1. 19 4月, 2010 1 次提交
  2. 03 4月, 2010 2 次提交
  3. 26 3月, 2010 2 次提交
  4. 25 2月, 2010 1 次提交
    • A
      perf symbols: Improve debugging information about symtab origins · 3846df2e
      Arnaldo Carvalho de Melo 提交于
      Be more clear about DSO long names and tell from which file
      kernel symbols were obtained, all in --verbose mode:
      
          [root@mica ~]# perf report -v > /dev/null
          Looking at the vmlinux_path (5 entries long)
          Using /lib/modules/2.6.33-rc8-tip-00777-g0918527-dirty/build/vmlinux for symbols
          [root@mica ~]# mv /lib/modules/2.6.33-rc8-tip-00777-g0918527-dirty/build/vmlinux /tmp/dd
          [root@mica ~]# perf report -v > /dev/null
          Looking at the vmlinux_path (5 entries long)
          Using /proc/kallsyms for symbols
          [root@mica ~]#
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frédéric Weisbecker <fweisbec@gmail.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Paul Mackerras <paulus@samba.org>
      LKML-Reference: <1266866139-6361-1-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      3846df2e
  5. 08 2月, 2010 1 次提交
    • K
      perf top: Fix annotate for userspace · ee11b90b
      Kirill Smelkov 提交于
      First, for programs and prelinked libraries, annotate code was
      fooled by objdump output IPs (src->eip in the code) being
      wrongly converted to absolute IPs. In such case there were no
      conversion needed, but in
      
         src->eip = strtoull(src->line, NULL, 16);
         src->eip = map->unmap_ip(map, src->eip); // = eip + map->start - map->pgoff
      
      we were reading absolute address from objdump (e.g. 8048604) and
      then almost doubling it, because eip & map->start are
      approximately close for small programs.
      
      Needless to say, that later, in record_precise_ip() there was no
      matching with real runtime IPs.
      
      And second, like with `perf annotate` the problem with
      non-prelinked *.so was that we were doing rip -> objdump address
      conversion wrong.
      
      Also, because unlike `perf annotate`, `perf top` code does
      annotation based on absolute IPs for performance reasons(*), new
      helper for mapping objdump addresse to IP is introduced.
      
      (*) we get samples info in absolute IPs, and since we do lots of
          hit-testing on absolute IPs at runtime in record_precise_ip(), it's
          better to convert objdump addresses to IPs once and do no conversion
          at runtime.
      
      I also had to fix how objdump output is parsed (with hardcoded
      8/16 characters format, which was inappropriate for ET_DYN dsos
      with small addresses like '4ac')
      
      Also note, that not all objdump output lines has associtated
      IPs, e.g. look at source lines here:
      
          000004ac <my_strlen>:
          extern "C"
          int my_strlen(const char *s)
           4ac:   55                      push   %ebp
           4ad:   89 e5                   mov    %esp,%ebp
           4af:   83 ec 10                sub    $0x10,%esp
          {
              int len = 0;
           4b2:   c7 45 fc 00 00 00 00    movl   $0x0,-0x4(%ebp)
           4b9:   eb 08                   jmp    4c3 <my_strlen+0x17>
      
              while (*s) {
                  ++len;
           4bb:   83 45 fc 01             addl   $0x1,-0x4(%ebp)
                  ++s;
           4bf:   83 45 08 01             addl   $0x1,0x8(%ebp)
      
      So we mark them with eip=0, and ignore such lines in annotate
      lookup code.
      Signed-off-by: NKirill Smelkov <kirr@landau.phys.spbu.ru>
      [ Note: one hunk of this patch was applied by Mike in 57d81889 ]
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Mike Galbraith <efault@gmx.de>
      LKML-Reference: <1265550376-12665-1-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      ee11b90b
  6. 04 2月, 2010 2 次提交
    • K
      perf annotate: Fix it for non-prelinked *.so · 7a2b6209
      Kirill Smelkov 提交于
      The problem was we were incorrectly calculating objdump
      addresses for sym->start and sym->end, look:
      
      For simple ET_DYN type DSO (*.so) with one function, objdump -dS
      output is something like this:
      
          000004ac <my_strlen>:
          int my_strlen(const char *s)
           4ac:   55                      push   %ebp
           4ad:   89 e5                   mov    %esp,%ebp
           4af:   83 ec 10                sub    $0x10,%esp
          {
      
      i.e. we have relative-to-dso-mapping IPs (=RIP) there.
      
      For ET_EXEC type and probably for prelinked libs as well (sorry
      can't test - I don't use prelink) objdump outputs absolute IPs,
      e.g.
      
          08048604 <zz_strlen>:
          extern "C"
          int zz_strlen(const char *s)
           8048604:       55                      push   %ebp
           8048605:       89 e5                   mov    %esp,%ebp
           8048607:       83 ec 10                sub    $0x10,%esp
          {
      
      So, if sym->start is always relative to dso mapping(*), we'll
      have to unmap it for ET_EXEC like cases, and leave as is for
      ET_DYN cases.
      
      (*) and it is - we've explicitely made it relative. Look for
          adjust_symbols handling in dso__load_sym()
      
      Previously we were always unmapping sym->start and for ET_DYN
      dsos resulting addresses were wrong, and so objdump output was
      empty.
      
      The end result was that perf annotate output for symbols from
      non-prelinked *.so had always 0.00% percents only, which is
      wrong.
      
      To fix it, let's introduce a helper for converting rip to
      objdump address, and also let's document what map_ip() and
      unmap_ip() do -- I had to study sources for several hours to
      understand it.
      Signed-off-by: NKirill Smelkov <kirr@landau.phys.spbu.ru>
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Mike Galbraith <efault@gmx.de>
      LKML-Reference: <1265223128-11786-8-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7a2b6209
    • A
      perf symbols: Remove perf_session usage in symbols layer · 9de89fe7
      Arnaldo Carvalho de Melo 提交于
      I noticed while writing the first test in 'perf regtest' that to
      just test the symbol handling routines one needs to create a
      perf session, that is a layer centered on a perf.data file,
      events, etc, so I untied these layers.
      
      This reduces the complexity for the users as the number of
      parameters to most of the symbols and session APIs now was
      reduced while not adding more state to all the map instances by
      only having data that is needed to split the kernel (kallsyms
      and ELF symtab sections) maps and do vmlinux relocation on the
      main kernel map.
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frédéric Weisbecker <fweisbec@gmail.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Paul Mackerras <paulus@samba.org>
      LKML-Reference: <1265223128-11786-1-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      9de89fe7
  7. 28 12月, 2009 1 次提交