Re: [PATCH 14/18] perf tools: Make vmlinux short name more like kallsyms short name

[Jiri Olsa <jolsa@redhat.com>]

On Thu, Nov 06, 2014 at 06:04:35PM -0300, Arnaldo Carvalho de Melo wrote:
> From: Namhyung Kim <namhyung@kernel.org>
> 
> The previous patch changed kernel dso name from '[kernel.kallsyms]' to
> vmlinux.  However it might add confusion to old users accustomed to the
> old name.  So change the short name to '[kernel.vmlinux]' to reduce such
> confusion.
> 

SNIP

> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> ---
>  tools/perf/util/machine.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> index 53f90e9c65fe..52e94902afb1 100644
> --- a/tools/perf/util/machine.c
> +++ b/tools/perf/util/machine.c
> @@ -1106,6 +1106,9 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
>  		if (__machine__create_kernel_maps(machine, kernel) < 0)
>  			goto out_problem;
>  
> +		if (strstr(dso->long_name, "vmlinux"))
> +			dso__set_short_name(dso, "[kernel.vmlinux]", false);
> +

heya,
I've got attached segfault in perf script because of this,
if I revert it's ok..

jirka

[jolsa@krava perf]$ ./perf record -e instructions -c 100000000 yes > /dev/null
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data (~576 samples) ]
[jolsa@krava perf]$ gdb ./perf
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Reading symbols from ./perf...done.
(gdb) r script
Starting program: /home/jolsa/kernel.org/linux-perf/tools/perf/perf script
warning: section  not found in /usr/lib/debug/lib/modules/3.16.6-203.fc20.x86_64/vdso/vdso64.so.debug
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Detaching after fork from child process 6849.
Program received signal SIGSEGV, Segmentation fault.
__strstr_sse42 (s1=0x0, s2=0x5db702 "vmlinux") at ../sysdeps/x86_64/multiarch/strstr.c:175
175       if (__builtin_expect (p1[0] == '\0', 0))
Missing separate debuginfos, use: debuginfo-install audit-libs-2.4-2.fc20.x86_64 elfutils-libelf-0.160-1.fc20.x86_64 elfutils-libs-0.160-1.fc20.x86_64 libunwind-1.1-3.fc20.x86_64 nss-softokn-freebl-3.17.2-1.fc20.x86_64 numactl-libs-2.0.9-2.fc20.x86_64 perl-libs-5.18.4-290.fc20.x86_64 python-libs-2.7.5-14.fc20.x86_64 slang-2.2.4-11.fc20.x86_64 xz-libs-5.1.2-12alpha.fc20.x86_64 zlib-1.2.8-3.fc20.x86_64
(gdb) bt
#0  __strstr_sse42 (s1=0x0, s2=0x5db702 "vmlinux") at ../sysdeps/x86_64/multiarch/strstr.c:175
#1  0x00000000004a881d in machine__process_kernel_mmap_event (machine=0x8d3e80, event=0x7ffff7ff50d8)
    at util/machine.c:1109
#2  0x00000000004a8b4f in machine__process_mmap_event (machine=0x8d3e80, event=0x7ffff7ff50d8,
    sample=0x7fffffffd280) at util/machine.c:1203
#3  0x0000000000470e7e in perf_event__process_mmap (tool=0x7fffffffd650, event=0x7ffff7ff50d8,
    sample=0x7fffffffd280, machine=0x8d3e80) at util/event.c:666
#4  0x00000000004af2fa in perf_session__deliver_event (session=0x8d3dc0, event=0x7ffff7ff50d8,
    sample=0x7fffffffd280, tool=0x7fffffffd650, file_offset=216) at util/session.c:845
#5  0x00000000004afa96 in perf_session__process_event (session=0x8d3dc0, event=0x7ffff7ff50d8,
    tool=0x7fffffffd650, file_offset=216) at util/session.c:1020
#6  0x00000000004b0451 in __perf_session__process_events (session=0x8d3dc0, data_offset=216, data_size=16240,
    file_size=16456, tool=0x7fffffffd650) at util/session.c:1292
#7  0x00000000004b061e in perf_session__process_events (session=0x8d3dc0, tool=0x7fffffffd650)
    at util/session.c:1337
#8  0x00000000004453d4 in __cmd_script (script=0x7fffffffd650) at builtin-script.c:803
#9  0x0000000000448858 in cmd_script (argc=0, argv=0x7fffffffe2e0, prefix=0x0) at builtin-script.c:1835
#10 0x000000000041c88c in run_builtin (p=0x856f70 <commands+336>, argc=1, argv=0x7fffffffe2e0) at perf.c:331
#11 0x000000000041caeb in handle_internal_command (argc=1, argv=0x7fffffffe2e0) at perf.c:390
#12 0x000000000041cc37 in run_argv (argcp=0x7fffffffe13c, argv=0x7fffffffe130) at perf.c:434
#13 0x000000000041cf8e in main (argc=1, argv=0x7fffffffe2e0) at perf.c:549
(gdb) q
A debugging session is active.