per cpu data section contains two types of data. One set which is
exclusively accessed by the local cpu and the other set which is per cpu,
but also shared by remote cpus. In the current kernel, these two sets are
not clearely separated out. This can potentially cause the same data
cacheline shared between the two sets of data, which will result in
unnecessary bouncing of the cacheline between cpus.
One way to fix the problem is to cacheline align the remotely accessed per
cpu data, both at the beginning and at the end. Because of the padding at
both ends, this will likely cause some memory wastage and also the
interface to achieve this is not clean.
This patch:
Moves the remotely accessed per cpu data (which is currently marked
as ____cacheline_aligned_in_smp) into a different section, where all the data
elements are cacheline aligned. And as such, this differentiates the local
only data and remotely accessed data cleanly.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Identical implementations of PTRACE_POKEDATA go into generic_ptrace_pokedata()
function.
AFAICS, fix bug on xtensa where successful PTRACE_POKEDATA will nevertheless
return EPERM.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the kernel OOPSed or BUGed then it probably should be considered as
tainted. Thus, all subsequent OOPSes and SysRq dumps will report the
tainted kernel. This saves a lot of time explaining oddities in the
calltraces.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Added parisc patch from Matthew Wilson -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ARM show_regs() tombstone only partially decodes which ARM ISA was
executing at the time a fault occurred displaying either "(T)" for the
Thumb case or nothing at all for other cases. This patch therefore
explicitly identifies which state the processor is in at the time of
a fault: ARM, Thumb, Jazelle or JazelleEE.
Signed-off-by: George G. Davis <gdavis@mvista.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Examines the ATAGS pointer (r2) at boot, and interprets
a nonzero value as a reference to an ATAGS structure. A
suitable ATAGS structure replaces the kernel's command line.
Signed-off-by: Bill Gatliff <bgat@billgatliff.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Don't make this dependent on CONFIG_DEBUG_KERNEL - if we hit a WARN_ON
we need the stack trace to work out how we got to that point.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Not all the world is an i386. Many architectures need 64-bit arguments to be
aligned in suitable pairs of registers, and the original
sys_sync_file_range(int, loff_t, loff_t, int) was therefore wasting an
argument register for padding after the first integer. Since we don't
normally have more than 6 arguments for system calls, that left no room for
the final argument on some architectures.
Fix this by introducing sys_sync_file_range2(int, int, loff_t, loff_t) which
all fits nicely. In fact, ARM already had that, but called it
sys_arm_sync_file_range. Move it to fs/sync.c and rename it, then implement
the needed compatibility routine. And stop the missing syscall check from
bitching about the absence of sys_sync_file_range() if we've implemented
sys_sync_file_range2() instead.
Tested on PPC32 and with 32-bit and 64-bit userspace on PPC64.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the kernel release and version information to the output of
show_regs/oops. Add the CPU PSR register. Avoid using printk
to output partial lines; always output a complete line.
Re-combine the "Control" and "Table + DAC" lines after nommu
separated them; we don't want to waste vertical screen space
needlessly.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add calls to oops_enter() and oops_exit() to __die(), so that
things like lockdep know when an oops occurs.
Add suffixes to the oops report to indicate whether the running
kernel has been built with preempt or smp support.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix an oops in the stacktrace code, caused by improper range checking.
We subtract 12 off 'fp' before testing to see if it's below the low
bound. However, if 'fp' were zero before, it becomes a very large
positive number, causing this test to succeed where it should fail.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use the newly introduced __used attribute in place of the deprecated
__attribute_used__. Functionally the same.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fix:
mm/slab: fix section mismatch warning
mm: fix section mismatch warnings
init/main: use __init_refok to fix section mismatch
kbuild: introduce __init_refok/__initdata_refok to supress section mismatch warnings
all-archs: consolidate .data section definition in asm-generic
all-archs: consolidate .text section definition in asm-generic
kbuild: add "Section mismatch" warning whitelist for powerpc
kbuild: make better section mismatch reports on i386, arm and mips
kbuild: make modpost section warnings clearer
kconfig: search harder for curses library in check-lxdialog.sh
kbuild: include limits.h in sumversion.c for PATH_MAX
powerpc: Fix the MODALIAS generation in modpost for of devices
Fix the formating of the "CPU part" field to be consistent with
the other fields for pre-ARM7 parts. One tab to many for them to
all line up.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Presently, we check for the minimum ARM architecture that we're
building for to determine whether we need ASID support. This is
wrong - if we're going to support a range of CPUs which include
ARMv6 or higher, we need the ASID.
