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  1. 22 1月, 2015 14 次提交
  3. 21 1月, 2015 9 次提交
  5. 17 1月, 2015 9 次提交
    • S
      perf tools powerpc: Use dwfl_report_elf() instead of offline. · 6bcf9c1f
      由 Sukadev Bhattiprolu 提交于 
      dwfl_report_offline() works only when libraries are prelinked.

Replace dwfl_report_offline() with dwfl_report_elf() so we correctly
extract debug info even from libraries that are not prelinked.
Reported-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Tested-by: NJiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: http://lkml.kernel.org/r/20150114221045.GA17703@us.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      6bcf9c1f
    • N
      perf tools: Fix segfault for symbol annotation on TUI · 813ccd15
      由 Namhyung Kim 提交于 
      Currently the symbol structure is allocated with symbol_conf.priv_size
to carry sideband information like annotation, map browser on TUI and
sort-by-name tree node.  So retrieving these information from symbol
needs to care about the details of such placement.

However the annotation code just assumes that the symbol is placed after
the struct annotation.  But actually there's other info between them.
So accessing those struct will lead to an undefined behavior (usually a
crash) after they write their info to the same location.

To reproduce the problem, please follow the steps below:

  1. run perf report (TUI of course) with -v option
  2. open map browser (by pressing right arrow key for any entry)
  3. search any function (by pressing '/' key and input whatever..)
  4. return to the hist browser (by pressing 'q' or left arrow key)
  5. open annotation window for the same entry (by pressing 'a' key)
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1421234288-22758-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      813ccd15
    • W
      perf test: Fix dwarf unwind using libunwind. · b93b0967
      由 Wang Nan 提交于 
      Perf tool fails to unwind user stack if the event raises in a shared
object. This patch improves tests/dwarf-unwind.c to demonstrate the
problem by utilizing commonly used glibc function "bsearch". If perf is
not statically linked, the testcase will try to unwind a mixed call
trace.

By debugging libunwind I found that there is a bug in unwind-libunwind:
it always passes 0 as segbase to libunwind, cause libunwind unable to
locate debug_frame entry fir first level ip address (I add some more
debugging output into libunwind to make things clear):

               >_Uarm_dwarf_find_debug_frame: start_ip = 10be98, end_ip = 10c2a4
               >_Uarm_dwarf_find_debug_frame: found debug_frame table `/lib/libc-2.18.so': segbase=0x0, len=7, gp=0x0, table_data=0x449388
               >_Uarm_dwarf_search_unwind_table: call lookup:ip = b6cd3bcc, segbase = 0, rel_ip = b6cd3bcc
               >lookup: e->start_ip_offset = bcf18 (rel_ip = b6cd3bcc)
               >lookup: e->start_ip_offset = 6d314 (rel_ip = b6cd3bcc)
               >lookup: e->start_ip_offset = 33d0c (rel_ip = b6cd3bcc)
                ...
               >lookup: e->start_ip_offset = 15d0c (rel_ip = b6cd3bcc)
               >lookup: e->start_ip_offset = 15c40 (rel_ip = b6cd3bcc)
 >_Uarm_dwarf_search_unwind_table: IP b6cd3bcc inside range b6c12000-b6d4c000, but no explicit unwind info found
                >put_rs_cache: unmasking signals/interrupts and releasing lock
               >_Uarm_dwarf_step: returning -10
 >_Uarm_step: dwarf_step()=-10

This patch passes map->start as segbase to dwarf_find_debug_frame(), so
di will be initialized correctly.

