linux-toradex.git/arch/x86/kernel/alternative.c, branch v3.2

x86: Call stop_machine_text_poke() on all CPUs

2011-11-14T12:05:15+00:00

It appears that stop_machine_text_poke() wants to be called on all CPUs,
like it's done from text_poke_smp().  Fix text_poke_smp_batch() to do
this.

Signed-off-by: Rabin Vincent 
Acked-by: Masami Hiramatsu 
Signed-off-by: Peter Zijlstra 
Cc: Mathieu Desnoyers 
Cc: Jason Baron 
Link: http://lkml.kernel.org/r/1319702072-32676-1-git-send-email-rabin@rab.in
Signed-off-by: Ingo Molnar

x86-64: Move vread_tsc and vread_hpet into the vDSO

2011-07-15T00:57:05+00:00

The vsyscall page now consists entirely of trap instructions.

Cc: John Stultz 
Signed-off-by: Andy Lutomirski 
Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu
Signed-off-by: H. Peter Anvin

x86: Make alternative instruction pointers relative

2011-07-13T18:22:56+00:00

This save a few bytes on x86-64 and means that future patches can
apply alternatives to unrelocated code.

Signed-off-by: Andy Lutomirski 
Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin

Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2011-05-20T00:55:12+00:00

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, cpu: Fix detection of Celeron Covington stepping A1 and B0
  Documentation, ABI: Update L3 cache index disable text
  x86, AMD, cacheinfo: Fix L3 cache index disable checks
  x86, AMD, cacheinfo: Fix fallout caused by max3 conversion
  x86, cpu: Change NOP selection for certain Intel CPUs
  x86, cpu: Clean up and unify the NOP selection infrastructure
  x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4
  x86, cpu: Move AMD Elan Kconfig under "Processor family"

Fix up trivial conflicts in alternative handling (commit dc326fca2b64
"x86, cpu: Clean up and unify the NOP selection infrastructure" removed
some hacky 5-byte instruction stuff, while commit d430d3d7e646 "jump
label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to
CONFIG_JUMP_LABEL in the code that went away)

Merge branch 'x86/mem' into perf/core

2011-05-18T18:59:30+00:00

Merge reason: memcpy_64.S changes an assumption perf bench has, so merge this
              here so we can fix it.

Signed-off-by: Ingo Molnar

x86, alternative, doc: Add comment for applying alternatives order

2011-05-17T22:40:25+00:00

Some string operation functions may be patched twice, e.g. on enhanced REP MOVSB
/STOSB processors, memcpy is patched first by fast string alternative function,
then it is patched by enhanced REP MOVSB/STOSB alternative function.

Add comment for applying alternatives order to warn people who may change the
applying alternatives order for any reason.

[ Documentation-only patch ]

Signed-off-by: Fenghua Yu 
Link: http://lkml.kernel.org/r/1305671358-14478-4-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin

x86, cpu: Change NOP selection for certain Intel CPUs

2011-04-18T23:40:32+00:00

Due to a decoder implementation quirk, some specific Intel CPUs
actually perform better with the "k8_nops" than with the
SDM-recommended NOPs.  For runtime-selected NOPs, if we detect those
specific CPUs then use the k8_nops instead of the ones we would
normally use.

Signed-off-by: H. Peter Anvin 
Cc: Tejun Heo 
Cc: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Jason Baron 
Link: http://lkml.kernel.org/r/1303166160-10315-4-git-send-email-hpa@linux.intel.com

x86, cpu: Clean up and unify the NOP selection infrastructure

2011-04-18T23:40:21+00:00

Clean up and unify the NOP selection infrastructure:

- Make the atomic 5-byte NOP a part of the selection system.
- Pick NOPs once during early boot and then be done with it.

Signed-off-by: H. Peter Anvin 
Cc: Tejun Heo 
Cc: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Jason Baron 
Link: http://lkml.kernel.org/r/1303166160-10315-3-git-send-email-hpa@linux.intel.com

jump label: Introduce static_branch() interface

2011-04-04T16:48:08+00:00

Introduce:

static __always_inline bool static_branch(struct jump_label_key *key);

instead of the old JUMP_LABEL(key, label) macro.

In this way, jump labels become really easy to use:

Define:

        struct jump_label_key jump_key;

Can be used as:

        if (static_branch(&jump_key))
                do unlikely code

enable/disale via:

        jump_label_inc(&jump_key);
        jump_label_dec(&jump_key);

that's it!

For the jump labels disabled case, the static_branch() becomes an
atomic_read(), and jump_label_inc()/dec() are simply atomic_inc(),
atomic_dec() operations. We show testing results for this change below.

Thanks to H. Peter Anvin for suggesting the 'static_branch()' construct.

Since we now require a 'struct jump_label_key *key', we can store a pointer into
the jump table addresses. In this way, we can enable/disable jump labels, in
basically constant time. This change allows us to completely remove the previous
hashtable scheme. Thanks to Peter Zijlstra for this re-write.

Testing:

I ran a series of 'tbench 20' runs 5 times (with reboots) for 3
configurations, where tracepoints were disabled.

jump label configured in
avg: 815.6

jump label *not* configured in (using atomic reads)
avg: 800.1

jump label *not* configured in (regular reads)
avg: 803.4

Signed-off-by: Peter Zijlstra 
LKML-Reference: <20110316212947.GA8792@redhat.com>
Signed-off-by: Jason Baron 
Suggested-by: H. Peter Anvin 
Tested-by: David Daney 
Acked-by: Ralf Baechle 
Acked-by: David S. Miller 
Acked-by: Mathieu Desnoyers 
Signed-off-by: Steven Rostedt

x86: Fix common misspellings

2011-03-18T09:39:30+00:00

They were generated by 'codespell' and then manually reviewed.

Signed-off-by: Lucas De Marchi 
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: Ingo Molnar