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Diffstat (limited to 'tools/perf/util/probe-finder.c')
-rw-r--r--tools/perf/util/probe-finder.c231
1 files changed, 142 insertions, 89 deletions
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 3e44a3e36519..555fc3864b90 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -612,12 +612,12 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
return ret;
}
-/* Find a variable in a subprogram die */
-static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
+/* Find a variable in a scope DIE */
+static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
{
- Dwarf_Die vr_die, *scopes;
+ Dwarf_Die vr_die;
char buf[32], *ptr;
- int ret, nscopes;
+ int ret = 0;
if (!is_c_varname(pf->pvar->var)) {
/* Copy raw parameters */
@@ -652,30 +652,16 @@ static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
if (pf->tvar->name == NULL)
return -ENOMEM;
- pr_debug("Searching '%s' variable in context.\n",
- pf->pvar->var);
+ pr_debug("Searching '%s' variable in context.\n", pf->pvar->var);
/* Search child die for local variables and parameters. */
- if (die_find_variable_at(sp_die, pf->pvar->var, pf->addr, &vr_die))
- ret = convert_variable(&vr_die, pf);
- else {
- /* Search upper class */
- nscopes = dwarf_getscopes_die(sp_die, &scopes);
- while (nscopes-- > 1) {
- pr_debug("Searching variables in %s\n",
- dwarf_diename(&scopes[nscopes]));
- /* We should check this scope, so give dummy address */
- if (die_find_variable_at(&scopes[nscopes],
- pf->pvar->var, 0,
- &vr_die)) {
- ret = convert_variable(&vr_die, pf);
- goto found;
- }
- }
- if (scopes)
- free(scopes);
- ret = -ENOENT;
+ if (!die_find_variable_at(sc_die, pf->pvar->var, pf->addr, &vr_die)) {
+ /* Search again in global variables */
+ if (!die_find_variable_at(&pf->cu_die, pf->pvar->var, 0, &vr_die))
+ ret = -ENOENT;
}
-found:
+ if (ret == 0)
+ ret = convert_variable(&vr_die, pf);
+
if (ret < 0)
pr_warning("Failed to find '%s' in this function.\n",
pf->pvar->var);
@@ -718,26 +704,30 @@ static int convert_to_trace_point(Dwarf_Die *sp_die, Dwarf_Addr paddr,
return 0;
}
-/* Call probe_finder callback with real subprogram DIE */
-static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf)
+/* Call probe_finder callback with scope DIE */
+static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf)
{
- Dwarf_Die die_mem;
Dwarf_Attribute fb_attr;
size_t nops;
int ret;
- /* If no real subprogram, find a real one */
- if (!sp_die || dwarf_tag(sp_die) != DW_TAG_subprogram) {
- sp_die = die_find_realfunc(&pf->cu_die, pf->addr, &die_mem);
- if (!sp_die) {
+ if (!sc_die) {
+ pr_err("Caller must pass a scope DIE. Program error.\n");
+ return -EINVAL;
+ }
+
+ /* If not a real subprogram, find a real one */
+ if (dwarf_tag(sc_die) != DW_TAG_subprogram) {
+ if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
pr_warning("Failed to find probe point in any "
"functions.\n");
return -ENOENT;
}
- }
+ } else
+ memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die));
- /* Get the frame base attribute/ops */
- dwarf_attr(sp_die, DW_AT_frame_base, &fb_attr);
+ /* Get the frame base attribute/ops from subprogram */
+ dwarf_attr(&pf->sp_die, DW_AT_frame_base, &fb_attr);
ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
if (ret <= 0 || nops == 0) {
pf->fb_ops = NULL;
@@ -755,7 +745,7 @@ static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf)
}
/* Call finder's callback handler */
- ret = pf->callback(sp_die, pf);
+ ret = pf->callback(sc_die, pf);
/* *pf->fb_ops will be cached in libdw. Don't free it. */
pf->fb_ops = NULL;
@@ -763,17 +753,82 @@ static int call_probe_finder(Dwarf_Die *sp_die, struct probe_finder *pf)
return ret;
}
+struct find_scope_param {
+ const char *function;
+ const char *file;
+ int line;
+ int diff;
+ Dwarf_Die *die_mem;
+ bool found;
+};
+
+static int find_best_scope_cb(Dwarf_Die *fn_die, void *data)
