Commit Graph

83 Commits

Author SHA1 Message Date
Ingo Molnar
0afe2db213 Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-D
Conflicts:
	arch/x86/kernel/cpu/common.c
	arch/x86/kernel/signal_64.c
	include/asm-x86/cpufeature.h
2008-10-11 20:23:20 +02:00
Andi Kleen
fb481dd56a x86: drop -funroll-loops for csum_partial_64.c
Impact: performance optimization

I did some rebenchmarking with modern compilers and dropping
-funroll-loops makes the function consistently go faster by a few
percent.  So drop that flag.

Thanks to Richard Guenther for a hint.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-09-04 08:42:06 -07:00
H. Peter Anvin
b30a72a7ed Merge branch 'x86/urgent' into x86/cpu
Conflicts:

	arch/x86/kernel/cpu/cyrix.c
2008-08-27 19:17:07 -07:00
H. Peter Anvin
bdd314616f x86: msr-on-cpu: remove unnecessary level of abstraction
Remove an unnecessary level of abstraction in the msr-on-cpu library.
Although this duplicates some code, the duplicated code is less than
the additional code, and this way should be faster.

Additionally, change the order of the functions to make the regular
structure of this file more obvious.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-08-25 22:45:50 -07:00
H. Peter Anvin
94d4ac2f4a Merge branch 'x86/urgent' into x86/cleanups 2008-08-25 22:45:37 -07:00
H. Peter Anvin
c6f31932d0 x86: msr: propagate errors from smp_call_function_single()
Propagate error (-ENXIO) from smp_call_function_single().  These
errors can happen when a CPU is unplugged while the MSR driver is
open.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-08-25 17:45:48 -07:00
Thomas Petazzoni
8bfcb3960f x86: make movsl_mask definition non-CPU specific
movsl_mask is currently defined in arch/x86/kernel/cpu/intel.c, which
contains code specific to Intel CPUs. However, movsl_mask is used in
the non-CPU specific code in arch/x86/lib/usercopy_32.c, which breaks
the compilation when support for Intel CPUs is compiled out.

This patch solves this problem by moving movsl_mask's definition close
to its users in arch/x86/lib/usercopy_32.c.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: michael@free-electrons.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-18 16:05:45 +02:00
Paolo Ciarrocchi
3492cdf017 x86: coding style fixes to arch/x86/lib/string_32.c
Before:
total: 21 errors, 0 warnings, 237 lines checked

After:
total: 0 errors, 0 warnings, 237 lines checked

paolo@paolo-desktop:~/linux.trees.git$ md5sum /tmp/string_32.o.*
c55d059ef1612b32a8bb2771a72ae0d5  /tmp/string_32.o.after
c55d059ef1612b32a8bb2771a72ae0d5  /tmp/string_32.o.before

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 16:53:25 +02:00
Paolo Ciarrocchi
209b580fd8 x86: coding style fixes to arch/x86/lib/strstr_32.c
Before:
total: 3 errors, 0 warnings, 31 lines checked

After:
total: 0 errors, 0 warnings, 31 lines checked

paolo@paolo-desktop:~/linux.trees.git$ md5sum /tmp/strstr_32.o.*
c96006ec3387862e5bacb139207a3098  /tmp/strstr_32.o.after
c96006ec3387862e5bacb139207a3098  /tmp/strstr_32.o.before

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 16:53:24 +02:00
Vitaly Mayatskikh
afd962a9e8 x86: wrong register was used in align macro
New ALIGN_DESTINATION macro has sad typo: r8d register was used instead
of ecx in fixup section. This can be considered as a regression.

Register ecx was also wrongly loaded with value in r8d in
copy_user_nocache routine.

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-30 10:10:39 -07:00
Ingo Molnar
1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Ingo Molnar
5806b81ac1 Merge branch 'auto-ftrace-next' into tracing/for-linus
Conflicts:

	arch/x86/kernel/entry_32.S
	arch/x86/kernel/process_32.c
	arch/x86/kernel/process_64.c
	arch/x86/lib/Makefile
	include/asm-x86/irqflags.h
	kernel/Makefile
	kernel/sched.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 16:11:52 +02:00
Jeremy Fitzhardinge
27cb0a75ba x86: fix compile error in current tip.git
Gas 2.15 complains about 32-bit registers being used in lea.

