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Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Catalin Marinas fd522a8dec ARM: 6006/1: ARM: Use the correct NOP size in memmove for Thumb-2 kernel builds
When compiling the kernel to Thumb-2, using a 16-bit NOP in the
memmove() implementation causes the preceding ADD PC instruction to
branch incorrectly in the middle of a 32-bit LDR or STR instruction. The
memmove() code is now similar to the memcpy() template.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-03-29 17:33:33 +01:00
Russell King 40d743b8c1 Merge branch 'for-rmk' of git://linux-arm.org/linux-2.6 2009-09-19 13:47:57 +01:00
Kirill A. Shutemov dca230f00d ARM: 5701/1: ARM: copy_page.S: take into account the size of the cache line
Optimized version of copy_page() was written with assumption that cache
line size is 32 bytes. On Cortex-A8 cache line size is 64 bytes.

This patch tries to generalize copy_page() to work with any cache line
size if cache line size is multiple of 16 and page size is multiple of
two cache line size.

After this optimization we've got ~25% speedup on OMAP3(tested in
userspace).

There is test for kernelspace which trigger copy-on-write after fork():

 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>

 #define BUF_SIZE (10000*4096)
 #define NFORK 200

 int main(int argc, char **argv)
 {
         char *buf = malloc(BUF_SIZE);
         int i;

         memset(buf, 0, BUF_SIZE);

         for(i = 0; i < NFORK; i++) {
                 if (fork()) {
                         wait(NULL);
                 } else {
                         int j;

                         for(j = 0; j < BUF_SIZE; j+= 4096)
                                 buf[j] = (j & 0xFF) + 1;
                         break;
                 }
         }

         free(buf);
         return 0;
 }

Before optimization this test takes ~66 seconds, after optimization
takes ~56 seconds.

Signed-off-by: Siarhei Siamashka <siarhei.siamashka@nokia.com>
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-09-15 22:07:02 +01:00
Nicolas Pitre 2f82af08fc Nicolas Pitre has a new email address
Due to problems at cam.org, my nico@cam.org email address is no longer
valid.  FRom now on, nico@fluxnic.net should be used instead.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-15 09:37:12 -07:00
Russell King 9b2616c2e8 Merge branch 'for-rmk-2.6.32' of git://git.pengutronix.de/git/ukl/linux-2.6 into devel-stable 2009-08-15 16:51:48 +01:00
Uwe Kleine-König 0d928b0b61 Complete irq tracing support for ARM
Before this patch enabling and disabling irqs in assembler code and by
the hardware wasn't tracked completly.

I had to transpose two instructions in arch/arm/lib/bitops.h because
restore_irqs doesn't preserve the flags with CONFIG_TRACE_IRQFLAGS=y

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2009-08-13 20:34:37 +02:00
Catalin Marinas 8b592783a2 Thumb-2: Implement the unified arch/arm/lib functions
This patch adds the ARM/Thumb-2 unified support for the arch/arm/lib/*
files.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:32:57 +01:00
Catalin Marinas 88987ef91b Thumb-2: Add some .align statements to the .S files
Since the Thumb-2 instructions can be 16-bit wide, data in the .text
sections may not be aligned to a 32-bit word and this leads to unaligned
exceptions. This patch does not affect the ARM code generation.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:32:52 +01:00
Russell King 98797a241e Merge branch 'copy_user' of git://git.marvell.com/orion into devel 2009-06-14 10:59:32 +01:00
Nicolas Pitre c626e3f5ca [ARM] alternative copy_to_user: more precise fallback threshold
Previous size thresholds were guessed from various user space benchmarks
using a kernel with and without the alternative uaccess option.  This
is however not as precise as a kernel based test to measure the real
speed of each method.

This adds a simple test bench to show the time needed for each method.
With this, the optimal size treshold for the alternative implementation
can be determined with more confidence.  It appears that the optimal
threshold for both copy_to_user and clear_user is around 64 bytes. This
is not a surprise knowing that the memcpy and memset implementations
need at least 64 bytes to achieve maximum throughput.

