[PATCH 08/23] perf annotate-data: Add debug messages

From: Namhyung Kim
Date: Tue Mar 19 2024 - 01:53:09 EST


Add a new debug option "type-profile" to enable the detailed info during
the type analysis especially for instruction tracking. You can use this
before the command name like 'report' or 'annotate'.

$ perf --debug type-profile annotate --data-type

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/annotate-data.c | 74 +++++++++++++++++++++++++++++----
tools/perf/util/debug.c | 3 ++
tools/perf/util/debug.h | 1 +
3 files changed, 71 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c
index ff81d164aa57..f482ccfdaa91 100644
--- a/tools/perf/util/annotate-data.c
+++ b/tools/perf/util/annotate-data.c
@@ -23,6 +23,29 @@
#include "symbol.h"
#include "symbol_conf.h"

+#define pr_debug_dtp(fmt, ...) \
+do { \
+ if (debug_type_profile) \
+ pr_info(fmt, ##__VA_ARGS__); \
+ else \
+ pr_debug3(fmt, ##__VA_ARGS__); \
+} while (0)
+
+static void pr_debug_type_name(Dwarf_Die *die)
+{
+ struct strbuf sb;
+ char *str;
+
+ if (!debug_type_profile && verbose < 3)
+ return;
+
+ strbuf_init(&sb, 32);
+ die_get_typename_from_type(die, &sb);
+ str = strbuf_detach(&sb, NULL);
+ pr_info(" type=%s (die:%lx)\n", str, (long)dwarf_dieoffset(die));
+ free(str);
+}
+
/*
* Compare type name and size to maintain them in a tree.
* I'm not sure if DWARF would have information of a single type in many
@@ -201,7 +224,7 @@ static int check_variable(Dwarf_Die *var_die, Dwarf_Die *type_die, int offset,

/* Get the type of the variable */
if (die_get_real_type(var_die, type_die) == NULL) {
- pr_debug("variable has no type\n");
+ pr_debug_dtp("variable has no type\n");
ann_data_stat.no_typeinfo++;
return -1;
}
@@ -215,7 +238,7 @@ static int check_variable(Dwarf_Die *var_die, Dwarf_Die *type_die, int offset,
if ((dwarf_tag(type_die) != DW_TAG_pointer_type &&
dwarf_tag(type_die) != DW_TAG_array_type) ||
die_get_real_type(type_die, type_die) == NULL) {
- pr_debug("no pointer or no type\n");
+ pr_debug_dtp("no pointer or no type\n");
ann_data_stat.no_typeinfo++;
return -1;
}
@@ -223,14 +246,15 @@ static int check_variable(Dwarf_Die *var_die, Dwarf_Die *type_die, int offset,

/* Get the size of the actual type */
if (dwarf_aggregate_size(type_die, &size) < 0) {
- pr_debug("type size is unknown\n");
+ pr_debug_dtp("type size is unknown\n");
ann_data_stat.invalid_size++;
return -1;
}

/* Minimal sanity check */
if ((unsigned)offset >= size) {
- pr_debug("offset: %d is bigger than size: %" PRIu64 "\n", offset, size);
+ pr_debug_dtp("offset: %d is bigger than size: %"PRIu64"\n",
+ offset, size);
ann_data_stat.bad_offset++;
return -1;
}
@@ -251,6 +275,19 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
int fb_offset = 0;
bool is_fbreg = false;
u64 pc;
+ char buf[64];
+
+ if (dloc->op->multi_regs)
+ snprintf(buf, sizeof(buf), " or reg%d", dloc->op->reg2);
+ else if (dloc->op->reg1 == DWARF_REG_PC)
+ snprintf(buf, sizeof(buf), " (PC)");
+ else
+ buf[0] = '\0';
+
+ pr_debug_dtp("-----------------------------------------------------------\n");
+ pr_debug_dtp("%s [%"PRIx64"] for reg%d%s offset=%#x in %s\n",
+ __func__, dloc->ip - dloc->ms->sym->start,
+ dloc->op->reg1, buf, dloc->op->offset, dloc->ms->sym->name);

/*
* IP is a relative instruction address from the start of the map, as
@@ -261,7 +298,7 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)