Convert the checks to use a new configuration symbol, and arrange
for ARMv6 and higher CPU entries to select it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add utimensat, signalfd, timerfd, eventfd syscalls. Add ignore
defines for sync_file_range and fadvise64_64 which we implement
differently.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
I've got the following linking error when building 2.6.21-mm2 on ARM:
ERROR: "csum_partial_copy_from_user" [net/rxrpc/af-rxrpc.ko] undefined!
Linking fails because "csum_partial_copy_from_user" is not exported to
modules. This patch adds it to the list of exported symbols.
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ab1b6f03a1 said
- remove the unused task argument to save_stack_trace, it's always current
then broke arm:
arch/arm/kernel/stacktrace.c:56: error: conflicting types for 'save_stack_trace'
include/linux/stacktrace.h:11: error: previous declaration of 'save_stack_trace' was here
arch/arm/kernel/stacktrace.c:56: error: conflicting types for 'save_stack_trace'
include/linux/stacktrace.h:11: error: previous declaration of 'save_stack_trace' was here
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add devres ecardm_iomap() and ecardm_iounmap() for Acorn expansion
cards. Convert all expansion card drivers to use them.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than having every driver fiddle about setting its private
IRQ operations and data, provide a helper function to contain
this functionality in one place.
Arrange to remove the driver-private IRQ operations and data when
the device is removed from the driver, and remove the driver
private code to do this.
This fixes potential problems caused by drivers forgetting to
remove these hooks.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Branches in the ARM architecture are restricted to a range of +/- 32MB.
However, the code in .../arch/arm/kernel/module.c::apply_relocate() was
checking offset against a range of +/- 64MB.
Signed-off-by: Kevin Welton <Kevin.Welton@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch moves the die notifier handling to common code. Previous
various architectures had exactly the same code for it. Note that the new
code is compiled unconditionally, this should be understood as an appel to
the other architecture maintainer to implement support for it aswell (aka
sprinkling a notify_die or two in the proper place)
arm had a notifiy_die that did something totally different, I renamed it to
arm_notify_die as part of the patch and made it static to the file it's
declared and used at. avr32 used to pass slightly less information through
this interface and I brought it into line with the other architectures.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix vmalloc_sync_all bustage]
[bryan.wu@analog.com: fix vmalloc_sync_all in nommu]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 86c0baf123 highlighted that we
may end up with the head text placed elsewhere in the kernel image.
Introduce a new .text.head section to contain the initial kernel
startup code, and always place this section at the beginning of the
kernel image.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix false warning:
WARNING: arch/arm/kernel/init_task.o - Section mismatch:
reference to .init.task:init_thread_union from .data between
'init_task' (at offset 0x4) and 'init_sighand'
caused by the section name starting with ".init".
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
utrace removes the ptrace_message field in task_struct. Move our use
of this field into a new member in thread_info called "syscall"
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Let's surround constructs like:
orr r3, r3, #(KERNEL_RAM_PADDR & 0x00f00000)
between .if .endif since (KERNEL_RAM_PADDR & 0x00f00000) is 0 in 99% of
all cases.
Also let's mask PHYS_OFFSET with 0x00f00000 instead of 0x00e00000.
Section mappings are really 1MB not 2MB and the 2MB groupping is
a higher level issue already much better enforced with
#if (PHYS_OFFSET & 0x001fffff)
#error "PHYS_OFFSET must be at an even 2MiB boundary!"
#endif
at the top of the file.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
'type' in the struct expansion_card is only used to indicate
whether this card is an EASI card or not. Therefore, having
it as an enum is wasteful (and introduces additional noise
when we come to remove the enum.) Convert it to a mere flag
instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch modifies the startup of kecardd to use kthread_run not a
kernel_thread combination of kernel_thread and daemonize. Making the code
slightly simpler and more maintainable.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Although expansion cards can't do bus-master DMA, subsystems
want to be able to use coherent memory for DMA purposes to
these cards. Therefore, set the coherent DMA mask to allow
such memory to be allocated.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Now that do_undefinstr handles kernel and user mode undefined
instruction exceptions it must not assume that interrupts are enabled at
entry.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Let's allow page-alignment in general for per-cpu data (wanted by Xen, and
Ingo suggested KVM as well).
Because larger alignments can use more room, we increase the max per-cpu
memory to 64k rather than 32k: it's getting a little tight.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add support for stacktrace. Use the new stacktrace code with
oprofile instead of it's version; there's no point having
multiple versions of stacktracing in the kernel.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
And, wrap timer_tick() and sysdev suspend/resume in
!GENERIC_CLOCKEVENTS since clockevent layer takes care
of these.
Signed-off-by: Kevin Hilman <khilman@mvista.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Lots of places in arch/arm were needlessly including linux/ptrace.h,
resumably because we used to pass a struct pt_regs to interrupt
handlers. Now that we don't, all these ptrace.h includes are
redundant.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
