Commit Graph

12 Commits

Author SHA1 Message Date
Jaswinder Singh Rajput 8fa62ad9d2 x86: msr.h linux/types.h is only required for __KERNEL__
<linux/types.h> is only required for __KERNEL__ as whole file is covered with it

Also fixed some spacing issues for usr/include/asm-x86/msr.h

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: "H. Peter Anvin" <hpa@kernel.org>
LKML-Reference: <1245228070.2662.1.camel@ht.satnam>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-17 18:56:01 +02:00
Borislav Petkov b034c19f9f x86: MSR: add methods for writing of an MSR on several CPUs
Provide for concurrent MSR writes on all the CPUs in the cpumask. Also,
add a temporary workaround for smp_call_function_many which skips the
CPU we're executing on.

Bart: zero out rv struct which is allocated on stack.

CC: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-10 12:18:43 +02:00
Borislav Petkov 6bc1096d7a x86: MSR: add a struct representation of an MSR
Add a struct representing a 64bit MSR pair consisting of a low and high
register part and convert msr_info to use it. Also, rename msr-on-cpu.c
to msr.c.

Side note: Put the cpumask.h include in __KERNEL__ space thus fixing an
allmodconfig build failure in the headers_check target.

CC: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
2009-06-10 12:18:42 +02:00
Linus Torvalds b0f4b285d7 Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits)
  sched, trace: update trace_sched_wakeup()
  tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3
  Revert "x86: disable X86_PTRACE_BTS"
  ring-buffer: prevent false positive warning
  ring-buffer: fix dangling commit race
  ftrace: enable format arguments checking
  x86, bts: memory accounting
  x86, bts: add fork and exit handling
  ftrace: introduce tracing_reset_online_cpus() helper
  tracing: fix warnings in kernel/trace/trace_sched_switch.c
  tracing: fix warning in kernel/trace/trace.c
  tracing/ring-buffer: remove unused ring_buffer size
  trace: fix task state printout
  ftrace: add not to regex on filtering functions
  trace: better use of stack_trace_enabled for boot up code
  trace: add a way to enable or disable the stack tracer
  x86: entry_64 - introduce FTRACE_ frame macro v2
  tracing/ftrace: add the printk-msg-only option
  tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()
  x86, bts: correctly report invalid bts records
  ...

Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits
being already partly merged by the SH merge.
2008-12-28 12:21:10 -08:00
Frederic Weisbecker 0ca59dd948 tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3
Impact: fix a crash/hard-reboot on certain configs while enabling cpu runtime

On some archs, the boot of a secondary cpu can have an early fragile state.
On x86-64, the pda is not initialized on the first stage of a cpu boot but
it is needed to get the cpu number and the current task pointer. This data
is needed during tracing. As they were dereferenced at this stage, we got a
crash while tracing a cpu being enabled at runtime.

Some other archs like ia64 can have such kind of issue too.

Changes on v2:

We dropped the previous solution of a per-arch called function to guess the
current state of a cpu. That could slow down the tracing.

This patch removes the -pg flag on arch/x86/kernel/cpu/common.c where
the low level cpu boot functions exist, on start_secondary() and a helper
function used at this stage.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-25 09:39:22 +01:00
Ingo Molnar fa623d1b02 Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core 2008-12-23 16:27:23 +01:00
Ingo Molnar 78f902ccc5 Merge commit 'v2.6.28-rc8' into x86/doc 2008-12-16 22:04:48 +01:00
Ken Chen 205516c12d x86: convert rdtscll() to use __native_read_tsc
Impact: micro-optimization

Is there any reason why x86 rdtscll have to use the out of line
function instead of inline __native_read_tsc()?  native_read_tsc and
__native_read_tsc is essentially the same functions.

Patch to let x86 rdtscll() to use the inline version of read_tsc.

Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 10:17:02 +01:00
Ingo Molnar 0d12cdd5f8 sched: improve sched_clock() performance
in scheduler-intense workloads native_read_tsc() overhead accounts for
20% of the system overhead:

 659567 system_call                              41222.9375
 686796 schedule                                 435.7843
 718382 __switch_to                              665.1685
 823875 switch_mm                                4526.7857
 1883122 native_read_tsc                          55385.9412
 9761990 total                                      2.8468

this is large part due to the rdtsc_barrier() that is done before
and after reading the TSC.

But sched_clock() is not a precise clock in the GTOD sense, using such
barriers is completely pointless. So remove the barriers and only use
them in vget_cycles().

This improves lat_ctx performance by about 5%.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-08 16:48:19 +01:00
Jike Song d4f1b10365 x86: clean up comments wrt. rd{msr|tsc|pmc}
The rdmsr instruction(et al) for i386 and x86-64 are semantically same.
The only difference is how gcc interpret constraint "A" for these targets.

Signed-off-by: Jike Song <albcamus@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-28 16:47:08 +01:00
H. Peter Anvin 1965aae3c9 x86: Fix ASM_X86__ header guards
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:23 -07:00
Al Viro bb8985586b x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:20 -07:00