Allow enabling ibs op micro-ops counting mode.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333390758-10893-4-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

We always need to pass the last sample period to
perf_sample_data_init(), otherwise the event distribution will be
wrong. Thus, modifiyng the function interface with the required period
as argument. So basically a pattern like this:

        perf_sample_data_init(&data, ~0ULL);
        data.period = event->hw.last_period;

will now be like that:

        perf_sample_data_init(&data, ~0ULL, event->hw.last_period);

Avoids unininitialized data.period and simplifies code.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333390758-10893-3-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

The last sw period was not correctly updated on overflow and thus led
to wrong distribution of events. We always need to properly initialize
data.period in struct perf_sample_data.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333390758-10893-2-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

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: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Just suppress the nop operands, future infrastructure that will record
the instruction lenght (and its contents) in struct ins will allow
rendering them as nopN, i.e. nop5 for a 5-byte nop.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-qddbeglfzqdlal8vj2yaj67y@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Instead of doing the same in all ins scnprintf methods.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-8mfairi2n1nentoa852alazv@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge branch 'tip/perf/core-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

If CONFIG_KPROBES is not set, then linux/kprobes.h will not include
asm/kprobes.h needed by x86/ftrace.c for the BREAKPOINT macro.

The x86/ftrace.c file should just include asm/kprobes.h as it does not
need the rest of kprobes.
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Gets confusing. Remains to be chosen an appropriate different color for
source code.

This effectively reverts 58e817d9 ("perf annotate: Print asm code as
blue when source code is displayed")
Requested-by: Peter Zijlstra <peterz@infradead.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-qy9iq32nj3uqe5dbiuq9e3j9@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The first column (columns in the near future) are for the per line event
overhead(s), that only appear when they are not zero.

To clearly separate it, add back a solid vertical line, with just one
colour, not influenced by the per line overheads.

Then have the addr/offset column, then optionally the dynamic
(static in the future) jump->target arrows, if 'j' enables it.

Then the instructions.
Requested-by: Peter Zijlstra <peterz@infradead.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-r415t4sps0oyr9y8kd9j7clz@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-umb4jlu0ee8r2rc3x4jkahgk@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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: Steven Rostedt <rostedt@goodmis.org>

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: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Cleaning up more the output.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-81pimnsnaa9y2j0a9plstu1c@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It is confusing when used with jump -> target lines.
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-xeiyfsxptwtmlvowledg6wpy@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Instead of trying to show the current loop by naively looking for the
next backward jump, just use 'j' to toggle showing arrows connecting
jump with its target.

And do it for forward jumps as well.

Loop detection requires more code to follow the flow control, etc.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-soahcn1lz2u4wxj31ch0594j@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It figures out the direction and draws downwards arrows too if that is
the case.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-tg329nr7q4dg9d0tl3o0wywg@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The counterpart of 'ret' instructions.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-jlz2ldaquaow0rqi2vr4b91l@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-annotate-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Annotation improvements:

Now the default annotate browser uses a much more compact format, implementing
suggestions made made by several people, notably Linus.

Here is part of the new __list_del_entry() annotation:

