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    Subject[PATCH -tip v2 7/8] perf probe: Remove die() from probe-finder code
    Date
    Remove die() and DIE_IF() code from util/probe-finder.c since
    these 'sudden death' in utility functions make reusing it from
    other code (especially tui/gui) difficult.

    Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Paul Mackerras <paulus@samba.org>
    Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Mike Galbraith <efault@gmx.de>
    Cc: Frederic Weisbecker <fweisbec@gmail.com>
    ---

    tools/perf/util/probe-event.c | 4
    tools/perf/util/probe-finder.c | 517 +++++++++++++++++++++++++---------------
    2 files changed, 322 insertions(+), 199 deletions(-)

    diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
    index bef2805..7893b32 100644
    --- a/tools/perf/util/probe-event.c
    +++ b/tools/perf/util/probe-event.c
    @@ -151,10 +151,10 @@ static int try_to_find_kprobe_trace_events(struct perf_probe_event *pev,

    /* Error path */
    if (need_dwarf) {
    - if (ntevs == -ENOENT)
    + if (ntevs == -EBADF)
    pr_warning("No dwarf info found in the vmlinux - "
    "please rebuild with CONFIG_DEBUG_INFO=y.\n");
    - die("Could not analyze debuginfo.");
    + die("Failed to analyze debuginfo.");
    }
    pr_debug("An error occurred in debuginfo analysis."
    " Try to use symbols.\n");
    diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
    index 1f45285..4a57504 100644
    --- a/tools/perf/util/probe-finder.c
    +++ b/tools/perf/util/probe-finder.c
    @@ -196,19 +196,7 @@ static bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
    {
    const char *name;
    name = dwarf_diename(dw_die);
    - DIE_IF(name == NULL);
    - return strcmp(tname, name);
    -}
    -
    -/* Get entry pc(or low pc, 1st entry of ranges) of the die */
    -static Dwarf_Addr die_get_entrypc(Dwarf_Die *dw_die)
    -{
    - Dwarf_Addr epc;
    - int ret;
    -
    - ret = dwarf_entrypc(dw_die, &epc);
    - DIE_IF(ret == -1);
    - return epc;
    + return name ? strcmp(tname, name) : -1;
    }

    /* Get type die, but skip qualifiers and typedef */
    @@ -390,7 +378,7 @@ static Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
    */

    /* Show a location */
    -static void convert_location(Dwarf_Op *op, struct probe_finder *pf)
    +static int convert_location(Dwarf_Op *op, struct probe_finder *pf)
    {
    unsigned int regn;
    Dwarf_Word offs = 0;
    @@ -400,8 +388,11 @@ static void convert_location(Dwarf_Op *op, struct probe_finder *pf)

    /* If this is based on frame buffer, set the offset */
    if (op->atom == DW_OP_fbreg) {
    - if (pf->fb_ops == NULL)
    - die("The attribute of frame base is not supported.\n");
    + if (pf->fb_ops == NULL) {
    + pr_warning("The attribute of frame base is not "
    + "supported.\n");
    + return -ENOTSUP;
    + }
    ref = true;
    offs = op->number;
    op = &pf->fb_ops[0];
    @@ -419,50 +410,63 @@ static void convert_location(Dwarf_Op *op, struct probe_finder *pf)
    ref = true;
    } else if (op->atom == DW_OP_regx) {
    regn = op->number;
    - } else
    - die("DW_OP %d is not supported.", op->atom);
    + } else {
    + pr_warning("DW_OP %d is not supported.\n", op->atom);
    + return -ENOTSUP;
    + }

    regs = get_arch_regstr(regn);
    - if (!regs)
    - die("%u exceeds max register number.", regn);
    + if (!regs) {
    + pr_warning("%u exceeds max register number.\n", regn);
    + return -ERANGE;
    + }

    tvar->value = xstrdup(regs);
    if (ref) {
    tvar->ref = xzalloc(sizeof(struct kprobe_trace_arg_ref));
    tvar->ref->offset = (long)offs;
    }
    + return 0;
    }

    -static void convert_variable_type(Dwarf_Die *vr_die,
    - struct kprobe_trace_arg *targ)
    +static int convert_variable_type(Dwarf_Die *vr_die,
    + struct kprobe_trace_arg *targ)
    {
    Dwarf_Die type;
    char buf[16];
    int ret;

