It acts exactly like a regular 'cond_resched()', but will not get
optimized away when CONFIG_PREEMPT is set.
Normal kernel code is already preemptable in the presense of
CONFIG_PREEMPT, so cond_resched() is optimized away (see commit
02b67cc3ba "sched: do not do
cond_resched() when CONFIG_PREEMPT").
But when wanting to conditionally reschedule while holding a lock, you
need to use "cond_sched_lock(lock)", and the new function is the BKL
equivalent of that.
Also make fs/locks.c use it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
So, forever, we've had this ptrace_signal_deliver implementation
which tries to handle all of the nasties that can occur when the
debugger looks at a process about to take a signal. It's meant
to address all of these issues inside of the kernel so that the
debugger need not be mindful of such things.
Problem is, this doesn't work.
The idea was that we should do the syscall restart business first, so
that the debugger captures that state. Otherwise, if the debugger for
example saves the child's state, makes the child execute something
else, then restores the saved state, we won't handle the syscall
restart properly because we lose the "we're in a syscall" state.
The code here worked for most cases, but if the debugger actually
passes the signal through to the child unaltered, it's possible that
we would do a syscall restart when we shouldn't have.
In particular this breaks the case of debugging a process under a gdb
which is being debugged by yet another gdb. gdb uses sigsuspend
to wait for SIGCHLD of the inferior, but if gdb itself is being
debugged by a top-level gdb we get a ptrace_stop(). The top-level gdb
does a PTRACE_CONT with SIGCHLD to let the inferior gdb see the
signal. But ptrace_signal_deliver() assumed the debugger would cancel
out the signal and therefore did a syscall restart, because the return
error was ERESTARTNOHAND.
Fix this by simply making ptrace_signal_deliver() a nop, and providing
a way for the debugger to control system call restarting properly:
1) Report a "in syscall" software bit in regs->{tstate,psr}.
It is set early on in trap entry to a system call and is fully
visible to the debugger via ptrace() and regsets.
2) Test this bit right before doing a syscall restart. We have
to do a final recheck right after get_signal_to_deliver() in
case the debugger cleared the bit during ptrace_stop().
3) Clear the bit in trap return so we don't accidently try to set
that bit in the real register.
As a result we also get a ptrace_{is,clear}_syscall() for sparc32 just
like sparc64 has.
M68K has this same exact bug, and is now the only other user of the
ptrace_signal_deliver hook. It needs to be fixed in the same exact
way as sparc.
Signed-off-by: David S. Miller <davem@davemloft.net>
Forever we had a PTRACE_SUNOS_DETACH which was unconditionally
recognized, regardless of the personality of the process.
Unfortunately, this value is what ended up in the GLIBC sys/ptrace.h
header file on sparc as PTRACE_DETACH and PT_DETACH.
So continue to recognize this old value. Luckily, it doesn't conflict
with anything we actually care about.
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86:
x86: rdc: leds build/config fix
x86: sysfs cpu?/topology is empty in 2.6.25 (32-bit Intel system)
x86: revert commit 709f744 ("x86: bitops asm constraint fixes")
x86: restrict keyboard io ports reservation to make ipmi driver work
x86: fix fpu restore from sig return
x86: remove spew print out about bus to node mapping
x86: revert printk format warning change which is for linux-next
x86: cleanup PAT cpu validation
x86: geode: define geode_has_vsa2() even if CONFIG_MGEODE_LX is not set
x86: GEODE: cache results from geode_has_vsa2() and uninline
x86: revert geode config dependency
The generic semaphore rewrite had a huge performance regression on AIM7
(and potentially other BKL-heavy benchmarks) because the generic
semaphores had been rewritten to be simple to understand and fair. The
latter, in particular, turns a semaphore-based BKL implementation into a
mess of scheduling.
The attempt to fix the performance regression failed miserably (see the
previous commit 00b41ec261 'Revert
"semaphore: fix"'), and so for now the simple and sane approach is to
instead just go back to the old spinlock-based BKL implementation that
never had any issues like this.
