linux-kernel - [PATCH] perf tools: Fix truncated annotation

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Message-ID: <20111223130804.GA24305@elte.hu>
Date:	Fri, 23 Dec 2011 14:08:04 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Arnaldo Carvalho de Melo <acme@...hat.com>
Cc:	linux-kernel@...r.kernel.org,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>
Subject: [PATCH] perf tools: Fix truncated annotation


I get such truncated annotation results in 'perf top':

         :        Disassembly of section .text:                                                   ▒
         :                                                                                        ▒
         :        ffffffff810966a8 <nr_iowait_cpu>:                                               ▒
    4.94 :        ffffffff810966a8:       movslq %edi,%rdi                                        ▒
    3.70 :        ffffffff810966ab:       mov    $0x13700,%rax                                    ▒
    0.00 :        ffffffff810966b2:       add    -0x7e32cb00(,%rdi,8),%rax                        ▒
    8.64 :        ffffffff810966ba:       mov    0x7e0(%rax),%eax                                 ▒
   82.72 :        ffffffff810966c0:       cltq                                                    ▒

Note the missing 'retq' which is there in the original function:

ffffffff810966a8 <nr_iowait_cpu>:
ffffffff810966a8:       48 63 ff                movslq %edi,%rdi
ffffffff810966ab:       48 c7 c0 00 37 01 00    mov    $0x13700,%rax
ffffffff810966b2:       48 03 04 fd 00 35 cd    add    -0x7e32cb00(,%rdi,8),%rax
ffffffff810966b9:       81 
ffffffff810966ba:       8b 80 e0 07 00 00       mov    0x7e0(%rax),%eax
ffffffff810966c0:       48 98                   cltq   
ffffffff810966c2:       c3                      retq   

ffffffff810966c3 <this_cpu_load>:

I'm using a fairly recent binutils:

  GNU objdump version 2.21.51.0.6-2.fc16 20110118

AFAICS the bug is simply that sym->end points to the last byte 
of the symbol in question - while objdump's --stop-address 
expects the last byte plus 1 to disassemble the full range.

Thanks,

	Ingo

Signed-off-by: Ingo Molnar <mingo@...e.hu>

Index: linux/tools/perf/util/annotate.c
===================================================================
--- linux.orig/tools/perf/util/annotate.c
+++ linux/tools/perf/util/annotate.c
@@ -334,7 +334,7 @@ fallback:
 		 disassembler_style ? "-M " : "",
 		 disassembler_style ? disassembler_style : "",
 		 map__rip_2objdump(map, sym->start),
-		 map__rip_2objdump(map, sym->end),
+		 map__rip_2objdump(map, sym->end+1),
 		 symbol_conf.annotate_asm_raw ? "" : "--no-show-raw",
 		 symbol_conf.annotate_src ? "-S" : "",
 		 symfs_filename, filename);
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