  AS      arch/x86/lib/copy_user_64.o
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_64.S: Assembler messages:
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_64.S:188: Error: `(%edx,%ecx,8)' is not a valid 64 bit base/index expression
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_64.S:257: Error: `(%edx,%ecx,8)' is not a valid 64 bit base/index expression
  AS      arch/x86/lib/copy_user_nocache_64.o
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_nocache_64.S: Assembler messages:
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_nocache_64.S:107: Error: `(%edx,%ecx,8)' is not a valid 64 bit base/index expression

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-10 21:55:59 +02:00
Vitaly Mayatskikh
ad2fc2cd92 x86: fix copy_user on x86
Switch copy_user_generic_string(), copy_user_generic_unrolled() and
__copy_user_nocache() from custom tail handlers to generic
copy_user_tail_handle().

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 15:51:16 +02:00
Vitaly Mayatskikh
1129585a08 x86: introduce copy_user_handle_tail() routine
Introduce generic C routine for handling necessary tail operations after
protection fault in copy_*_user on x86.

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 15:51:03 +02:00
Glauber Costa
5cbbc3b1eb x86: merge putuser asm functions.
putuser_32.S and putuser_64.S are merged into putuser.S.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:13 +02:00
Glauber Costa
2528de431d x86: use macros from asm.h.
In putuser_32.S and putuser_64.S, replace things like .quad, .long,
and explicit references to [r|e]ax for the apropriate macros
in asm/asm.h.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:12 +02:00
Glauber Costa
efea505d83 x86: don't use word-size specifiers in putuser files.
Remove them where unambiguous.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:11 +02:00
Glauber Costa
766ed42821 x86: replace function headers by macros.
In putuser_64.S, do it the i386 way, and replace the code
in beginning and end of functions with macros, since it's
always the same thing. Save lines.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:10 +02:00
Glauber Costa
663aa96df3 x86: change testing logic in putuser_64.S.
Instead of operating over a register we need to put back
into normal state afterwards (the memory position), just
sub from rbx, which is trashed anyway. We can save a few instructions.

Also, this is the i386 way.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:09 +02:00
Glauber Costa
0ada316403 x86: pass argument to putuser_64 functions in ax register.
This is consistent with i386 usage.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:08 +02:00
Glauber Costa
770546b99f x86: clobber rbx in putuser_64.S.
Instead of clobbering r8, clobber rbx, which is the i386 way.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:08 +02:00
Glauber Costa
268cf048c8 x86: don't save ebx in putuser_32.S.
Clobber it in the inline asm macros, and let the compiler do this for us.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:06 +02:00
Glauber Costa
6c2d458680 x86: merge getuser asm functions.
getuser_32.S and getuser_64.S are merged into getuser.S.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:05 +02:00
Glauber Costa
87e2f1e7f6 x86: use _ASM_PTR instead of explicit word-size pointers.
Switch .long and .quad with _ASM_PTR in getuser*.S.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:04 +02:00
Glauber Costa
40faf463e6 x86: introduce __ASM_REG macro.
There are situations in which the architecture wants to use the
register that represents its word-size, whatever it is. For those,
introduce __ASM_REG in asm.h, along with the first users _ASM_AX
and _ASM_DX. They have users waiting for it, namely the getuser
functions.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:04 +02:00
Glauber Costa
ef8c1a2d0e x86: don't use word-size specifiers on getuser_64.
The instructions access registers, so the size is unambiguous.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:03 +02:00
Glauber Costa
26ccb8a718 x86: rename threadinfo to TI.
This is for consistency with i386.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:02 +02:00
Glauber Costa
9262875395 x86: adapt x86_64 getuser functions.
Instead of doing a sub after the addition, use the
offset directly at the memory operand of the mov instructions.
This is the way i386 do.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:01 +02:00
Glauber Costa
9aa038815b x86: don't use word-size specifiers.
Since the instructions refer to registers, they'll be able
to figure it out.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:14:00 +02:00
Glauber Costa
edf10162b2 x86: don't clobber r8 nor use rcx.
There's really no reason to clobber r8 or pass the address in rcx.
We can safely use only two registers (which we already have to touch anyway)
to do the job.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 09:13:59 +02:00
Glauber Costa
f0fbf0abc0 x86: integrate delay functions.
delay_32.c, delay_64.c are now equal, and are integrated into delay.c.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 08:52:05 +02:00
Glauber Costa
7e58818d32 x86: explicitly use edx in const delay function.
For x86_64, we can't just use %0, as it would
generate a mul against rdx, which is not really what we
want (note the ">> 32" in x86_64 version).