    - if (die_get_real_type(vr_die, &type) == NULL)
    - die("Failed to get a type information of %s.",
    - dwarf_diename(vr_die));
    + if (die_get_real_type(vr_die, &type) == NULL) {
    + pr_warning("Failed to get a type information of %s.\n",
    + dwarf_diename(vr_die));
    + return -ENOENT;
    + }

    ret = die_get_byte_size(&type) * 8;
    if (ret) {
    /* Check the bitwidth */
    if (ret > MAX_BASIC_TYPE_BITS) {
    - pr_warning(" Warning: %s exceeds max-bitwidth."
    - " Cut down to %d bits.\n",
    - dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
    + pr_info("%s exceeds max-bitwidth."
    + " Cut down to %d bits.\n",
    + dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
    ret = MAX_BASIC_TYPE_BITS;
    }

    ret = snprintf(buf, 16, "%c%d",
    die_is_signed_type(&type) ? 's' : 'u', ret);
    - if (ret < 0 || ret >= 16)
    - die("Failed to convert variable type.");
    + if (ret < 0 || ret >= 16) {
    + if (ret >= 16)
    + ret = -E2BIG;
    + pr_warning("Failed to convert variable type: %s\n",
    + strerror(-ret));
    + return ret;
    + }
    targ->type = xstrdup(buf);
    }
    + return 0;
    }

    -static void convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
    +static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
    struct perf_probe_arg_field *field,
    struct kprobe_trace_arg_ref **ref_ptr,
    Dwarf_Die *die_mem)
    @@ -473,21 +477,28 @@ static void convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
    Dwarf_Word offs;

    pr_debug("converting %s in %s\n", field->name, varname);
    - if (die_get_real_type(vr_die, &type) == NULL)
    - die("Failed to get a type information of %s.", varname);
    + if (die_get_real_type(vr_die, &type) == NULL) {
    + pr_warning("Failed to get the type of %s.\n", varname);
    + return -ENOENT;
    + }

    /* Check the pointer and dereference */
    if (dwarf_tag(&type) == DW_TAG_pointer_type) {
    - if (!field->ref)
    - die("Semantic error: %s must be referred by '->'",
    - field->name);
    + if (!field->ref) {
    + pr_err("Semantic error: %s must be referred by '->'\n",
    + field->name);
    + return -EINVAL;
    + }
    /* Get the type pointed by this pointer */
    - if (die_get_real_type(&type, &type) == NULL)
    - die("Failed to get a type information of %s.", varname);
    -
    + if (die_get_real_type(&type, &type) == NULL) {
    + pr_warning("Failed to get the type of %s.\n", varname);
    + return -ENOENT;
    + }
    /* Verify it is a data structure */
    - if (dwarf_tag(&type) != DW_TAG_structure_type)
    - die("%s is not a data structure.", varname);
    + if (dwarf_tag(&type) != DW_TAG_structure_type) {
    + pr_warning("%s is not a data structure.\n", varname);
    + return -EINVAL;
    + }

    ref = xzalloc(sizeof(struct kprobe_trace_arg_ref));
    if (*ref_ptr)
    @@ -496,34 +507,46 @@ static void convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
    *ref_ptr = ref;
    } else {
    /* Verify it is a data structure */
    - if (dwarf_tag(&type) != DW_TAG_structure_type)
    - die("%s is not a data structure.", varname);
    -
    - if (field->ref)
    - die("Semantic error: %s must be referred by '.'",
    - field->name);
    - if (!ref)
    - die("Structure on a register is not supported yet.");
    + if (dwarf_tag(&type) != DW_TAG_structure_type) {
    + pr_warning("%s is not a data structure.\n", varname);
    + return -EINVAL;
    + }
    + if (field->ref) {
    + pr_err("Semantic error: %s must be referred by '.'\n",
    + field->name);
    + return -EINVAL;
    + }
    + if (!ref) {
    + pr_warning("Structure on a register is not "
    + "supported yet.\n");
    + return -ENOTSUP;
    + }
    }

    - if (die_find_member(&type, field->name, die_mem) == NULL)
    - die("%s(tyep:%s) has no member %s.", varname,
    - dwarf_diename(&type), field->name);
    + if (die_find_member(&type, field->name, die_mem) == NULL) {
    + pr_warning("%s(tyep:%s) has no member %s.\n", varname,
    + dwarf_diename(&type), field->name);
    + return -EINVAL;
    + }

