perf annotate-data: Add 'enum type_match_result'

And let check_variable() return the enum value so that callers can know
what was the problem.  This will be used by the later patch to update
the statistics correctly and print the error message in a right place.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240816235840.2754937-4-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/annotate-data.c

@@ -345,9 +345,20 @@ static bool find_cu_die(struct debuginfo *di, u64 pc, Dwarf_Die *cu_die)
 	return false;
 }
 
+enum type_match_result {
+	PERF_TMR_UNKNOWN = 0,
+	PERF_TMR_OK,
+	PERF_TMR_NO_TYPE,
+	PERF_TMR_NO_POINTER,
+	PERF_TMR_NO_SIZE,
+	PERF_TMR_BAD_OFFSET,
+};
+
 /* The type info will be saved in @type_die */
-static int check_variable(struct data_loc_info *dloc, Dwarf_Die *var_die,
-			  Dwarf_Die *type_die, int reg, int offset, bool is_fbreg)
+static enum type_match_result check_variable(struct data_loc_info *dloc,
+					     Dwarf_Die *var_die,
+					     Dwarf_Die *type_die, int reg,
+					     int offset, bool is_fbreg)
 {
 	Dwarf_Word size;
 	bool is_pointer = true;
@@ -364,7 +375,7 @@ static int check_variable(struct data_loc_info *dloc, Dwarf_Die *var_die,
 	if (__die_get_real_type(var_die, type_die) == NULL) {
 		pr_debug_dtp("variable has no type\n");
 		ann_data_stat.no_typeinfo++;
-		return -1;
+		return PERF_TMR_NO_TYPE;
 	}
 
 	/*
@@ -378,7 +389,7 @@ static int check_variable(struct data_loc_info *dloc, Dwarf_Die *var_die,
 		    __die_get_real_type(type_die, type_die) == NULL) {
 			pr_debug_dtp("no pointer or no type\n");
 			ann_data_stat.no_typeinfo++;
-			return -1;
+			return PERF_TMR_NO_POINTER;
 		}
 	}
 
@@ -391,7 +402,7 @@ static int check_variable(struct data_loc_info *dloc, Dwarf_Die *var_die,
 	if (dwarf_aggregate_size(&sized_type, &size) < 0) {
 		pr_debug_dtp("type size is unknown\n");
 		ann_data_stat.invalid_size++;
-		return -1;
+		return PERF_TMR_NO_SIZE;
 	}
 
 	/* Minimal sanity check */
@@ -399,10 +410,10 @@ static int check_variable(struct data_loc_info *dloc, Dwarf_Die *var_die,
 		pr_debug_dtp("offset: %d is bigger than size: %"PRIu64"\n",
 			     offset, size);
 		ann_data_stat.bad_offset++;
-		return -1;
+		return PERF_TMR_BAD_OFFSET;
 	}
 
-	return 0;
+	return PERF_TMR_OK;
 }
 
 struct type_state_stack *find_stack_state(struct type_state *state,
@@ -652,7 +663,7 @@ bool get_global_var_type(Dwarf_Die *cu_die, struct data_loc_info *dloc,
 	/* Try to get the variable by address first */
 	if (die_find_variable_by_addr(cu_die, var_addr, &var_die, &offset) &&
 	    check_variable(dloc, &var_die, type_die, DWARF_REG_PC, offset,
-			   /*is_fbreg=*/false) == 0) {
+			   /*is_fbreg=*/false) == PERF_TMR_OK) {
 		var_name = dwarf_diename(&var_die);
 		*var_offset = offset;
 		goto ok;
@@ -666,7 +677,7 @@ bool get_global_var_type(Dwarf_Die *cu_die, struct data_loc_info *dloc,
 	/* Try to get the name of global variable */
 	if (die_find_variable_at(cu_die, var_name, pc, &var_die) &&
 	    check_variable(dloc, &var_die, type_die, DWARF_REG_PC, *var_offset,
-			   /*is_fbreg=*/false) == 0)
+			   /*is_fbreg=*/false) == PERF_TMR_OK)
 		goto ok;
 
 	return false;
@@ -1205,6 +1216,7 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
 	bool is_fbreg = false;
 	u64 pc;
 	char buf[64];
+	enum type_match_result result;
 
 	if (dloc->op->multi_regs)
 		snprintf(buf, sizeof(buf), "reg%d, reg%d", dloc->op->reg1, dloc->op->reg2);
@@ -1299,8 +1311,8 @@ 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(dloc, &var_die, type_die, reg, offset, is_fbreg);
-		if (ret == 0) {
+		result = check_variable(dloc, &var_die, type_die, reg, offset, is_fbreg);
+		if (result == PERF_TMR_OK) {
 			pr_debug_dtp("found \"%s\" in scope=%d/%d (die: %#lx) ",
 				     dwarf_diename(&var_die), i+1, nr_scopes,
 				     (long)dwarf_dieoffset(&scopes[i]));
@@ -1315,12 +1327,14 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
 			}
 			pr_debug_location(&var_die, pc, reg);
 			pr_debug_type_name(type_die, TSR_KIND_TYPE);
+			ret = 0;
 		} else {
 			pr_debug_dtp("check variable \"%s\" failed (die: %#lx)\n",
 				     dwarf_diename(&var_die),
 				     (long)dwarf_dieoffset(&var_die));
 			pr_debug_location(&var_die, pc, reg);
 			pr_debug_type_name(type_die, TSR_KIND_TYPE);
+			ret = -1;
 		}
 		dloc->type_offset = offset;
 		goto out;