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Diffstat (limited to 'tools/perf/util/probe-finder.c')
-rw-r--r--tools/perf/util/probe-finder.c297
1 files changed, 209 insertions, 88 deletions
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 371476cb8dd..ffb657ffd32 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -115,7 +115,7 @@ static const Dwfl_Callbacks offline_callbacks = {
};
/* Get a Dwarf from offline image */
-static int debuginfo__init_offline_dwarf(struct debuginfo *self,
+static int debuginfo__init_offline_dwarf(struct debuginfo *dbg,
const char *path)
{
int fd;
@@ -124,25 +124,25 @@ static int debuginfo__init_offline_dwarf(struct debuginfo *self,
if (fd < 0)
return fd;
- self->dwfl = dwfl_begin(&offline_callbacks);
- if (!self->dwfl)
+ dbg->dwfl = dwfl_begin(&offline_callbacks);
+ if (!dbg->dwfl)
goto error;
- self->mod = dwfl_report_offline(self->dwfl, "", "", fd);
- if (!self->mod)
+ dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd);
+ if (!dbg->mod)
goto error;
- self->dbg = dwfl_module_getdwarf(self->mod, &self->bias);
- if (!self->dbg)
+ dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias);
+ if (!dbg->dbg)
goto error;
return 0;
error:
- if (self->dwfl)
- dwfl_end(self->dwfl);
+ if (dbg->dwfl)
+ dwfl_end(dbg->dwfl);
else
close(fd);
- memset(self, 0, sizeof(*self));
+ memset(dbg, 0, sizeof(*dbg));
return -ENOENT;
}
@@ -180,24 +180,24 @@ static const Dwfl_Callbacks kernel_callbacks = {
};
/* Get a Dwarf from live kernel image */
-static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
+static int debuginfo__init_online_kernel_dwarf(struct debuginfo *dbg,
Dwarf_Addr addr)
{
- self->dwfl = dwfl_begin(&kernel_callbacks);
- if (!self->dwfl)
+ dbg->dwfl = dwfl_begin(&kernel_callbacks);
+ if (!dbg->dwfl)
return -EINVAL;
/* Load the kernel dwarves: Don't care the result here */
- dwfl_linux_kernel_report_kernel(self->dwfl);
- dwfl_linux_kernel_report_modules(self->dwfl);
+ dwfl_linux_kernel_report_kernel(dbg->dwfl);
+ dwfl_linux_kernel_report_modules(dbg->dwfl);
- self->dbg = dwfl_addrdwarf(self->dwfl, addr, &self->bias);
+ dbg->dbg = dwfl_addrdwarf(dbg->dwfl, addr, &dbg->bias);
/* Here, check whether we could get a real dwarf */
- if (!self->dbg) {
+ if (!dbg->dbg) {
pr_debug("Failed to find kernel dwarf at %lx\n",
(unsigned long)addr);
- dwfl_end(self->dwfl);
- memset(self, 0, sizeof(*self));
+ dwfl_end(dbg->dwfl);
+ memset(dbg, 0, sizeof(*dbg));
return -ENOENT;
}
@@ -205,7 +205,7 @@ static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
}
#else
/* With older elfutils, this just support kernel module... */
-static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
+static int debuginfo__init_online_kernel_dwarf(struct debuginfo *dbg,
Dwarf_Addr addr __maybe_unused)
{
const char *path = kernel_get_module_path("kernel");
@@ -216,44 +216,45 @@ static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
}
pr_debug2("Use file %s for debuginfo\n", path);
- return debuginfo__init_offline_dwarf(self, path);
+ return debuginfo__init_offline_dwarf(dbg, path);
}
#endif
struct debuginfo *debuginfo__new(const char *path)
{
- struct debuginfo *self = zalloc(sizeof(struct debuginfo));
- if (!self)
+ struct debuginfo *dbg = zalloc(sizeof(*dbg));
+ if (!dbg)
return NULL;
