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perf tools: Fix truncated annotation

PATCH In review Ingo Molnar 1 participant 2 messages Dec 23, 2011 – Dec 29, 2011 perf events

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PATCH 1/1 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

tools/perf/util/annotate.c +1 -1
Index: 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);
#1 lore raw
Commit-ID:  f41612f43be9575e1160460b08c3a760e6e27e1b
Gitweb:     http://git.kernel.org/tip/f41612f43be9575e1160460b08c3a760e6e27e1b
Author:     Ingo Molnar <[email protected]>
AuthorDate: Fri, 23 Dec 2011 14:08:04 +0100
Committer:  Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Fri, 23 Dec 2011 16:39:19 -0200

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.

---
 tools/perf/util/annotate.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
tools/perf/util/annotate.c +1 -1
index 376e643..011ed26 100644
@@ -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);