[PATCH 48/48] perf annotate-data: Add debug message

From: Namhyung Kim
Date: Wed Oct 11 2023 - 23:56:01 EST

This is just for debugging and not for merge.

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/annotate-data.c | 122 +++++++++++++++++++++++++++++---
tools/perf/util/annotate-data.h | 2 +-
2 files changed, 114 insertions(+), 10 deletions(-)

diff --git a/tools/perf/util/annotate-data.c b/tools/perf/util/annotate-data.c
index 68d7d207e2f7..bb0ad26e704d 100644
--- a/tools/perf/util/annotate-data.c
+++ b/tools/perf/util/annotate-data.c
@@ -115,6 +115,21 @@ void exit_type_state(struct type_state *state)
}
}

+static void debug_print_type_name(Dwarf_Die *die)
+{
+ struct strbuf sb;
+ char *str;
+
+ if (!verbose)
+ return;
+
+ strbuf_init(&sb, 32);
+ __die_get_typename(die, &sb);
+ str = strbuf_detach(&sb, NULL);
+ pr_debug("%s (die:%lx)\n", str, 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
@@ -401,7 +416,7 @@ static struct type_state_stack *findnew_stack_state(struct type_state *state,
* is used only at the given location and updates an entry in the table.
*/
void update_var_state(struct type_state *state, struct data_loc_info *dloc,
- u64 addr, struct die_var_type *var_types)
+ u64 addr, u64 off, struct die_var_type *var_types)
{
Dwarf_Die mem_die;
struct die_var_type *var;
@@ -422,14 +437,20 @@ void update_var_state(struct type_state *state, struct data_loc_info *dloc,

if (var->reg == DWARF_REG_FB) {
findnew_stack_state(state, var->offset, &mem_die);
+ pr_debug("var [%lx] stack fbreg (%x, %d) type=", off, var->offset, var->offset);
+ debug_print_type_name(&mem_die);
} else if (var->reg == fbreg) {
findnew_stack_state(state, var->offset - fb_offset, &mem_die);
+ pr_debug("var [%lx] stack cfa (%x, %d) fb-offset=%d type=", off, var->offset - fb_offset, var->offset - fb_offset, fb_offset);
+ debug_print_type_name(&mem_die);
} else if (has_reg_type(state, var->reg) && var->offset == 0) {
struct type_state_reg *reg;

reg = &state->regs[var->reg];
reg->type = mem_die;
reg->ok = true;
+ pr_debug("var [%lx] reg%d type=", off, var->reg);
+ debug_print_type_name(&mem_die);
}
}
}
@@ -509,6 +530,8 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
die_get_real_type(&func_die, &type_die)) {
state->regs[state->ret_reg].type = type_die;
state->regs[state->ret_reg].ok = true;
+ pr_debug("fun [%lx] reg0 return from %s type=", dl->al.offset, dwarf_diename(&func_die));
+ debug_print_type_name(&type_die);
}
return;
}
@@ -517,8 +540,10 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
if (!strstr(dl->ins.name, "mov"))
return;

- if (annotate_get_insn_location(dloc->arch, dl, &loc) < 0)
+ if (annotate_get_insn_location(dloc->arch, dl, &loc) < 0) {
+ pr_debug("failed to get mov insn loc\n");
return;
+ }

if (dloc->fb_cfa) {
u64 ip = dloc->ms->sym->start + dl->al.offset;
@@ -533,10 +558,14 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
if (!has_reg_type(state, dst->reg1))
return;