Using a u64 variable with a shift in i386 generates bad code,
so the solution is to explicitly use %%edx in inline assembly
for both.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 08:52:04 +02:00
Glauber Costa
a76febe975 x86: use rdtscll in read_current_timer for i386.
This way we achieve the same code for both arches.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 08:52:02 +02:00
Glauber Costa
0a4d8a472f x86: provide delay loop for x86_64.
This is for consistency with i386. We call use_tsc_delay()
at tsc initialization for x86_64, so we'll be always using it.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 08:51:41 +02:00
Glauber Costa
ff1b15b646 x86: don't use size specifiers.
Remove the "l" from inline asm at arch/x86/lib/delay_32.c.
It is not needed.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 08:49:27 +02:00
Jens Axboe
8691e5a8f6 smp_call_function: get rid of the unused nonatomic/retry argument
It's never used and the comments refer to nonatomic and retry
interchangably. So get rid of it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:35 +02:00
Ingo Molnar
28f73e51d0 Merge branch 'linus' into x86/delay
Conflicts:

	arch/x86/kernel/tsc_32.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-25 12:30:10 +02:00
Ingo Molnar
f34bfb1bee Merge branch 'linus' into tracing/ftrace 2008-06-23 11:11:42 +02:00
Linus Torvalds
42a886af72 x86-64: Fix "bytes left to copy" return value for copy_from_user()
Most users by far do not care about the exact return value (they only
really care about whether the copy succeeded in its entirety or not),
but a few special core routines actually care deeply about exactly how
many bytes were copied from user space.

And the unrolled versions of the x86-64 user copy routines would
sometimes report that it had copied more bytes than it actually had.

Very few uses actually have partial copies to begin with, but to make
this bug even harder to trigger, most x86 CPU's use the "rep string"
instructions for normal user copies, and that version didn't have this
issue.

To make it even harder to hit, the one user of this that really cared
about the return value (and used the uncached version of the copy that
doesn't use the "rep string" instructions) was the generic write
routine, which pre-populated its source, once more hiding the problem by
avoiding the exception case that triggers the bug.

In other words, very special thanks to Bron Gondwana who not only
triggered this, but created a test-program to show it, and bisected the
behavior down to commit 08291429cf ("mm:
fix pagecache write deadlocks") which changed the access pattern just
enough that you can now trigger it with 'writev()' with multiple
iovec's.

That commit itself was not the cause of the bug, it just allowed all the
stars to align just right that you could trigger the problem.

[ Side note: this is just the minimal fix to make the copy routines
  (with __copy_from_user_inatomic_nocache as the particular version that
  was involved in showing this) have the right return values.

  We really should improve on the exceptional case further - to make the
  copy do a byte-accurate copy up to the exact page limit that causes it
  to fail.  As it is, the callers have to do extra work to handle the
  limit case gracefully. ]

Reported-by: Bron Gondwana <brong@fastmail.fm>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

 (which didn't have this problem), and since
most users that do the carethis was very hard to trigger, but
2008-06-17 17:47:50 -07:00
Jiri Hladky
e01b70ef3e x86: fix bug in arch/i386/lib/delay.c file, delay_loop function
when trying to understand how Bogomips are implemented I have found a
bug in arch/i386/lib/delay.c file, delay_loop function.

The function fails for loops > 2^31+1. It because SF is set when dec
returns numbers > 2^31.

The fix is to use jnz instruction instead of jns (and add one decl
instruction to the end to have exactly the same number of loops as in
original version).

Martin Mares observed:

> It is a long time since I have hacked that file, but you should definitely
> make sure that the function is never called with a zero argument. In such
> case, the original version made just a single pass, but your version
> makes 2^32 of them.

fixed that.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-17 10:55:47 +02:00
Ingo Molnar
e765ee90da Merge branch 'linus' into tracing/ftrace 2008-06-16 11:15:58 +02:00
Steven Rostedt
5c1ea08215 x86: enable preemption in delay
The RT team has been searching for a nasty latency. This latency shows
up out of the blue and has been seen to be as big as 5ms!

Using ftrace I found the cause of the latency.

   pcscd-2995  3dNh1 52360300us : irq_exit (smp_apic_timer_interrupt)
   pcscd-2995  3dN.2 52360301us : idle_cpu (irq_exit)
   pcscd-2995  3dN.2 52360301us : rcu_irq_exit (irq_exit)
   pcscd-2995  3dN.1 52360771us : smp_apic_timer_interrupt (apic_timer_interrupt
)
   pcscd-2995  3dN.1 52360771us : exit_idle (smp_apic_timer_interrupt)

Here's an example of a 400 us latency. pcscd took a timer interrupt and
returned with "need resched" enabled, but did not reschedule until after
the next interrupt came in at 52360771us 400us later!