- if (debuginfo__init_offline_dwarf(self, path) < 0) {
- free(self);
- self = NULL;
+ if (debuginfo__init_offline_dwarf(dbg, path) < 0) {
+ free(dbg);
+ dbg = NULL;
}
- return self;
+ return dbg;
}
struct debuginfo *debuginfo__new_online_kernel(unsigned long addr)
{
- struct debuginfo *self = zalloc(sizeof(struct debuginfo));
- if (!self)
+ struct debuginfo *dbg = zalloc(sizeof(*dbg));
+
+ if (!dbg)
return NULL;
- if (debuginfo__init_online_kernel_dwarf(self, (Dwarf_Addr)addr) < 0) {
- free(self);
- self = NULL;
+ if (debuginfo__init_online_kernel_dwarf(dbg, (Dwarf_Addr)addr) < 0) {
+ free(dbg);
+ dbg = NULL;
}
- return self;
+ return dbg;
}
-void debuginfo__delete(struct debuginfo *self)
+void debuginfo__delete(struct debuginfo *dbg)
{
- if (self) {
- if (self->dwfl)
- dwfl_end(self->dwfl);
- free(self);
+ if (dbg) {
+ if (dbg->dwfl)
+ dwfl_end(dbg->dwfl);
+ free(dbg);
}
}
@@ -273,12 +274,15 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
/*
* Convert a location into trace_arg.
* If tvar == NULL, this just checks variable can be converted.
+ * If fentry == true and vr_die is a parameter, do huristic search
+ * for the location fuzzed by function entry mcount.
*/
static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
- Dwarf_Op *fb_ops,
+ Dwarf_Op *fb_ops, Dwarf_Die *sp_die,
struct probe_trace_arg *tvar)
{
Dwarf_Attribute attr;
+ Dwarf_Addr tmp = 0;
Dwarf_Op *op;
size_t nops;
unsigned int regn;
@@ -291,12 +295,29 @@ static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
goto static_var;
/* TODO: handle more than 1 exprs */
- if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL ||
- dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0 ||
- nops == 0) {
- /* TODO: Support const_value */
+ if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
+ return -EINVAL; /* Broken DIE ? */
+ if (dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0) {
+ ret = dwarf_entrypc(sp_die, &tmp);
+ if (ret || addr != tmp ||
+ dwarf_tag(vr_die) != DW_TAG_formal_parameter ||
+ dwarf_highpc(sp_die, &tmp))
+ return -ENOENT;
+ /*
+ * This is fuzzed by fentry mcount. We try to find the
+ * parameter location at the earliest address.
+ */
+ for (addr += 1; addr <= tmp; addr++) {
+ if (dwarf_getlocation_addr(&attr, addr, &op,
+ &nops, 1) > 0)
+ goto found;
+ }
return -ENOENT;
}
+found:
+ if (nops == 0)
+ /* TODO: Support const_value */
+ return -ENOENT;
if (op->atom == DW_OP_addr) {
static_var:
@@ -563,7 +584,7 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
}
if (die_find_member(&type, field->name, die_mem) == NULL) {
- pr_warning("%s(tyep:%s) has no member %s.\n", varname,
+ pr_warning("%s(type:%s) has no member %s.\n", varname,
dwarf_diename(&type), field->name);
return -EINVAL;
}
@@ -600,7 +621,7 @@ 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->tvar);
+ &pf->sp_die, pf->tvar);
if (ret == -ENOENT)
pr_err("Failed to find the location of %s at this address.\n"
" Perhaps, it has been optimized out.\n", pf->pvar->var);
@@ -1063,7 +1084,7 @@ static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
}
/* Find probe points from debuginfo */
-static int debuginfo__find_probes(struct debuginfo *self,
+static int debuginfo__find_probes(struct debuginfo *dbg,
struct probe_finder *pf)
{
struct perf_probe_point *pp = &pf->pev->point;
