[PATCH 41/44] perf annotate: Add "_local" to jump/offset validation routines

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Because they all really check if we can access data structures/visual
constructs where a "jump" instruction targets code in the same function,
i.e. things like:

  __pthread_mutex_lock  /usr/lib64/libpthread-2.26.so
  1.95 â       mov    __pthread_force_elision,%ecx
       â    âââtest   %ecx,%ecx
  0.07 â    âââje     60
       â    â  test   $0x300,%esi
       â    ââ jne    60
       â    â  or     $0x100,%esi
       â    â  mov    %esi,0x10(%rdi)
       â 42:â  mov    %esi,%edx
       â    â  lea    0x16(%r8),%rsi
       â    â  mov    %r8,%rdi
       â    â  and    $0x80,%edx
       â    â  add    $0x8,%rsp
       â    ââ jmpq   __lll_lock_elision
       â    â  nop
  0.29 â 60:âââand    $0x80,%esi
  0.07 â       mov    $0x1,%edi
  0.29 â       xor    %eax,%eax
  2.53 â       lock   cmpxchg %edi,(%r8)

And not things like that "jmpq __lll_lock_elision", that instead should behave
like a "call" instruction and "jump" to the disassembly of "___lll_lock_elision".

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-3cwx39u3h66dfw9xjrlt7ca2@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/ui/browsers/annotate.c |  2 +-
 tools/perf/util/annotate.c        |  9 ++++-----
 tools/perf/util/annotate.h        | 14 +++++++++++---
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c
index 3834b264ba41..d77896a99570 100644
--- a/tools/perf/ui/browsers/annotate.c
+++ b/tools/perf/ui/browsers/annotate.c
@@ -155,7 +155,7 @@ static void annotate_browser__draw_current_jump(struct ui_browser *browser)
 	if (strstr(sym->name, "@plt"))
 		return;
 
-	if (!disasm_line__is_valid_jump(cursor, sym))
+	if (!disasm_line__is_valid_local_jump(cursor, sym))
 		return;
 
 	/*
diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index c299881c640a..9524f322f597 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1409,7 +1409,7 @@ static int symbol__parse_objdump_line(struct symbol *sym, FILE *file,
 	if (dl == NULL)
 		return -1;
 
-	if (!disasm_line__has_offset(dl)) {
+	if (!disasm_line__has_local_offset(dl)) {
 		dl->ops.target.offset = dl->ops.target.addr -
 					map__rip_2objdump(map, sym->start);
 		dl->ops.target.offset_avail = true;
@@ -2176,11 +2176,10 @@ size_t disasm__fprintf(struct list_head *head, FILE *fp)
 	return printed;
 }
 
-
-bool disasm_line__is_valid_jump(struct disasm_line *dl, struct symbol *sym)
+bool disasm_line__is_valid_local_jump(struct disasm_line *dl, struct symbol *sym)
 {
 	if (!dl || !dl->ins.ops || !ins__is_jump(&dl->ins) ||
-	    !disasm_line__has_offset(dl) || dl->ops.target.offset < 0 ||
+	    !disasm_line__has_local_offset(dl) || dl->ops.target.offset < 0 ||
 	    dl->ops.target.offset >= (s64)symbol__size(sym))
 		return false;
 
@@ -2201,7 +2200,7 @@ void annotation__mark_jump_targets(struct annotation *notes, struct symbol *sym)
 
 		dl = disasm_line(al);
 
-		if (!disasm_line__is_valid_jump(dl, sym))
+		if (!disasm_line__is_valid_local_jump(dl, sym))
 			continue;
 
 		al = notes->offsets[dl->ops.target.offset];
diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
index ad8baafaf9f9..ff7e3df31efa 100644
--- a/tools/perf/util/annotate.h
+++ b/tools/perf/util/annotate.h
@@ -117,12 +117,20 @@ static inline struct disasm_line *disasm_line(struct annotation_line *al)
 	return al ? container_of(al, struct disasm_line, al) : NULL;
 }
 
-static inline bool disasm_line__has_offset(const struct disasm_line *dl)
+/*
+ * Is this offset in the same function as the line it is used?
+ * asm functions jump to other functions, for instance.
+ */
+static inline bool disasm_line__has_local_offset(const struct disasm_line *dl)
 {
-	return dl->ops.target.offset_avail;
+	return dl->ops.target.offset_avail && !dl->ops.target.outside;
 }
 
-bool disasm_line__is_valid_jump(struct disasm_line *dl, struct symbol *sym);
+/*
+ * Can we draw an arrow from the jump to its target, for instance? I.e.
+ * is the jump and its target in the same function?
+ */
+bool disasm_line__is_valid_local_jump(struct disasm_line *dl, struct symbol *sym);
 
 void disasm_line__free(struct disasm_line *dl);
 struct annotation_line *
-- 
2.14.3