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Diffstat (limited to 'tools/perf/util/probe-finder.c')
-rw-r--r--tools/perf/util/probe-finder.c96
1 files changed, 75 insertions, 21 deletions
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 5c290c682afe..df4debe564da 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -39,6 +39,7 @@
#include "util.h"
#include "symbol.h"
#include "probe-finder.h"
+#include "probe-file.h"
/* Kprobe tracer basic type is up to u64 */
#define MAX_BASIC_TYPE_BITS 64
@@ -170,6 +171,7 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
*/
static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
Dwarf_Op *fb_ops, Dwarf_Die *sp_die,
+ unsigned int machine,
struct probe_trace_arg *tvar)
{
Dwarf_Attribute attr;
@@ -265,7 +267,7 @@ static_var:
if (!tvar)
return ret2;
- regs = get_arch_regstr(regn);
+ regs = get_dwarf_regstr(regn, machine);
if (!regs) {
/* This should be a bug in DWARF or this tool */
pr_warning("Mapping for the register number %u "
@@ -297,13 +299,13 @@ static int convert_variable_type(Dwarf_Die *vr_die,
char sbuf[STRERR_BUFSIZE];
int bsize, boffs, total;
int ret;
- char sign;
+ char prefix;
/* TODO: check all types */
- if (cast && strcmp(cast, "string") != 0 &&
+ if (cast && strcmp(cast, "string") != 0 && strcmp(cast, "x") != 0 &&
strcmp(cast, "s") != 0 && strcmp(cast, "u") != 0) {
/* Non string type is OK */
- /* and respect signedness cast */
+ /* and respect signedness/hexadecimal cast */
tvar->type = strdup(cast);
return (tvar->type == NULL) ? -ENOMEM : 0;
}
@@ -365,11 +367,15 @@ static int convert_variable_type(Dwarf_Die *vr_die,
}
if (cast && (strcmp(cast, "u") == 0))
- sign = 'u';
+ prefix = 'u';
else if (cast && (strcmp(cast, "s") == 0))
- sign = 's';
+ prefix = 's';
+ else if (cast && (strcmp(cast, "x") == 0) &&
+ probe_type_is_available(PROBE_TYPE_X))
+ prefix = 'x';
else
- sign = die_is_signed_type(&type) ? 's' : 'u';
+ prefix = die_is_signed_type(&type) ? 's' :
+ probe_type_is_available(PROBE_TYPE_X) ? 'x' : 'u';
ret = dwarf_bytesize(&type);
if (ret <= 0)
@@ -383,7 +389,7 @@ static int convert_variable_type(Dwarf_Die *vr_die,
dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
ret = MAX_BASIC_TYPE_BITS;
}
- ret = snprintf(buf, 16, "%c%d", sign, ret);
+ ret = snprintf(buf, 16, "%c%d", prefix, ret);
formatted:
if (ret < 0 || ret >= 16) {
@@ -538,7 +544,7 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
dwarf_diename(vr_die));
ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
- &pf->sp_die, pf->tvar);
+ &pf->sp_die, pf->machine, pf->tvar);
if (ret == -ENOENT || ret == -EINVAL) {
pr_err("Failed to find the location of the '%s' variable at this address.\n"
" Perhaps it has been optimized out.\n"
@@ -901,6 +907,38 @@ static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
}
+static void skip_prologue(Dwarf_Die *sp_die, struct probe_finder *pf)
+{
+ struct perf_probe_point *pp = &pf->pev->point;
+
+ /* Not uprobe? */
+ if (!pf->pev->uprobes)
+ return;
+
+ /* Compiled with optimization? */
+ if (die_is_optimized_target(&pf->cu_die))
+ return;
+
+ /* Don't know entrypc? */
+ if (!pf->addr)
+ return;
+
+ /* Only FUNC and FUNC@SRC are eligible. */
+ if (!pp->function || pp->line || pp->retprobe || pp->lazy_line ||
+ pp->offset || pp->abs_address)
+ return;
+
+ /* Not interested in func parameter? */
+ if (!perf_probe_with_var(pf->pev))
+ return;
+
+ pr_info("Target program is compiled without optimization. Skipping prologue.\n"
+ "Probe on address 0x%" PRIx64 " to force probing at the function entry.\n\n",