    /* Get the offset of the field */
    if (dwarf_attr(die_mem, DW_AT_data_member_location, &attr) == NULL ||
    - dwarf_formudata(&attr, &offs) != 0)
    - die("Failed to get the offset of %s.", field->name);
    + dwarf_formudata(&attr, &offs) != 0) {
    + pr_warning("Failed to get the offset of %s.\n", field->name);
    + return -ENOENT;
    + }
    ref->offset += (long)offs;

    /* Converting next field */
    if (field->next)
    - convert_variable_fields(die_mem, field->name, field->next,
    - &ref, die_mem);
    + return convert_variable_fields(die_mem, field->name,
    + field->next, &ref, die_mem);
    + else
    + return 0;
    }

    /* Show a variables in kprobe event format */
    -static void convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
    +static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
    {
    Dwarf_Attribute attr;
    Dwarf_Die die_mem;
    @@ -538,28 +561,30 @@ static void convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
    if (ret <= 0 || nexpr == 0)
    goto error;

    - convert_location(expr, pf);
    -
    - if (pf->pvar->field) {
    - convert_variable_fields(vr_die, pf->pvar->var,
    - pf->pvar->field, &pf->tvar->ref,
    - &die_mem);
    + ret = convert_location(expr, pf);
    + if (ret == 0 && pf->pvar->field) {
    + ret = convert_variable_fields(vr_die, pf->pvar->var,
    + pf->pvar->field, &pf->tvar->ref,
    + &die_mem);
    vr_die = &die_mem;
    }
    - if (pf->pvar->type)
    - pf->tvar->type = xstrdup(pf->pvar->type);
    - else
    - convert_variable_type(vr_die, pf->tvar);
    + if (ret == 0) {
    + if (pf->pvar->type)
    + pf->tvar->type = xstrdup(pf->pvar->type);
    + else
    + ret = convert_variable_type(vr_die, pf->tvar);
    + }
    /* *expr will be cached in libdw. Don't free it. */
    - return ;
    + return ret;
    error:
    /* TODO: Support const_value */
    - die("Failed to find the location of %s at this address.\n"
    - " Perhaps, it has been optimized out.", pf->pvar->var);
    + pr_err("Failed to find the location of %s at this address.\n"
    + " Perhaps, it has been optimized out.\n", pf->pvar->var);
    + return -ENOENT;
    }

    /* Find a variable in a subprogram die */
    -static void find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
    +static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
    {
    Dwarf_Die vr_die;
    char buf[32], *ptr;
    @@ -578,19 +603,22 @@ static void find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
    if (!is_c_varname(pf->pvar->var)) {
    /* Copy raw parameters */
    pf->tvar->value = xstrdup(pf->pvar->var);
    - } else {
    - pr_debug("Searching '%s' variable in context.\n",
    - pf->pvar->var);
    - /* Search child die for local variables and parameters. */
    - if (!die_find_variable(sp_die, pf->pvar->var, &vr_die))
    - die("Failed to find '%s' in this function.",
    - pf->pvar->var);
    - convert_variable(&vr_die, pf);
    + return 0;
    }
    +
    + pr_debug("Searching '%s' variable in context.\n",
    + pf->pvar->var);
    + /* Search child die for local variables and parameters. */
    + if (!die_find_variable(sp_die, pf->pvar->var, &vr_die)) {
    + pr_warning("Failed to find '%s' in this function.\n",
    + pf->pvar->var);
    + return -ENOENT;
    + }
    + return convert_variable(&vr_die, pf);
    }

    /* Show a probe point to output buffer */
    -static void convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
    +static int convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
    {
    struct kprobe_trace_event *tev;
    Dwarf_Addr eaddr;
    @@ -600,22 +628,31 @@ static void convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
    Dwarf_Attribute fb_attr;
    size_t nops;

    - if (pf->ntevs == MAX_PROBES)
    - die("Too many( > %d) probe point found.\n", MAX_PROBES);
    + if (pf->ntevs == MAX_PROBES) {
    + pr_warning("Too many( > %d) probe point found.\n", MAX_PROBES);
    + return -ERANGE;
    + }
    tev = &pf->tevs[pf->ntevs++];

