mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 18:09:57 +00:00
perf probe: Fix to probe on gcc generated functions in modules
Fix to probe on gcc generated functions on modules. Since probing on a module is based on its symbol name, it should be adjusted on actual symbols. E.g. without this fix, perf probe shows probe definition on non-exist symbol as below. $ perf probe -m build-x86_64/net/netfilter/nf_nat.ko -F in_range* in_range.isra.12 $ perf probe -m build-x86_64/net/netfilter/nf_nat.ko -D in_range p:probe/in_range nf_nat:in_range+0 With this fix, perf probe correctly shows a probe on gcc-generated symbol. $ perf probe -m build-x86_64/net/netfilter/nf_nat.ko -D in_range p:probe/in_range nf_nat:in_range.isra.12+0 This also fixes same problem on online module as below. $ perf probe -m i915 -D assert_plane p:probe/assert_plane i915:assert_plane.constprop.134+0 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/148411450673.9978.14905987549651656075.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
parent
3e96dac7c9
commit
613f050d68
3 changed files with 37 additions and 18 deletions
|
@ -698,18 +698,31 @@ static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
|
||||
int ntevs, const char *module)
|
||||
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;
|
||||
|
||||
mod_name = find_module_name(module);
|
||||
map = get_target_map(module, 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) {
|
||||
|
@ -719,6 +732,8 @@ static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
|
|||
}
|
||||
|
||||
free(mod_name);
|
||||
map__put(map);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
@ -776,7 +791,7 @@ arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unuse
|
|||
static int post_process_probe_trace_events(struct perf_probe_event *pev,
|
||||
struct probe_trace_event *tevs,
|
||||
int ntevs, const char *module,
|
||||
bool uprobe)
|
||||
bool uprobe, struct debuginfo *dinfo)
|
||||
{
|
||||
int ret;
|
||||
|
||||
|
@ -784,7 +799,8 @@ static int post_process_probe_trace_events(struct perf_probe_event *pev,
|
|||
ret = add_exec_to_probe_trace_events(tevs, ntevs, module);
|
||||
else if (module)
|
||||
/* Currently ref_reloc_sym based probe is not for drivers */
|
||||
ret = add_module_to_probe_trace_events(tevs, ntevs, module);
|
||||
ret = post_process_module_probe_trace_events(tevs, ntevs,
|
||||
module, dinfo);
|
||||
else
|
||||
ret = post_process_kernel_probe_trace_events(tevs, ntevs);
|
||||
|
||||
|
@ -828,30 +844,27 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
|
|||
}
|
||||
}
|
||||
|
||||
debuginfo__delete(dinfo);
|
||||
|
||||
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);
|
||||
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;
|
||||
}
|
||||
if (ret != ntevs)
|
||||
return ret < 0 ? ret : ntevs;
|
||||
ntevs = 0;
|
||||
/* Fall through */
|
||||
}
|
||||
|
||||
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;
|
||||
}
|
||||
/* Error path : ntevs < 0 */
|
||||
pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
|
||||
if (ntevs < 0) {
|
||||
} 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");
|
||||
|
|
|
@ -1501,7 +1501,8 @@ int debuginfo__find_available_vars_at(struct debuginfo *dbg,
|
|||
}
|
||||
|
||||
/* For the kernel module, we need a special code to get a DIE */
|
||||
static int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs)
|
||||
int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
|
||||
bool adjust_offset)
|
||||
{
|
||||
int n, i;
|
||||
Elf32_Word shndx;
|
||||
|
@ -1530,6 +1531,8 @@ static int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs)
|
|||
if (!shdr)
|
||||
return -ENOENT;
|
||||
*offs = shdr->sh_addr;
|
||||
if (adjust_offset)
|
||||
*offs -= shdr->sh_offset;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
|
@ -1545,7 +1548,7 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
|
|||
int baseline = 0, lineno = 0, ret = 0;
|
||||
|
||||
/* We always need to relocate the address for aranges */
|
||||
if (debuginfo__get_text_offset(dbg, &baseaddr) == 0)
|
||||
if (debuginfo__get_text_offset(dbg, &baseaddr, false) == 0)
|
||||
addr += baseaddr;
|
||||
/* Find cu die */
|
||||
if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr, &cudie)) {
|
||||
|
|
|
@ -46,6 +46,9 @@ int debuginfo__find_trace_events(struct debuginfo *dbg,
|
|||
int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
|
||||
struct perf_probe_point *ppt);
|
||||
|
||||
int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
|
||||
bool adjust_offset);
|
||||
|
||||
/* Find a line range */
|
||||
int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr);
|
||||
|
||||
|
|
Loading…
Reference in a new issue