One might suggest that such test be used to determine the optimal
threshold at run time instead, but results are near enough to 64 on
tested targets concerned by this alternative copy_to_user implementation,
so adding some overhead associated with a variable threshold is probably
not worth it for now.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-05-30 01:10:15 -04:00
Nicolas Pitre cb9dc92c0a [ARM] lower overhead with alternative copy_to_user for small copies
Because the alternate copy_to_user implementation has a higher setup cost
than the standard implementation, the size of the memory area to copy
is tested and the standard implementation invoked instead when that size
is too small.  Still, that test is made after the processor has preserved
a bunch of registers on the stack which have to be reloaded right away
needlessly in that case, causing a measurable performance regression
compared to plain usage of the standard implementation only.

To make the size test overhead negligible, let's factorize it out of
the alternate copy_to_user function where it is clear to the compiler
that no stack frame is needed.  Thanks to CONFIG_ARM_UNWIND allowing
for frame pointers to be disabled and tail call optimization to kick in,
the overhead in the small copy case becomes only 3 assembly instructions.

A similar trick is applied to clear_user as well.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-05-29 22:38:33 -04:00
Lennert Buytenhek 39ec58f3fe [ARM] alternative copy_to_user/clear_user implementation
This implements {copy_to,clear}_user() by faulting in the userland
pages and then using the regular kernel mem{cpy,set}() to copy the
data (while holding the page table lock).  This is a win if the regular
mem{cpy,set}() implementations are faster than the user copy functions,
which is the case e.g. on Feroceon, where 8-word STMs (which memcpy()
uses under the right conditions) give significantly higher memory write
throughput than a sequence of individual 32bit stores.

Here are numbers for page sized buffers on some Feroceon cores:

 - copy_to_user on Orion5x goes from 51 MB/s to 83 MB/s
 - clear_user on Orion5x goes from 89MB/s to 314MB/s
 - copy_to_user on Kirkwood goes from 240 MB/s to 356 MB/s
 - clear_user on Kirkwood goes from 367 MB/s to 1108 MB/s
 - copy_to_user on Disco-Duo goes from 248 MB/s to 398 MB/s
 - clear_user on Disco-Duo goes from 328 MB/s to 1741 MB/s

Because the setup cost is non negligible, this is worthwhile only if
the amount of data to copy is large enough.  The operation falls back
to the standard implementation when the amount of data is below a certain
threshold. This threshold was determined empirically, however some targets
could benefit from a lower runtime determined value for optimal results
eventually.

In the copy_from_user() case, this technique does not provide any
worthwhile performance gain due to the fact that any kind of read access
allocates the cache and subsequent 32bit loads are just as fast as the
equivalent 8-word LDM.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Tested-by: Martin Michlmayr <tbm@cyrius.com>
2009-05-29 22:36:45 -04:00
Nicolas Pitre a1f98849fd [ARM] allow for alternative __copy_to_user/__clear_user implementations
This allows for optional alternative implementations of __copy_to_user
and __clear_user, with a possible runtime fallback to the standard
version when the alternative provides no gain over that standard
version. This is done by making the standard __copy_to_user into a weak
alias for the symbol __copy_to_user_std.  Same thing for __clear_user.

Those two functions are particularly good candidates to have alternative
implementations for, since they rely on the STRT instruction which has
lower performances than STM instructions on some CPU cores such as
the ARM1176 and Marvell Feroceon.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-05-29 22:34:45 -04:00
Russell King bac4e960b5 [ARM] barriers: improve xchg, bitops and atomic SMP barriers
Mathieu Desnoyers pointed out that the ARM barriers were lacking:

- cmpxchg, xchg and atomic add return need memory barriers on
  architectures which can reorder the relative order in which memory
  read/writes can be seen between CPUs, which seems to include recent
  ARM architectures. Those barriers are currently missing on ARM.

- test_and_xxx_bit were missing SMP barriers.

So put these barriers in.  Provide separate atomic_add/atomic_sub
operations which do not require barriers.

