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Change cris to use the new bcd2bin/bin2bcd functions instead of the
obsolete BCD_TO_BIN/BIN_TO_BCD macros.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Chris Zankel <zankel@tensilica.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch implements a new freezer subsystem in the control groups
framework. It provides a way to stop and resume execution of all tasks in
a cgroup by writing in the cgroup filesystem.
The freezer subsystem in the container filesystem defines a file named
freezer.state. Writing "FROZEN" to the state file will freeze all tasks
in the cgroup. Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup. Reading will return the current state.
* Examples of usage :
# mkdir /containers/freezer
# mount -t cgroup -ofreezer freezer /containers
# mkdir /containers/0
# echo $some_pid > /containers/0/tasks
to get status of the freezer subsystem :
# cat /containers/0/freezer.state
RUNNING
to freeze all tasks in the container :
# echo FROZEN > /containers/0/freezer.state
# cat /containers/0/freezer.state
FREEZING
# cat /containers/0/freezer.state
FROZEN
to unfreeze all tasks in the container :
# echo RUNNING > /containers/0/freezer.state
# cat /containers/0/freezer.state
RUNNING
This is the basic mechanism which should do the right thing for user space
task in a simple scenario.
It's important to note that freezing can be incomplete. In that case we
return EBUSY. This means that some tasks in the cgroup are busy doing
something that prevents us from completely freezing the cgroup at this
time. After EBUSY, the cgroup will remain partially frozen -- reflected
by freezer.state reporting "FREEZING" when read. The state will remain
"FREEZING" until one of these things happens:
1) Userspace cancels the freezing operation by writing "RUNNING" to
the freezer.state file
2) Userspace retries the freezing operation by writing "FROZEN" to
the freezer.state file (writing "FREEZING" is not legal
and returns EIO)
3) The tasks that blocked the cgroup from entering the "FROZEN"
state disappear from the cgroup's set of tasks.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: export thaw_process]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Tested-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Conflicts:
Documentation/ABI/testing/sysfs-bus-usb
drivers/Makefile
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* 'for-linus' of git://www.jni.nu/cris:
CRIS: proper defconfig setup
[CRIS] Rename boot-linkscripts and fix the path to them.
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As policy->governor is already set to CPUFREQ_DEFAULT_GOVERNOR in the
(always built-in) cpufreq core, we do not need to set it in the drivers.
This fixes the sparc64 allmodconfig build failure.
Also, remove a totally useles setting of ->policy in cpufreq-pxa3xx.c.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch moves the cris defconfigs to arch/cris/configs/ where they
belong.
As a side effect they can now be used directly through e.g.
make ARCH=cris artpec_3_defconfig
The default defconfig is set through KBUILD_DEFCONFIG.
Signed-off-by: Adrian Bunk <adrian.bunk@movial.fi>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
include/asm-x86/statfs.h
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The Kbuild and Kconfig files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David Vrabel <david.vrabel@csr.com>
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Right now, there is no notifier that is called on a new cpu, before the new
cpu begins processing interrupts/softirqs.
Various kernel function would need that notification, e.g. kvm works around
by calling smp_call_function_single(), rcu polls cpu_online_map.
The patch adds a CPU_STARTING notification. It also adds a helper function
that sends the message to all cpu_chain handlers.
Tested on x86-64.
All other archs are untested. Especially on sparc, I'm not sure if I got
it right.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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This patch also includes the required removal of (unused) inclusion of
<asm/a.out.h> <linux/a.out.h>'s in the arch/ code for these
architectures.
[dwmw2: updated for 2.6.27-rc]
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
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This patch lets the files using linux/version.h match the files that
#include it.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Conflicts:
arch/x86/Kconfig
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Remove arch-specific show_mem() in favor of the generic version.
This also removes the following redundant information display:
- free pages, printed by show_free_areas()
- pages in swapcache, printed by show_swap_cache_info()
where show_mem() calls show_free_areas(), which calls
show_swap_cache_info().
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Acked-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Inflate requires some dynamic memory allocation very early in the boot
process and this is provided with a set of four functions:
malloc/free/gzip_mark/gzip_release.