@@ -1074,7 +1095,7 @@ static int debuginfo__find_probes(struct debuginfo *self,
#if _ELFUTILS_PREREQ(0, 142)
/* Get the call frame information from this dwarf */
- pf->cfi = dwarf_getcfi(self->dbg);
+ pf->cfi = dwarf_getcfi(dbg->dbg);
#endif
off = 0;
@@ -1093,7 +1114,7 @@ static int debuginfo__find_probes(struct debuginfo *self,
.data = pf,
};
- dwarf_getpubnames(self->dbg, pubname_search_cb,
+ dwarf_getpubnames(dbg->dbg, pubname_search_cb,
&pubname_param, 0);
if (pubname_param.found) {
ret = probe_point_search_cb(&pf->sp_die, &probe_param);
@@ -1103,9 +1124,9 @@ static int debuginfo__find_probes(struct debuginfo *self,
}
/* Loop on CUs (Compilation Unit) */
- while (!dwarf_nextcu(self->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
+ while (!dwarf_nextcu(dbg->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
/* Get the DIE(Debugging Information Entry) of this CU */
- diep = dwarf_offdie(self->dbg, off + cuhl, &pf->cu_die);
+ diep = dwarf_offdie(dbg->dbg, off + cuhl, &pf->cu_die);
if (!diep)
continue;
@@ -1136,12 +1157,80 @@ found:
return ret;
}
+struct local_vars_finder {
+ struct probe_finder *pf;
+ struct perf_probe_arg *args;
+ int max_args;
+ int nargs;
+ int ret;
+};
+
+/* Collect available variables in this scope */
+static int copy_variables_cb(Dwarf_Die *die_mem, void *data)
+{
+ struct local_vars_finder *vf = data;
+ struct probe_finder *pf = vf->pf;
+ int tag;
+
+ tag = dwarf_tag(die_mem);
+ if (tag == DW_TAG_formal_parameter ||
+ tag == DW_TAG_variable) {
+ if (convert_variable_location(die_mem, vf->pf->addr,
+ vf->pf->fb_ops, &pf->sp_die,
+ NULL) == 0) {
+ vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem);
+ if (vf->args[vf->nargs].var == NULL) {
+ vf->ret = -ENOMEM;
+ return DIE_FIND_CB_END;
+ }
+ pr_debug(" %s", vf->args[vf->nargs].var);
+ vf->nargs++;
+ }
+ }
+
+ if (dwarf_haspc(die_mem, vf->pf->addr))
+ return DIE_FIND_CB_CONTINUE;
+ else
+ return DIE_FIND_CB_SIBLING;
+}
+
+static int expand_probe_args(Dwarf_Die *sc_die, struct probe_finder *pf,
+ struct perf_probe_arg *args)
+{
+ Dwarf_Die die_mem;
+ int i;
+ int n = 0;
+ struct local_vars_finder vf = {.pf = pf, .args = args,
+ .max_args = MAX_PROBE_ARGS, .ret = 0};
+
+ for (i = 0; i < pf->pev->nargs; i++) {
+ /* var never be NULL */
+ if (strcmp(pf->pev->args[i].var, "$vars") == 0) {
+ pr_debug("Expanding $vars into:");
+ vf.nargs = n;
+ /* Special local variables */
+ die_find_child(sc_die, copy_variables_cb, (void *)&vf,
+ &die_mem);
+ pr_debug(" (%d)\n", vf.nargs - n);
+ if (vf.ret < 0)
+ return vf.ret;
+ n = vf.nargs;
+ } else {
+ /* Copy normal argument */
+ args[n] = pf->pev->args[i];
+ n++;
+ }
+ }
+ return n;
+}
+
/* Add a found probe point into trace event list */
static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
{
struct trace_event_finder *tf =
container_of(pf, struct trace_event_finder, pf);
struct probe_trace_event *tev;
+ struct perf_probe_arg *args;
int ret, i;
/* Check number of tevs */
@@ -1161,31 +1250,45 @@ static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
tev->point.offset);
- /* Find each argument */
- tev->nargs = pf->pev->nargs;
- tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
- if (tev->args == NULL)
+ /* Expand special probe argument if exist */
