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  1. 09 May, 2012 13 commits
  3. 08 May, 2012 1 commit
    • Ingo Molnar's avatar
      Merge branch 'perf/annotate' of... · 149936a0
      Ingo Molnar authored 
      Merge branch 'perf/annotate' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Perf annotate browser improvements:

 - Get back the line separating the overheads from the disassembly, requested by
   Peter Zijlstra, Linus agreed now that it is a solid line and more column real
   state was harvested. Also it has the jump->arrow lines separated from it by
   the address/jump target column.

 - Don't change asm line color when toggling source code view. Requested by
   Peter Zijlstra.

Current snapshot:

 avtab_search_node
        │      push   %rbp
        │      mov    %rsp,%rbp
        │    → callq  mcount
        │      movzwl 0x6(%rsi),%edx
        │      and    $0x7fff,%dx
        │      test   %rdi,%rdi
        │    ↓ jne    20
   0.42 │17:┌─→xor    %eax,%eax
        │19:│  leaveq
   0.42 │   │← retq
        │   │  nopl   0x0(%rax,%rax,1)
        │20:│  mov    (%rdi),%rax
   0.08 │   │  test   %rax,%rax
        │   └──je     17
        │      movzwl (%rsi),%ecx
        │      movzwl 0x2(%rsi),%r9d
        │      movzwl 0x4(%rsi),%r8d
        │      movzwl %cx,%esi
        │      movzwl %r9w,%r10d
        │      shl    $0x9,%esi
        │      lea    (%rsi,%r10,4),%esi
        │      lea    (%r8,%rsi,1),%esi
        │      and    0x10(%rdi),%si
        │      movzwl %si,%esi
        │      mov    (%rax,%rsi,8),%rax
   1.01 │      test   %rax,%rax
        │    ↑ je     19
        │      nopw   0x0(%rax,%rax,1)
   3.19 │60:   cmp    %cx,(%rax)
        │    ↓ jne    7e
   0.08 │      cmp    %r9w,0x2(%rax)
        │    ↓ jne    7e
        │      cmp    %r8w,0x4(%rax)
        │    ↓ jne    79
        │      test   %dx,0x6(%rax)
        │    ↑ jne    19
        │79:   cmp    %r8w,0x4(%rax)
  83.45 │7e: ↑ ja     17
   3.36 │      mov    0x10(%rax),%rax
   7.98 │      test   %rax,%rax
        │    ↑ jne    60
        │      leaveq
        │    ← retq
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      149936a0
  5. 07 May, 2012 3 commits
  7. 04 May, 2012 1 commit
  9. 03 May, 2012 3 commits
  11. 28 Apr, 2012 2 commits
    • Steven Rostedt's avatar
      ftrace/x86: Remove the complex ftrace NMI handling code · 4a6d70c9
      Steven Rostedt authored 
      As ftrace function tracing would require modifying code that could
be executed in NMI context, which is not stopped with stop_machine(),
ftrace had to do a complex algorithm with various stages of setup
and memory barriers to make it work.

With the new breakpoint method, this is no longer required. The changes
to the code can be done without any problem in NMI context, as well as
without stop machine altogether. Remove the complex code as it is
no longer needed.

Also, a lot of the notrace annotations could be removed from the
NMI code as it is now safe to trace them. With the exception of
do_nmi itself, which does some special work to handle running in
the debug stack. The breakpoint method can cause NMIs to double
nest the debug stack if it's not setup properly, and that is done
in do_nmi(), thus that function must not be traced.

(Note the arch sh may want to do the same)

Cc: Paul Mundt <lethal@linux-sh.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      4a6d70c9
    • Steven Rostedt's avatar
      ftrace/x86: Have arch x86_64 use breakpoints instead of stop machine · 08d636b6
      Steven Rostedt authored 
      This method changes x86 to add a breakpoint to the mcount locations
instead of calling stop machine.

Now that iret can be handled by NMIs, we perform the following to
update code:

1) Add a breakpoint to all locations that will be modified

2) Sync all cores

3) Update all locations to be either a nop or call (except breakpoint
   op)

4) Sync all cores

5) Remove the breakpoint with the new code.

6) Sync all cores

[
  Added updates that Masami suggested:
   Use unlikely(modifying_ftrace_code) in int3 trap to keep kprobes efficient.
   Don't use NOTIFY_* in ftrace handler in int3 as it is not a notifier.
]

Cc: H. Peter Anvin <hpa@zytor.com>
Acked-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      08d636b6
  13. 27 Apr, 2012 6 commits
  15. 26 Apr, 2012 4 commits
  17. 25 Apr, 2012 6 commits
  19. 24 Apr, 2012 1 commit
    • Arnaldo Carvalho de Melo's avatar
      perf annotate browser: Initial loop detection · a3f895be
      Arnaldo Carvalho de Melo authored 
      Simple algorithm, just look for the next backward jump that points to
before the cursor.

Then draw an arrow connecting the jump to its target.

Do this as you move the cursor, entering/exiting possible loops.

Ex (graph chars replaced to avoid mail encoding woes):

avc_has_perm_flags
    0.00 |         nopl   0x0(%rax)
    5.36 |+-> 68:  mov    (%rax),%rax
    5.15 ||        test   %rax,%rax
    0.00 ||      v je     130
    2.96 ||   74:  cmp    -0x20(%rax),%ebx
   47.38 ||        lea    -0x20(%rax),%rcx
    0.28 ||      ^ jne    68
    3.16 ||        cmp    -0x18(%rax),%dx
    0.00 |+------^ jne    68
    4.92 |         cmp    0x4(%rcx),%r13d
    0.00 |       v jne    68
    1.15 |         test   %rcx,%rcx
    0.00 |       v je     130
Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
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-5gairf6or7dazlx3ocxwvftm@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      a3f895be
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