Reported-Reviewed-and-Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-28 19:39:27 +01:00
Russell King 31bccbf392 Merge branch 'clps7500' into devel
Conflicts:

	arch/arm/Kconfig
2008-11-27 12:39:43 +00:00
Russell King 635f0258e5 [ARM] clps7500: remove support
The CLPS7500 platform has not built since 2.6.22-git7 and there
seems to be no interest in fixing it.  So, remove the platform
support.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-27 12:38:11 +00:00
Russell King 59f0cb0fdd [ARM] remove memzero()
As suggested by Andrew Morton, remove memzero() - it's not supported
on other architectures so use of it is a potential build breaking bug.
Since the compiler optimizes memset(x,0,n) to __memzero() perfectly
well, we don't miss out on the underlying benefits of memzero().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-27 12:37:59 +00:00
Russell King 6a4690c22f Merge branch 'ptebits' into devel
Conflicts:

	arch/arm/Kconfig
2008-10-09 21:31:56 +01:00
Catalin Marinas 22acc4e650 [ARM] 5231/1: Do not save the frame pointer in the csum_partial_copy_* functions
Since the other assembly functions do not seem to save the frame
pointer onto the stack, this patch changes the csum_partial_copy_*
functions to behave in the same way.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-01 12:06:35 +01:00
Catalin Marinas 9c23e5fefa [ARM] 5232/1: Do not post-index STRT instruction in clear_user.S
The last strnebt instruction has a post-index of 1 but the address
register is set to 0 in the next instruction, so no need for
post-indexing.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-01 12:06:34 +01:00
Catalin Marinas 93ed397011 [ARM] 5227/1: Add the ENDPROC declarations to the .S files
This declaration specifies the "function" type and size for various
assembly functions, mainly needed for generating the correct branch
instructions in Thumb-2.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-01 12:06:34 +01:00
Jean-Christophe DUBOIS 212496fd9a [ARM] 5226/1: remove unmatched comment end.
remove unmatched comment end.

Signed-off-by: Jean-Christophe DUBOIS <jcd@tribudubois.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-28 17:12:29 +01:00
Russell King a09e64fbc0 [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach
This just leaves include/asm-arm/plat-* to deal with.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07 09:55:48 +01:00
Russell King be50972935 [ARM] Remove asm/hardware.h, use asm/arch/hardware.h instead
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h.
Then, since asm/hardware.h only exists to include asm/arch/hardware.h,
update everything to directly include asm/arch/hardware.h and remove
asm/hardware.h.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07 09:40:08 +01:00
Russell King 4baa992243 [ARM] move include/asm-arm to arch/arm/include/asm
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-02 21:32:35 +01:00
Nicolas Pitre f91a8dcc25 [ARM] cache align memset and memzero
This is a natural extension following the previous patch.
Non Feroceon based targets are unchanged.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:39 +02:00
Nicolas Pitre 2239aff6ab [ARM] cache align destination pointer when copying memory for some processors
The implementation for memory copy functions on ARM had a (disabled)
provision for aligning the source pointer before loading registers with
data.  Turns out that aligning the _destination_ pointer is much more
useful, as the read side is already sufficiently helped with the use of
preload.

So this changes the definition of the CALGN() macro to target the
destination pointer instead, and turns it on for Feroceon processors
where the gain is very noticeable.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:38 +02:00
Nicolas Pitre 4c4925c1f4 [ARM] fix cache alignment code in memset.S
This code is currently disabled, which explains why no one was affected.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
2008-06-22 22:44:37 +02:00
Simon Arlott 6cbdc8c535 [ARM] spelling fixes
Spelling fixes in arch/arm/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-05-20 20:10:32 +01:00
Russell King 235b185ce4 [ARM] getuser.S and putuser.S don't need thread_info.h nor asm-offsets.h
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-21 20:35:22 +01:00
Russell King 7ab3f8d595 [ARM] Add ability to dump exception stacks to kernel backtraces
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-21 20:34:34 +01:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Russell King 583e7f5d36 [ARM] nommu: backtrace code must not reference a discarded section
The code in "1007:" is in the .fixup section, which in the mmuless
case is discarded.  Since this code is referenced from the .text
section, it causes an link error.  Move this code into the .text
section instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-28 17:59:57 +01:00
Russell King 9641c7cc5a [ARM] nommu: uaccess tweaks
MMUless systems have only one address space for all threads, so
both the usual access_ok() checks, and the exception handling do
not make much sense.

Hence, discard the fixup and exception tables at link time, use
memcpy/memset for the user copy/clearing functions, and define
the permission check macros to be constants.

Some of this patch was derived from the equivalent patch by
Hyok S. Choi.