    /* If no real subprogram, find a real one */
    if (!sp_die || dwarf_tag(sp_die) != DW_TAG_subprogram) {
    sp_die = die_find_real_subprogram(&pf->cu_die,
    pf->addr, &die_mem);
    - if (!sp_die)
    - die("Probe point is not found in subprograms.");
    + if (!sp_die) {
    + pr_warning("Failed to find probe point in any "
    + "functions.\n");
    + return -ENOENT;
    + }
    }

    /* Copy the name of probe point */
    name = dwarf_diename(sp_die);
    if (name) {
    - dwarf_entrypc(sp_die, &eaddr);
    + if (dwarf_entrypc(sp_die, &eaddr) != 0) {
    + pr_warning("Failed to get entry pc of %s\n",
    + dwarf_diename(sp_die));
    + return -ENOENT;
    + }
    tev->point.symbol = xstrdup(name);
    tev->point.offset = (unsigned long)(pf->addr - eaddr);
    } else
    @@ -633,9 +670,12 @@ static void convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
    } else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
    pf->cfi != NULL) {
    Dwarf_Frame *frame;
    - ret = dwarf_cfi_addrframe(pf->cfi, pf->addr, &frame);
    - DIE_IF(ret != 0);
    - dwarf_frame_cfa(frame, &pf->fb_ops, &nops);
    + if (dwarf_cfi_addrframe(pf->cfi, pf->addr, &frame) != 0 ||
    + dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
    + pr_warning("Failed to get CFA on 0x%jx\n",
    + (uintmax_t)pf->addr);
    + return -ENOENT;
    + }
    }

    /* Find each argument */
    @@ -644,45 +684,53 @@ static void convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
    for (i = 0; i < pf->pev->nargs; i++) {
    pf->pvar = &pf->pev->args[i];
    pf->tvar = &tev->args[i];
    - find_variable(sp_die, pf);
    + ret = find_variable(sp_die, pf);
    + if (ret != 0)
    + return ret;
    }

    /* *pf->fb_ops will be cached in libdw. Don't free it. */
    pf->fb_ops = NULL;
    + return 0;
    }

    /* Find probe point from its line number */
    -static void find_probe_point_by_line(struct probe_finder *pf)
    +static int find_probe_point_by_line(struct probe_finder *pf)
    {
    Dwarf_Lines *lines;
    Dwarf_Line *line;
    size_t nlines, i;
    Dwarf_Addr addr;
    int lineno;
    - int ret;
    + int ret = 0;

    - ret = dwarf_getsrclines(&pf->cu_die, &lines, &nlines);
    - DIE_IF(ret != 0);
    + if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) {
    + pr_warning("No source lines found in this CU.\n");
    + return -ENOENT;
    + }

    - for (i = 0; i < nlines; i++) {
    + for (i = 0; i < nlines && ret == 0; i++) {
    line = dwarf_onesrcline(lines, i);
    - dwarf_lineno(line, &lineno);
    - if (lineno != pf->lno)
    + if (dwarf_lineno(line, &lineno) != 0 ||
    + lineno != pf->lno)
    continue;

    /* TODO: Get fileno from line, but how? */
    if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0)
    continue;

    - ret = dwarf_lineaddr(line, &addr);
    - DIE_IF(ret != 0);
    + if (dwarf_lineaddr(line, &addr) != 0) {
    + pr_warning("Failed to get the address of the line.\n");
    + return -ENOENT;
    + }
    pr_debug("Probe line found: line[%d]:%d addr:0x%jx\n",
    (int)i, lineno, (uintmax_t)addr);
    pf->addr = addr;

    - convert_probe_point(NULL, pf);
    + ret = convert_probe_point(NULL, pf);
    /* Continuing, because target line might be inlined. */
    }
    + return ret;
    }