+{
+ struct find_scope_param *fsp = data;
+ const char *file;
+ int lno;
+
+ /* Skip if declared file name does not match */
+ if (fsp->file) {
+ file = dwarf_decl_file(fn_die);
+ if (!file || strcmp(fsp->file, file) != 0)
+ return 0;
+ }
+ /* If the function name is given, that's what user expects */
+ if (fsp->function) {
+ if (die_compare_name(fn_die, fsp->function)) {
+ memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
+ fsp->found = true;
+ return 1;
+ }
+ } else {
+ /* With the line number, find the nearest declared DIE */
+ dwarf_decl_line(fn_die, &lno);
+ if (lno < fsp->line && fsp->diff > fsp->line - lno) {
+ /* Keep a candidate and continue */
+ fsp->diff = fsp->line - lno;
+ memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
+ fsp->found = true;
+ }
+ }
+ return 0;
+}
+
+/* Find an appropriate scope fits to given conditions */
+static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem)
+{
+ struct find_scope_param fsp = {
+ .function = pf->pev->point.function,
+ .file = pf->fname,
+ .line = pf->lno,
+ .diff = INT_MAX,
+ .die_mem = die_mem,
+ .found = false,
+ };
+
+ cu_walk_functions_at(&pf->cu_die, pf->addr, find_best_scope_cb, &fsp);
+
+ return fsp.found ? die_mem : NULL;
+}
+
static int probe_point_line_walker(const char *fname, int lineno,
Dwarf_Addr addr, void *data)
{
struct probe_finder *pf = data;
+ Dwarf_Die *sc_die, die_mem;
int ret;
if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
return 0;
pf->addr = addr;
- ret = call_probe_finder(NULL, pf);
+ sc_die = find_best_scope(pf, &die_mem);
+ if (!sc_die) {
+ pr_warning("Failed to find scope of probe point.\n");
+ return -ENOENT;
+ }
+
+ ret = call_probe_finder(sc_die, pf);
/* Continue if no error, because the line will be in inline function */
return ret < 0 ? ret : 0;
@@ -827,6 +882,7 @@ static int probe_point_lazy_walker(const char *fname, int lineno,
Dwarf_Addr addr, void *data)
{
struct probe_finder *pf = data;
+ Dwarf_Die *sc_die, die_mem;
int ret;
if (!line_list__has_line(&pf->lcache, lineno) ||
@@ -836,7 +892,14 @@ static int probe_point_lazy_walker(const char *fname, int lineno,
pr_debug("Probe line found: line:%d addr:0x%llx\n",
lineno, (unsigned long long)addr);
pf->addr = addr;
- ret = call_probe_finder(NULL, pf);
+ pf->lno = lineno;
+ sc_die = find_best_scope(pf, &die_mem);
+ if (!sc_die) {
+ pr_warning("Failed to find scope of probe point.\n");
+ return -ENOENT;
+ }
+
+ ret = call_probe_finder(sc_die, pf);
/*
* Continue if no error, because the lazy pattern will match
@@ -861,42 +924,39 @@ 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);
}
-/* 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 dwarf_callback_param *param = data;
- struct probe_finder *pf = param->data;
+ struct probe_finder *pf = data;
struct perf_probe_point *pp = &pf->pev->point;
Dwarf_Addr addr;
+ int ret;
if (pp->lazy_line)
- param->retval = find_probe_point_lazy(in_die, pf);
+ ret = find_probe_point_lazy(in_die, pf);
else {
/* Get probe address */
if (dwarf_entrypc(in_die, &addr) != 0) {
pr_warning("Failed to get entry address of %s.\n",
dwarf_diename(in_die));
- param->retval = -ENOENT;
- return DWARF_CB_ABORT;
+ return -ENOENT;
}
pf->addr = addr;
pf->addr += pp->offset;
pr_debug("found inline addr: 0x%jx\n",
(uintmax_t)pf->addr);
- param->retval = call_probe_finder(in_die, pf);
- if (param->retval < 0)
- return DWARF_CB_ABORT;
+ ret = call_probe_finder(in_die, pf);
}
- return DWARF_CB_OK;
+ return ret;
}
+/* Callback parameter with return value for libdw */
+struct dwarf_callback_param {
+ void *data;
+ int retval;
+};
+
/* Search function from function name */
static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
{
@@ -933,14 +993,10 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
/* TODO: Check the address in this function */
param->retval = call_probe_finder(sp_die, pf);
}