__list_del_entry
    8.47 │      push   %rbp
    8.47 │      mov    (%rdi),%rdx
   20.34 │      mov    $0xdead000000100100,%rcx
    3.39 │      mov    0x8(%rdi),%rax
    0.00 │      mov    %rsp,%rbp
    1.69 │      cmp    %rcx,%rdx
    0.00 │      je     43
    1.69 │      mov    $0xdead000000200200,%rcx
    3.39 │      cmp    %rcx,%rax
    0.00 │      je     a3
    5.08 │      mov    (%rax),%r8
   18.64 │      cmp    %r8,%rdi
    0.00 │      jne    84
    1.69 │      mov    0x8(%rdx),%r8
   25.42 │      cmp    %r8,%rdi
    0.00 │      jne    65
    1.69 │      mov    %rax,0x8(%rdx)
    0.00 │      mov    %rdx,(%rax)
    0.00 │      leaveq
    0.00 │      retq
    0.00 │ 43:  mov    %rdx,%r8
    0.00 │      mov    %rdi,%rcx
    0.00 │      mov    $0xffffffff817cd6a8,%rdx
    0.00 │      mov    $0x31,%esi
    0.00 │      mov    $0xffffffff817cd6e0,%rdi
    0.00 │      xor    %eax,%eax
    0.00 │      callq  ffffffff8104eab0 <warn_slowpath_fmt>
    0.00 │      leaveq
    0.00 │      retq
    0.00 │ 65:  mov    %rdi,%rcx
    0.00 │      mov    $0xffffffff817cd780,%rdx
    0.00 │      mov    $0x3a,%esi
    0.00 │      mov    $0xffffffff817cd6e0,%rdi
    0.00 │      xor    %eax,%eax
    0.00 │      callq  ffffffff8104eab0 <warn_slowpath_fmt>
    0.00 │      leaveq
    0.00 │      retq

The infrastructure is there to provide formatters for any instruction,
like the one I'll do for call functions to elide the address.

Further fixes on top of the first iteration:

- Sometimes a jump points to an offset with no instructions, make the
  mark jump targets function handle that, for now just ignoring such
  jump targets, more investigation is needed to figure out how to cope
  with that.

- Handle jump targets that are outside the function, for now just don't
  try to draw the connector arrow, right thing seems to be to mark this
  jump with a -> (right arrow) and handle it like a callq.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Renaming remaining PERF_COUNTERS options into PERF_EVENTS.

Think we can get rid of PERF_COUNTERS now.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333643084-26776-5-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

No need to have an additional function layer.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333643084-26776-4-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Now the return value of cmpxchg() is used to match an event. The
change removes the duplicate event comparison and traverses the list
until an event was removed. This also fixes the following warning:

 arch/x86/kernel/cpu/perf_event_amd.c:170: warning: value computed is not used
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333643084-26776-3-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Removing duplicate code.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333643084-26776-2-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

As described in the previous patch. Next step is to properly label those
jumps by using a -> arrow, i.e. not backwards/forwards, and allow the
user to navigate to this other function when enter or -> is pressed.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-ax2sss463eu88wgl9ee8a6b6@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

I.e. jumps that go to code outside the current function, that is denoted
in objdump -dS as:

   399f877a9f: jne    399f87bcf4 <_L_lock_5154>

I.e. without the + after the name of the current function, like in:

   399f877aa5: jmp    399f877ab2 <_int_free+0x412>

The browser will use that info to avoid drawing connectors to the start
of the function, since ops.target.addr was zero.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-xrn35g2mlawz1ydo1p73w3q6@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We were using ins_ops->target for callq addresses and jump offsets,
disambiguate by having ins_ops->target.addr and ins_ops->target.offset.

For jumps we'll need both to fixup lines that don't have an offset on
the <> part.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-3nlcmstua75u07ao7wja1rwx@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

A function name represents the pointer to it - no need to take the
address of it. (Fixing this helps us introduce some macro magic
around register_nmi_handler() in the future.)

Cc: Robert Richter <robert.richter@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

In annotate_browser__mark_jump_targets

702                     dlt = browser->offsets[dl->ops.target];
703                     bdlt = disasm_line__browser(dlt);
704                     bdlt->jump_target = true;
705             }
706
707     }

(gdb) p size
$5 = 2415
(gdb) p offset
$6 = 140
(gdb) p dl->ops.target
$7 = 143
(gdb) p browser->offsets[143]
$8 = (struct disasm_line *) 0x0
(gdb) p dl->name
$9 = 0x2363bd0 "je"
(gdb)

Really strange, the code assumed that at the jump target we would have
an assembly line, but only in the previous instruction offset we have a
'lock':

