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  • Masami Hiramatsu's avatar
    perf probe: Find given address from offline dwarf · f90acac7
    Masami Hiramatsu authored
    
    
    Find the given address from offline dwarfs instead of online kernel
    dwarfs.
    
    On the KASLR enabled kernel, the kernel text section is loaded with
    random offset, and the debuginfo__new_online_kernel can't handle it. So
    let's move to the offline dwarf loader instead of using the online dwarf
    loader.
    
    As a result, since we don't need debuginfo__new_online_kernel any more,
    this also removes the functions related to that.
    
    Without this change;
    
      # ./perf probe -l
        probe:t_show         (on _stext+901288 with m v)
        probe:t_show_1       (on _stext+939624 with m v t)
        probe:t_show_2       (on _stext+980296 with m v fmt)
        probe:t_show_3       (on _stext+1014392 with m v file)
    
    With this change;
    
      # ./perf probe -l
        probe:t_show         (on t_show@linux-3/kernel/trace/ftrace.c with m v)
        probe:t_show_1       (on t_show@linux-3/kernel/trace/trace.c with m v t)
        probe:t_show_2       (on t_show@kernel/trace/trace_printk.c with m v fmt)
        probe:t_show_3       (on t_show@kernel/trace/trace_events.c with m v file)
    
    Changes from v2:
     - Instead of retrying, directly opens offline dwarf.
     - Remove debuginfo__new_online_kernel and related functions.
     - Refer map->reloc to get the correct address of a symbol.
     - Add a special case for handling ref_reloc_sym based address.
    
    Signed-off-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
    Cc: David Ahern <dsahern@gmail.com>
    Cc: "David A. Long" <dave.long@linaro.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Oleg Nesterov <oleg@redhat.com>
    Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
    Cc: Steven Rostedt <rostedt@goodmis.org>
    Cc: yrl.pp-manager.tt@hitachi.com
    Link: http://lkml.kernel.org/r/20140206053218.29635.74821.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
    
    
    Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    f90acac7