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>
Building UP kernel with KGDB enabled produces the following errors and warning
(fatal due to -Werror in arch/mips/kernel/Makefile):
In file included from arch/mips/kernel/gdb-stub.c:142:
include/asm/smp.h:25:1: "raw_smp_processor_id" redefined
In file included from include/linux/sched.h:69,
from arch/mips/kernel/gdb-stub.c:126:
include/linux/smp.h:88:1: this is the location of the previous definition
In file included from arch/mips/kernel/gdb-stub.c:142:
include/asm/smp.h:62: error: redefinition of 'smp_send_reschedule'
include/linux/smp.h:102: error: previous definition of 'smp_send_reschedule' was here
include/asm/smp.h: In function `smp_send_reschedule':
include/asm/smp.h:65: error: dereferencing pointer to incomplete type
arch/mips/kernel/gdb-stub.c: At top level:
arch/mips/kernel/gdb-stub.c:660: warning: 'kgdb_wait' defined but not used
Fix the errors by not directly including <asm/smp.h> (which is already included
by <linux/smp.h>) and the warning by enclosing kgdb_wait() in #ifdef CONFIG_SMP.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
And while at it, make it a little cleaner. Issue originally reported by
Tiejun Chen (tiejun.chen@windriver.com).
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some of these are architecturally required for R2 processors so lets try
to be bit closer to the real thing. This also provides access to the
CPU cycle timer, even on multiprocessors. In that aspect its currently
bug compatible to what would happen on a R2-based SMP.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch enables the system calls timerfd_create(), timerfd_settime()
and timerfd_gettime() for MIPS architecture.
Please see the following Bugzilla entry for more details:
http://bugzilla.kernel.org/show_bug.cgi?id=10038
This was tested using a Malta 4Kc board in both little-endian and
big-endian modes. The unit test program is available from the URL
above.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
[Ralf: Added N64, N32 and O32 bits on 64-bit kernels.]
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Properly acknowledge RM7K and RM9K interrupts. Before this, interrupts were
permanently masked after their first occurrence, making them non-functional.
Signed-off-by: Thomas Koeller <thomas.koeller@baslerweb.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
There are some places left in mips, that lookup task in initial namespace,
while the code doing so gets the pid from the user space and thus must
treat it as virtual.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Add path_put() functions for releasing a reference to the dentry and
vfsmount of a struct path in the right order
* Switch from path_release(nd) to path_put(&nd->path)
* Rename dput_path() to path_put_conditional()
[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use set_irq_noprobe() to mark all MIPS interrupts as non-probe. Override that
default for i8259 interrupts.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-and-tested-by: Rob Landley <rob@landley.net>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.
This patch:
Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past. This is to avoid conflicts.
Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
calibrate_delay() must be __cpuinit, not __{dev,}init.
I've verified that this is correct for all users.
While doing the latter, I also did the following cleanups:
- remove pointless additional prototypes in C files
- ensure all users #include <linux/delay.h>
This fixes the following section mismatches with CONFIG_HOTPLUG=n,
CONFIG_HOTPLUG_CPU=y:
WARNING: vmlinux.o(.text+0x1128d): Section mismatch: reference to .init.text.1:calibrate_delay (between 'check_cx686_slop' and 'set_cx86_reorder')
WARNING: vmlinux.o(.text+0x25102): Section mismatch: reference to .init.text.1:calibrate_delay (between 'smp_callin' and 'cpu_coregroup_map')
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Christian Zankel <chris@zankel.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.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>
NR_OPEN (historically set to 1024*1024) actually forbids processes to open
more than 1024*1024 handles.
Unfortunatly some production servers hit the not so 'ridiculously high
value' of 1024*1024 file descriptors per process.
Changing NR_OPEN is not considered safe because of vmalloc space potential
exhaust.
This patch introduces a new sysctl (/proc/sys/fs/nr_open) wich defaults to
1024*1024, so that admins can decide to change this limit if their workload
needs it.
[akpm@linux-foundation.org: export it for sparc64]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the new timerfd API as it is implemented by the following patch:
int timerfd_create(int clockid, int flags);
int timerfd_settime(int ufd, int flags,
const struct itimerspec *utmr,
struct itimerspec *otmr);
int timerfd_gettime(int ufd, struct itimerspec *otmr);
The timerfd_create() API creates an un-programmed timerfd fd. The "clockid"
parameter can be either CLOCK_MONOTONIC or CLOCK_REALTIME.
The timerfd_settime() API give new settings by the timerfd fd, by optionally
retrieving the previous expiration time (in case the "otmr" parameter is not
NULL).
