From: Namhyung Kim <namhyung@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>,
Jiri Olsa <jolsa@kernel.org>,
Peter Zijlstra <peterz@infradead.org>
Cc: Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
Ingo Molnar <mingo@kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-perf-users@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Stephane Eranian <eranian@google.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Andi Kleen <ak@linux.intel.com>,
linux-trace-devel@vger.kernel.org,
linux-toolchains@vger.kernel.org
Subject: [PATCH 52/52] perf annotate-data: Add debug message
Date: Thu, 9 Nov 2023 16:00:11 -0800 [thread overview]
Message-ID: <20231110000012.3538610-53-namhyung@kernel.org> (raw)
In-Reply-To: <20231110000012.3538610-1-namhyung@kernel.org>
This is just for debugging and not for merge.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
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 416c0b5649fc..8e318349f430 100644
--- a/tools/perf/util/annotate-data.c
+++ b/tools/perf/util/annotate-data.c
@@ -90,6 +90,21 @@ 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_from_type(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
@@ -376,7 +391,7 @@ 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;
@@ -397,14 +412,20 @@ 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);
}
}
}
@@ -484,6 +505,8 @@ 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;
}
@@ -492,8 +515,10 @@ 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;
@@ -508,10 +533,14 @@ 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;
@@ -531,6 +560,8 @@ 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;
@@ -561,8 +592,13 @@ 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) {
@@ -575,6 +611,8 @@ 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;
}
@@ -584,6 +622,8 @@ 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 &&
@@ -623,6 +663,8 @@ 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
@@ -726,6 +768,9 @@ 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;
}
@@ -739,6 +784,10 @@ 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;
}
@@ -760,6 +809,11 @@ 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;
}
@@ -783,12 +837,13 @@ 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, ¬es->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,
@@ -821,6 +876,16 @@ 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;
@@ -829,12 +894,16 @@ 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 */
@@ -870,6 +939,18 @@ 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
@@ -888,11 +969,15 @@ 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;
}
@@ -901,6 +986,8 @@ 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;
}
@@ -953,6 +1040,21 @@ 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;
}
@@ -969,8 +1071,10 @@ 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,
--
2.42.0.869.gea05f2083d-goog
next prev parent reply other threads:[~2023-11-10 0:04 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-09 23:59 [RFC 00/52] perf tools: Introduce data type profiling (v2) Namhyung Kim
2023-11-09 23:59 ` [PATCH 01/52] perf annotate: Pass "-l" option to objdump conditionally Namhyung Kim
2023-11-09 23:59 ` [PATCH 02/52] perf annotate: Move raw_comment and raw_func_start Namhyung Kim
2023-11-09 23:59 ` [PATCH 03/52] perf tools: Add util/debuginfo.[ch] files Namhyung Kim
2023-11-09 23:59 ` [PATCH 04/52] perf dwarf-aux: Fix die_get_typename() for void * Namhyung Kim
2023-11-09 23:59 ` [PATCH 05/52] perf dwarf-aux: Move #ifdef code to the header file Namhyung Kim
2023-11-09 23:59 ` [PATCH 06/52] perf dwarf-aux: Add die_get_scopes() helper Namhyung Kim
2023-11-09 23:59 ` [PATCH 07/52] perf dwarf-aux: Add die_find_variable_by_reg() helper Namhyung Kim
2023-11-09 23:59 ` [PATCH 08/52] perf build: Add feature check for dwarf_getcfi() Namhyung Kim
2023-11-10 10:26 ` Masami Hiramatsu
2023-11-09 23:59 ` [PATCH 09/52] perf probe: Convert to check dwarf_getcfi feature Namhyung Kim
2023-11-10 10:25 ` Masami Hiramatsu
2023-11-09 23:59 ` [PATCH 10/52] perf dwarf-aux: Factor out die_get_typename_from_type() Namhyung Kim
2023-11-09 23:59 ` [PATCH 11/52] perf dwarf-regs: Add get_dwarf_regnum() Namhyung Kim
2023-11-09 23:59 ` [PATCH 12/52] perf annotate-data: Add find_data_type() Namhyung Kim
[not found] ` <CA+JHD90fkWNrQWO5DrHeV8mCmFyKKqJ8fV=KwztRi7TSw+8yDg@mail.gmail.com>
