[PATCH AUTOSEL 4.18 11/65] perf annotate: Properly interpret indirect call

From: Sasha Levin
Date: Sun Sep 30 2018 - 20:53:17 EST


From: Martin LiÅka <mliska@xxxxxxx>

[ Upstream commit 1dc27f63303db58ce1b1a6932d1825305f86d574 ]

The patch changes the parsing of:

callq *0x8(%rbx)

from:

0.26 â â callq *8

to:

0.26 â â callq *0x8(%rbx)

in this case an address is followed by a register, thus one can't parse
only the address.

Committer testing:

1) run 'perf record sleep 10'
2) before applying the patch, run:

perf annotate --stdio2 > /tmp/before

3) after applying the patch, run:

perf annotate --stdio2 > /tmp/after

4) diff /tmp/before /tmp/after:
--- /tmp/before 2018-08-28 11:16:03.238384143 -0300
+++ /tmp/after 2018-08-28 11:15:39.335341042 -0300
@@ -13274,7 +13274,7 @@
â jle 128
hash_value = hash_table->hash_func (key);
mov 0x8(%rsp),%rdi
- 0.91 â callq *30
+ 0.91 â callq *0x30(%r12)
mov $0x2,%r8d
cmp $0x2,%eax
node_hash = hash_table->hashes[node_index];
@@ -13848,7 +13848,7 @@
mov %r14,%rdi
sub %rbx,%r13
mov %r13,%rdx
- â callq *38
+ â callq *0x38(%r15)
cmp %rax,%r13
1.91 â je 240
1b4: mov $0xffffffff,%r13d
@@ -14026,7 +14026,7 @@
mov %rcx,-0x500(%rbp)
mov %r15,%rsi
mov %r14,%rdi
- â callq *38
+ â callq *0x38(%rax)
mov -0x500(%rbp),%rcx
cmp %rax,%rcx
â jne 9b0
<SNIP tons of other such cases>

Signed-off-by: Martin LiÅka <mliska@xxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Tested-by: Kim Phillips <kim.phillips@xxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/bd1f3932-be2b-85f9-7582-111ee0a43b07@xxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
tools/perf/util/annotate.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index f91775b4bc3c..31a1e18c7bf2 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -245,8 +245,14 @@ static int call__parse(struct arch *arch, struct ins_operands *ops, struct map_s

indirect_call:
tok = strchr(endptr, '*');
- if (tok != NULL)
- ops->target.addr = strtoull(tok + 1, NULL, 16);
+ if (tok != NULL) {
+ endptr++;
+
+ /* Indirect call can use a non-rip register and offset: callq *0x8(%rbx).
+ * Do not parse such instruction. */
+ if (strstr(endptr, "(%r") == NULL)
+ ops->target.addr = strtoull(endptr, NULL, 16);
+ }
goto find_target;
}

--
2.17.1