *pf)
+{
+        search_die_from_children(cu_die, probefunc_callback, pf);
+}
+
+/* Find a probe point */
+int find_probepoint(int fd, struct probe_point *pp)
+{
+        Dwarf_Half addr_size = 0;
+        Dwarf_Unsigned next_cuh = 0;
+        Dwarf_Die cu_die = 0;
+        int cu_number = 0, ret;
+        struct probe_finder pf = {.pp = pp};
+
+        ret = dwarf_init(fd, DW_DLC_READ, 0, 0, &__dw_debug, &__dw_error);
+        if (ret != DW_DLV_OK)
+                msg_exit(-1, "Failed to call dwarf_init(). "
+                         "Maybe, not a dwarf file?\n");
+
+        pp->found = 0;
+        while (++cu_number) {
+                /* Search CU (Compilation Unit) */
+                ret = dwarf_next_cu_header(__dw_debug, NULL, NULL, NULL,
+                        &addr_size, &next_cuh, &__dw_error);
+                ERR_IF(ret == DW_DLV_ERROR);
+                if (ret == DW_DLV_NO_ENTRY)
+                        break;
+
+                /* Get the DIE(Debugging Information Entry) of this CU */
+                ret = dwarf_siblingof(__dw_debug, 0, &cu_die, &__dw_error);
+                ERR_IF(ret != DW_DLV_OK);
+
+                /* Check if target file is included. */
+                if (pp->file)
+                        pf.fno = die_get_fileno(cu_die, pp->file);
+
+                if (!pp->file || pf.fno) {
+                        /* Save CU base address (for frame_base) */
+                        ret = dwarf_lowpc(cu_die, &pf.cu_base, &__dw_error);
+                        ERR_IF(ret == DW_DLV_ERROR);
+                        if (ret == DW_DLV_NO_ENTRY)
+                                pf.cu_base = 0;
+                        if (pp->line)
+                                find_by_line(cu_die, &pf);
+                        if (pp->function)
+                                find_by_func(cu_die, &pf);
+                }
+                dwarf_dealloc(__dw_debug, cu_die, DW_DLA_DIE);
+        }
+        ret = dwarf_finish(__dw_debug, &__dw_error);
+        ERR_IF(ret != DW_DLV_OK);
+
+        return pp->found;
+}
+