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-28 17:59:46 +01:00
Russell King 02fcb97436 [ARM] Remove the __arch_* layer from uaccess.h
Back in the days when we had armo (26-bit) and armv (32-bit) combined,
we had an additional layer to the uaccess macros to ensure correct
typing.  Since we no longer have 26-bit in this tree, we no longer
need this layer, so eliminate it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-28 17:53:27 +01:00
Russell King 405040a78b [ARM] Remove save_lr/restore_pc macros
As for RETINSTR/LOADREGS macros, these were for compatibility
with 26-bit ARMs.  No longer required, so remove them.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-25 11:37:09 +01:00
Russell King 1b93a71755 [ARM] Remove LOADREGS macro
As for RETINSTR, LOADREGS is a left-over from the 26-bit days.
Remove it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-25 11:23:45 +01:00
Russell King 7999d8d7a6 [ARM] Remove RETINSTR macro
RETINSTR is a left-over from the days when we had 26-bit and
32-bit CPU support integrated into the same tree.  Since this
is no longer the case, we can now remove RETINSTR.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-25 11:17:23 +01:00
Nicolas Pitre 1d6760a3ac [ARM] 3524/1: ARM EABI: more 64-bit aligned stack fixes
Patch from Nicolas Pitre

Assembly code that calls C code must ensure the C code sees a 64-bit
aligned stack pointer.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-05-16 11:39:31 +01:00
Linus Torvalds ca9ba4471c Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] 3388/1: ixp23xx: add core ixp23xx support
  [ARM] 3417/1: add support for logicpd pxa270 card engine
  [ARM] 3387/1: ixp23xx: add defconfig
  [ARM] 3377/2: add support for intel xsc3 core
  [ARM] Move ice-dcc code into misc.c
  [ARM] Fix decompressor serial IO to give CRLF not LFCR
  [ARM] proc-v6: mark page table walks outer-cacheable, shared.  Enable NX.
  [ARM] nommu: trivial patch for arch/arm/lib/Makefile
  [ARM] 3416/1: Update LART site URL
  [ARM] 3415/1: Akita: Add missing EXPORT_SYMBOL
  [ARM] 3414/1: ep93xx: reset ethernet controller before uncompressing
2006-03-28 13:53:03 -08:00
Alexey Dobriyan 7f927fcc2f [PATCH] Typo fixes
Fix a lot of typos.  Eyeballed by jmc@ in OpenBSD.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:08 -08:00
Hyok S. Choi 4682adcfb0 [ARM] nommu: trivial patch for arch/arm/lib/Makefile
ifeq ($CONFIG_PREEMPT,y) -> ifeq ($(CONFIG_PREEMPT),y)

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-27 15:46:06 +01:00
Malcolm Parsons 3ee357f0f3 [ARM] 3399/1: Fix link problem when CONFIG_PRINTK is disabled
Patch from Malcolm Parsons

Printking a backtrace requires printk, so disable backtrace code
when printk is disabled.

Without this patch, a kernel with CONFIG_PRINTK disabled does not link:

arch/arm/lib/lib.a(backtrace.o): In function `c_backtrace':
arch/arm/lib/backtrace.S:(.text+0x108): undefined reference to `printk'
arch/arm/lib/backtrace.S:(.text+0x11c): undefined reference to `printk'
arch/arm/lib/lib.a(backtrace.o):(.fixup+0x8): undefined reference to `printk'

Signed-off-by: Malcolm Parsons <malcolm.parsons@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-25 21:58:03 +00:00
Peter Teichmann 6d4518d76f [ARM] 3346/1: Fix udelay() for HZ values different from 100
Patch from Peter Teichmann

Currently, if the kernels HZ value is greater than 100, delays with the udelay function are too short. This can cause trouble for instance with the zd1201 usb wlan driver.

This patch suggests a solution that keeps the overhead small and maintains (hopefully) sufficient resolution.

Signed-off-by: Peter Teichmann
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-21 22:06:07 +00:00
Russell King f78f104368 [ARM] Remove unnecessary asm/hardware.h includes
asm/hardware.h is not required for the majority of processor support
files, ioremap support, mm initialisation, acorn IO support, nor
the debug code (which picks up its machine specific includes via
debug-macros.S)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-21 22:05:50 +00:00
Russell King 3c8fdae78c [ARM] Fix muldi3.S
When shifting the low-parts of signed numbers, a logical shift
should be used to avoid sign-extending a bit which isn't a sign
bit.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-08 17:25:33 +00:00
Nicolas Pitre ba95e4e4a0 [ARM] 3104/1: ARM EABI: new helper function names
Patch from Nicolas Pitre

