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perf script: Support 32bit code under 64bit OS with capstone

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Use the DSO to resolve whether an IP is 32bit or 64bit and use that to
configure capstone to the correct mode. This allows to correctly
disassemble 32bit code under a 64bit OS.

  % cat > loop.c
  volatile int var;
  int main(void)
  {
  	int i;
  	for (i = 0; i < 100000; i++)
  		var++;
  }
  % gcc -m32 -o loop loop.c
  % perf record -e cycles:u ./loop
  % perf script -F +disasm
    loop   82665 1833176.618023:      1 cycles:u:   f7eed500 _start+0x0 (/usr/lib/ld-linux.so.2)   movl %esp, %eax
    loop   82665 1833176.618029:      1 cycles:u:   f7eed500 _start+0x0 (/usr/lib/ld-linux.so.2)   movl %esp, %eax
    loop   82665 1833176.618031:      7 cycles:u:   f7eed500 _start+0x0 (/usr/lib/ld-linux.so.2)   movl %esp, %eax
    loop   82665 1833176.618034:     91 cycles:u:   f7eed500 _start+0x0 (/usr/lib/ld-linux.so.2)   movl %esp, %eax
    loop   82665 1833176.618036:   1242 cycles:u:   f7eed500 _start+0x0 (/usr/lib/ld-linux.so.2)   movl %esp, %eax

Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: https://lore.kernel.org/r/20240401210925.209671-2-ak@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Andi Kleen 2024-04-01 14:08:03 -07:00 committed by Arnaldo Carvalho de Melo
parent c2f3d7dfc7
commit 38ab60132b
3 changed files with 28 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
tools/perf/builtin-script.c
View File

@ -1517,7 +1517,8 @@ void script_fetch_insn(struct perf_sample *sample, struct thread *thread,
static int perf_sample__fprintf_insn(struct perf_sample *sample,
struct perf_event_attr *attr,
struct thread *thread,
struct machine *machine, FILE *fp)
struct machine *machine, FILE *fp,
struct addr_location *al)
{
int printed = 0;
@ -1531,7 +1532,7 @@ static int perf_sample__fprintf_insn(struct perf_sample *sample,
}
if (PRINT_FIELD(DISASM) && sample->insn_len) {
printed += fprintf(fp, "\t\t");
printed += sample__fprintf_insn_asm(sample, thread, machine, fp);
printed += sample__fprintf_insn_asm(sample, thread, machine, fp, al);
}
if (PRINT_FIELD(BRSTACKINSN) || PRINT_FIELD(BRSTACKINSNLEN))
printed += perf_sample__fprintf_brstackinsn(sample, thread, attr, machine, fp);
@ -1606,7 +1607,7 @@ static int perf_sample__fprintf_bts(struct perf_sample *sample,
if (print_srcline_last)
printed += map__fprintf_srcline(al->map, al->addr, "\n ", fp);
printed += perf_sample__fprintf_insn(sample, attr, thread, machine, fp);
printed += perf_sample__fprintf_insn(sample, attr, thread, machine, fp, al);
printed += fprintf(fp, "\n");
if (PRINT_FIELD(SRCCODE)) {
int ret = map__fprintf_srccode(al->map, al->addr, stdout,
@ -2259,7 +2260,7 @@ static void process_event(struct perf_script *script,
if (evsel__is_bpf_output(evsel) && PRINT_FIELD(BPF_OUTPUT))
perf_sample__fprintf_bpf_output(sample, fp);
perf_sample__fprintf_insn(sample, attr, thread, machine, fp);
perf_sample__fprintf_insn(sample, attr, thread, machine, fp, al);
if (PRINT_FIELD(PHYS_ADDR))
fprintf(fp, "%16" PRIx64, sample->phys_addr);

27
tools/perf/util/print_insn.c
View File

@ -12,6 +12,8 @@
#include "machine.h"
#include "thread.h"
#include "print_insn.h"
#include "map.h"
#include "dso.h"
size_t sample__fprintf_insn_raw(struct perf_sample *sample, FILE *fp)
{
@ -28,12 +30,12 @@ size_t sample__fprintf_insn_raw(struct perf_sample *sample, FILE *fp)
#ifdef HAVE_LIBCAPSTONE_SUPPORT
#include <capstone/capstone.h>
static int capstone_init(struct machine *machine, csh *cs_handle)
static int capstone_init(struct machine *machine, csh *cs_handle, bool is64)
{
cs_arch arch;
cs_mode mode;
if (machine__is(machine, "x86_64")) {
if (machine__is(machine, "x86_64") && is64) {
arch = CS_ARCH_X86;
mode = CS_MODE_64;
} else if (machine__normalized_is(machine, "x86")) {
@ -93,17 +95,31 @@ static size_t print_insn_x86(struct perf_sample *sample, struct thread *thread,
return printed;
}
static bool is64bitip(struct machine *machine, struct addr_location *al)
{
const struct dso *dso = al->map ? map__dso(al->map) : NULL;
if (dso)
return dso->is_64_bit;
return machine__is(machine, "x86_64") ||
machine__normalized_is(machine, "arm64") ||
machine__normalized_is(machine, "s390");
}
size_t sample__fprintf_insn_asm(struct perf_sample *sample, struct thread *thread,
struct machine *machine, FILE *fp)
struct machine *machine, FILE *fp,
struct addr_location *al)
{
csh cs_handle;
cs_insn *insn;
size_t count;
size_t printed = 0;
int ret;
bool is64bit = is64bitip(machine, al);
/* TODO: Try to initiate capstone only once but need a proper place. */
ret = capstone_init(machine, &cs_handle);
ret = capstone_init(machine, &cs_handle, is64bit);
if (ret < 0) {
/* fallback */
return sample__fprintf_insn_raw(sample, fp);
@ -128,7 +144,8 @@ size_t sample__fprintf_insn_asm(struct perf_sample *sample, struct thread *threa
size_t sample__fprintf_insn_asm(struct perf_sample *sample __maybe_unused,
struct thread *thread __maybe_unused,
struct machine *machine __maybe_unused,
FILE *fp __maybe_unused)
FILE *fp __maybe_unused,
struct addr_location *al __maybe_unused)
{
return 0;
}

2
tools/perf/util/print_insn.h
View File

@ -10,7 +10,7 @@ struct thread;
struct machine;
size_t sample__fprintf_insn_asm(struct perf_sample *sample, struct thread *thread,
struct machine *machine, FILE *fp);
struct machine *machine, FILE *fp, struct addr_location *al);
size_t sample__fprintf_insn_raw(struct perf_sample *sample, FILE *fp);
#endif /* PERF_PRINT_INSN_H */