    /* Find lines which match lazy pattern */
    @@ -690,15 +738,27 @@ static int find_lazy_match_lines(struct list_head *head,
    const char *fname, const char *pat)
    {
    char *fbuf, *p1, *p2;
    - int fd, line, nlines = 0;
    + int fd, ret, line, nlines = 0;
    struct stat st;

    fd = open(fname, O_RDONLY);
    - if (fd < 0)
    - die("failed to open %s", fname);
    - DIE_IF(fstat(fd, &st) < 0);
    + if (fd < 0) {
    + pr_warning("Failed to open %s: %s\n", fname, strerror(-fd));
    + return fd;
    + }
    +
    + ret = fstat(fd, &st);
    + if (ret < 0) {
    + pr_warning("Failed to get the size of %s: %s\n",
    + fname, strerror(errno));
    + return ret;
    + }
    fbuf = xmalloc(st.st_size + 2);
    - DIE_IF(read(fd, fbuf, st.st_size) < 0);
    + ret = read(fd, fbuf, st.st_size);
    + if (ret < 0) {
    + pr_warning("Failed to read %s: %s\n", fname, strerror(errno));
    + return ret;
    + }
    close(fd);
    fbuf[st.st_size] = '\n'; /* Dummy line */
    fbuf[st.st_size + 1] = '\0';
    @@ -718,7 +778,7 @@ static int find_lazy_match_lines(struct list_head *head,
    }

    /* Find probe points from lazy pattern */
    -static void find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
    +static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
    {
    Dwarf_Lines *lines;
    Dwarf_Line *line;
    @@ -726,31 +786,40 @@ static void find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
    Dwarf_Addr addr;
    Dwarf_Die die_mem;
    int lineno;
    - int ret;
    + int ret = 0;

    if (list_empty(&pf->lcache)) {
    /* Matching lazy line pattern */
    ret = find_lazy_match_lines(&pf->lcache, pf->fname,
    pf->pev->point.lazy_line);
    - if (ret <= 0)
    - die("No matched lines found in %s.", pf->fname);
    + if (ret == 0) {
    + pr_debug("No matched lines found in %s.\n", pf->fname);
    + return 0;
    + } else if (ret < 0)
    + return ret;
    }

    - ret = dwarf_getsrclines(&pf->cu_die, &lines, &nlines);
    - DIE_IF(ret != 0);
    - for (i = 0; i < nlines; i++) {
    + if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) {
    + pr_warning("No source lines found in this CU.\n");
    + return -ENOENT;
    + }
    +
    + for (i = 0; i < nlines && ret >= 0; i++) {
    line = dwarf_onesrcline(lines, i);

    - dwarf_lineno(line, &lineno);
    - if (!line_list__has_line(&pf->lcache, lineno))
    + if (dwarf_lineno(line, &lineno) != 0 ||
    + !line_list__has_line(&pf->lcache, lineno))
    continue;

    /* TODO: Get fileno from line, but how? */
    if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0)
    continue;

    - ret = dwarf_lineaddr(line, &addr);
    - DIE_IF(ret != 0);
    + if (dwarf_lineaddr(line, &addr) != 0) {
    + pr_debug("Failed to get the address of line %d.\n",
    + lineno);
    + continue;
    + }
    if (sp_die) {
    /* Address filtering 1: does sp_die include addr? */
    if (!dwarf_haspc(sp_die, addr))
    @@ -764,27 +833,42 @@ static void find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
    (int)i, lineno, (unsigned long long)addr);
    pf->addr = addr;

    - convert_probe_point(sp_die, pf);
    + ret = convert_probe_point(sp_die, pf);
    /* Continuing, because target line might be inlined. */
    }
    /* TODO: deallocate lines, but how? */
    + return ret;
    }

    +/* Callback parameter with return value */
    +struct dwarf_callback_param {
    + void *data;
    + int retval;
    +};
    +
    static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
    {
    - struct probe_finder *pf = (struct probe_finder *)data;
    + struct dwarf_callback_param *param = data;
    + struct probe_finder *pf = param->data;
    struct perf_probe_point *pp = &pf->pev->point;
    + Dwarf_Addr addr;

    if (pp->lazy_line)
    - find_probe_point_lazy(in_die, pf);
    + param->retval = find_probe_point_lazy(in_die, pf);
    else {
    /* Get probe address */
    - pf->addr = die_get_entrypc(in_die);
    + if (dwarf_entrypc(in_die, &addr) != 0) {
    + pr_warning("Failed to get entry pc of %s.\n",
    + dwarf_diename(in_die));
    + param->retval = -ENOENT;
    + return DWARF_CB_ABORT;
    + }
    + pf->addr = addr;
    pf->addr += pp->offset;
    pr_debug("found inline addr: 0x%jx\n",
    (uintmax_t)pf->addr);