2023-11-20 20:43 ` Namhyung Kim
2023-11-09 23:59 ` [PATCH 13/52] perf annotate-data: Add dso->data_types tree Namhyung Kim
2023-12-21 20:10 ` Arnaldo Carvalho de Melo
2023-12-21 20:13 ` Arnaldo Carvalho de Melo
2023-12-21 20:32 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 14/52] perf annotate: Factor out evsel__get_arch() Namhyung Kim
2023-12-23 14:14 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 15/52] perf annotate: Check if operand has multiple regs Namhyung Kim
2023-11-09 23:59 ` [PATCH 16/52] perf annotate: Add annotate_get_insn_location() Namhyung Kim
2023-11-09 23:59 ` [PATCH 17/52] perf annotate: Implement hist_entry__get_data_type() Namhyung Kim
2023-11-09 23:59 ` [PATCH 18/52] perf report: Add 'type' sort key Namhyung Kim
2023-11-21 17:55 ` Arnaldo Carvalho de Melo
2023-11-22 18:49 ` Namhyung Kim
2023-11-22 19:54 ` Arnaldo Carvalho de Melo
2023-11-22 21:13 ` Namhyung Kim
2023-11-23 13:40 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 19/52] perf report: Support data type profiling Namhyung Kim
2023-11-09 23:59 ` [PATCH 20/52] perf annotate-data: Add member field in the data type Namhyung Kim
2023-11-09 23:59 ` [PATCH 21/52] perf annotate-data: Update sample histogram for type Namhyung Kim
2023-11-09 23:59 ` [PATCH 22/52] perf report: Add 'typeoff' sort key Namhyung Kim
2023-11-09 23:59 ` [PATCH 23/52] perf report: Add 'symoff' " Namhyung Kim
2023-12-23 14:29 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 24/52] perf annotate: Add --data-type option Namhyung Kim
2023-11-09 23:59 ` [PATCH 25/52] perf annotate: Support event group display Namhyung Kim
2023-11-09 23:59 ` [PATCH 26/52] perf annotate: Add --type-stat option for debugging Namhyung Kim
2023-11-09 23:59 ` [PATCH 27/52] perf annotate: Add --insn-stat " Namhyung Kim
2023-11-09 23:59 ` [PATCH 28/52] perf annotate-data: Parse 'lock' prefix from llvm-objdump Namhyung Kim
2023-11-09 23:59 ` [PATCH 29/52] perf annotate-data: Handle macro fusion on x86 Namhyung Kim
2023-11-09 23:59 ` [PATCH 30/52] perf annotate-data: Handle array style accesses Namhyung Kim
2023-11-09 23:59 ` [PATCH 31/52] perf annotate-data: Add stack operation pseudo type Namhyung Kim
2023-11-09 23:59 ` [PATCH 32/52] perf dwarf-aux: Add die_find_variable_by_addr() Namhyung Kim
2023-11-27 22:07 ` Arnaldo Carvalho de Melo
2023-11-09 23:59 ` [PATCH 33/52] perf annotate-data: Handle PC-relative addressing Namhyung Kim
2023-11-09 23:59 ` [PATCH 34/52] perf annotate-data: Support global variables Namhyung Kim
2023-11-09 23:59 ` [PATCH 35/52] perf dwarf-aux: Add die_get_cfa() Namhyung Kim
2023-11-09 23:59 ` [PATCH 36/52] perf annotate-data: Support stack variables Namhyung Kim
2023-11-09 23:59 ` [PATCH 37/52] perf dwarf-aux: Check allowed DWARF Ops Namhyung Kim
2023-11-09 23:59 ` [PATCH 38/52] perf dwarf-aux: Add die_collect_vars() Namhyung Kim
2023-11-09 23:59 ` [PATCH 39/52] perf dwarf-aux: Handle type transfer for memory access Namhyung Kim
2023-11-09 23:59 ` [PATCH 40/52] perf annotate-data: Introduce struct data_loc_info Namhyung Kim
2023-11-10 0:00 ` [PATCH 41/52] perf map: Add map__objdump_2rip() Namhyung Kim
2023-11-10 0:00 ` [PATCH 42/52] perf annotate: Add annotate_get_basic_blocks() Namhyung Kim
2023-11-10 0:00 ` [PATCH 43/52] perf annotate-data: Maintain variable type info Namhyung Kim
2023-11-10 0:00 ` [PATCH 44/52] perf annotate-data: Add update_insn_state() Namhyung Kim
2023-11-10 0:00 ` [PATCH 45/52] perf annotate-data: Handle global variable access Namhyung Kim
2023-11-10 0:00 ` [PATCH 46/52] perf annotate-data: Handle call instructions Namhyung Kim
2023-11-10 0:00 ` [PATCH 47/52] perf annotate-data: Implement instruction tracking Namhyung Kim
2023-11-10 0:00 ` [PATCH 48/52] perf annotate: Parse x86 segment register location Namhyung Kim
2023-11-10 0:00 ` [PATCH 49/52] perf annotate-data: Handle this-cpu variables in kernel Namhyung Kim
2023-11-10 0:00 ` [PATCH 50/52] perf annotate-data: Track instructions with a this-cpu variable Namhyung Kim
2023-11-10 0:00 ` [PATCH 51/52] perf annotate-data: Add stack canary type Namhyung Kim
2023-11-10 0:00 ` Namhyung Kim [this message]
2023-11-10 12:05 ` [RFC 00/52] perf tools: Introduce data type profiling (v2) Arnaldo Carvalho de Melo
2023-11-11 2:27 ` Namhyung Kim
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