The ARM EABI defines new names for GCC helper functions.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-14 16:18:29 +00:00
Nicolas Pitre 499b2ea11f [ARM] 3103/1: ARM EABI: stack pointer must be 64-bit aligned (part 2)
Patch from Nicolas Pitre

We must make sure that assembly code that modifies the stack pointer
before calling a C function does it so it remains 64-bit aligned.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-14 16:18:09 +00:00
Catalin Marinas 90303b1023 [ARM] 3256/1: Make the function-returning ldm's use sp as the base register
Patch from Catalin Marinas

If the low interrupt latency mode is enabled for the CPU (from ARMv6
onwards), the ldm/stm instructions are no longer atomic. An ldm instruction
restoring the sp and pc registers can be interrupted immediately after sp
was updated but before the pc. If this happens, the CPU restores the base
register to the value before the ldm instruction but if the base register
is not sp, the interrupt routine will corrupt the stack and the restarted
ldm instruction will load garbage.

Note that future ARM cores might always run in the low interrupt latency
mode.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-12 16:53:51 +00:00
Russell King d2c5b69099 [ARM] Fix get_user when passed a const pointer
Unfortunately, later gcc versions error out when our get_user is passed
a const pointer, since we write to a temporary variable declared as
typeof(*(p)) which propagates the const-ness.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-18 14:22:03 +00:00
Nicolas Pitre 8adbb3718d [ARM] 3152/1: make various assembly local labels actually local (the rest)
Patch from Nicolas Pitre

For assembly labels to actually be local they must start with ".L" and
not only "." otherwise they still remain visible in the final link and
clutter kallsyms needlessly, and possibly make for unclear symbolic
backtrace. This patch simply inserts a"L" where appropriate. The code
itself is unchanged.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-11 21:51:49 +00:00
Nicolas Pitre a9c4814d8d [ARM] 3151/1: make various assembly local labels actually local (io-*.S)
Patch from Nicolas Pitre

For assembly labels to actually be local they must start with ".L" and
not only "." otherwise they still remain visible in the final link and
clutter kallsyms needlessly, and possibly make for unclear symbolic
backtrace. This patch simply inserts a"L" where appropriate. The code
itself is unchanged.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-11 21:51:48 +00:00
Nicolas Pitre 7ba11a9c15 [ARM] 3150/1: make various assembly local labels actually local (uaccess.S)
Patch from Nicolas Pitre

For assembly labels to actually be local they must start with ".L" and
not only "." otherwise they still remain visible in the final link and
clutter kallsyms needlessly, and possibly make for unclear symbolic
backtrace. This patch simply inserts a"L" where appropriate. The code
itself is unchanged.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-11 21:51:47 +00:00
Russell King af36bef0c5 [ARM] Fix csumpartial corner case
Ji-In Park discovered a bug in csumpartial which caused wrong
checksums with misaligned buffers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-10 11:40:53 +00:00
Russell King 59d1ff3bfb [ARM] Clean up save_and_disable_irqs macro and allow use of ARMv6 CPSID
save_and_disable_irqs does not need to use mov + msr (which was
introduced to work around a documentation bug which was propagated
into binutils.)  Use msr with an immediate constant, and if we're
building for ARMv6 or later, use the new CPSID instruction.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-09 15:04:22 +00:00
Nicolas Pitre 73f0f7c79b [ARM] 3094/1: remove PLD stuff from old uaccess code
Patch from Nicolas Pitre

ARM processors that have pld instructions are not using those copy_user
implementation anymore.  Let's remove the useless PLD lines which were
half wrong anyway.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-04 17:15:43 +00:00
Russell King 4a5f79e7e6 [ARM SMP] Add configuration option for ARMv6K processors
The 'K' extension adds several new instructions to the ARMv6 ISA
which are primerily useful for SMP.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-03 15:48:21 +00:00
Nicolas Pitre fadab0943d [ARM] 2948/1: new preemption safe copy_{to|from}_user implementation
Patch from Nicolas Pitre

This patch provides a preemption safe implementation of copy_to_user
and copy_from_user based on the copy template also used for memcpy.
It is enabled unconditionally when CONFIG_PREEMPT=y.  Otherwise if the
configured architecture is not ARMv3 then it is enabled as well as it
gives better performances at least on StrongARM and XScale cores.  If
ARMv3 is not too affected or if it doesn't matter too much then
uaccess.S could be removed altogether.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-01 19:52:24 +00:00
Nicolas Pitre 7549423000 [ARM] 2947/1: copy template with new memcpy/memmove
Patch from Nicolas Pitre

This patch provides a new implementation for optimized memory copy
functions on ARM.  It is made of two levels: a template that consists of
the core copy code and separate files that define macros to be used with
the core code depending on the type of copy needed. This allows for best
performances while sharing the same core for implementing memcpy(),
copy_from_user() and copy_to_user() for instance.