    - convert_probe_point(in_die, pf);
    + param->retval = convert_probe_point(in_die, pf);
    }

    return DWARF_CB_OK;
    @@ -793,39 +877,53 @@ static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
    /* Search function from function name */
    static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
    {
    - struct probe_finder *pf = (struct probe_finder *)data;
    + struct dwarf_callback_param *param = data;
    + struct probe_finder *pf = param->data;
    struct perf_probe_point *pp = &pf->pev->point;

    /* Check tag and diename */
    if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
    die_compare_name(sp_die, pp->function) != 0)
    - return 0;
    + return DWARF_CB_OK;

    pf->fname = dwarf_decl_file(sp_die);
    if (pp->line) { /* Function relative line */
    dwarf_decl_line(sp_die, &pf->lno);
    pf->lno += pp->line;
    - find_probe_point_by_line(pf);
    + param->retval = find_probe_point_by_line(pf);
    } else if (!dwarf_func_inline(sp_die)) {
    /* Real function */
    if (pp->lazy_line)
    - find_probe_point_lazy(sp_die, pf);
    + param->retval = find_probe_point_lazy(sp_die, pf);
    else {
    - pf->addr = die_get_entrypc(sp_die);
    + if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
    + pr_warning("Failed to get entry pc of %s.\n",
    + dwarf_diename(sp_die));
    + param->retval = -ENOENT;
    + return DWARF_CB_ABORT;
    + }
    pf->addr += pp->offset;
    /* TODO: Check the address in this function */
    - convert_probe_point(sp_die, pf);
    + param->retval = convert_probe_point(sp_die, pf);
    }
    - } else
    + } else {
    + struct dwarf_callback_param _param = {.data = (void *)pf,
    + .retval = 0};
    /* Inlined function: search instances */
    - dwarf_func_inline_instances(sp_die, probe_point_inline_cb, pf);
    + dwarf_func_inline_instances(sp_die, probe_point_inline_cb,
    + &_param);
    + param->retval = _param.retval;
    + }

    - return 1; /* Exit; no same symbol in this CU. */
    + return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
    }

    -static void find_probe_point_by_func(struct probe_finder *pf)
    +static int find_probe_point_by_func(struct probe_finder *pf)
    {
    - dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, pf, 0);
    + struct dwarf_callback_param _param = {.data = (void *)pf,
    + .retval = 0};
    + dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
    + return _param.retval;
    }

    /* Find kprobe_trace_events specified by perf_probe_event from debuginfo */
    @@ -838,14 +936,18 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
    size_t cuhl;
    Dwarf_Die *diep;
    Dwarf *dbg;
    + int ret = 0;

    pf.tevs = xzalloc(sizeof(struct kprobe_trace_event) * MAX_PROBES);
    *tevs = pf.tevs;
    pf.ntevs = 0;

    dbg = dwarf_begin(fd, DWARF_C_READ);
    - if (!dbg)
    - return -ENOENT;
    + if (!dbg) {
    + pr_warning("No dwarf info found in the vmlinux - "
    + "please rebuild with CONFIG_DEBUG_INFO=y.\n");
    + return -EBADF;
    + }

    /* Get the call frame information from this dwarf */
    pf.cfi = dwarf_getcfi(dbg);
    @@ -853,7 +955,8 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
    off = 0;
    line_list__init(&pf.lcache);
    /* Loop on CUs (Compilation Unit) */
    - while (!dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
    + while (!dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) &&
    + ret >= 0) {
    /* Get the DIE(Debugging Information Entry) of this CU */
    diep = dwarf_offdie(dbg, off + cuhl, &pf.cu_die);
    if (!diep)
    @@ -867,12 +970,12 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,

    if (!pp->file || pf.fname) {
    if (pp->function)
    - find_probe_point_by_func(&pf);
    + ret = find_probe_point_by_func(&pf);
    else if (pp->lazy_line)
    - find_probe_point_lazy(NULL, &pf);
    + ret = find_probe_point_lazy(NULL, &pf);
    else {
    pf.lno = pp->line;
    - find_probe_point_by_line(&pf);
    + ret = find_probe_point_by_line(&pf);
    }
    }
    off = noff;
    @@ -880,7 +983,7 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
    line_list__free(&pf.lcache);
    dwarf_end(dbg);