The old inflate code used a mark/release strategy rather than implement
free. This new version instead keeps a count on the number of outstanding
allocations and when it hits zero, it resets the malloc arena.
This allows removing all the mark and release implementations and unifying
all the malloc/free implementations.
The architecture-dependent code must define two addresses:
- free_mem_ptr, the address of the beginning of the area in which
allocations should be made
- free_mem_end_ptr, the address of the end of the area in which
allocations should be made. If set to 0, then no check is made on
the number of allocations, it just grows as much as needed
The architecture-dependent code can also provide an arch_decomp_wdog()
function call. This function will be called several times during the
decompression process, and allow to notify the watchdog that the system is
still running. If an architecture provides such a call, then it must
define ARCH_HAS_DECOMP_WDOG so that the generic inflate code calls
arch_decomp_wdog().
Work initially done by Matt Mackall, updated to a recent version of the
kernel and improved by me.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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free_area_init_node() gets passed in the node id as well as the node
descriptor. This is redundant as the function can trivially get the node
descriptor itself by means of NODE_DATA() and the node's id.
I checked all the users and NODE_DATA() seems to be usable everywhere
from where this function is called.
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* 'for-linus' of git://www.jni.nu/cris:
[CRISv10] Clean up compressed/misc.c
[CRISv10] Correct whitespace damage.
[CRIS] Correct definition of subdirs for install_headers.
[CRIS] Correct image makefiles to allow using a separate OBJ-directory.
[CRIS] Build fixes for compressed and rescue images for v10 and v32:
It looks at least odd to apply spin_unlock to a mutex.
cris: compile fixes for 2.6.26-rc5
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Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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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>
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This makes the CRIS-port directories follow the same naming
convention as the rest of the kernel.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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Many minor fixes in whitespace and formatting.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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The previous patch was whitespace damaged, correct to indent
using tabs.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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Make compile succeed when building with O= (srctree != objtree).
Signed-off-by: Hinko Kocevar <hinko.kocevar@cetrtapot.si>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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- Use the normal cross gcc instead of using an elf specific cris toolchain.
This removes the dependency of this second toolchain.
- Use the normal cross objcopy instead of overriding it to use elf-toolchain.
This allows compiling using "CROSS_COMPILE=$CRIS_GCC/cris-axis-linux-gnu-"
instead of just "CROSS_COMPILE=$CRIS_GCC/cris-axis-linux-gnu/bin/"
- Remove redundant rules for compiling, the implicit rules are sufficient.
- Convert the arch/cris/arch-v10/boot/compressed/head.S to format
accepted by the cris-axis-linux-gnu-gcc (registers must be prefixed
with '$', remove explicit underscore on exported symbols)
- Remove a number of unused (and duplicated) prototypes from
arch/cris/arch-v10/boot/compressed/misc.c.
- Correct memcpy and memset return values (actually return them!)
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@def@
declarer DEFINE_MUTEX;
identifier m;
@@
DEFINE_MUTEX(m);
@@
identifier def.m;
@@
(
- spin_lock(&m)
+ mutex_lock(&m)
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- spin_unlock(&m)
+ mutex_unlock(&m)
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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Add dummy ops for serial debug port.
Add setting of c_ispeed/c_ospeed as suggested by Alan Cox.
Signed-off-by: Hinko Kocevar <hinko.kocevar@cetrtapot.si>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
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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>
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All of the open() functions which don't need the BKL on their face may
still depend on its acquisition to serialize opens against driver
initialization. So make those functions acquire then release the BKL to be
on the safe side.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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This documents the fact that somebody looked at the relevant open()
functions and concluded that, due to their trivial nature, no locking was
needed.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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Push the cdev lock_kernel() call into cris drivers.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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The cris implementation of sys_pipe only differs from the generic one
by taking the BKL before calling do_pipe which isn't not nessecary.
Just kill the cris implementation and use the generic one.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Remember to close the files if copy_to_user() failed.
Spotted by dm.n9107@gmail.com.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Cc: DM <dm.n9107@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Use proc_create() to make sure that ->proc_fops be setup before gluing PDE to
main tree.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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show_mem() has no need to print the amount of free swap space manually because
show_free_areas() does this already and is called by the former.
