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

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>

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 6a274e27b1087dbf734befdd3a3875049f63f60c..a711bedace475953cf74bc11526e6c5aa513367d 100644 (file)
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -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);

diff --git a/tools/perf/util/print_insn.c b/tools/perf/util/print_insn.c
index 459e0e93d7b1b2f000c6f2569eecd553da5576e6..32dc9dad9cf2950764be861b614612137c3b8161 100644 (file)
--- a/tools/perf/util/print_insn.c
+++ b/tools/perf/util/print_insn.c
@@ -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;
 }

diff --git a/tools/perf/util/print_insn.h b/tools/perf/util/print_insn.h
index 465bdcfcc2fd6efd0cd87d4c2530fb6e33292e7a..6447dd41b5437a3a6c99b3a910f85f16f89cc11c 100644 (file)
--- a/tools/perf/util/print_insn.h
+++ b/tools/perf/util/print_insn.h
@@ -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 */