Commit Graph

5025 Commits

Author SHA1 Message Date
Michael Ellerman
496b7a5159 [PATCH] powerpc: Fix bug in spinup of renumbered secondary threads
If the logical and physical cpu ids of a secondary thread don't match, we will
fail to spin the thread up on pSeries machines due to a bug in pseries/smp.c

We call the RTAS "start-cpu" method with the physical cpu id, the address of
pSeries_secondary_smp_init and the value to pass that function in r3. Currently
we pass "lcpu", the logical cpu id, but pSeries_secondary_smp_init expects
the physical cpu id in r3.

We should be passing pcpu instead.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-20 12:03:37 +11:00
Michael Ellerman
8fca92705e [PATCH] powerpc: Make UP -> SMP kexec work again
For UP to SMP kexec to work we need to jump into pSeries_secondary_smp_init
event on a UP + KEXEC kernel. The secondary cpus will not find their hw_cpu_id
in the paca and so they'll jump into kexec_wait, ready for a kexec.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-20 12:03:36 +11:00
Michael Ellerman
f018b36f3e [PATCH] powerpc: Don't start secondary CPUs in a UP && KEXEC kernel
Because smp_release_cpus() is built for SMP || KEXEC, it's not safe to
unconditionally call it from setup_system(). On a UP && KEXEC kernel we'll
start up the secondary CPUs which will then go beserk and we die.

Simple fix is to conditionally call smp_release_cpus() in setup_system(). With
that in place we don't need the dummy definition of smp_release_cpus() because
all call sites are #ifdef'ed either SMP or KEXEC.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-20 12:03:34 +11:00
Olof Johansson
2b9a32edba [PATCH] powerpc: Fix OOPS in lparcfg on G5
Fallback gracefully when reading /proc/ppc64/lparcfg when the /rtas
device node can't be found.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-20 10:44:34 +11:00
Olaf Hering
0728a2f99e [PATCH] powerpc: remove duplicate exports
A few symbols are exported twice, remove them from ppc_ksyms.c
Remove users of sys_ctrler in arch/ppc/

WARNING: vmlinux: duplicate symbol '__delay' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol '__up' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol '__down' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol '__down_interruptible' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'sys_ctrler' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strncat' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strncmp' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strchr' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strrchr' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strnlen' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strpbrk' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'memscan' previous definition was in vmlinux
WARNING: vmlinux: duplicate symbol 'strstr' previous definition was in vmlinux

Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-20 10:44:31 +11:00
Paul Mackerras
092b8f3488 powerpc: Keep xtime and gettimeofday in sync
This fixes a regression which was introduced by moving ppc32 to use
the same sort of lockless gettimeofday as ppc64 has been using for
some time.  This involves getting the timebase and performing some
simple arithmetic to convert it to seconds and microseconds.  However,
the factor and offset used there weren't being updated when NTP
varied the tick length using adjtimex.  64-bit didn't notice the
problem because it had a hook in the 32-bit adjtimex compat routine
that attempted to work out what the generic timekeeping code would
do and alter the factor and offset to match.  However, that code
was very complex and it wasn't clear that it still matched what the
generic code would do.

Now we use the generic current_tick_length() routine that was recently
added to check that the current tick will be as long as we expect; if
not we recompute the factor and offset.  This keeps gettimeofday and
xtime in sync.  In addition we check that gettimeofday hasn't got ahead
of xtime on each timer interrupt; if it has, we resync.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-20 10:38:56 +11:00
Tim Hockin
9ff4ced467 [PATCH] Remove KERN_INFO from middle of printk line
Don't print KERN_INFO in the middle of a printk line.
	printk(KERN_INFO "OEM ID: %s ",str);
is just above this. This is already fixed up in i386 copy.

Signed-off-by: Martin J. Bligh <mbligh@google.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:27 -08:00
Heiko Carstens
ed3d021b82 [PATCH] s390: sys32_fstatat -> sys32_fstatat64
Just rename the compat system call to keep the name consistent with all the
other *64 compat system calls.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:27 -08:00
Heiko Carstens
54330456b2 [PATCH] s390: smp initialization speed
The last changes that introduced the additional_cpus command line parameter
also introduced a regression regarding smp initialization speed.  In
smp_setup_cpu_possible_map() cpu_present_map is set to the same value as
cpu_possible_map.  Especially that means that bits in the present map will be
set for cpus that are not present.  This will cause a slow down in the initial
cpu_up() loop in smp_init() since trying to take cpus online that aren't
present takes a while.

Fix this by setting only bits for present cpus in cpu_present_map and set
cpu_present_map to cpu_possible_map in smp_cpus_done().

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:27 -08:00
Heiko Carstens
37a3302618 [PATCH] s390: possible_cpus parameter
Introduce possible_cpus command line option.  Hard sets the number of bits set
in cpu_possible_map.  Unlike the additional_cpus parameter this one guarantees
that num_possible_cpus() will stay constant even if the system gets rebooted
and a different number of cpus are present at startup.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:27 -08:00
Heiko Carstens
255acee706 [PATCH] s390: additional_cpus parameter
Introduce additional_cpus command line option.  By default no additional cpu
can be attached to the system anymore.  Only the cpus present at IPL time can
be switched on/off.  If it is desired that additional cpus can be attached to
the system the maximum number of additional cpus needs to be specified with
this option.

