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  1. 27 4月, 2008 3 次提交
    • A
      x86: generic versions of find_first_(zero_)bit, convert i386 · 77b9bd9c
      由 Alexander van Heukelum 提交于 
      Generic versions of __find_first_bit and __find_first_zero_bit
are introduced as simplified versions of __find_next_bit and
__find_next_zero_bit. Their compilation and use are guarded by
a new config variable GENERIC_FIND_FIRST_BIT.

The generic versions of find_first_bit and find_first_zero_bit
are implemented in terms of the newly introduced __find_first_bit
and __find_first_zero_bit.

This patch does not remove the i386-specific implementation,
but it does switch i386 to use the generic functions by setting
GENERIC_FIND_FIRST_BIT=y for X86_32.
Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      77b9bd9c
    • A
      x86: change x86 to use generic find_next_bit · 6fd92b63
      由 Alexander van Heukelum 提交于 
      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: NAlexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      6fd92b63
    • I
      x86 PAT: decouple from nonpromisc devmem · 2a8a2719
      由 Ingo Molnar 提交于 
      Linus pointed it out that PAT should not depend on NONPROMISC_DEVMEM.

Also make PAT non-default.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2a8a2719
  3. 26 4月, 2008 2 次提交
  5. 25 4月, 2008 1 次提交
  7. 20 4月, 2008 2 次提交
  9. 18 4月, 2008 1 次提交
  11. 17 4月, 2008 11 次提交
  13. 13 3月, 2008 1 次提交
  15. 12 3月, 2008 1 次提交
    • T
      x86: remove quicklists · 985a34bd
      由 Thomas Gleixner 提交于 
      quicklists cause a serious memory leak on 32-bit x86,
as documented at:

  http://bugzilla.kernel.org/show_bug.cgi?id=9991

the reason is that the quicklist pool is a special-purpose
cache that grows out of proportion. It is not accounted for
anywhere and users have no way to even realize that it's
the quicklists that are causing RAM usage spikes. It was
supposed to be a relatively small pool, but as demonstrated
by KOSAKI Motohiro, they can grow as large as:

  Quicklists:    1194304 kB

given how much trouble this code has caused historically,
and given that Andrew objected to its introduction on x86
(years ago), the best option at this point is to remove them.

[ any performance benefits of caching constructed pgds should
  be implemented in a more generic way (possibly within the page
  allocator), while still allowing constructed pages to be
  allocated by other workloads. ]
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      985a34bd
  17. 05 3月, 2008 1 次提交
  19. 04 3月, 2008 1 次提交
  21. 23 2月, 2008 1 次提交
  23. 15 2月, 2008 1 次提交
  25. 09 2月, 2008 3 次提交
  27. 08 2月, 2008 2 次提交
    • C
      SLUB: Alternate fast paths using cmpxchg_local · 1f84260c
      由 Christoph Lameter 提交于 
      Provide an alternate implementation of the SLUB fast paths for alloc
and free using cmpxchg_local. The cmpxchg_local fast path is selected
for arches that have CONFIG_FAST_CMPXCHG_LOCAL set. An arch should only
set CONFIG_FAST_CMPXCHG_LOCAL if the cmpxchg_local is faster than an
interrupt enable/disable sequence. This is known to be true for both
x86 platforms so set FAST_CMPXCHG_LOCAL for both arches.

Currently another requirement for the fastpath is that the kernel is
compiled without preemption. The restriction will go away with the
introduction of a new per cpu allocator and new per cpu operations.

The advantages of a cmpxchg_local based fast path are:

1. Potentially lower cycle count (30%-60% faster)

2. There is no need to disable and enable interrupts on the fast path.
   Currently interrupts have to be disabled and enabled on every
   slab operation. This is likely avoiding a significant percentage
   of interrupt off / on sequences in the kernel.

3. The disposal of freed slabs can occur with interrupts enabled.

The alternate path is realized using #ifdef's. Several attempts to do the
same with macros and inline functions resulted in a mess (in particular due
to the strange way that local_interrupt_save() handles its argument and due
to the need to define macros/functions that sometimes disable interrupts
and sometimes do something else).

[clameter: Stripped preempt bits and disabled fastpath if preempt is enabled]
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Reviewed-by: NPekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      1f84260c
    • B
      I8K: add i8k driver to the x86_64 Kconfig · 300ec130
      由 Bradley Smith 提交于 
      Adds i8k driver to the x86_64 Kconfig.
Signed-off-by: NBradley Smith <bradjsmith@btinternet.com>
Cc: Frank Sorenson <frank@tuxrocks.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      300ec130
  29. 07 2月, 2008 3 次提交
  31. 06 2月, 2008 2 次提交
  33. 04 2月, 2008 1 次提交
  35. 03 2月, 2008 3 次提交
    • A
      remove Documentation/smp.txt · 03502faa
      由 Adrian Bunk 提交于 
      After seeing the filename I'd have expected something about the
implementation of SMP in the Linux kernel - not some notes on kernel
configuration and building trivialities noone would search at this
place.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Acked-by: NAlan Cox <alan@redhat.com>
      03502faa
    • M
      Move Kconfig.instrumentation to arch/Kconfig and init/Kconfig · 125e5645
      由 Mathieu Desnoyers 提交于 
      Move the instrumentation Kconfig to

arch/Kconfig for architecture dependent options
  - oprofile
  - kprobes

and

init/Kconfig for architecture independent options
  - profiling
  - markers

Remove the "Instrumentation Support" menu. Everything moves to "General setup".
Delete the kernel/Kconfig.instrumentation file.
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
      125e5645
    • M
      Add HAVE_KPROBES · 3f550096
      由 Mathieu Desnoyers 提交于 
      Linus:

On the per-architecture side, I do think it would be better to *not* have
internal architecture knowledge in a generic file, and as such a line like

        depends on X86_32 || IA64 || PPC || S390 || SPARC64 || X86_64 || AVR32

really shouldn't exist in a file like kernel/Kconfig.instrumentation.

It would be much better to do

        depends on ARCH_SUPPORTS_KPROBES

in that generic file, and then architectures that do support it would just
have a

        bool ARCH_SUPPORTS_KPROBES
                default y

in *their* architecture files. That would seem to be much more logical,
and is readable both for arch maintainers *and* for people who have no
clue - and don't care - about which architecture is supposed to support
which interface...

Changelog:

Actually, I know I gave this as the magic incantation, but now that I see
it, I realize that I should have told you to just use

        config KPROBES_SUPPORT
                def_bool y

instead, which is a bit denser.

We seem to use both kinds of syntax for these things, but this is really
what "def_bool" is there for...

- Use HAVE_KPROBES
- Use a select

- Yet another update :
Moving to HAVE_* now.

- Update ARM for kprobes support.
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
      3f550096