1. Mar 24, 2018
    • Arnaldo Carvalho de Melo's avatar
      perf annotate: Support jumping from one function to another · e4cc91b8
      Arnaldo Carvalho de Melo authored
      For instance:
      
        entry_SYSCALL_64  /lib/modules/4.16.0-rc5-00086-gdf09348f
      
      /build/vmlinux
          5.50 │     → callq  do_syscall_64
         14.56 │       mov    0x58(%rsp),%rcx
          7.44 │       mov    0x80(%rsp),%r11
          0.32 │       cmp    %rcx,%r11
               │     → jne    swapgs_restore_regs_and_return_to_usermode
          0.32 │       shl    $0x10,%rcx
          0.32 │       sar    $0x10,%rcx
          3.24 │       cmp    %rcx,%r11
               │     → jne    swapgs_restore_regs_and_return_to_usermode
          2.27 │       cmpq   $0x33,0x88(%rsp)
          1.29 │     → jne    swapgs_restore_regs_and_return_to_usermode
               │       mov    0x30(%rsp),%r11
          8.74 │       cmp    %r11,0x90(%rsp)
               │     → jne    swapgs_restore_regs_and_return_to_usermode
          0.32 │       test   $0x10100,%r11
               │     → jne    swapgs_restore_regs_and_return_to_usermode
          0.32 │       cmpq   $0x2b,0xa0(%rsp)
          0.65 │     → jne    swapgs_restore_regs_and_return_to_usermode
      
      It'll behave just like a "call" instruction, i.e. press enter or right
      arrow over one such line and the browser will navigate to the annotated
      disassembly of that function, which when exited, via left arrow or esc,
      will come back to the calling function.
      
      Now to support jump to an offset on a different function...
      
      Reported-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Wang Nan <wangnan0@huawei.com>
      Link: https://lkml.kernel.org/n/tip-78o508mqvr8inhj63ddtw7mo@git.kernel.org
      
      
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      e4cc91b8
    • Arnaldo Carvalho de Melo's avatar
      perf annotate: Add "_local" to jump/offset validation routines · 2eff0611
      Arnaldo Carvalho de Melo authored
      Because they all really check if we can access data structures/visual
      constructs where a "jump" instruction targets code in the same function,
      i.e. things like:
      
        __pthread_mutex_lock  /usr/lib64/libpthread-2.26.so
        1.95 │       mov    __pthread_force_elision,%ecx
             │    ┌──test   %ecx,%ecx
        0.07 │    ├──je     60
             │    │  test   $0x300,%esi
             │    │↓ jne    60
             │    │  or     $0x100,%esi
             │    │  mov    %esi,0x10(%rdi)
             │ 42:│  mov    %esi,%edx
             │    │  lea    0x16(%r8),%rsi
             │    │  mov    %r8,%rdi
             │    │  and    $0x80,%edx
             │    │  add    $0x8,%rsp
             │    │→ jmpq   __lll_lock_elision
             │    │  nop
        0.29 │ 60:└─→and    $0x80,%esi
        0.07 │       mov    $0x1,%edi
        0.29 │       xor    %eax,%eax
        2.53 │       lock   cmpxchg %edi,(%r8)
      
      And not things like that "jmpq __lll_lock_elision", that instead should behave
      like a "call" instruction and "jump" to the disassembly of "___lll_lock_elision".
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Wang Nan <wangnan0@huawei.com>
      Link: https://lkml.kernel.org/n/tip-3cwx39u3h66dfw9xjrlt7ca2@git.kernel.org
      
      
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      2eff0611
    • Petr Machata's avatar
      perf python: Reference Py_None before returning it · 83428f2f
      Petr Machata authored
      
      
      Python None objects are handled just like all the other objects with
      respect to their reference counting. Before returning Py_None, its
      reference count thus needs to be bumped.
      
      Signed-off-by: default avatarPetr Machata <petrm@mellanox.com>
      Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Petr Machata <petrm@mellanox.com>
      Link: http://lkml.kernel.org/r/b1e565ecccf68064d8d54f37db5d028dda8fa522.1521675563.git.petrm@mellanox.com
      
      
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      83428f2f
  2. Mar 22, 2018
  3. Mar 21, 2018