perf annotate-data: Update debug messages

In check_matching_type(), it'd be easier to display the typename in
question if it's available.

For example, check out the line starts with 'chk'.
  -----------------------------------------------------------
  find data type for 0x10(reg0) at cpuacct_charge+0x13
  CU for kernel/sched/build_utility.c (die:0x137ee0b)
  frame base: cfa=1 fbreg=7
  scope: [3/3] (die:13d9632)
  bb: [c - 13]
  var [c] reg5 type='struct task_struct*' size=0x8 (die:0x1381230)
  mov [c] 0xdf8(reg5) -> reg0 type='struct css_set*' size=0x8 (die:0x1385c56)
  chk [13] reg0 offset=0x10 ok=1 kind=1 (struct css_set*) : Good!         <<<--- here
  found by insn track: 0x10(reg0) type-offset=0x10
  final result:  type='struct css_set' size=0x250 (die:0x1385b0e)

Another example:
  -----------------------------------------------------------
  find data type for 0x8(reg0) at menu_select+0x279
  CU for drivers/cpuidle/governors/menu.c (die:0x7b0fe79)
  frame base: cfa=1 fbreg=7
  scope: [2/2] (die:7b11010)
  bb: [273 - 277]
  bb: [279 - 279]
  chk [279] reg0 offset=0x8 ok=0 kind=0 cfa : no type information
  scope: [1/2] (die:7b10cbc)
  bb: [0 - 64]
  ...
  mov [26a] imm=0xffffffff -> reg15
  bb: [273 - 277]
  bb: [279 - 279]
  chk [279] reg0 offset=0x8 ok=1 kind=1 (long long unsigned int) : no/void pointer    <<<--- here
  final result: no/void pointer

Also change some places to print negative offsets properly.

Before:
  -----------------------------------------------------------
  find data type for 0xffffff40(reg6) at __tcp_transmit_skb+0x58

After:
  -----------------------------------------------------------
  find data type for -0xc0(reg6) at __tcp_transmit_skb+0x58

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/20240821232628.353177-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c
index 1e8328dde72070a23733773f521d2c0d30a77018..7d4b5aaa3b6a4e13c8052f5d70f658f3d22627ef 100644 (file)
--- a/tools/perf/util/annotate-data.c
+++ b/tools/perf/util/annotate-data.c
@@ -960,9 +960,16 @@ static enum type_match_result check_matching_type(struct type_state *state,
        Dwarf_Word size;
        u32 insn_offset = dloc->ip - dloc->ms->sym->start;
        int reg = dloc->op->reg1;
+       int offset = dloc->op->offset;
+       const char *offset_sign = "";
 
-       pr_debug_dtp("chk [%x] reg%d offset=%#x ok=%d kind=%d ",
-                    insn_offset, reg, dloc->op->offset,
+       if (offset < 0) {
+               offset = -offset;
+               offset_sign = "-";
+       }
+
+       pr_debug_dtp("chk [%x] reg%d offset=%s%#x ok=%d kind=%d ",
+                    insn_offset, reg, offset_sign, offset,
                     state->regs[reg].ok, state->regs[reg].kind);
 
        if (!state->regs[reg].ok)
@@ -970,6 +977,12 @@ static enum type_match_result check_matching_type(struct type_state *state,
 
        if (state->regs[reg].kind == TSR_KIND_TYPE) {
                Dwarf_Die sized_type;
+               struct strbuf sb;
+
+               strbuf_init(&sb, 32);
+               die_get_typename_from_type(&state->regs[reg].type, &sb);
+               pr_debug_dtp("(%s)", sb.buf);
+               strbuf_release(&sb);
 
                /*
                 * Normal registers should hold a pointer (or array) to
@@ -1119,7 +1132,6 @@ check_non_register:
 check_kernel:
        if (dso__kernel(map__dso(dloc->ms->map))) {
                u64 addr;
-               int offset;
 
                /* Direct this-cpu access like "%gs:0x34740" */
                if (dloc->op->segment == INSN_SEG_X86_GS && dloc->op->imm &&
@@ -1271,6 +1283,13 @@ again:
                                            cu_die, type_die);
                if (ret == PERF_TMR_OK) {
                        char buf[64];
+                       int offset = dloc->op->offset;
+                       const char *offset_sign = "";
+
+                       if (offset < 0) {
+                               offset = -offset;
+                               offset_sign = "-";
+                       }
 
                        if (dloc->op->multi_regs)
                                snprintf(buf, sizeof(buf), "reg%d, reg%d",
@@ -1278,8 +1297,8 @@ again:
                        else
                                snprintf(buf, sizeof(buf), "reg%d", dloc->op->reg1);
 
-                       pr_debug_dtp("found by insn track: %#x(%s) type-offset=%#x\n",
-                                    dloc->op->offset, buf, dloc->type_offset);
+                       pr_debug_dtp("found by insn track: %s%#x(%s) type-offset=%#x\n",
+                                    offset_sign, offset, buf, dloc->type_offset);
                        break;
                }
 
@@ -1302,7 +1321,7 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
        struct annotated_op_loc *loc = dloc->op;
        Dwarf_Die cu_die, var_die;
        Dwarf_Die *scopes = NULL;
-       int reg, offset;
+       int reg, offset = loc->offset;
        int ret = -1;
        int i, nr_scopes;
        int fbreg = -1;
@@ -1312,6 +1331,7 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
        u64 pc;
        char buf[64];
        enum type_match_result result = PERF_TMR_UNKNOWN;
+       const char *offset_sign = "";
 
        if (dloc->op->multi_regs)
                snprintf(buf, sizeof(buf), "reg%d, reg%d", dloc->op->reg1, dloc->op->reg2);
@@ -1320,10 +1340,15 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
        else
                snprintf(buf, sizeof(buf), "reg%d", dloc->op->reg1);
 
+       if (offset < 0) {
+               offset = -offset;
+               offset_sign = "-";
+       }
+
        pr_debug_dtp("-----------------------------------------------------------\n");
-       pr_debug_dtp("find data type for %#x(%s) at %s+%#"PRIx64"\n",
-                    dloc->op->offset, buf, dloc->ms->sym->name,
-                    dloc->ip - dloc->ms->sym->start);
+       pr_debug_dtp("find data type for %s%#x(%s) at %s+%#"PRIx64"\n",
+                    offset_sign, offset, buf,
+                    dloc->ms->sym->name, dloc->ip - dloc->ms->sym->start);
 
        /*
         * IP is a relative instruction address from the start of the map, as
@@ -1453,8 +1478,8 @@ retry:
        }
 
 out:
+       pr_debug_dtp("final result: ");
        if (found) {
-               pr_debug_dtp("final type:");
                pr_debug_type_name(type_die, TSR_KIND_TYPE);
                ret = 0;
        } else {