The time value specified in "utmr" is absolute, if the TFD_TIMER_ABSTIME bit
is set in the "flags" parameter. Otherwise it's a relative time.
The timerfd_gettime() API returns the next expiration time of the timer, or
{0, 0} if the timerfd has not been set yet.
Like the previous timerfd API implementation, read(2) and poll(2) are
supported (with the same interface). Here's a simple test program I used to
exercise the new timerfd APIs:
http://www.xmailserver.org/timerfd-test2.c
[akpm@linux-foundation.org: coding-style cleanups]
[akpm@linux-foundation.org: fix ia64 build]
[akpm@linux-foundation.org: fix m68k build]
[akpm@linux-foundation.org: fix mips build]
[akpm@linux-foundation.org: fix alpha, arm, blackfin, cris, m68k, s390, sparc and sparc64 builds]
[heiko.carstens@de.ibm.com: fix s390]
[akpm@linux-foundation.org: fix powerpc build]
[akpm@linux-foundation.org: fix sparc64 more]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 312b1485fb made __INIT_REFOK expand
into .section .section ".ref.text", "ax". Since the assembler doesn't
tolerate stuttering in the source that broke all MIPS builds.
Since with this change Sam downgraded __INIT_REFOK the best fix is to
get replace it by the modern days operator. With MIPS the only user
of __INIT_REFOK and __INITDATA_REFOK (which was equally broken) being
unused anyway these can be deleted but that's subject of a separate
commit.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The timer code always calls the clock_event_device set_net_event and
set_mode methods with interrupts disabled, so no need to use
spin_lock_irqsave / spin_unlock_irqrestore for those.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by:Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds IDs for new Au1200 variants: Au1210 and Au1250.
They are essentially identical to the Au1200 except for the Au1210
which has a different SoC-ID in the PRId register [bits 31:24].
The Au1250 is a "Au1200 V0.2".
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move registration into the actual platform code instead of making a
desparate attempt at sharing the hand full of likes of code in pcspeaker.c.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This complements the generic R4000/R4400 errata workaround code and adds
bits for the daddiu problem. In most places it just modifies handwritten
assembly code so that the assembler is allowed to use a temporary register
as daddiu may now be treated as a macro that expands to a sequence of li
and daddu. It is the AT register or, where AT is unavailable or used
explicitly for another purpose, an explicitly-named register is selected,
using the .set at=<reg> feature added recently to gas. This feature is
only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the
workaround remains disabled, the required version of binutils stays
unchanged.
Similarly, daddiu instructions put in branch delay slots in noreorder
fragments are now taken out of them and the assembler is allowed to
reorder them itself as possible (which it does making the whole idea of
scheduling them into delay slots manually questionable).
Also in the very few places where such a simple conversion was not
possible, a handcoded longer sequence is implemented.
Other than that there are changes to code responsible for building the
TLB fault and page clear/copy handlers to avoid daddiu as appropriate.
These are only effective if the erratum is verified to be present at the
run time.
Finally there is a trivial update to __delay(), because it uses daddiu in
a branch delay slot.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is the gereric part of R4000/R4400 errata workarounds. They include
compiler and assembler support as well as some source code modifications
to address the problems with some combinations of multiply/divide+shift
instructions as well as the daddi and daddiu instructions.
Changes included are as follows:
1. New Kconfig options to select workarounds by platforms as necessary.
2. Arch top-level Makefile to pass necessary options to the compiler; also
incompatible configurations are detected (-mno-sym32 unsupported as
horribly intrusive for little gain).
3. Bug detection updated and shuffled -- the multiply/divide+shift problem
is lethal enough that if not worked around it makes the kernel crash in
time_init() because of a division by zero; the daddiu erratum might
also trigger early potentially, though I have not observed it. On the
other hand the daddi detection code requires the exception subsystem to
have been initialised (and is there mainly for information).
4. r4k_daddiu_bug() added so that the existence of the erratum can be
queried by code at the run time as necessary; useful for generated code
like TLB fault and copy/clear page handlers.
5. __udelay() updated as it uses multiplication in inline assembly.
Note that -mdaddi requires modified toolchain (which has been maintained
by myself and available from my site for ~4years now -- versions covered
are GCC 2.95.4 - 4.1.2 and binutils from 2.13 onwards). The -mfix-r4000
and -mfix-r4400 have been standard for a while though.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch consolidate all definitions of .init.text, .init.data
and .exit.text, .exit.data section definitions in
the generic vmlinux.lds.h.