(gdb) p browser->offsets[144]
$10 = (struct disasm_line *) 0x0
(gdb) p browser->offsets[142]
$11 = (struct disasm_line *) 0x27bd620
(gdb) p browser->offsets[142]->name
$12 = 0x237a8a0 "lock"
(gdb)

I'll study this more, but for now I'll just check if there is a
disasm_line at dl->ops.target, i.e. a valid jump target.
Reported-by: Hagen Paul Pfeifer <hagen@jauu.net>
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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-inzjrzyqhkzyv78met2vula6@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge v3.4-rc4 - we were on -rc2 before.
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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: Linus 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: Arnaldo Carvalho de Melo <acme@redhat.com>

Add a debugfs entry under per_cpu/ folder for each cpu called
buffer_size_kb to control the ring buffer size for each CPU
independently.

If the global file buffer_size_kb is used to set size, the individual
ring buffers will be adjusted to the given size. The buffer_size_kb will
report the common size to maintain backward compatibility.

If the buffer_size_kb file under the per_cpu/ directory is used to
change buffer size for a specific CPU, only the size of the respective
ring buffer is updated. When tracing/buffer_size_kb is read, it reports
'X' to indicate that sizes of per_cpu ring buffers are not equivalent.

Link: http://lkml.kernel.org/r/1328212844-11889-1-git-send-email-vnagarnaik@google.com

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: Justin Teravest <teravest@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

memcpy() returns a pointer to "bug".  Hopefully, it's not NULL here or
we would already have Oopsed.

Link: http://lkml.kernel.org/r/20120420063145.GA22649@elgon.mountain

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Currently, trace_printk() uses a single buffer to write into
to calculate the size and format needed to save the trace. To
do this safely in an SMP environment, a spin_lock() is taken
to only allow one writer at a time to the buffer. But this could
also affect what is being traced, and add synchronization that
would not be there otherwise.

Ideally, using percpu buffers would be useful, but since trace_printk()
is only used in development, having per cpu buffers for something
never used is a waste of space. Thus, the use of the trace_bprintk()
format section is changed to be used for static fmts as well as dynamic ones.
Then at boot up, we can check if the section that holds the trace_printk
formats is non-empty, and if it does contain something, then we
know a trace_printk() has been added to the kernel. At this time
the trace_printk per cpu buffers are allocated. A check is also
done at module load time in case a module is added that contains a
trace_printk().

Once the buffers are allocated, they are never freed. If you use
a trace_printk() then you should know what you are doing.

A buffer is made for each type of context:

  normal
  softirq
  irq
  nmi

The context is checked and the appropriate buffer is used.
This allows for totally lockless usage of trace_printk(),
and they no longer even disable interrupts.
Requested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Otherwise cpu_active_mask will not set, which lead to other issue.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Signed-off-by: Konrad Eisele <konrad@gaisler.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull "ARM: SoC fixes" from Olof Johansson:
 * at91, ux500, imx, omap and bcmring:
  - at91 fixes for =m driver build issues, irqdomain fixes and config
    dependency fixes
  - ux500 kconfig dependency fixes and a  smp wakeup bugfix
  - imx idle bugfix and build fix due to irq domain changes
  - omap uart pinmux fixes, softreset regression revert and misc fixes
  - bcmring build error regression fix

