1. 26 3月, 2010 2 次提交
  2. 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
  3. 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
  4. 04 2月, 2010 3 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: Ditch vdso global variable · 8d92c02a
      Arnaldo Carvalho de Melo 提交于
      We can check using strcmp, most DSOs don't start with '[' so the
      test is cheap enough and we had to test it there anyway since
      when reading perf.data files we weren't calling the routine that
      created this global variable and thus weren't setting it as
      "loaded", which was causing a bogus:
      
        Failed to open [vdso], continuing without symbols
      
      Message as the first line of 'perf report'.
      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: <1265223128-11786-3-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8d92c02a
    • 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
  5. 16 12月, 2009 1 次提交
    • M
      perf probe: Check build-id of vmlinux · a128168d
      Masami Hiramatsu 提交于
      Check build-id of vmlinux by using functions in symbol.c.
      This also exposes map__load() for getting vmlinux path,
      and removes vmlinux path list in builtin-probe.c,
      because symbol.c already has that. Checking build-id
      prevents users to open old or different debuginfo from
      current running kernel.
      Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: systemtap <systemtap@sources.redhat.com>
      Cc: DLE <dle-develop@lists.sourceforge.net>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091215153232.17436.45539.stgit@dhcp-100-2-132.bos.redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a128168d
  6. 14 12月, 2009 1 次提交
    • A
      perf session: Move kmaps to perf_session · 4aa65636
      Arnaldo Carvalho de Melo 提交于
      There is still some more work to do to disentangle map creation
      from DSO loading, but this happens only for the kernel, and for
      the early adopters of perf diff, where this disentanglement
      matters most, we'll be testing different kernels, so no problem
      here.
      
      Further clarification: right now we create the kernel maps for
      the various modules and discontiguous kernel text maps when
      loading the DSO, we should do it as a two step process, first
      creating the maps, for multiple mappings with the same DSO
      store, then doing the dso load just once, for the first hit on
      one of the maps sharing this DSO backing store.
      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: <1260741029-4430-6-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      4aa65636
  7. 12 12月, 2009 2 次提交
    • A
      perf symbols: Ditch dso->find_symbol · ea08d8cb
      Arnaldo Carvalho de Melo 提交于
      It is always wired to dso__find_symbol.
      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: <1260564999-13371-1-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      ea08d8cb
    • A
      perf symbols: Allow lookups by symbol name too · 79406cd7
      Arnaldo Carvalho de Melo 提交于
      Configurable via symbol_conf.sort_by_name, so that the cost of an
      extra rb_node on all 'struct symbol' instances is not paid by tools
      that only want to decode addresses.
      
      How to use it:
      
      	symbol_conf.sort_by_name = true;
      	symbol_init(&symbol_conf);
      
      	struct map *map = map_groups__find_by_name(kmaps, MAP__VARIABLE, "[kernel.kallsyms]");
      
      	if (map == NULL) {
      		pr_err("couldn't find map!\n");
      		kernel_maps__fprintf(stdout);
      	} else {
      		struct symbol *sym = map__find_symbol_by_name(map, sym_filter, NULL);
      		if (sym == NULL)
      			pr_err("couldn't find symbol %s!\n", sym_filter);
      		else
      			pr_info("symbol %s: %#Lx-%#Lx \n", sym_filter, sym->start, sym->end);
      	}
      
      Looking over the vmlinux/kallsyms is common enough that I'll add a
      variable to the upcoming struct perf_session to avoid the need to
      use map_groups__find_by_name to get the main vmlinux/kallsyms map.
      
      The above example looks on the 'variable' symtab, but it is just
      like that for the functions one.
      
      Also the sort operation is done when we first use
      map__find_symbol_by_name, in a lazy way.
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frédéric Weisbecker <fweisbec@gmail.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Paul Mackerras <paulus@samba.org>
      LKML-Reference: <1260564622-12392-1-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      79406cd7
  8. 28 11月, 2009 2 次提交
  9. 24 11月, 2009 1 次提交
  10. 21 11月, 2009 1 次提交
    • A
      perf symbols: Do lazy symtab loading for the kernel & modules too · c338aee8
      Arnaldo Carvalho de Melo 提交于
      Just like we do with the other DSOs. This also simplifies the
      kernel_maps setup process, now all that the tools need to do is
      to call kernel_maps__init and the maps for the modules and
      kernel will be created, then, later, when
      kernel_maps__find_symbol() is used, it will also call
      maps__find_symbol that already checks if the symtab was loaded,
      loading it if needed.
      