+ args = zalloc(sizeof(struct perf_probe_arg) * MAX_PROBE_ARGS);
+ if (args == NULL)
return -ENOMEM;
- for (i = 0; i < pf->pev->nargs; i++) {
- pf->pvar = &pf->pev->args[i];
+
+ ret = expand_probe_args(sc_die, pf, args);
+ if (ret < 0)
+ goto end;
+
+ tev->nargs = ret;
+ tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
+ if (tev->args == NULL) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ /* Find each argument */
+ for (i = 0; i < tev->nargs; i++) {
+ pf->pvar = &args[i];
pf->tvar = &tev->args[i];
/* Variable should be found from scope DIE */
ret = find_variable(sc_die, pf);
if (ret != 0)
- return ret;
+ break;
}
- return 0;
+end:
+ free(args);
+ return ret;
}
/* Find probe_trace_events specified by perf_probe_event from debuginfo */
-int debuginfo__find_trace_events(struct debuginfo *self,
+int debuginfo__find_trace_events(struct debuginfo *dbg,
struct perf_probe_event *pev,
struct probe_trace_event **tevs, int max_tevs)
{
struct trace_event_finder tf = {
.pf = {.pev = pev, .callback = add_probe_trace_event},
- .mod = self->mod, .max_tevs = max_tevs};
+ .mod = dbg->mod, .max_tevs = max_tevs};
int ret;
/* Allocate result tevs array */
@@ -1196,7 +1299,7 @@ int debuginfo__find_trace_events(struct debuginfo *self,
tf.tevs = *tevs;
tf.ntevs = 0;
- ret = debuginfo__find_probes(self, &tf.pf);
+ ret = debuginfo__find_probes(dbg, &tf.pf);
if (ret < 0) {
free(*tevs);
*tevs = NULL;
@@ -1222,7 +1325,8 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
if (tag == DW_TAG_formal_parameter ||
tag == DW_TAG_variable) {
ret = convert_variable_location(die_mem, af->pf.addr,
- af->pf.fb_ops, NULL);
+ af->pf.fb_ops, &af->pf.sp_die,
+ NULL);
if (ret == 0) {
ret = die_get_varname(die_mem, buf, MAX_VAR_LEN);
pr_debug2("Add new var: %s\n", buf);
@@ -1286,14 +1390,14 @@ out:
}
/* Find available variables at given probe point */
-int debuginfo__find_available_vars_at(struct debuginfo *self,
+int debuginfo__find_available_vars_at(struct debuginfo *dbg,
struct perf_probe_event *pev,
struct variable_list **vls,
int max_vls, bool externs)
{
struct available_var_finder af = {
.pf = {.pev = pev, .callback = add_available_vars},
- .mod = self->mod,
+ .mod = dbg->mod,
.max_vls = max_vls, .externs = externs};
int ret;
@@ -1305,7 +1409,7 @@ int debuginfo__find_available_vars_at(struct debuginfo *self,
af.vls = *vls;
af.nvls = 0;
- ret = debuginfo__find_probes(self, &af.pf);
+ ret = debuginfo__find_probes(dbg, &af.pf);
if (ret < 0) {
/* Free vlist for error */
while (af.nvls--) {
@@ -1323,19 +1427,19 @@ int debuginfo__find_available_vars_at(struct debuginfo *self,
}
/* Reverse search */
-int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
+int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
struct perf_probe_point *ppt)
{
Dwarf_Die cudie, spdie, indie;
- Dwarf_Addr _addr, baseaddr;
- const char *fname = NULL, *func = NULL, *tmp;
+ Dwarf_Addr _addr = 0, baseaddr = 0;
+ const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp;
int baseline = 0, lineno = 0, ret = 0;
/* Adjust address with bias */
- addr += self->bias;
+ addr += dbg->bias;
/* Find cu die */
- if (!dwarf_addrdie(self->dbg, (Dwarf_Addr)addr - self->bias, &cudie)) {
+ if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr - dbg->bias, &cudie)) {