The two outputs only differ in text formatting:
printk("Free swap = %lukB\n", ...);
printk("Free swap: %6ldkB\n", ...);
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility. Thanks to Peter Zijlstra for fixing the lockdep
warning. Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
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lib/usercopy and uaccess.h
Function __copy_user_zeroing in arch/lib/usercopy.c had the wrong parameter
set as __user, and in include/asm-cris/uaccess.h, it was not set at all for
some of the calling functions.
This will cut the number of warnings quite dramatically when using sparse.
While we're here, remove useless CVS log and correct confusing typo.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Adrian Bunk reported another compile error with a SVN head GCC:
...
CC arch/cris/arch-v10/lib/string.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/string.c:138:
error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/string.c:138:
error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/string.c:139:
error: lvalue required as increment operand
...
This is due to the use of the construct:
*((long*)dst)++ = lc;
Which isn't legal since casts don't return an lvalue.
The solution is to import the implementation from newlib,
which is continually autotested together with GCC mainline,
and uses the construct:
*(long *) dst = lc; dst += 4;
Since this is an import of a file from newlib, I'm not touching
the formatting or correcting any checkpatch errors.
As for the earlier fix for memset.c, even if the two files for
CRIS v10 and CRIS v32 are identical at the moment, it might
be possible to tweak the CRIS v32 version.
Thus, I'm not yet folding them into the same file, at least not
until we've done some research on it.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit 2f569afd9ced9ebec9a6eb3dbf6f83429be0a7b4
(CONFIG_HIGHPTE vs. sub-page page tables) introduced use of
inc_zone_page_state and dec_zone_page_state in include/linux/mm.h.
Those are defined in include/linux/vmstat.h, but after it includes
mm.h, making it impossible to include vmstat.h since inc_zone_page_state
and dec_zone_page_state then would be undefined.
arch/cris/arch-v10/kernel/time.c does just this, which makes the
CRIS v10 build break with the following error:
...
CC arch/cris/arch-v10/kernel/time.o
In file included from include/linux/vmstat.h:7,
from arch/cris/arch-v10/kernel/time.c:17:
include/linux/mm.h: In function 'pgtable_page_ctor':
include/linux/mm.h:902: error: implicit declaration of function 'inc_zone_page_state'
include/linux/mm.h: In function 'pgtable_page_dtor':
include/linux/mm.h:908: error: implicit declaration of function 'dec_zone_page_state'
make[2]: *** [arch/cris/arch-v10/kernel/time.o] Error 1
make[1]: *** [arch/cris/arch-v10/kernel] Error 2
make: *** [sub-make] Error 2
...
By changing kernel/time.c to include linux/mm.h, the build succeeds.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Adrian Bunk reported the following compile error with a SVN head GCC:
...
CC arch/cris/arch-v10/lib/memset.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c: In function 'memset':
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:164: error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:165: error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:166: error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:167: error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:185: error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:189: error: lvalue required as increment operand
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/cris/arch-v10/lib/memset.c:192: error: lvalue required as increment operand
... etc ...
This is due to the use of the construct:
*((long*)dst)++ = lc;
Which is no longer legal since casts don't return an lvalue.
The solution is to import the implementation from newlib,
which is continually autotested together with GCC mainline,
and uses the construct:
*(long *) dst = lc; dst += 4;
With this change, the generated code actually shrinks 76 bytes
since gcc notices that it can use autoincrement for the move
instruction in CRIS.
text data bss dec hex filename
304 0 0 304 130 memset.old.o
text data bss dec hex filename
228 0 0 228 e4 memset.o
Since this is an import of a file from newlib, I'm not touching
the formatting or correcting any checkpatch errors.
Note also that even if the two files for the CRIS v10 and CRIS v32
are identical at the moment, it might be possible to tweak the
CRIS v32 version. Thus, I'm not yet folding them into the same file,
at least not until we've done some research on it.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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To allow flexible configuration of IDE introduce HAVE_IDE.
All archs except arm, um and s390 unconditionally select it.
For arm the actual configuration determine if IDE is supported.
This is a step towards introducing drivers/Kconfig for arm.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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* 'cris' of git://www.jni.nu/cris: (158 commits)
CRIS v32: Remove hwregs/timer_defs.h, it is now architecture specific.