/* Get a compile_unit for this address */
if (!find_cu_die(dloc->di, pc, &cu_die)) {
- pr_debug("cannot find CU for address %" PRIx64 "\n", pc);
+ pr_debug_dtp("cannot find CU for address %"PRIx64"\n", pc);
ann_data_stat.no_cuinfo++;
return -1;
}
@@ -269,12 +306,17 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
reg = loc->reg1;
offset = loc->offset;

+ pr_debug_dtp("CU die offset: %#lx\n", (long)dwarf_dieoffset(&cu_die));
+
if (reg == DWARF_REG_PC) {
if (die_find_variable_by_addr(&cu_die, dloc->var_addr, &var_die,
&offset)) {
ret = check_variable(&var_die, type_die, offset,
/*is_pointer=*/false);
dloc->type_offset = offset;
+
+ pr_debug_dtp("found PC-rel by addr=%#"PRIx64" offset=%#x\n",
+ dloc->var_addr, offset);
goto out;
}

@@ -310,6 +352,9 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
default:
break;
}
+
+ pr_debug_dtp("frame base: cfa=%d fbreg=%d\n",
+ dloc->fb_cfa, fbreg);
}
}

@@ -334,6 +379,19 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
/* Found a variable, see if it's correct */
ret = check_variable(&var_die, type_die, offset,
reg != DWARF_REG_PC && !is_fbreg);
+ if (ret == 0) {
+ pr_debug_dtp("found \"%s\" in scope=%d/%d (die: %#lx) ",
+ dwarf_diename(&var_die), i+1, nr_scopes,
+ (long)dwarf_dieoffset(&scopes[i]));
+ if (reg == DWARF_REG_PC)
+ pr_debug_dtp("%#x(PC) offset=%#x", loc->offset, offset);
+ else if (reg == DWARF_REG_FB || is_fbreg)
+ pr_debug_dtp("%#x(reg%d) stack fb_offset=%#x offset=%#x",
+ loc->offset, reg, fb_offset, offset);
+ else
+ pr_debug_dtp("%#x(reg%d)", loc->offset, reg);
+ pr_debug_type_name(type_die);
+ }
dloc->type_offset = offset;
goto out;
}
@@ -343,8 +401,10 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
goto retry;
}

- if (ret < 0)
+ if (ret < 0) {
+ pr_debug_dtp("no variable found\n");
ann_data_stat.no_var++;
+ }

out:
free(scopes);
@@ -373,7 +433,7 @@ struct annotated_data_type *find_data_type(struct data_loc_info *dloc)

dloc->di = debuginfo__new(dso->long_name);
if (dloc->di == NULL) {
- pr_debug("cannot get the debug info\n");
+ pr_debug_dtp("cannot get the debug info\n");
return NULL;
}

diff --git a/tools/perf/util/debug.c b/tools/perf/util/debug.c
index c39ee0fcb8cf..d633d15329fa 100644
--- a/tools/perf/util/debug.c
+++ b/tools/perf/util/debug.c
@@ -41,6 +41,7 @@ static int redirect_to_stderr;
int debug_data_convert;
static FILE *_debug_file;
bool debug_display_time;
+int debug_type_profile;

FILE *debug_file(void)
{
@@ -231,6 +232,7 @@ static struct sublevel_option debug_opts[] = {
{ .name = "data-convert", .value_ptr = &debug_data_convert },
{ .name = "perf-event-open", .value_ptr = &debug_peo_args },
{ .name = "kmaps", .value_ptr = &debug_kmaps },
+ { .name = "type-profile", .value_ptr = &debug_type_profile },
{ .name = NULL, }
};

@@ -270,6 +272,7 @@ int perf_quiet_option(void)
redirect_to_stderr = 0;
debug_peo_args = 0;
debug_kmaps = 0;
+ debug_type_profile = 0;

return 0;
}
diff --git a/tools/perf/util/debug.h b/tools/perf/util/debug.h
index 35a7a5ae762e..a4026d1fd6a3 100644
--- a/tools/perf/util/debug.h
+++ b/tools/perf/util/debug.h
@@ -14,6 +14,7 @@ extern int debug_peo_args;
extern bool quiet, dump_trace;
extern int debug_ordered_events;
extern int debug_data_convert;
+extern int debug_type_profile;

#ifndef pr_fmt
#define pr_fmt(fmt) fmt
--
2.44.0.291.gc1ea87d7ee-goog