    - return pf.ntevs;
    + return (ret < 0) ? ret : pf.ntevs;
    }

    /* Reverse search */
    @@ -893,10 +996,11 @@ int find_perf_probe_point(int fd, unsigned long addr,
    Dwarf_Addr laddr, eaddr;
    const char *tmp;
    int lineno, ret = 0;
    + bool found = false;

    dbg = dwarf_begin(fd, DWARF_C_READ);
    if (!dbg)
    - return -ENOENT;
    + return -EBADF;

    /* Find cu die */
    if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie)) {
    @@ -907,82 +1011,87 @@ int find_perf_probe_point(int fd, unsigned long addr,
    /* Find a corresponding line */
    line = dwarf_getsrc_die(&cudie, (Dwarf_Addr)addr);
    if (line) {
    - dwarf_lineaddr(line, &laddr);
    - if ((Dwarf_Addr)addr == laddr) {
    - dwarf_lineno(line, &lineno);
    - ppt->line = lineno;
    -
    + if (dwarf_lineaddr(line, &laddr) == 0 &&
    + (Dwarf_Addr)addr == laddr &&
    + dwarf_lineno(line, &lineno) == 0) {
    tmp = dwarf_linesrc(line, NULL, NULL);
    - DIE_IF(!tmp);
    - ppt->file = xstrdup(tmp);
    - ret = 1;
    + if (tmp) {
    + ppt->line = lineno;
    + ppt->file = xstrdup(tmp);
    + found = true;
    + }
    }
    }

    /* Find a corresponding function */
    if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) {
    tmp = dwarf_diename(&spdie);
    - if (!tmp)
    + if (!tmp || dwarf_entrypc(&spdie, &eaddr) != 0)
    goto end;

    - dwarf_entrypc(&spdie, &eaddr);
    - if (!lineno) {
    - /* We don't have a line number, let's use offset */
    - ppt->function = xstrdup(tmp);
    - ppt->offset = addr - (unsigned long)eaddr;
    - ret = 1;
    - goto end;
    - }
    - if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr, &indie)) {
    - /* addr in an inline function */
    - tmp = dwarf_diename(&indie);
    - if (!tmp)
    - goto end;
    - dwarf_decl_line(&indie, &lineno);
    - } else {
    - if (eaddr == addr) /* No offset: function entry */
    - lineno = ppt->line;
    - else
    - dwarf_decl_line(&spdie, &lineno);
    + if (ppt->line) {
    + if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
    + &indie)) {
    + /* addr in an inline function */
    + tmp = dwarf_diename(&indie);
    + if (!tmp)
    + goto end;
    + ret = dwarf_decl_line(&indie, &lineno);
    + } else {
    + if (eaddr == addr) { /* Function entry */
    + lineno = ppt->line;
    + ret = 0;
    + } else
    + ret = dwarf_decl_line(&spdie, &lineno);
    + }
    + if (ret == 0) {
    + /* Make a relative line number */
    + ppt->line -= lineno;
    + goto found;
    + }
    }
    + /* We don't have a line number, let's use offset */
    + ppt->offset = addr - (unsigned long)eaddr;
    +found:
    ppt->function = xstrdup(tmp);
    - ppt->line -= lineno; /* Make a relative line number */
    + found = true;
    }

    end:
    dwarf_end(dbg);
    + if (ret >= 0)
    + ret = found ? 1 : 0;
    return ret;
    }


    /* Find line range from its line number */
    -static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
    +static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
    {
    Dwarf_Lines *lines;
    Dwarf_Line *line;
    size_t nlines, i;
    Dwarf_Addr addr;
    int lineno;
    - int ret;
    const char *src;
    Dwarf_Die die_mem;

    line_list__init(&lf->lr->line_list);
    - ret = dwarf_getsrclines(&lf->cu_die, &lines, &nlines);
    - DIE_IF(ret != 0);
    + if (dwarf_getsrclines(&lf->cu_die, &lines, &nlines) != 0) {
    + pr_warning("No source lines found in this CU.\n");
    + return -ENOENT;
    + }

    for (i = 0; i < nlines; i++) {
    line = dwarf_onesrcline(lines, i);
    - ret = dwarf_lineno(line, &lineno);
    - DIE_IF(ret != 0);
    - if (lf->lno_s > lineno || lf->lno_e < lineno)
    + if (dwarf_lineno(line, &lineno) != 0 ||
    + (lf->lno_s > lineno || lf->lno_e < lineno))
    continue;

    if (sp_die) {
    /* Address filtering 1: does sp_die include addr? */
    - ret = dwarf_lineaddr(line, &addr);
    - DIE_IF(ret != 0);
    - if (!dwarf_haspc(sp_die, addr))
    + if (dwarf_lineaddr(line, &addr) != 0 ||
    + !dwarf_haspc(sp_die, addr))
    continue;