      Now if one does 'perf top --hide_kernel_symbols' we won't pay
      the price of loading the (many) symbols in /proc/kallsyms or
      vmlinux.
      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: <1258757489-5978-4-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      c338aee8
  11. 08 11月, 2009 1 次提交
    • A
      perf symbols: Use the buildids if present · 8d06367f
      Arnaldo Carvalho de Melo 提交于
      With this change 'perf record' will intercept PERF_RECORD_MMAP
      calls, creating a linked list of DSOs, then when the session
      finishes, it will traverse this list and read the buildids,
      stashing them at the end of the file and will set up a new
      feature bit in the header bitmask.
      
      'perf report' will then notice this feature and populate the
      'dsos' list and set the build ids.
      
      When reading the symtabs it will refuse to load from a file that
      doesn't have the same build id. This improves the
      reliability of the profiler output, as symbols and profiling
      data is more guaranteed to match.
      
      Example:
      
       [root@doppio ~]# perf report | head
       /home/acme/bin/perf with build id b1ea544ac3746e7538972548a09aadecc5753868 not found, continuing without symbols
        # Samples: 2621434559
        #
        # Overhead          Command                  Shared Object  Symbol
        # ........  ...............  .............................  ......
        #
             7.91%             init  [kernel]        [k] read_hpet
             7.64%             init  [kernel]        [k] mwait_idle_with_hints
             7.60%          swapper  [kernel]        [k] read_hpet
             7.60%          swapper  [kernel]        [k] mwait_idle_with_hints
             3.65%             init  [kernel]        [k] 0xffffffffa02339d9
      [root@doppio ~]#
      
      In this case the 'perf' binary was an older one, vanished,
      so its symbols probably wouldn't match or would cause subtly
      different (and misleading) output.
      
      Next patches will support the kernel as well, reading the build
      id notes for it and the modules from /sys.
      
      Another patch should also introduce a new plumbing command:
      
      'perf list-buildids'
      
      that will then be used in porcelain that is distro specific to
      fetch -debuginfo packages where such buildids are present. This
      will in turn allow for one to run 'perf record' in one machine
      and 'perf report' in another.
      
      Future work on having the buildid sent directly from the kernel
      in the PERF_RECORD_MMAP event is needed to close races, as the
      DSO can be changed during a 'perf record' session, but this
      patch at least helps with non-corner cases and current/older
      kernels.
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: Jim Keniston <jkenisto@us.ibm.com>
      Cc: K. Prasad <prasad@linux.vnet.ibm.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Roland McGrath <roland@redhat.com>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      LKML-Reference: <1257367843-26224-1-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8d06367f
  12. 03 11月, 2009 1 次提交
    • I
      perf tools: Fix missing symtabs printouts · 900b20d5
      Ingo Molnar 提交于
      Fix:
      
        util/map.c: In function ‘map__find_symbol’:
        util/map.c:97: error: field precision should have type ‘int’, but argument 3 has type ‘size_t’
      
      Also clean up some line wrap damage - we dont line-wrap printk
      messages.
      
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Mike Galbraith <efault@gmx.de>
      LKML-Reference: <1256927305-4628-3-git-send-email-acme@infradead.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      900b20d5
  13. 02 11月, 2009 3 次提交
  14. 29 10月, 2009 1 次提交
  15. 23 10月, 2009 1 次提交
    • A
      perf tools: Unify debug messages mechanisms · 6beba7ad
      Arnaldo Carvalho de Melo 提交于
      We were using eprintf in some places, that looks at a global
      'verbose' level, and at other places passing a 'v' parameter to
      specify the verbosity level, unify it by introducing
      pr_{err,warning,debug,etc}, just like in the kernel.
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Mike Galbraith <efault@gmx.de>
      LKML-Reference: <1256153646-10097-1-git-send-email-acme@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      6beba7ad
  16. 21 10月, 2009 1 次提交
  17. 20 10月, 2009 1 次提交
    • A
      perf tools: Add ->unmap_ip operation to struct map · ed52ce2e
      Arnaldo Carvalho de Melo 提交于
      We need this because we get section relative addresses when
      reading the symtabs, but when a tool like 'perf annotate' needs
      to match these address to what 'objdump -dS' produces we need
      the address + section back again.
      
      So in annotate now we look at the 'struct hist_entry' instances
      (that weren't really being used) so that we iterate only over
      the symbols that had some hit and get the map where that
      particular hit happened so that we can get the right address to
      match with annotate.
      
      Verified that at least:
      
       perf annotate mmap_read_counter # Uses the ~/bin/perf binary
       perf annotate --vmlinux /home/acme/git/build/perf/vmlinux intel_pmu_enable_all
      
      on a 'perf record perf top' session seems to work.
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Mike Galbraith <efault@gmx.de>
      LKML-Reference: <1255979877-12533-1-git-send-email-acme@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      ed52ce2e
  18. 12 8月, 2009 1 次提交