At first I thought we somehow missed a preemption check in entry.S. But
I also noticed that this always seemed to happen during a __delay call.

   pcscd-2995  3dN.2 52360836us : rcu_irq_exit (irq_exit)
   pcscd-2995  3.N.. 52361265us : preempt_schedule (__delay)

Looking at the x86 delay, I found my problem.

In git commit 35d5d08a08, Andrew Morton
placed preempt_disable around the entire delay due to TSC's not working
nicely on SMP.  Unfortunately for those that care about latencies this
is devastating! Especially when we have callers to mdelay(8).

Here I enable preemption during the loop and account for anytime the task
migrates to a new CPU. The delay asked for may be extended a bit by
the migration, but delay only guarantees that it will delay for that minimum
time. Delaying longer should not be an issue.

[
  Thanks to Thomas Gleixner for spotting that cpu wasn't updated,
    and to place the rep_nop between preempt_enabled/disable.
]

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: akpm@osdl.org
Cc: Clark Williams <clark.williams@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Luis Claudio R. Goncalves" <lclaudio@uudg.org>
Cc: Gregory Haskins <ghaskins@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andi Kleen <andi-suse@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-06-04 13:11:46 +02:00
Steven Rostedt
81d68a96a3 ftrace: trace irq disabled critical timings
This patch adds latency tracing for critical timings
(how long interrupts are disabled for).

 "irqsoff" is added to /debugfs/tracing/available_tracers

Note:
  tracing_max_latency
    also holds the max latency for irqsoff (in usecs).
   (default to large number so one must start latency tracing)

  tracing_thresh
    threshold (in usecs) to always print out if irqs off
    is detected to be longer than stated here.
    If irq_thresh is non-zero, then max_irq_latency
    is ignored.

Here's an example of a trace with ftrace_enabled = 0

=======
preemption latency trace v1.1.5 on 2.6.24-rc7
Signed-off-by: Ingo Molnar <mingo@elte.hu>
--------------------------------------------------------------------
 latency: 100 us, #3/3, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------
 => started at: _spin_lock_irqsave+0x2a/0xb7
 => ended at:   _spin_unlock_irqrestore+0x32/0x5f

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     1d.s3    0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
 swapper-0     1d.s3  100us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1d.s3  100us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)

vim:ft=help
=======

And this is a trace with ftrace_enabled == 1

=======
preemption latency trace v1.1.5 on 2.6.24-rc7
--------------------------------------------------------------------
 latency: 102 us, #12/12, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------
 => started at: _spin_lock_irqsave+0x2a/0xb7
 => ended at:   _spin_unlock_irqrestore+0x32/0x5f

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     1dNs3    0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
 swapper-0     1dNs3   46us : e1000_read_phy_reg+0x16/0x225 [e1000] (e1000_update_stats+0x5e2/0x64c [e1000])
 swapper-0     1dNs3   46us : e1000_swfw_sync_acquire+0x10/0x99 [e1000] (e1000_read_phy_reg+0x49/0x225 [e1000])
 swapper-0     1dNs3   46us : e1000_get_hw_eeprom_semaphore+0x12/0xa6 [e1000] (e1000_swfw_sync_acquire+0x36/0x99 [e1000])
 swapper-0     1dNs3   47us : __const_udelay+0x9/0x47 (e1000_read_phy_reg+0x116/0x225 [e1000])
 swapper-0     1dNs3   47us+: __delay+0x9/0x50 (__const_udelay+0x45/0x47)
 swapper-0     1dNs3   97us : preempt_schedule+0xc/0x84 (__delay+0x4e/0x50)
 swapper-0     1dNs3   98us : e1000_swfw_sync_release+0xc/0x55 [e1000] (e1000_read_phy_reg+0x211/0x225 [e1000])
 swapper-0     1dNs3   99us+: e1000_put_hw_eeprom_semaphore+0x9/0x35 [e1000] (e1000_swfw_sync_release+0x50/0x55 [e1000])
 swapper-0     1dNs3  101us : _spin_unlock_irqrestore+0xe/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1dNs3  102us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1dNs3  102us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)

vim:ft=help
=======

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:32:46 +02:00
Ingo Molnar
89804c022f x86: fix csum_partial() export
Fix this symbol export problem:

    Building modules, stage 2.
    MODPOST 193 modules
    ERROR: "csum_partial" [fs/reiserfs/reiserfs.ko] undefined!
    make[1]: *** [__modpost] Error 1
    make: *** [modules] Error 2

This is due to a known weakness of symbol exports: if a symbol's
only in-core user is an EXPORT_SYMBOL from a lib-y section, the
symbol is not linked in.