This change is necessary in order to limit the waste of per_cpu data
structures.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:26 -08:00
Heiko Carstens
1fca251f36 [PATCH] s390: fix preempt_count of idle thread with cpu hotplug
Set preempt_count of idle_thread to zero before switching off cpu.  Otherwise
the preempt_count will be wrong if the cpu is switched on again since the
thread will be reused.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:26 -08:00
Ingo Molnar
4bbf39c29b [PATCH] Introduce CONFIG_DEFAULT_MIGRATION_COST
Heiko Carstens <heiko.carstens@de.ibm.com> wrote:

  The boot sequence on s390 sometimes takes ages and we spend a very long
  time (up to one or two minutes) in calibrate_migration_costs.  The time
  spent there differs from boot to boot.  Also the calculated costs differ
  a lot.  I've seen differences by up to a factor of 15 (yes, factor not
  percent).  Also I doubt that making these measurements make much sense on
  a completely virtualized architecture where you cannot tell how much cpu
  time you will get anyway.

So introduce the CONFIG_DEFAULT_MIGRATION_COST method for an architecture
to set the scheduler migration costs.  This turns off automatic detection
of migration costs.  Makes sense on virtual platforms, where migration
costs are hard to measure accurately.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:26 -08:00
Adrian Bunk
05efc67d10 [PATCH] arch/sh/Kconfig: fix the ISA_DMA_API dependencies
Jean-Luc Leger <reiga@dspnet.fr.eu.org> found this obvious typo.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 13:59:26 -08:00
Linus Torvalds
759b650f54 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 2006-02-17 08:16:35 -08:00
Linus Torvalds
a5222049f3 Merge master.kernel.org:/home/rmk/linux-2.6-arm 2006-02-17 08:13:11 -08:00
Andi Kleen
2aed711a39 [PATCH] x86_64: Always pass full number of nodes to NUMA hash computation
Previously the numa hash code would be confused by holes in the node space
and stop early. This is the first part of the fix for the non boot issue
with empty nodes on Opterons.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:41 -08:00
Andi Kleen
fdb9df9424 [PATCH] x86_64: Relax SRAT covers all memory check a bit
Code was refusing good SRATs because about 12K got lost somewhere.
Allow less than 1MB of difference before rejecting it.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:41 -08:00
Andi Kleen
6574ffd74b [PATCH] x86_64: Resolve the RIP of an early exception using kallsyms
But do it after everything else to risk less from recursive
crashes.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Andi Kleen
7fd67843b9 [PATCH] x86_64: Disable tsc when apicpmtimer is active
Otherwise it has no effect anyways.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Andi Kleen
ab68805955 [PATCH] x86_64: Don't enable ATI apicmaintimer workaround when the machine has C2 or C3
Many laptops have problems with ticking the local APIC timer in C2/C3.
The code added earlier to use it by default on ATI didn't really work
for them. Don't enable it when the system supports C2/C3.

This doesn't fix the problem fully, but at least it's not worse than before.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Andi Kleen
2391c4b594 [PATCH] x86_64: Don't call do_exit with interrupts disabled after IRET exception
This caused a sigreturn with bad argument on a preemptible kernel
to complain with

Debug: sleeping function called from invalid context at /home/lsrc/quilt/linux/include/linux/rwsem.h:43
in_atomic():0, irqs_disabled():1

Call Trace: {__might_sleep+190} {profile_task_exit+21}
       {__do_exit+34} {do_wait+0}

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Andi Kleen
a62eaf151d [PATCH] x86_64: Add boot option to disable randomized mappings and cleanup
AMD SimNow!'s JIT doesn't like them at all in the guest. For distribution
installation it's easiest if it's a boot time option.

Also I moved the variable to a more appropiate place and make
it independent from sysctl

And marked __read_mostly which it is.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Jan Beulich
99019e9199 [PATCH] x86_64: make touch_nmi_watchdog() not touch impossible cpus' private data
Along with that, also suppress the memory touching altogether when the
watchdog is not running, to eliminate needless crosstalk. Plus ad a call
to it to make things consistent (one could also consider removing the call
in enable_timer_nmi_watchdog()).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Andi Kleen
e4444d1a30 [PATCH] x86_64: Update defconfig
... and enable 1394 by default.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-17 08:00:40 -08:00
Nicolas Pitre
6c0fa49b18 [ARM] 3338/1: old ABI compat: sys_socketcall
Patch from Nicolas Pitre

Commit 99595d0237 forgot to intercept
sys_socketcall as well.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-16 22:36:13 +00:00
Martin Michlmayr
3dfaf7a68e [ARM] 3337/1: Fix NSLU2 flash support according to window size configuration patch
Patch from Martin Michlmayr

ARM patch 3226/1 (IXP4xx runtime expansion bus window size configuration)
forgot to update mach-ixp4xx/nslu2-setup.c which leads to the following
compilation error.  Update NSLU2 flash support following patch 3226/1.