- if (has_reg_type(state, src->reg1))
+ if (has_reg_type(state, src->reg1)) {
state->regs[dst->reg1] = state->regs[src->reg1];
- else if (dloc->ms->map->dso->kernel &&
- src->segment == INSN_SEG_X86_GS) {
+ if (state->regs[dst->reg1].ok) {
+ pr_debug("mov [%lx] reg%d -> reg%d type=", dl->al.offset, src->reg1, dst->reg1);
+ debug_print_type_name(&state->regs[dst->reg1].type);
+ }
+ } else if (dloc->ms->map->dso->kernel &&
+ src->segment == INSN_SEG_X86_GS) {
struct map_symbol *ms = dloc->ms;
int offset = src->offset;
u64 ip = ms->sym->start + dl->al.offset;
@@ -556,6 +585,8 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
var_name, offset, &type_die)) {
state->regs[dst->reg1].type = type_die;
state->regs[dst->reg1].ok = true;
+ pr_debug("mov [%lx] percpu -> reg%d type=", dl->al.offset, dst->reg1);
+ debug_print_type_name(&state->regs[dst->reg1].type);
}
} else
state->regs[dst->reg1].ok = false;
@@ -586,8 +617,13 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
var_name, offset, &type_die)) {
state->regs[dst->reg1].type = type_die;
state->regs[dst->reg1].ok = true;
- } else
+ pr_debug("mov [%lx] PC-rel -> reg%d type=", dl->al.offset, dst->reg1);
+ debug_print_type_name(&type_die);
+ } else {
+ if (var_name)
+ pr_debug("??? [%lx] PC-rel (%lx: %s%+d)\n", dl->al.offset, var_addr, var_name, offset);
state->regs[dst->reg1].ok = false;
+ }
}
/* And check stack variables with offset */
else if (sreg == fbreg) {
@@ -600,6 +636,8 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
&type_die)) {
state->regs[dst->reg1].type = type_die;
state->regs[dst->reg1].ok = true;
+ pr_debug("mov [%lx] stack (-%#x, %d) -> reg%d type=", dl->al.offset, -offset, offset, dst->reg1);
+ debug_print_type_name(&type_die);
} else
state->regs[dst->reg1].ok = false;
}
@@ -609,6 +647,8 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
src->offset, &type_die)) {
state->regs[dst->reg1].type = type_die;
state->regs[dst->reg1].ok = true;
+ pr_debug("mov [%lx] %#x(reg%d) -> reg%d type=", dl->al.offset, src->offset, sreg, dst->reg1);
+ debug_print_type_name(&type_die);
}
/* Or try another register if any */
else if (src->multi_regs && sreg == src->reg1 &&
@@ -648,6 +688,8 @@ void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
findnew_stack_state(state, offset,
&state->regs[src->reg1].type);
}
+ pr_debug("mov [%lx] reg%d -> stack (-%#x, %d) type=", dl->al.offset, src->reg1, -offset, offset);
+ debug_print_type_name(&state->regs[src->reg1].type);
}
/*
* Ignore other transfers since it'd set a value in a struct
@@ -751,6 +793,9 @@ static bool find_matching_type(struct type_state *state,
(unsigned)dloc->type_offset >= size)
return false;

+ pr_debug("%s: [%lx] reg=%d offset=%d type=",
+ __func__, dloc->ip - dloc->ms->sym->start, reg, dloc->type_offset);
+ debug_print_type_name(type_die);
return true;
}

@@ -764,6 +809,10 @@ static bool find_matching_type(struct type_state *state,
*type_die = stack->type;
/* Update the type offset from the start of slot */
dloc->type_offset -= stack->offset;
+
+ pr_debug("%s: [%lx] stack offset=%d type=",
+ __func__, dloc->ip - dloc->ms->sym->start, dloc->type_offset);
+ debug_print_type_name(type_die);
return true;
}

@@ -785,6 +834,11 @@ static bool find_matching_type(struct type_state *state,
*type_die = stack->type;
/* Update the type offset from the start of slot */
dloc->type_offset -= fboff + stack->offset;
+
+ pr_debug("%s: [%lx] cfa stack offset=%d type_offset=%d type=",
+ __func__, dloc->ip - dloc->ms->sym->start,
+ dloc->type_offset + stack->offset, dloc->type_offset);
+ debug_print_type_name(type_die);
return true;
}

@@ -808,12 +862,13 @@ static bool find_data_type_insn(struct data_loc_info *dloc, int reg,
list_for_each_entry(bb, basic_blocks, list) {
struct disasm_line *dl = bb->begin;

+ pr_debug("bb: [%lx - %lx]\n", bb->begin->al.offset, bb->end->al.offset);
list_for_each_entry_from(dl, &notes->src->source, al.node) {
u64 this_ip = sym->start + dl->al.offset;
u64 addr = map__rip_2objdump(dloc->ms->map, this_ip);

/* Update variable type at this address */
- update_var_state(&state, dloc, addr, var_types);
+ update_var_state(&state, dloc, addr, dl->al.offset, var_types);

if (this_ip == dloc->ip) {
found = find_matching_type(&state, dloc, reg,
@@ -846,6 +901,16 @@ static int find_data_type_block(struct data_loc_info *dloc, int reg,
u64 src_ip, dst_ip;
int ret = -1;