This patch also has the advantage of being reported to fix the
regression completely according to Yanmin Zhang, unlike the semaphore
hack which still left a couple percentage point regression.
As a spinlock, the BKL obviously has the potential to be a latency
issue, but it's not really any different from any other spinlock in that
respect. We do want to get rid of the BKL asap, but that has been the
plan for several years.
These days, the biggest users are in the tty layer (open/release in
particular) and Alan holds out some hope:
"tty release is probably a few months away from getting cured - I'm
afraid it will almost certainly be the very last user of the BKL in
tty to get fixed as it depends on everything else being sanely locked."
so while we're not there yet, we do have a plan of action.
Tested-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Alexander Viro <viro@ftp.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit bf726eab37, as it has
been reported to cause a regression with processes stuck in __down(),
apparently because some missing wakeup.
Quoth Sven Wegener:
"I'm currently investigating a regression that has showed up with my
last git pull yesterday. Bisecting the commits showed bf726e
"semaphore: fix" to be the culprit, reverting it fixed the issue.
Symptoms: During heavy filesystem usage (e.g. a kernel compile) I get
several compiler processes in uninterruptible sleep, blocking all i/o
on the filesystem. System is an Intel Core 2 Quad running a 64bit
kernel and userspace. Filesystem is xfs on top of lvm. See below for
the output of sysrq-w."
See
http://lkml.org/lkml/2008/5/10/45
for full report.
In the meantime, we can just fix the BKL performance regression by
reverting back to the good old BKL spinlock implementation instead,
since any sleeping lock will generally perform badly, especially if it
tries to be fair.
Reported-by: Sven Wegener <sven.wegener@stealer.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It actually makes much more sense there, and we do tend to need it for
non-RCU usage too. Moving it to <linux/compiler.h> will allow some
other cases that have open-coded the same logic to use the same helper
function that RCU has used.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
select NEW_LEDS for now until the Kconfig dependencies have been
fixed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
System topology on intel based system needs to be exported
for non-numa case as well.
All parts of asm-i386/topology.h has come under
#ifdef CONFIG_NUMA after the merge to asm-x86/topology.h
/sys/devices/system/cpu/cpu?/topology/* is populated based on
ENABLE_TOPO_DEFINES
The sysfs cpu topology is not being populated on my dual socket
dual core xeon 5160 processor based (x86 32 bit) system.
CONFIG_NUMA is not set in my case yet the topology is relevant
and useful.
irqbalance daemon application depends on topology to build the
cpus and package list and it fails on Fedora9 beta since the
sysfs topology was not being populated in the 2.6.25 kernel.
I am not sure if it was intentional to not define ENABLE_TOPO_DEFINES
for non-numa systems.
This fix has been tested on the above mentioned dual core, dual socket
system.
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
709f744 causes my computer to freeze during the start up of X and my
login manger (GDM). It gets to the point where it has shown the default
X mouse cursor logo (a big X / cross) and does not respond to anything
from that point on.
This worked fine before 709f744, and it works fine with 709f744
reverted on top of Linus' current tree (f74d505). The revert had
conflicts, as far as I can tell due to white space changes. The diff I
ended up with is below.
It is 100% reproducible.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On some of our (single board computer) boards (x86) we are using an
IPMI controller that uses I/O ports 0x62 and 0x66 for a KCS (keyboard
controller style) IPMI system interface.
Trying to load the openipmi driver fails, because the ports
(0x62/0x66) are reserved for keyboard. keyboard reserves the full
range 0x60-0x6F while it doesn't need to.
Reserve only ports 0x60 and 0x64 for the legacy PS/2 i8042 keyboad
controller instead of 0x60-0x6F to allow the openipmi driver to work.
[ tglx: added 64bit fixup ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If the task never used fpu, initialize the fpu before restoring the FP
state from the signal handler context. This will allocate the fpu
state, if the task never needed it before.