This is a preparational patch - alone it does not buy
us much good.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Replace all lock_cpu_hotplug/unlock_cpu_hotplug from the kernel and use
get_online_cpus and put_online_cpus instead as it highlights the
refcount semantics in these operations.
The new API guarantees protection against the cpu-hotplug operation, but
it doesn't guarantee serialized access to any of the local data
structures. Hence the changes needs to be reviewed.
In case of pseries_add_processor/pseries_remove_processor, use
cpu_maps_update_begin()/cpu_maps_update_done() as we're modifying the
cpu_present_map there.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
All kobjects require a dynamically allocated name now. We no longer
need to keep track if the name is statically assigned, we can just
unconditionally free() all kobject names on cleanup.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This seems as reasonable assumption and gets some SNI machines to work
which currently must rely on the cp0 counter as clocksource.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Frank Rowand <frank.rowand@am.sony.com> reports:
> In linux-2.6.24-rc4 the Toshiba RBTX4927 hangs on boot.
>
> The cause is that plat_time_init() from arch/mips/tx4927/common/
> tx4927_setup.c does not override the __weak plat_time_init() from
> arch/mips/kernel/time.c. This is due to a compiler bug in gcc 4.1.1. The
> bug is reported to not exist in earlier versions of gcc, and to be fixed in
> 4.1.2. The problem is that the __weak plat_time_init() is empty and thus
> gets optimized out of existence (thus the linker is never given the option
> to replace the __weak function).
[ He meant the call to plat_time_init() from time_init() gets optimized away ]
> For more info on the gcc bug see
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27781
>
> The attached patch is one workaround. Another possible workaround
[ His patch adds -fno-unit-at-a-time for time.c ]
> would be to change the __weak plat_time_init() to be a non-empty
> function.
The __weak definition of plat_time_init was only ever meant to be a
migration helper to keep platforms that don't have a plat_time_init
compiling. A few greps says that all platforms now supply their own
plat_time_init() so the weak definition is no longer needed. So I
instead delete it.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Sibyte SOCs only have 32-bit PCI. Due to the sparse use of the address
space only the first 1GB of memory is mapped at physical addresses
below 1GB. If a system has more than 1GB of memory 32-bit DMA will
not be able to reach all of it.
For now this patch is good enough to keep Sibyte users happy but it seems
eventually something like swiotlb will be needed for Sibyte.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In particular as-is it's not suited for multicore and mutiprocessors
systems where there is on guarantee that the counter are synchronized
or running from the same clock at all. This broke Sibyte and probably
others since the "[MIPS] Handle R4000/R4400 mfc0 from count register."
commit.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The R4000 and R4400 have an errata where if the cp0 count register is read
in the exact moment when it matches the compare register no interrupt will
be generated.
This bug may be triggered if the cp0 count register is being used as
clocksource and the compare interrupt as clockevent. So a simple
workaround is to avoid using the compare for both facilities on the
affected CPUs.
This is different from the workaround suggested in the old errata documents;
at some opportunity probably the official version should be implemented
and tested. Another thing to find out is which processor versions
exactly are affected. I only have errata documents upto R4400 V3.0
available so for the moment the code treats all R4000 and R4400 as broken.
This is potencially a problem for some machines that have no other decent
clocksource available; this workaround will cause them to fall back to
another clocksource, worst case the "jiffies" source.
This matters to any sort of device that is wired to one of the CPU
interrupt pins on an SMP system. Typically the scenario is most easily
triggered with the count/compare timer interrupt where the same interrupt
number and thus irq_desc is used on each processor.
CPU A CPU B
do_IRQ()
generic_handle_irq()
handle_level_irq()
spin_lock(desc_lock)
set IRQ_INPROGRESS
spin_unlock(desc_lock)
do_IRQ()
generic_handle_irq()
handle_level_irq()
spin_lock(desc_lock)
IRQ_INPROGRESS set => bail out
spin_lock(desc_lock)
clear IRQ_INPROGRESS
spin_unlock(desc_lock)
In case of the cp0 compare interrupt this means the interrupt will be
acked and not handled or re-armed on CPU b, so there won't be any timer
interrupt until the count register wraps around.
With kernels 2.6.20 ... 2.6.23 we usually were lucky that things were just
working right on VSMP because the count registers are synchronized on
bootup so it takes something that disables interrupts for a long time on
one processor to trigger this one.
For scenarios where an interrupt is multicasted or broadcasted over several
CPUs the existing code was safe and the fix will break it. There is no
way to know in the interrupt controller code because it is abstracted from
the platform code. I think we do not have such a setup currently, so this
should be ok.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matthew Wilcox