In addition, dso and executable are different when setting segbase. This
patch first check whether the elf is executable, and pass segbase only
for shared object.
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1421203007-75799-1-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b93b0967
    • V
      perf tools: Avoid build splat for syscall numbers with uclibc · ea1fe3a8
      由 Vineet Gupta 提交于 
      This is due to duplicated unistd inclusion (via uClibc headers + kernel headers)
Also seen on ARM uClibc based tools

   ------- ARC build ---------->8-------------

  CC       util/evlist.o
In file included from
~/arc/k.org/arch/arc/include/uapi/asm/unistd.h:25:0,
                 from util/../perf-sys.h:10,
                 from util/../perf.h:15,
                 from util/event.h:7,
                 from util/event.c:3:
~/arc/k.org/include/uapi/asm-generic/unistd.h:906:0:
warning: "__NR_fcntl64" redefined [enabled by default]
 #define __NR_fcntl64 __NR3264_fcntl
 ^
In file included from
~/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/sys/syscall.h:24:0,
                 from util/../perf-sys.h:6,
   ----------------->8-------------------

   ------- ARM build ---------->8-------------

  CC FPIC  plugin_scsi.o
In file included from util/../perf-sys.h:9:0,
                 from util/../perf.h:15,
                 from util/cache.h:7,
                 from perf.c:12:
~/arc/k.org/arch/arm/include/uapi/asm/unistd.h:28:0:
warning: "__NR_restart_syscall" redefined [enabled by default]
In file included from
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/sys/syscall.h:25:0,
                 from util/../perf-sys.h:6,
                 from util/../perf.h:15,
                 from util/cache.h:7,
                 from perf.c:12:
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/bits/sysnum.h:17:0:
note: this is the location of the previous definition
   ----------------->8-------------------
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421156604-30603-4-git-send-email-vgupta@synopsys.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      ea1fe3a8
    • V
      perf tools: Elide strlcpy warning with uclibc · a83d869f
      由 Vineet Gupta 提交于 
         ----------------->8------------------
  CC       bench/sched-pipe.o
In file included from builtin-annotate.c:13:0:
util/cache.h:76:15: warning: redundant redeclaration of 'strlcpy'
[-Wredundant-decls]
 extern size_t strlcpy(char *dest, const char *src, size_t size);
               ^
In file included from util/util.h:55:0,
                 from builtin.h:4,
                 from builtin-annotate.c:8:
~/vineetg/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/string.h:396:15:
note: previous declaration of 'strlcpy' was here
 extern size_t strlcpy(char *__restrict dst, const char *__restrict src,
   ----------------->8------------------
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421156604-30603-3-git-send-email-vgupta@synopsys.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a83d869f
    • A
      tools: Remove bitops/hweight usage of bits in tools/perf · 25cd480e
      由 Arnaldo Carvalho de Melo 提交于 
      We need to use lib/hweight.c for that, just like we do for lib/rbtree.c,
so tools need to link hweight.o. For now do it directly, but we need to
have a tools/lib/lk.a or .so that collects these goodies...
Reported-by: NJan Beulich <JBeulich@suse.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-a1e91dx3apzqw5kbdt7ut21s@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      25cd480e
    • N
      perf machine: Fix __machine__findnew_thread() error path · 260d819e
      由 Namhyung Kim 提交于 
      When thread__init_map_groups() fails, a new thread should be removed
from the rbtree since it's gonna be freed.  Also update last match cache
only if the function succeeded.
Reported-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1420763892-15535-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      260d819e
    • N
      perf tools: Fix building error in x86_64 when dwarf unwind is on · c6e5e9fb
      由 Namhyung Kim 提交于 
      When build with 'make ARCH=x86' and dwarf unwind is on, there is a
compiling error:

   CC       /home/wn/perf/arch/x86/util/unwind-libdw.o
   CC       /home/wn/perf/arch/x86/tests/regs_load.o
 arch/x86/tests/regs_load.S: Assembler messages:
 arch/x86/tests/regs_load.S:65: Error: operand type mismatch for `push'
 arch/x86/tests/regs_load.S:72: Error: operand type mismatch for `pop'
 make[1]: *** [/home/wn/perf/arch/x86/tests/regs_load.o] Error 1
 make[1]: INTERNAL: Exiting with 25 jobserver tokens available; should be 24!
 make: *** [all] Error 2
 ...

Which is caused by incorrectly undefine macro HAVE_ARCH_X86_64_SUPPORT.
'config/Makefile.arch' tests __x86_64__ only when 'ARCH=x86_64'.
However, when building x86_64 kernel, ARCH=x86 is valid and commonly
used. Build systems, such as yocto, uses x86_64 compiler with 'ARCH=x86'
to build x86_64 perf, which causes mismatching.