Reported-and-bisected-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Eric Sesterhenn <snakebyte@gmx.de>
Cc: Frederik Deweerdt <deweerdt@free.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Jeff Garzik pointed out that this printout is not needed.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
A lot of stuff in spitz/akita/etc. depends on corgi_ssp to be initialised
early. However corgi_ssp initialisation fails, because at that time pxa*-ssp
devices don't have drivers. Move ssp earlier in the makefile so they are
registered before corgi-ssp.
Also move sleep/suspend and cpu-freq to more logical places
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This behavior differs across multiple controllers, so we cannot use
common logic for all controllers.
Revert back to the basic common behavior, and specific drivers will
be updated from here to take into account the unusual Status return
values.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/blackfin-2.6: (21 commits)
Blackfin Serial Driver: abstract away DLAB differences into header
Blackfin Serial Driver: macro away the IER differences between processors
[Blackfin] arch: remove useless IRQ_SW_INT defines
[Blackfin] arch: protect linux/usb/musb.h include until the driver gets mainlined
[Blackfin] arch: protect linux/usb/isp1362.h include until the driver gets mainlined
[Blackfin] arch: add EBIU supporting for BF54x EZKIT SMSC LAN911x/LAN921x families embedded ethernet driver
[Blackfin] arch: Set spi flash partition on bf527 as like bf548.
[Blackfin] arch: fix bug - Remove module will not free L1 memory used
[Blackfin] arch: fix wrong header name in comment
[Blackfin] arch: Fix BUG - spi flash on bf527 ezkit would fail at mount
[Blackfin] arch: add twi_lcd and twi_keypad i2c board info to bf527-ezkit
[Blackfin] arch: Add physmap partition for BF527-EZkit
[Blackfin] arch: fix gdb testing regression
[Blackfin] arch: disable single stepping when delivering a signal
[Blackfin] arch: Delete unused (copied from m68k) entries in asm-offsets.c.
[Blackfin] arch: In the double fault handler, set up the PT_RETI slot
[Blackfin] arch: Support for CPU_FREQ and NOHZ
[Blackfin] arch: Functional power management support: Add CPU and platform voltage scaling support
[Blackfin] arch: fix bug - breaking the atomic sections code.
[Blackfin] arch: Equalize include files: Add VR_CTL masks
...
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] fix build warning
[CIFS] Fixed build warning in is_ip
[CIFS] cleanup cifsd completion
[CIFS] Remove over-indented code in find_unc().
[CIFS] fix typo
[CIFS] Remove duplicate call to mode_to_acl
[CIFS] convert usage of implicit booleans to bool
[CIFS] fixed compatibility issue with samba refferal request
[CIFS] Fix statfs formatting
[CIFS] Adds to dns_resolver checking if the server name is an IP addr and skipping upcall in this case.
[CIFS] Fix spelling mistake
[CIFS] Update cifs version number
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (37 commits)
SH: catch negative denormal_subf1() retval in denormal_add()
sh: Fix DMAC base address for SH7709S
sh: update smc91x platform data for se7206.
sh: Stub in cpu_to_node() and friends for NUMA build.
sh: intc register modify fix
sh: no high level trigger on some sh3 cpus
sh: clean up sh7710 and sh7720 intc tables
sh: add interrupt ack code to sh3
sh: unify external irq pin code for sh3
sh-sci: avoid writing to nonexistent registers
sh-sci: sh7722 lacks scsptr registers
sh-sci: improve sh7722 support
sh: reset hardware from early printk
sh: drain and wait for early printk
sh: use sci_out() for early printk
sh: add memory resources to /proc/iomem
sh: add kernel bss resource
sh: fix sh7705 interrupt vector typo
sh: update smc91x platform data for se7722
sh: update smc91x platform data for MigoR
...