- } else {
- struct dwarf_callback_param _param = {.data = (void *)pf,
- .retval = 0};
+ } else
/* Inlined function: search instances */
- dwarf_func_inline_instances(sp_die, probe_point_inline_cb,
- &_param);
- param->retval = _param.retval;
- }
+ param->retval = die_walk_instances(sp_die,
+ probe_point_inline_cb, (void *)pf);
return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
}
@@ -1060,7 +1116,7 @@ found:
}
/* Add a found probe point into trace event list */
-static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf)
+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);
@@ -1075,8 +1131,9 @@ static int add_probe_trace_event(Dwarf_Die *sp_die, struct probe_finder *pf)
}
tev = &tf->tevs[tf->ntevs++];
- ret = convert_to_trace_point(sp_die, pf->addr, pf->pev->point.retprobe,
- &tev->point);
+ /* Trace point should be converted from subprogram DIE */
+ ret = convert_to_trace_point(&pf->sp_die, pf->addr,
+ pf->pev->point.retprobe, &tev->point);
if (ret < 0)
return ret;
@@ -1091,7 +1148,8 @@ static int add_probe_trace_event(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];
- ret = find_variable(sp_die, pf);
+ /* Variable should be found from scope DIE */
+ ret = find_variable(sc_die, pf);
if (ret != 0)
return ret;
}
@@ -1159,13 +1217,13 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
}
/* Add a found vars into available variables list */
-static int add_available_vars(Dwarf_Die *sp_die, struct probe_finder *pf)
+static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
{
struct available_var_finder *af =
container_of(pf, struct available_var_finder, pf);
struct variable_list *vl;
- Dwarf_Die die_mem, *scopes = NULL;
- int ret, nscopes;
+ Dwarf_Die die_mem;
+ int ret;
/* Check number of tevs */
if (af->nvls == af->max_vls) {
@@ -1174,8 +1232,9 @@ static int add_available_vars(Dwarf_Die *sp_die, struct probe_finder *pf)
}
vl = &af->vls[af->nvls++];
- ret = convert_to_trace_point(sp_die, pf->addr, pf->pev->point.retprobe,
- &vl->point);
+ /* Trace point should be converted from subprogram DIE */
+ ret = convert_to_trace_point(&pf->sp_die, pf->addr,
+ pf->pev->point.retprobe, &vl->point);
if (ret < 0)
return ret;
@@ -1187,19 +1246,14 @@ static int add_available_vars(Dwarf_Die *sp_die, struct probe_finder *pf)
if (vl->vars == NULL)
return -ENOMEM;
af->child = true;
- die_find_child(sp_die, collect_variables_cb, (void *)af, &die_mem);
+ die_find_child(sc_die, collect_variables_cb, (void *)af, &die_mem);
/* Find external variables */
if (!af->externs)
goto out;
/* Don't need to search child DIE for externs. */
af->child = false;
- nscopes = dwarf_getscopes_die(sp_die, &scopes);
- while (nscopes-- > 1)
- die_find_child(&scopes[nscopes], collect_variables_cb,
- (void *)af, &die_mem);
- if (scopes)
- free(scopes);
+ die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem);
out:
if (strlist__empty(vl->vars)) {
@@ -1391,10 +1445,14 @@ static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
{
- struct dwarf_callback_param *param = data;
+ find_line_range_by_line(in_die, data);
- param->retval = find_line_range_by_line(in_die, param->data);
- return DWARF_CB_ABORT; /* No need to find other instances */
+ /*
+ * We have to check all instances of inlined function, because
+ * some execution paths can be optimized out depends on the
+ * function argument of instances
+ */
+ return 0;
}
/* Search function from function name */
@@ -1422,15 +1480,10 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
lr->start = lf->lno_s;
lr->end = lf->lno_e;
- 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,
- &_param);
- param->retval = _param.retval;
- } else
+ if (dwarf_func_inline(sp_die))
+ param->retval = die_walk_instances(sp_die,
+ line_range_inline_cb, lf);
+ else
param->retval = find_line_range_by_line(sp_die, lf);
return DWARF_CB_ABORT;
}
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