As __LP64__ is defined for x86_64 as well, we can consolidate the
__x86_64__ check to the __LP64__ check and get rid of the IS_X86_64
IMHO.

(This patch is made by Namhyung Kim when replying my v1 patch:

https://lkml.org/lkml/2015/1/7/17

I modified the code to remove dependency on RAW_ARCH:

https://lkml.org/lkml/2015/1/7/865

Namhyung Kim didn't provide his SOB in his original email. I add
mine only for my modification.)
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Signed-off-by: NWang Nan <wangnan0@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1421029255-23039-1-git-send-email-wangnan0@huawei.com
[ Namhyung provided his S-o-B on a followup to this patch thread on lkml ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      c6e5e9fb
    • N
      perf probe: Propagate error code when write(2) failed · 7949ba1f
      由 Namhyung Kim 提交于 
      When it failed to write probe commands to the probe_event file in
debugfs, it needs to propagate the error code properly.  Current code
blindly uses the return value of the write(2) so it always uses
-1 (-EPERM) and it might confuse users.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1420886028-15135-4-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      7949ba1f
  7. 08 1月, 2015 3 次提交
    • N
      perf hists browser: Fix segfault when showing callchain · c09e31cc
      由 Namhyung Kim 提交于 
      When perf report on TUI shows callchain it checks first node has
siblings to determine whether it needs to print percentage value.

But it missed a case that first node is NULL.  So sometimes it segfaults
like below:

  $ perf top -g
  perf: Segmentation fault
  -------- backtrace --------
  perf[0x4fcefb]
  /usr/lib/libc.so.6(+0x33b20)[0x7f2a35839b20]
  perf(rb_next+0x8)[0x47d3d8]
  perf[0x4f6058]
  perf[0x4f833b]
  perf[0x4f8610]
  perf[0x4f209e]
  perf(ui_browser__run+0x3a)[0x4f2e6a]
  perf[0x4f94ee]
  perf(perf_evlist__tui_browse_hists+0x94)[0x4fbbf4]
  perf[0x444d10]
  /usr/lib/libpthread.so.0(+0x7314)[0x7f2a37070314]
  /usr/lib/libc.so.6(clone+0x6d)[0x7f2a358ee5bd]

  $ addr2line -e `which perf` 0x4f6058
  /home/namhyung/project/linux/tools/perf/ui/browsers/hists.c:553

I don't know why the backtrace didn't print some symbols..
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Fixes: 4087d11c ("perf hists browser: Print overhead percent value for first-level callchain")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1419401076-21700-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      c09e31cc
    • N
      perf callchain: Free callchains when hist entries are deleted · d114960c
      由 Namhyung Kim 提交于 
      Markus reported that "perf top -g" can leak ~300MB per second on his
machine.  This is partly because it missed to free callchains when hist
entries are deleted.  Fix it.
Reported-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20141230053813.GD6081@sejongSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      d114960c
    • N
      perf hists: Fix children sort key behavior · 5ca82710
      由 Namhyung Kim 提交于 
      When perf report --children resorts output fields, it tries to put
caller above the callee.  But this was only meaningful for a same thread
and doing this requires callchain enabled.  So fix its check before
comparing the callchain depth.

This also changes the hist accumulation tests: In test 3, xmalloc in
bash thread should be above than other perf threads due to alphabetical
order of comm string.  Also it's under page_fault in bash thread since
alphabetical order of dso name.  The sys_perf_event_open in perf thread
is put on the last line since it's self overhead is 0.

In test 4, the sys_perf_event_open is put above other perf entries that
have same children overhead since its callchain depth is smaller.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1419309381-2593-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      5ca82710
  9. 03 1月, 2015 2 次提交
    • N
      perf diff: Fix to sort by baseline field by default · e7024fc3
      由 Namhyung Kim 提交于 
      The currently perf diff didn't add the baseline and delta (or other
compute) fields to the sort list so output will be sorted by other
fields like alphabetical order of DSO or symbol as below example.

Fix it by adding hpp formats for the fields and provides default compare
functions.