 * ux500 and imx had some small defconfig updates in this branch

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (27 commits)
  ARM: bcmring: fix UART declarations
  ARM: imx: Fix imx5 idle logic bug
  ARM: imx27-dt: Fix build due to removal of irq_domain_add_simple()
  ARM: imx_v4_v5_defconfig: Add support for CONFIG_REGULATOR_FIXED_VOLTAGE
  ARM: OMAP1: DMTIMER: fix broken timer clock source selection
  ARM: OMAP: serial: Fix the ocp smart idlemode handling bug
  ARM: OMAP2+: UART: Fix incorrect population of default uart pads
  ARM: OMAP: sram: fix BUG in dpll code for !PM case
  dmaengine: Kconfig: fix Atmel at_hdmac entry
  USB: gadget/at91_udc: add gpio_to_irq() function to vbus interrupt
  USB: ohci-at91: change annotations for probe/remove functions
  leds-atmel-pwm.c: Make pwmled_probe() __devinit
  ARM: at91: fix at91sam9261ek Ethernet dm9000 irq
  ARM: at91: fix rm9200ek flash size
  ARM: at91: remove empty at91_init_serial function
  ARM: at91: fix typo in at91_pmc_base assembly declaration
  ARM: at91: Export at91_matrix_base
  ARM: at91: Export at91_pmc_base
  ARM: at91: Export at91_ramc_base
  ARM: at91: Export at91_st_base
  ...

Pull MMC fixes from Chris Ball:
 - Build fix for omap_hsmmc with OF against 3.4-rc1.
 - Fix CONFIG_MMC_UNSAFE_RESUME semantics regression against 3.3, which
   broke hotplug card detection when UNSAFE_RESUME is set.
 - Fix a race condition in omap_hsmmc with runtime PM.
 - Fix two libertas SDIO-powered-resume regressions.
 - Small fixes for discard/sanitize, dw_mmc, cd-gpio and esdhc-imx.

* tag 'mmc-fixes-for-3.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
  mmc: core: Do not pre-claim host in suspend
  mmc: dw_mmc: prevent NULL dereference for dma_ops
  mmc: unbreak sdhci-esdhc-imx on i.MX25
  mmc: cd-gpio: Include header to pickup exported symbol prototypes
  mmc: sdhci: refine non-removable card checking for card detection
  mmc: dw_mmc: Fix switch from DMA to PIO
  mmc: remove MMC bus legacy suspend/resume method
  mmc: omap_hsmmc: Get rid of of_have_populated_dt() usage
  mmc: omap_hsmmc: build fix for CONFIG_OF=y and CONFIG_MMC_OMAP_HS=m
  mmc: fixes for eMMC v4.5 sanitize operation
  mmc: fixes for eMMC v4.5 discard operation

Pull media fixes from Mauro Carvalho Chehab:
 - Fixes a regression at DVB core when switching from DVB-S2 to DVB-S on
   Kaffeine (Fedora 16 Bugzilla #812895);
 - Fixes a mutex unlock at an error condition at drx-k;
 - Fix winbond-cir set mode;
 - mt9m032: Fix a compilation breakage with some random Kconfig;
 - mt9m032: fix two dead locks;
 - xc5000: don't require an special firmware (that won't be provided by
   the vendor) just because the xtal frequency is different;
 - V4L DocBook: fix some typos at multi-plane formats description.

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] xc5000: support 32MHz & 31.875MHz xtal using the 41.024.5 firmware
  [media] V4L: mt9m032: fix compilation breakage
  [media] V4L: DocBook: Fix typos in the multi-plane formats description
  [media] V4L: mt9m032: fix two dead-locks
  [media] rc-core: set mode for winbond-cir
  [media] drxk: Does not unlock mutex if sanity check failed in scu_command()
  [media] dvb_frontend: Fix a regression when switching back to DVB-S

Pull MFD fixes from Samuel Ortiz:
 "We have 3 build fixes, a OMAP USB host PHY reset fix and the twl6040
  conversion to an i2c driver.  The latter may not sound like a fix but
  the twl6040 MFD driver won't probe without it, triggering an OMAP4
  audio regression."

* tag 'mfd-for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
  mfd: Fix modular builds of rc5t583 regulator support
  mfd: Fix asic3_gpio_to_irq
  ARM: OMAP3: USB: Fix the EHCI ULPI PHY reset issue
  mfd: Convert twl6040 to i2c driver, and separate it from twl core
  mfd : Fix dbx500 compilation error