Two reasons for this work:

1) the current copy_to_user/copy_from_user implementation assumes no
   task switch will ever occur in the middle of each copied page making
   it completely unsafe with CONFIG_PREEMPT=y.

2) current copy implementations are measurably suboptimal and optimizing
   different implementations separately is a pain and more opportunities
   for bugs.

The reason for (1) is the fact that copy inside user pages are performed
with the ldm instruction which has no mean for testing user protections
and could possibly race with process preemption bypassing the COW mechanism
for example.  This is a longstanding issue that we said ought to be fixed
for about two years now.  The solution is to substitute those ldm insns
with a series of ldrt or strt insns to enforce user memory protection.
At least on StrongARM and XScale cores the ldm is not faster than the
equivalent ldr/str insns with a warm i-cache so there is no measurable
performance degradation with that change. The fact that the copy code is
a template makes it pretty easy to reuse the same core code as for memcpy
and benefit from the same performance optimizations.

Now (2) is best demonstrated with actual throughput measurements.
First, here is a summary of memcopy tests performed on a StrongARM core:

	PTR alignment	buffer size	kernel version	this version
	------------------------------------------------------------
	  aligned	     32		 59.73		107.43
	unaligned	     32		 61.31		 74.72
	  aligned	    100		132.47		136.15
	unaligned	    100	    	103.84		123.76
	  aligned	   4096		130.67		130.80
	unaligned	   4096	    	130.68		130.64
	  aligned	1048576		 68.03		68.18
	unaligned	1048576		 68.03		68.18

The buffer size is in bytes and the measured speed in MB/s.  The copy
was performed repeatedly with given buffer and throughput averaged over
3 seconds.

Here we can see that the current kernel version has a higher entry cost
that shows up with small buffers.  As buffer size grows both implementation
converge to the same throughput.

Now here's the exact same test performed on an XScale core (PXA255):

	PTR alignment	buffer size	kernel version	this version
	------------------------------------------------------------
	  aligned	     32		 46.99		 77.58
	unaligned	     32		 53.61		 59.59
	  aligned	    100		107.19		136.59
	unaligned	    100		 83.61		 97.58
	  aligned	   4096		129.13		129.98
	unaligned	   4096		128.36		128.53
	  aligned	1048576		 53.76		 59.41
	unaligned	1048576		 33.67		 56.96

Again we can see the entry setup cost being higher for the current kernel
before getting to the main copy loop.  Then throughput results converge
as long as the buffer remains in the cache. Then the 1MB case shows more
differences probably due to better pld placement and/or less instruction
interlocks in this proposed implementation.

Disclaimer: The PXA system was running with slower clocks than the
StrongARM system so trying to infer any conclusion by comparing those
separate sets of results side by side would be completely inappropriate.

So...  What this patch does is to replace both memcpy and memmove with
an implementation based on the provided copy code template.  The memmove
code is kept separate since it is used only if the memory areas involved
do overlap in which case the code is a transposition of the template but
with the copy occurring in the opposite direction (trying to fit that
mode into the template turned it into a mess not worth it for memmove
alone).  And obviously both memcpy and memmove were tested with all kinds
of pointer alignments and buffer sizes to exercise all code paths for
correctness.

The next patch will provide the now trivial replacement implementation
copy_to_user and copy_from_user.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-01 19:52:23 +00:00
Nicolas Pitre a0c6fdb987 [ARM] 2946/2: split --arch_clear_user() out of lib/uaccess.S
Patch from Nicolas Pitre

Required for future enhancement patches.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-01 19:52:22 +00:00
Nicolas Pitre f741a1aab5 [ARM] 3049/1: More optimized libgcc functions
Patch from Nicolas Pitre

This patch gets rid of the last C implementations of needed libgcc
functions for the kernel, replacing them with optimized assembly
versions.