CRIS v32: Change drivers/i2c.c locking.
CRIS v32: Rewrite ARTPEC-3 gpio driver to avoid volatiles and general cleanup.
CRIS: Add new timerfd syscall entries.
MAINTAINERS: Add my information for the CRIS port.
CRIS v32: Correct spelling of bandwidth in function name.
CRIS v32: Clean up nandflash.c for ARTPEC-3 and ETRAX FS.
CRIS v10: Cleanup of drivers/gpio.c
CRIS v10: drivers/net/cris/eth_v10.c rename LED defines to CRIS_LED to avoid name clash.
CRIS: Make io_pwm_set_period members unsigned in etraxgpio.h
CRIS: Move ETRAX_AXISFLASHMAP to common Kconfig file.
CRIS: Drop regs parameter from call to profile_tick in kernel/time.c
CRIS v32: Fix minor formatting issue in mach-a3/io.c
CRIS v32: Initialize GIO even if we're rambooting in kernel/head.S
CRIS v32: Remove kernel/arbiter.c, it now exists in machine dependent directory.
CRIS v32: Minor changes to avoid errors in asm-cris/arch-v32/hwregs/reg_rdwr.h
CRIS v32: arch-v32/hwregs/intr_vect_defs.h moved to machine dependent directory.
CRIS v32: Correct offset for TASK_pid in asm-cris/arch-v32/offset.h
CRIS v32: Move register map header to machine dependent directory.
CRIS v32: Let compiler know that memory is clobbered after a break op.
...
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When the conversion factor between jiffies and milli- or microseconds is
not a single multiply or divide, as for the case of HZ == 300, we currently
do a multiply followed by a divide. The intervening result, however, is
subject to overflows, especially since the fraction is not simplified (for
HZ == 300, we multiply by 300 and divide by 1000).
This is exposed to the user when passing a large timeout to poll(), for
example.
This patch replaces the multiply-divide with a reciprocal multiplication on
32-bit platforms. When the input is an unsigned long, there is no portable
way to do this on 64-bit platforms there is no portable way to do this
since it requires a 128-bit intermediate result (which gcc does support on
64-bit platforms but may generate libgcc calls, e.g. on 64-bit s390), but
since the output is a 32-bit integer in the cases affected, just simplify
the multiply-divide (*3/10 instead of *300/1000).
The reciprocal multiply used can have off-by-one errors in the upper half
of the valid output range. This could be avoided at the expense of having
to deal with a potential 65-bit intermediate result. Since the intent is
to avoid overflow problems and most of the other time conversions are only
semiexact, the off-by-one errors were considered an acceptable tradeoff.
At Ralf Baechle's suggestion, this version uses a Perl script to compute
the necessary constants. We already have dependencies on Perl for kernel
compiles. This does, however, require the Perl module Math::BigInt, which
is included in the standard Perl distribution starting with version 5.8.0.
In order to support older versions of Perl, include a table of canned
constants in the script itself, and structure the script so that
Math::BigInt isn't required if pulling values from said table.
Running the script requires that the HZ value is available from the
Makefile. Thus, this patch also adds the Kconfig variable CONFIG_HZ to the
architectures which didn't already have it (alpha, cris, frv, h8300, m32r,
m68k, m68knommu, sparc, v850, and xtensa.) It does *not* touch the sh or
sh64 architectures, since Paul Mundt has dealt with those separately in the
sh tree.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Ralf Baechle <ralf@linux-mips.org>,
Cc: Sam Ravnborg <sam@ravnborg.org>,
Cc: Paul Mundt <lethal@linux-sh.org>,
Cc: Richard Henderson <rth@twiddle.net>,
Cc: Michael Starvik <starvik@axis.com>,
Cc: David Howells <dhowells@redhat.com>,
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>,
Cc: Hirokazu Takata <takata@linux-m32r.org>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>,
Cc: Roman Zippel <zippel@linux-m68k.org>,
Cc: William L. Irwin <sparclinux@vger.kernel.org>,
Cc: Chris Zankel <chris@zankel.net>,
Cc: H. Peter Anvin <hpa@zytor.com>,
Cc: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
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Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-By: David Howells <dhowells@redhat.com>
Acked-by: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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