    /* Address filtering 2: No child include addr? */
    @@ -1007,18 +1116,22 @@ static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
    free(lf->lr->path);
    lf->lr->path = NULL;
    }
    + return lf->found;
    }

    static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
    {
    - find_line_range_by_line(in_die, (struct line_finder *)data);
    + struct dwarf_callback_param *param = data;
    +
    + param->retval = find_line_range_by_line(in_die, param->data);
    return DWARF_CB_ABORT; /* No need to find other instances */
    }

    /* Search function from function name */
    static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
    {
    - struct line_finder *lf = (struct line_finder *)data;
    + struct dwarf_callback_param *param = data;
    + struct line_finder *lf = param->data;
    struct line_range *lr = lf->lr;

    if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
    @@ -1033,38 +1146,47 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
    lf->lno_e = lr->offset + lr->end;
    lr->start = lf->lno_s;
    lr->end = lf->lno_e;
    - if (dwarf_func_inline(sp_die))
    + if (dwarf_func_inline(sp_die)) {
    + struct dwarf_callback_param _param;
    + _param.data = (void *)lf;
    + _param.retval = 0;
    dwarf_func_inline_instances(sp_die,
    - line_range_inline_cb, lf);
    - else
    - find_line_range_by_line(sp_die, lf);
    - return 1;
    + line_range_inline_cb,
    + &_param);
    + param->retval = _param.retval;
    + } else
    + param->retval = find_line_range_by_line(sp_die, lf);
    + return DWARF_CB_ABORT;
    }
    - return 0;
    + return DWARF_CB_OK;
    }

    -static void find_line_range_by_func(struct line_finder *lf)
    +static int find_line_range_by_func(struct line_finder *lf)
    {
    - dwarf_getfuncs(&lf->cu_die, line_range_search_cb, lf, 0);
    + struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
    + dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
    + return param.retval;
    }

    int find_line_range(int fd, struct line_range *lr)
    {
    struct line_finder lf = {.lr = lr, .found = 0};
    - int ret;
    + int ret = 0;
    Dwarf_Off off = 0, noff;
    size_t cuhl;
    Dwarf_Die *diep;
    Dwarf *dbg;

    dbg = dwarf_begin(fd, DWARF_C_READ);
    - if (!dbg)
    - return -ENOENT;
    + if (!dbg) {
    + pr_warning("No dwarf info found in the vmlinux - "
    + "please rebuild with CONFIG_DEBUG_INFO=y.\n");
    + return -EBADF;
    + }

    /* Loop on CUs (Compilation Unit) */
    - while (!lf.found) {
    - ret = dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL);
    - if (ret != 0)
    + while (!lf.found && ret >= 0) {
    + if (dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 0)
    break;

    /* Get the DIE(Debugging Information Entry) of this CU */
    @@ -1080,20 +1202,21 @@ int find_line_range(int fd, struct line_range *lr)

    if (!lr->file || lf.fname) {
    if (lr->function)
    - find_line_range_by_func(&lf);
    + ret = find_line_range_by_func(&lf);
    else {
    lf.lno_s = lr->start;
    if (!lr->end)
    lf.lno_e = INT_MAX;
    else
    lf.lno_e = lr->end;
    - find_line_range_by_line(NULL, &lf);
    + ret = find_line_range_by_line(NULL, &lf);
    }
    }
    off = noff;
    }
    pr_debug("path: %lx\n", (unsigned long)lr->path);
    dwarf_end(dbg);
    - return lf.found;
    +
    + return (ret < 0) ? ret : lf.found;
    }


    --
    Masami Hiramatsu
    e-mail: mhiramat@redhat.com


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      Last update: 2010-04-07 00:03    [W:0.086 / U:32.032 seconds]
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