+ pf->addr);
+
+ die_skip_prologue(sp_die, &pf->cu_die, &pf->addr);
+}
+
static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
{
struct probe_finder *pf = data;
@@ -917,6 +955,11 @@ static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
dwarf_diename(in_die));
return -ENOENT;
}
+ if (addr == 0) {
+ pr_debug("%s has no valid entry address. skipped.\n",
+ dwarf_diename(in_die));
+ return -ENOENT;
+ }
pf->addr = addr;
pf->addr += pp->offset;
pr_debug("found inline addr: 0x%jx\n",
@@ -950,7 +993,8 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
if (pp->file && strtailcmp(pp->file, dwarf_decl_file(sp_die)))
return DWARF_CB_OK;
- pr_debug("Matched function: %s\n", dwarf_diename(sp_die));
+ pr_debug("Matched function: %s [%lx]\n", dwarf_diename(sp_die),
+ (unsigned long)dwarf_dieoffset(sp_die));
pf->fname = dwarf_decl_file(sp_die);
if (pp->line) { /* Function relative line */
dwarf_decl_line(sp_die, &pf->lno);
@@ -959,10 +1003,16 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
} else if (die_is_func_instance(sp_die)) {
/* Instances always have the entry address */
dwarf_entrypc(sp_die, &pf->addr);
+ /* But in some case the entry address is 0 */
+ if (pf->addr == 0) {
+ pr_debug("%s has no entry PC. Skipped\n",
+ dwarf_diename(sp_die));
+ param->retval = 0;
/* Real function */
- if (pp->lazy_line)
+ } else if (pp->lazy_line)
param->retval = find_probe_point_lazy(sp_die, pf);
else {
+ skip_prologue(sp_die, pf);
pf->addr += pp->offset;
/* TODO: Check the address in this function */
param->retval = call_probe_finder(sp_die, pf);
@@ -972,7 +1022,7 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
param->retval = die_walk_instances(sp_die,
probe_point_inline_cb, (void *)pf);
/* This could be a non-existed inline definition */
- if (param->retval == -ENOENT && strisglob(pp->function))
+ if (param->retval == -ENOENT)
param->retval = 0;
}
@@ -1101,11 +1151,8 @@ static int debuginfo__find_probes(struct debuginfo *dbg,
struct probe_finder *pf)
{
int ret = 0;
-
-#if _ELFUTILS_PREREQ(0, 142)
Elf *elf;
GElf_Ehdr ehdr;
- GElf_Shdr shdr;
if (pf->cfi_eh || pf->cfi_dbg)
return debuginfo__find_probe_location(dbg, pf);
@@ -1118,11 +1165,18 @@ static int debuginfo__find_probes(struct debuginfo *dbg,
if (gelf_getehdr(elf, &ehdr) == NULL)
return -EINVAL;
- if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) &&
- shdr.sh_type == SHT_PROGBITS)
- pf->cfi_eh = dwarf_getcfi_elf(elf);
+ pf->machine = ehdr.e_machine;
+
+#if _ELFUTILS_PREREQ(0, 142)
+ do {
+ GElf_Shdr shdr;
+
+ if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) &&
+ shdr.sh_type == SHT_PROGBITS)
+ pf->cfi_eh = dwarf_getcfi_elf(elf);
- pf->cfi_dbg = dwarf_getcfi(dbg->dbg);
+ pf->cfi_dbg = dwarf_getcfi(dbg->dbg);
+ } while (0);
#endif
ret = debuginfo__find_probe_location(dbg, pf);
@@ -1150,7 +1204,7 @@ static int copy_variables_cb(Dwarf_Die *die_mem, void *data)
(tag == DW_TAG_variable && vf->vars)) {
if (convert_variable_location(die_mem, vf->pf->addr,
vf->pf->fb_ops, &pf->sp_die,
- NULL) == 0) {
+ pf->machine, NULL) == 0) {
vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem);
if (vf->args[vf->nargs].var == NULL) {
vf->ret = -ENOMEM;
@@ -1313,7 +1367,7 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
tag == DW_TAG_variable) {
ret = convert_variable_location(die_mem, af->pf.addr,
af->pf.fb_ops, &af->pf.sp_die,
- NULL);
+ af->pf.machine, NULL);
if (ret == 0 || ret == -ERANGE) {
int ret2;
bool externs = !af->child;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.