Before:

  $ perf diff
  # Event 'cycles'
  #
  # Baseline    Delta  Shared Object       Symbol
  # ........  .......  ..................  ...............................
  #
                       [bridge]            [k] ip_sabotage_in
                       [btrfs]             [k] __etree_search.constprop.47
       0.01%           [btrfs]             [k] btrfs_file_mmap
       0.01%   -0.01%  [btrfs]             [k] btrfs_getattr
                       [e1000e]            [k] e1000_watchdog
       0.00%           [kernel.vmlinux]    [k] PageHuge
       0.00%           [kernel.vmlinux]    [k] __acct_update_integrals
       0.00%           [kernel.vmlinux]    [k] __activate_page
                       [kernel.vmlinux]    [k] __alloc_fd
       0.02%   +0.02%  [kernel.vmlinux]    [k] __alloc_pages_nodemask
       ...

After:

  # Baseline    Delta  Shared Object       Symbol
  # ........  .......  ..................  ................................
  #
      24.73%   -4.62%  perf                [.] append_chain_children
       7.96%   -1.29%  perf                [.] dso__find_symbol
       6.97%   -2.07%  libc-2.20.so        [.] vfprintf
       4.61%   +0.88%  libc-2.20.so        [.] __fprintf_chk
       4.41%   +2.43%  perf                [.] sort__comm_cmp
       4.10%   -0.16%  perf                [.] comm__str
       4.03%   -0.93%  perf                [.] machine__findnew_thread_time
       3.82%   +3.09%  perf                [.] __hists__add_entry
       2.95%   -0.18%  perf                [.] sort__dso_cmp
       ...
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1419656793-32756-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e7024fc3
    • T
      perf list: Fix --raw-dump option · b3505208
      由 Taesoo Kim 提交于 
      Currently, 'perf list --raw-dump' requires extra arguments
(e.g., hw) to invoke, which breaks bash/zsh completion
(perf-completion.sh).

  $ perf list --raw-dump
    Error: unknown option `raw-dump'

     usage: perf list [hw|sw|cache|tracepoint|pmu|event_glob]

After,

  $ perf list --raw-dump
  cpu-cycles instructions cache-references cache-misses ...
Signed-off-by: NTaesoo Kim <tsgatesv@gmail.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Taesoo kim <taesoo@gatech.edu>
Link: http://lkml.kernel.org/r/1419997015-11071-1-git-send-email-tsgatesv@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b3505208
  11. 02 1月, 2015 2 次提交
    • N
      perf probe: Fix crash in dwarf_getcfi_elf · 4093325f
      由 Namhyung Kim 提交于 
      David reported that perf can segfault when adding an uprobe event like
this:

  $ perf probe -x /lib64/libc-2.14.90.so -a 'malloc  size=%di'