The solution is to move the export to x8664_ksyms_64.c - but the real
solution would be to fix kbuild.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-13 19:38:47 +02:00
Alexander van Heukelum
5245698f66 x86, UML: remove x86-specific implementations of find_first_bit
x86 has been switched to the generic versions of find_first_bit
and find_first_zero_bit, but the original versions were retained.
This patch just removes the now unused x86-specific versions.

also update UML.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:17 +02:00
Alexander van Heukelum
2aba6925fd x86: switch 64-bit to generic find_first_bit
Switch x86_64 to generic find_first_bit. The x86_64-specific
implementation is not removed.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Alexander van Heukelum
6fd92b63d0 x86: change x86 to use generic find_next_bit
The versions with inline assembly are in fact slower on the machines I
tested them on (in userspace) (Athlon XP 2800+, p4-like Xeon 2.8GHz, AMD
Opteron 270). The i386-version needed a fix similar to 06024f21 to avoid
crashing the benchmark.

Benchmark using: gcc -fomit-frame-pointer -Os. For each bitmap size
1...512, for each possible bitmap with one bit set, for each possible
offset: find the position of the first bit starting at offset. If you
follow ;). Times include setup of the bitmap and checking of the
results.

		Athlon		Xeon		Opteron 32/64bit
x86-specific:	0m3.692s	0m2.820s	0m3.196s / 0m2.480s
generic:	0m2.622s	0m1.662s	0m2.100s / 0m1.572s

If the bitmap size is not a multiple of BITS_PER_LONG, and no set
(cleared) bit is found, find_next_bit (find_next_zero_bit) returns a
value outside of the range [0, size]. The generic version always returns
exactly size. The generic version also uses unsigned long everywhere,
while the x86 versions use a mishmash of int, unsigned (int), long and
unsigned long.

Using the generic version does give a slightly bigger kernel, though.

defconfig:	   text    data     bss     dec     hex filename
x86-specific:	4738555  481232  626688 5846475  5935cb vmlinux (32 bit)
generic:	4738621  481232  626688 5846541  59360d vmlinux (32 bit)
x86-specific:	5392395  846568  724424 6963387  6a40bb vmlinux (64 bit)
generic:	5392458  846568  724424 6963450  6a40fa vmlinux (64 bit)

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Linus Torvalds
9e9abecfc0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86: (613 commits)
  x86: standalone trampoline code
  x86: move suspend wakeup code to C
  x86: coding style fixes to arch/x86/kernel/acpi/sleep.c
  x86: setup_trampoline() - fix section mismatch warning
  x86: section mismatch fixes, #1
  x86: fix paranoia about using BIOS quickboot mechanism.
  x86: print out buggy mptable
  x86: use cpu_online()
  x86: use cpumask_of_cpu()
  x86: remove unnecessary tmp local variable
  x86: remove unnecessary memset()
  x86: use ioapic_read_entry() and ioapic_write_entry()
  x86: avoid redundant loop in io_apic_level_ack_pending()
  x86: remove superfluous initialisation in boot code.
  x86: merge mpparse_{32,64}.c
  x86: unify mp_register_gsi
  x86: unify mp_config_acpi_legacy_irqs
  x86: unify mp_register_ioapic
  x86: unify uniq_io_apic_id
  x86: unify smp_scan_config
  ...
2008-04-18 08:25:51 -07:00
Paolo Ciarrocchi
3f50dbc1ae x86: coding style fixes to arch/x86/lib/usercopy_32.c
Before:
 total: 63 errors, 2 warnings, 878 lines checked
After:
 total: 0 errors, 2 warnings, 878 lines checked

Compile tested, no change in the binary output:

text    data     bss     dec     hex filename
3231       0       0    3231     c9f usercopy_32.o.after
3231       0       0    3231     c9f usercopy_32.o.before

md5sum:
9f9a3eb43970359ae7cecfd1c9e7cf42  usercopy_32.o.after
9f9a3eb43970359ae7cecfd1c9e7cf42  usercopy_32.o.before

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00