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (23 commits)
[POWERPC] Remove leftover printk in isa-bridge.c
[POWERPC] Remove duplicate #include
[POWERPC] Initialize lockdep earlier
[POWERPC] Document when printk is useable
[POWERPC] Fix bogus paca->_current initialization
[POWERPC] Fix of_i2c include for module compilation
[POWERPC] Make default cputable entries reflect selected CPU family
[POWERPC] spufs: lockdep annotations for spufs_dir_close
[POWERPC] spufs: don't requeue victim contex in find_victim if it's not in spu_run
[POWERPC] 4xx: Fix PCI mem in sequoia DTS
[POWERPC] 4xx: Add endpoint support to 4xx PCIe driver
[POWERPC] 4xx: Fix problem with new TLB storage attibute fields on 440x6 core
[POWERPC] spufs: spu_create should send inotify IM_CREATE event
[POWERPC] spufs: handle faults while the context switch pending flag is set
[POWERPC] spufs: fix concurrent delivery of class 0 & 1 exceptions
[POWERPC] spufs: try to route SPU interrupts to local node
[POWERPC] spufs: set SPU_CONTEXT_SWITCH_PENDING before synchronising SPU irqs
[POWERPC] spufs: don't acquire state_mutex interruptible while performing callback
[POWERPC] spufs: update master runcntl with context lock held
[POWERPC] spufs: fix post-stopped update of MFC_CNTL register
...
m32r can use the generic sys_pipe implementation.
The current sys_pipe implementation on m32r only differes from the
generic one by passing a lot of additional unused registers to sys_pipe.
Reviewed and tested by Hirokazu Takata.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Linus found a logic bug: we ignore the version number in a module's
vermagic string if we have CONFIG_MODVERSIONS set, but modversions
also lets through a module with no __versions section for modprobe
--force (with tainting, but still).
We should only ignore the start of the vermagic string if the module
actually *has* crcs to check. Rather than (say) having an
entertaining hissy fit and creating a config option to work around the
buggy code.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We allow missing __versions sections, because modprobe --force strips
it. It makes less sense to allow sections where there's no version
for a specific symbol the module uses, so disallow that.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Don't allow a module built without versions altogether to be inserted
into a kernel which expects modversions.
modprobe --force will strip vermagic as well as modversions, so it
won't be effected, but this will make sure that a
non-CONFIG_MODVERSIONS module won't be accidentally inserted into a
CONFIG_MODVERSIONS kernel.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch cleans up Orion's addr-map.c a bit after all peripheral
window programming code has been moved out into the relevant drivers.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Pass the Orion TCLK tick rate into the ethernet driver.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Make the Orion 5x platform code use the mbus window handling code
that's in the mv643xx_eth driver, instead of programming the GigE
block's mbus window registers by hand.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
'ix' is unsigned but denormal_subf1() may return a negative int.
Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This printk() appears twice in the same function. Only the latter one
in the inval_range: section appears to be legitimate.
Signed-off-by: Nate Case <ncase@xes-inc.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove duplicate #include of <asm/prom.h> in
arch/powerpc/kernel/btext.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This moves lockdep_init() to before udbg_early_init() as the later
can call things that acquire spinlocks etc... This also makes printk
safer to use earlier.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When debugging early boot problems, it's common to sprinkle printk's
all over the place. However, on 64-bit powerpc, this can lead to
memory corruption if done too early due to the PACA pointer and
lockdep core not being initialized.
This adds some comments to early_setup() that document when it is
safe to do so in order to save time for whoever has to debug that
stuff next.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When doing lockdep, I had two patches to initialize paca->_current
early, one bogus, and one correct. Unfortunately both got merged
as the bad one ended up being part of the main lockdep patch by
mistake. This causes memory corruption at boot. This removes
the offending code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove #ifdef CONFIG_OF_I2C as this breaks module compilation.
Drivers using this header should depend on OF_I2C anyways, so
there's no need to make this conditional.
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Changes the cputable so that various CPU families that have an exclusive
CONFIG_ option have a more sensible default entry to use if the specific
processor hasn't been identified.
This makes the kernel more generally useful when booted on an unknown
PVR for things like new 4xx variants.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On SH7709S, DMAC can be found at 0xa4000020 (as with most of
the other sh3 cpu subtypes).
Split out definition of DMAC base address from definitions of
DMTE irqs.
Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch increases the headroom TIPC reserves in each sk_buff
to accommodate the largest possible link level device header.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