  (gdb) bt
  #0  parse_eh_frame_hdr (hdr=0x0, hdr_size=2596, hdr_vaddr=71788,
      ehdr=0x7fffffffd390, eh_frame_vaddr=
      0x7fffffffd378, table_entries=0x8808d8, table_encoding=0x8808e0 "") at
      dwarf_getcfi_elf.c:79
  #1  0x000000385f81615a in getcfi_scn_eh_frame (hdr_vaddr=71788,
      hdr_scn=0x8839b0, shdr=0x7fffffffd2f0, scn=<optimized out>,
      ehdr=0x7fffffffd390, elf=0x882b30) at dwarf_getcfi_elf.c:231
  #2  getcfi_shdr (ehdr=0x7fffffffd390, elf=0x882b30) at dwarf_getcfi_elf.c:283
  #3  dwarf_getcfi_elf (elf=0x882b30) at dwarf_getcfi_elf.c:309
  #4  0x00000000004d5bac in debuginfo__find_probes (pf=0x7fffffffd4f0,
      dbg=Unhandled dwarf expression opcode 0xfa) at util/probe-finder.c:993
  #5  0x00000000004d634a in debuginfo__find_trace_events (dbg=0x880840,
      pev=<optimized out>, tevs=0x880f88, max_tevs=<optimized out>) at
      util/probe-finder.c:1200
  #6  0x00000000004aed6b in try_to_find_probe_trace_events (target=0x881b20
      "/lib64/libpthread-2.14.90.so",
      max_tevs=128, tevs=0x880f88, pev=0x859b30) at util/probe-event.c:482
  #7  convert_to_probe_trace_events (target=0x881b20
      "/lib64/libpthread-2.14.90.so", max_tevs=128, tevs=0x880f88,
      pev=0x859b30) at util/probe-event.c:2356
  #8  add_perf_probe_events (pevs=<optimized out>, npevs=1, max_tevs=128,
      target=0x881b20 "/lib64/libpthread-2.14.90.so", force_add=false) at
      util/probe-event.c:2391
  #9  0x000000000044014f in __cmd_probe (argc=<optimized out>,
      argv=0x7fffffffe2f0, prefix=Unhandled dwarf expression opcode 0xfa) at
      at builtin-probe.c:488
  #10 0x0000000000440313 in cmd_probe (argc=5, argv=0x7fffffffe2f0,
      prefix=<optimized out>) at builtin-probe.c:506
  #11 0x000000000041d133 in run_builtin (p=0x805680, argc=5,
      argv=0x7fffffffe2f0) at perf.c:341
  #12 0x000000000041c8b2 in handle_internal_command (argv=<optimized out>,
      argc=<optimized out>) at perf.c:400
  #13 run_argv (argv=<optimized out>, argcp=<optimized out>) at perf.c:444
  #14 main (argc=5, argv=0x7fffffffe2f0) at perf.c:559

And I found a related commit (5704c8c4fa71 "getcfi_scn_eh_frame: Don't
crash and burn when .eh_frame bits aren't there.") in elfutils that can
lead to a unexpected crash like this.  To safely use the function, it
needs to check the .eh_frame section is a PROGBITS type.
Reported-by: NDavid Ahern <dsahern@gmail.com>
Tested-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20141230090533.GH6081@sejongSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      4093325f
    • M
      perf probe: Fix to fall back to find probe point in symbols · 906451b9
      由 Masami Hiramatsu 提交于 
      Fix to fall back to find a probe point in symbols if perf fails to find
it in debuginfo.

This can happen when the target function is an alias of another
function. Such alias doesn't have an entry in debuginfo but in symbols.

David Ahern reported this problem in https://lkml.org/lkml/2014/12/29/355

I ensured the problem and deeper investigation discovers it.
 -----
 eu-readelf --debug-dump=info /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so | grep \"malloc\" -A6
             name                 (strp) "malloc"
             decl_file            (data1) 25
             decl_line            (data2) 466
             prototyped           (flag_present)
             type                 (ref4) [  81b5]
             declaration          (flag_present)
 [  8f58]      formal_parameter
 --
             name                 (strp) "malloc"
             decl_file            (data1) 23
             decl_line            (data2) 466
             prototyped           (flag_present)
             type                 (ref4) [  9f4a]
             declaration          (flag_present)
             sibling              (ref4) [  bb29]
 ...
 -----
All these entires have no instances (all of them are declarations)
This is why the perf probe failed to find it in debuginfo.

However, there are some malloc instances in symbols.
 -----
 eu-readelf --symbols /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so | grep malloc$
  1181: 0000000000080700   5332 FUNC    LOCAL  DEFAULT       12 _int_malloc
  4537: 00000000000831d0    339 FUNC    LOCAL  DEFAULT       12 __GI___libc_malloc
  5545: 00000000000831d0    339 FUNC    LOCAL  DEFAULT       12 __malloc
  6063: 00000000000831d0    339 FUNC    GLOBAL DEFAULT       12 malloc
  7302: 00000000000831d0    339 FUNC    GLOBAL DEFAULT       12 __libc_malloc
 -----
As you an see, malloc and __libc_malloc have same address, and actually
__libc_malloc has an entry in debuginfo. So you can set up a probe on
__libc_malloc.

To fix this problem shortly, perf probe simply falls back to find probe
point(malloc) in symbols if it is not found in debuginfo.
Reported-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20141231062747.2087.80961.stgit@localhost.localdomainSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      906451b9
  13. 23 12月, 2014 1 次提交