pr_warning("Failed to find debug information for address %lx\n",
addr);
ret = -EINVAL;
@@ -1349,27 +1453,36 @@ int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
/* Find a corresponding function (name, baseline and baseaddr) */
if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
/* Get function entry information */
- tmp = dwarf_diename(&spdie);
- if (!tmp ||
+ func = basefunc = dwarf_diename(&spdie);
+ if (!func ||
dwarf_entrypc(&spdie, &baseaddr) != 0 ||
- dwarf_decl_line(&spdie, &baseline) != 0)
+ dwarf_decl_line(&spdie, &baseline) != 0) {
+ lineno = 0;
goto post;
- func = tmp;
+ }
- if (addr == (unsigned long)baseaddr)
+ fname = dwarf_decl_file(&spdie);
+ if (addr == (unsigned long)baseaddr) {
/* Function entry - Relative line number is 0 */
lineno = baseline;
- else if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
- &indie)) {
+ goto post;
+ }
+
+ /* Track down the inline functions step by step */
+ while (die_find_top_inlinefunc(&spdie, (Dwarf_Addr)addr,
+ &indie)) {
+ /* There is an inline function */
if (dwarf_entrypc(&indie, &_addr) == 0 &&
- _addr == addr)
+ _addr == addr) {
/*
* addr is at an inline function entry.
* In this case, lineno should be the call-site
- * line number.
+ * line number. (overwrite lineinfo)
*/
lineno = die_get_call_lineno(&indie);
- else {
+ fname = die_get_call_file(&indie);
+ break;
+ } else {
/*
* addr is in an inline function body.
* Since lineno points one of the lines
@@ -1377,19 +1490,27 @@ int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
* be the entry line of the inline function.
*/
tmp = dwarf_diename(&indie);
- if (tmp &&
- dwarf_decl_line(&spdie, &baseline) == 0)
- func = tmp;
+ if (!tmp ||
+ dwarf_decl_line(&indie, &baseline) != 0)
+ break;
+ func = tmp;
+ spdie = indie;
}
}
+ /* Verify the lineno and baseline are in a same file */
+ tmp = dwarf_decl_file(&spdie);
+ if (!tmp || strcmp(tmp, fname) != 0)
+ lineno = 0;
}
post:
/* Make a relative line number or an offset */
if (lineno)
ppt->line = lineno - baseline;
- else if (func)
+ else if (basefunc) {
ppt->offset = addr - (unsigned long)baseaddr;
+ func = basefunc;
+ }
/* Duplicate strings */
if (func) {
@@ -1519,7 +1640,7 @@ static int find_line_range_by_func(struct line_finder *lf)
return param.retval;
}
-int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
+int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr)
{
struct line_finder lf = {.lr = lr, .found = 0};
int ret = 0;
@@ -1536,7 +1657,7 @@ int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
struct dwarf_callback_param line_range_param = {
.data = (void *)&lf, .retval = 0};
- dwarf_getpubnames(self->dbg, pubname_search_cb,
+ dwarf_getpubnames(dbg->dbg, pubname_search_cb,
&pubname_param, 0);
if (pubname_param.found) {
line_range_search_cb(&lf.sp_die, &line_range_param);
@@ -1547,12 +1668,12 @@ int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
/* Loop on CUs (Compilation Unit) */
while (!lf.found && ret >= 0) {
- if (dwarf_nextcu(self->dbg, off, &noff, &cuhl,
+ if (dwarf_nextcu(dbg->dbg, off, &noff, &cuhl,
NULL, NULL, NULL) != 0)
break;
/* Get the DIE(Debugging Information Entry) of this CU */
- diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die);
+ diep = dwarf_offdie(dbg->dbg, off + cuhl, &lf.cu_die);
if (!diep)
continue;