+ if (dloc->fb_cfa) {
+ u64 pc = map__rip_2objdump(dloc->ms->map, dloc->ip);
+ int fbreg, fboff;
+
+ if (die_get_cfa(dloc->di->dbg, pc, &fbreg, &fboff) < 0)
+ fbreg = -1;
+
+ pr_debug("CFA reg=%d offset=%d\n", fbreg, fboff);
+ }
+
dst_ip = dloc->ip;
for (int i = nr_scopes - 1; i >= 0; i--) {
Dwarf_Addr base, start, end;
@@ -854,12 +919,16 @@ static int find_data_type_block(struct data_loc_info *dloc, int reg,
if (dwarf_ranges(&scopes[i], 0, &base, &start, &end) < 0)
break;

+ pr_debug("scope: [%d/%d] (die:%lx)\n", i + 1, nr_scopes, dwarf_dieoffset(&scopes[i]));
src_ip = map__objdump_2rip(dloc->ms->map, start);

/* Get basic blocks for this scope */
if (annotate_get_basic_blocks(dloc->ms->sym, src_ip, dst_ip,
- &this_blocks) < 0)
+ &this_blocks) < 0) {
+ pr_debug("cannot find a basic block from %lx to %lx\n",
+ src_ip - dloc->ms->sym->start, dst_ip - dloc->ms->sym->start);
continue;
+ }
prepend_basic_blocks(&this_blocks, &basic_blocks);

/* Get variable info for this scope and add to var_types list */
@@ -895,6 +964,18 @@ 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("-----------------------------------------------------------\n");
+ pr_debug("%s [%lx] for reg%d%s in %s\n", __func__, dloc->ip - dloc->ms->sym->start,
+ dloc->op->reg1, buf, dloc->ms->sym->name);

/*
* IP is a relative instruction address from the start of the map, as
@@ -913,11 +994,15 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
reg = loc->reg1;
offset = loc->offset;

+ pr_debug("CU die offset: %lx\n", dwarf_dieoffset(&cu_die));
+
if (reg == DWARF_REG_PC) {
if (die_find_variable_by_addr(&cu_die, pc, dloc->var_addr,
&var_die, &offset)) {
ret = check_variable(&var_die, type_die, offset,
/*is_pointer=*/false);
+ if (ret == 0)
+ pr_debug("found PC-rel by addr=%lx offset=%d\n", dloc->var_addr, offset);
dloc->type_offset = offset;
goto out;
}
@@ -926,6 +1011,8 @@ static int find_data_type_die(struct data_loc_info *dloc, Dwarf_Die *type_die)
die_find_variable_at(&cu_die, dloc->var_name, pc, &var_die)) {
ret = check_variable(&var_die, type_die, dloc->type_offset,
/*is_pointer=*/false);
+ if (ret == 0)
+ pr_debug("found \"%s\" by name offset=%d\n", dloc->var_name, dloc->type_offset);
/* dloc->type_offset was updated by the caller */
goto out;
}
@@ -978,6 +1065,21 @@ 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) {
+#if 0
+ const char *filename;
+ int lineno;
+
+ if (cu_find_lineinfo(&cu_die, pc, &filename, &lineno) < 0) {
+ filename = "unknown";
+ lineno = 0;
+ }
+#endif
+ pr_debug("found \"%s\" in scope=%d/%d reg=%d offset=%#x (%d) loc->offset=%d fb-offset=%d (die:%lx scope:%lx) type=",
+ dwarf_diename(&var_die), i+1, nr_scopes, reg, offset, offset, loc->offset, fb_offset, dwarf_dieoffset(&var_die),
+ dwarf_dieoffset(&scopes[i])/*, filename, lineno*/);
+ debug_print_type_name(type_die);
+ }
dloc->type_offset = offset;
goto out;
}
@@ -994,8 +1096,10 @@ 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("no variable found\n");
ann_data_stat.no_var++;
+ }

out:
free(scopes);
diff --git a/tools/perf/util/annotate-data.h b/tools/perf/util/annotate-data.h
index e293980eb11b..44e0f3770432 100644
--- a/tools/perf/util/annotate-data.h
+++ b/tools/perf/util/annotate-data.h
@@ -166,7 +166,7 @@ void exit_type_state(struct type_state *state);

/* Update type state table using variables */
void update_var_state(struct type_state *state, struct data_loc_info *dloc,
- u64 addr, struct die_var_type *var_types);
+ u64 addr, u64 off, struct die_var_type *var_types);

/* Update type state table for an instruction */
void update_insn_state(struct type_state *state, struct data_loc_info *dloc,
--
2.42.0.655.g421f12c284-goog