Those functions are:

__ashldi3
__ashrdi3
__lshrdi3
__muldi3
__ucmpdi2

The first 3 were lifted from gcc, the other two were written from scratch.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-30 23:08:03 +00:00
Nicolas Pitre c09f98271f [ARM] 2930/1: optimized sha1 implementation for ARM
Patch from Nicolas Pitre

Here's an ARM assembly SHA1 implementation to replace the default C
version. It is approximately 50% faster than the generic C version. On
an XScale processor running at 400MHz:
	generic C version:	9.8 MB/s
	my version:		14.5 MB/s
This code is useful to quite a few callers in the tree:
crypto/sha1.c:		sha_transform(sctx->state, sctx->buffer, temp);
crypto/sha1.c:			sha_transform(sctx->state, &data[i], temp);
drivers/char/random.c:		sha_transform(buf, (__u8 *)r->pool+i, buf + 5);
drivers/char/random.c:	sha_transform(buf, (__u8 *)data, buf + 5);
net/ipv4/syncookies.c:	sha_transform(tmp + 16, (__u8 *)tmp, tmp + 16 + 5);

Signed-off-by: Nicolas Pitre <nico@cam.org>
Seems to work fine on big-endian as well.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-28 15:26:40 +01:00
Sam Ravnborg e6ae744dd2 kbuild: arm - use generic asm-offsets.h support
Delete obsoleted stuff from arch Makefile and rename
constants.h to asm-offsets.h

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-09 21:08:59 +02:00
Russell King 3c4ee4e252 [ARM SMP] Only enable V6K instructions on V6 MP core CPUs
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-10 14:41:45 +01:00
Russell King e7ec02938d [ARM SMP] Fix another ARMv6 bitop problem
We sometimes forgot to check whether the exclusive store succeeded.
Ensure that we always check.  Also ensure that we always use the
out of line versions, since the inline versions are not SMP safe.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-07-28 20:36:26 +01:00
Russell King 614d73edae [ARM SMP] Fix data corruption in test_* bitops
If we found that the bit was already in the desired state, we
would skip performing the operation, and write random data back.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-07-27 23:00:05 +01:00
Alexander Schulz b7523418f6 [PATCH] ARM: 2815/1: Shark: new defconfig, fixes with __io and serial ports
Patch from Alexander Schulz

This patch brings a new default config file for the shark and
fixes a compilation issue with io addressing and a runtime
problem with the serial ports, where I corrected a wrong
regshift value.
These are all shark specific files so I hope it is ok to
put them in one patch.

Signed-off-by: Alexander Schulz <alex@shark-linux.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-07-16 17:17:18 +01:00
Russell King 54ea06f6af [PATCH] ARM: Convert bitops to use ARMv6 ldrex/strex instructions
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-07-16 15:21:51 +01:00
Nicolas Pitre c7e7887666 [PATCH] ARM: 2723/2: remove __udivdi3 and __umoddi3 from the kernel
Patch from Nicolas Pitre

Those are big, slow and generally not recommended for kernel code.
They are even not present on i386.  So it should be concluded that
one could as well get away with do_div() alone.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-29 18:10:54 +01:00
Russell King 3ade2fe0fd [PATCH] ARM: Lindent GCC helper functions
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-20 16:45:32 +01:00
Russell King f29481c0e7 [PATCH] ARM: Remove gcc type-isms from GCC helper functions
Convert ugly GCC types to Linux types:

	UQImode -> u8
	SImode -> s32
	USImode -> u32
	DImode -> s64
	UDImode -> u64
	word_type -> int

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-20 15:49:59 +01:00
Nicolas Pitre aeabbbbe12 [PATCH] ARM: 2705/1: fix writesw for misaligned source pointer
Patch from Nicolas Pitre

Signed-off-by: Nicolas Pitre
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-08 19:00:16 +01:00
Russell King 7a55fd0bb3 [PATCH] ARM: Add missing new file for bitops patch
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-18 22:50:01 +01:00
Russell King 684f970e2f [PATCH] ARM: bitops
Convert ARM bitop assembly to a macro.  All bitops follow the same
format, so it's silly duplicating the code when only one or two
instructions are different.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
2005-04-17 15:51:02 +01:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00