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* [PATCH 1/2] perf, capstone: Support 32bit code under 64bit OS
@ 2024-02-27 23:48 Andi Kleen
  2024-02-27 23:48 ` [PATCH 2/2] perf, capstone: Support capstone for -F +brstackinsn Andi Kleen
                   ` (2 more replies)
  0 siblings, 3 replies; 9+ messages in thread
From: Andi Kleen @ 2024-02-27 23:48 UTC (permalink / raw)
  To: linux-perf-users; +Cc: changbin.du, adrian.hunter, Andi Kleen

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

Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 tools/perf/util/print_insn.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/print_insn.c b/tools/perf/util/print_insn.c
index 459e0e93d7b1..bd7a95e64ce5 100644
--- 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")) {
@@ -101,9 +103,21 @@ size_t sample__fprintf_insn_asm(struct perf_sample *sample, struct thread *threa
 	size_t count;
 	size_t printed = 0;
 	int ret;
+	struct addr_location al;
+	bool is64bit = machine__is(machine, "x86_64");
+	struct dso *dso;
+
+	addr_location__init(&al);
+	if (thread__find_map(thread, sample->cpumode, sample->ip, &al) &&
+		(dso = map__dso(al.map)) != NULL &&
+		(dso->data.status != DSO_DATA_STATUS_ERROR)) {
+		map__load(al.map);
+		is64bit = dso->is_64_bit;
+	}
+	addr_location__exit(&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);
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2024-02-29  7:02 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-02-27 23:48 [PATCH 1/2] perf, capstone: Support 32bit code under 64bit OS Andi Kleen
2024-02-27 23:48 ` [PATCH 2/2] perf, capstone: Support capstone for -F +brstackinsn Andi Kleen
2024-02-28 11:05   ` Changbin Du
2024-02-28 23:26     ` Andi Kleen
2024-02-28 11:00 ` [PATCH 1/2] perf, capstone: Support 32bit code under 64bit OS Changbin Du
2024-02-28 23:29   ` Andi Kleen
2024-02-28 11:42 ` Adrian Hunter
2024-02-28 23:30   ` Andi Kleen
2024-02-29  7:02     ` Adrian Hunter

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