1. 07 Jun, 2015 5 commits
  2. 04 Jun, 2015 1 commit
  3. 03 Jun, 2015 1 commit
    • Wang Nan's avatar
      perf tools: Deal with kernel module names in '[]' correctly · 1f121b03
      Wang Nan authored
      Before patch ba92732e ('perf kmaps: Check kmaps to make code more
      robust'), 'perf report' and 'perf annotate' will segfault if trace data
      contains kernel module information like this:
      
       # perf report -D -i ./perf.data
       ...
       0 0 0x188 [0x50]: PERF_RECORD_MMAP -1/0: [0xffffffbff1018000(0xf068000) @ 0]: x [test_module]
       ...
      
       # perf report -i ./perf.data --objdump=/path/to/objdump --kallsyms=/path/to/kallsyms
      
       perf: Segmentation fault
       -------- backtrace --------
       /path/to/perf[0x503478]
       /lib64/libc.so.6(+0x3545f)[0x7fb201f3745f]
       /path/to/perf[0x499b56]
       /path/to/perf(dso__load_kallsyms+0x13c)[0x49b56c]
       /path/to/perf(dso__load+0x72e)[0x49c21e]
       /path/to/perf(map__load+0x6e)[0x4ae9ee]
       /path/to/perf(thread__find_addr_map+0x24c)[0x47deec]
       /path/to/perf(perf_event__preprocess_sample+0x88)[0x47e238]
       /path/to/perf[0x43ad02]
       /path/to/perf[0x4b55bc]
       /path/to/perf(ordered_events__flush+0xca)[0x4b57ea]
       /path/to/perf[0x4b1a01]
       /path/to/perf(perf_session__process_events+0x3be)[0x4b428e]
       /path/to/perf(cmd_report+0xf11)[0x43bfc1]
       /path/to/perf[0x474702]
       /path/to/perf(main+0x5f5)[0x42de95]
       /lib64/libc.so.6(__libc_start_main+0xf4)[0x7fb201f23bd4]
       /path/to/perf[0x42dfc4]
      
      This is because __kmod_path__parse treats '[' leading names as kernel
      name instead of names of kernel module.
      
      If perf.data contains build information and the buildid of such modules
      can be found, the dso->kernel of it will be set to DSO_TYPE_KERNEL by
      __event_process_build_id(), not kernel module.
      
      It will then be passed to dso__load() -> dso__load_kernel_sym() ->
      dso__load_kcore() if --kallsyms is provided.
      
      The refered patch adds NULL pointer checker to avoid segfault. However,
      such kernel modules are still processed incorrectly.
      
      This patch fixes __kmod_path__parse, makes it treat names like
      '[test_module]' as kernel modules.
      
      kmod-path.c is also update to reflect the above changes.
      Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
      Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Zefan Li <lizefan@huawei.com>
      Link: http://lkml.kernel.org/r/1433321541-170245-1-git-send-email-wangnan0@huawei.com
      [ Fixed the merged with 0443f36b ("perf machine: Fix the search
        for the kernel DSO on the unified list" ]
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      1f121b03
  4. 02 Jun, 2015 3 commits
  5. 01 Jun, 2015 1 commit
  6. 30 May, 2015 1 commit
    • Wang Nan's avatar
      perf probe: Fix segfault when glob matching function without debuginfo · 6bb536cc
      Wang Nan authored
      Commit 4c859351 ("perf probe: Support
      glob wildcards for function name") introduces segfault problems when
      debuginfo is not available:
      
       # perf probe 'sys_w*'
        Added new events:
        Segmentation fault
      
      The first problem resides in find_probe_trace_events_from_map(). In
      that function, find_probe_functions() is called to match each symbol
      against glob to find the number of matching functions, but still use
      map__for_each_symbol_by_name() to find 'struct symbol' for matching
      functions. Unfortunately, map__for_each_symbol_by_name() does
      exact matching by searching in an rbtree.
      
      It doesn't know glob matching, and not easy for it to support it because
      it use rbtree based binary search, but we are unable to ensure all names
      matched by the glob (any glob passed by user) reside in one subtree.
      
      This patch drops map__for_each_symbol_by_name(). Since there is no
      rbtree again, re-matching all symbols costs a lot. This patch avoid it
      by saving all matching results into an array (syms).
      
      The second problem is the lost of tp->realname. In
      __add_probe_trace_events(), if pev->point.function is glob, the event
      name should be set to tev->point.realname. This patch ensures its
      existence by strdup sym->name instead of leaving a NULL pointer there.
      
      After this patch:
      
       # perf probe 'sys_w*'
       Added new events:
         probe:sys_waitid     (on sys_w*)
         probe:sys_wait4      (on sys_w*)
         probe:sys_waitpid    (on sys_w*)
         probe:sys_write      (on sys_w*)
         probe:sys_writev     (on sys_w*)
      
       You can now use it in all perf tools, such as:
      
               perf record -e probe:sys_writev -aR sleep 1
      Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
      Acked-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Zefan Li <lizefan@huawei.com>
      Link: http://lkml.kernel.org/r/1432892747-232506-1-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      6bb536cc
  7. 29 May, 2015 15 commits
  8. 28 May, 2015 3 commits
  9. 27 May, 2015 10 commits