  CC      arch/arm/mach-ixp4xx/nslu2-setup.o
arch/arm/mach-ixp4xx/nslu2-setup.c:30: error: NSLU2_FLASH_BASE undeclared here (not in a function)
arch/arm/mach-ixp4xx/nslu2-setup.c:31: error: NSLU2_FLASH_SIZE undeclared here (not in a function)
make[1]: *** [arch/arm/mach-ixp4xx/nslu2-setup.o] Error 1
make: *** [arch/arm/mach-ixp4xx] Error 2

Signed-off-by: Martin Michlmayr <tbm@cyrius.com>

---

 nslu2-setup.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-16 22:36:12 +00:00
Ashok Raj
8f8b1138fc [IA64] Count disabled cpus as potential hot-pluggable CPUs
Minor updates to earlier patch.
- Added to documentation to add ia64 as well.
- Minor clarification on how to use disabled cpus
- used plain max instead of max_t per Andew Morton.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-16 14:10:50 -08:00
Jack Steiner
6f6d75825d [IA64] Missing check for TIF_WORK if trace/audit enabled
It appears that if auditing is enabled, the kernel fails to
check for pending signals before returning to user mode.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Acked-by: Ken Chen <kenneth.w.chen@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-16 10:20:08 -08:00
Russell King
7bbb794031 [ARM] Fix SMP initialisation oops
A change to the SMP initialisation caused the following oops:

 CPU1: Booted secondary processor
 CPU1: D VIPT write-back cache
 CPU1: I cache: 32768 bytes, associativity 4, 32 byte lines, 256 sets
 CPU1: D cache: 32768 bytes, associativity 4, 32 byte lines, 256 sets
 <7>Calibrating delay loop... 83.14 BogoMIPS (lpj=415744)
 <1>Unable to handle kernel NULL pointer dereference at virtual address 0000001c
 ...
 PC is at enqueue_task+0x1c/0x64
 LR is at activate_task+0xcc/0xe4

SMP initialisation now requires cpu_possible_map to be initialised in
setup_arch().  Move this from smp_prepare_cpus() to smp_init_cpus()
and call it from our setup_arch() if CONFIG_SMP is enabled.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-16 11:08:09 +00:00
Daniel Yeisley
d1db4ec86c [PATCH] x86_64: early initialization of cpu_to_node
The early initialization of cpu_to_node code as it is now only updates the
cpu_to_node array, and does not update cpu_pda()->nodemember.  This will
cause numa_node_id() to return 0 on systems where CPU 0 is not on Node 0.
This leads to a kernel panic in slab.c.

I've tested the patch below on a 16 processor x86_64 ES7000-600 server, and
no longer see the panic I saw with the original 2.6.16-rc3.

Signed-off-by: Dan Yeisley <dan.yeisley@unisys.com>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-15 15:32:22 -08:00
Tony Luck
72166c35f0 Pull fix-cpu-possible-map into release branch 2006-02-15 15:17:57 -08:00
Horms
b05de01ae1 [IA64] support panic_on_oops sysctl
Trivial port of this feature from i386
As it stands, panic_on_oops but does nothing on ia64

Signed-Off-By: Horms <horms@verge.net.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 15:16:50 -08:00
hawkes@sgi.com
defbb2c929 [IA64] ia64: simplify and fix udelay()
The original ia64 udelay() was simple, but flawed for platforms without
synchronized ITCs:  a preemption and migration to another CPU during the
while-loop likely resulted in too-early termination or very, very
lengthy looping.

The first fix (now in 2.6.15) broke the delay loop into smaller,
non-preemptible chunks, reenabling preemption between the chunks.  This
fix is flawed in that the total udelay is computed to be the sum of just
the non-premptible while-loop pieces, i.e., not counting the time spent
in the interim preemptible periods.  If an interrupt or a migration
occurs during one of these interim periods, then that time is invisible
and only serves to lengthen the effective udelay().

This new fix backs out the current flawed fix and returns to a simple
udelay(), fully preemptible and interruptible.  It implements two simple
alternative udelay() routines:  one a default generic version that uses
ia64_get_itc(), and the other an sn-specific version that uses that
platform's RTC.

Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:37:04 -08:00
Dean Nelson
4c2cd96696 [IA64-SGI] enforce proper ordering of callouts by XPC
Fix XPC so that it does not deliver any messages until the connected
callout has returned, as well as, prevent the disconnected callout to
occur before the disconnecting callout has returned.

Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:35:03 -08:00
Dean Roe
c2a4969ba1 [IA64-SGI] fix the size of __sn_cnodeid_to_nasid
The __sn_cnodeid_to_nasid array was incorrectly sized at MAX_NUMNODES.
On a large system, this array could overflow.  The following patch
corrects this by defining it to MAX_COMPACT_NODES.

Signed-off-by: Dean Roe <roe@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:33:48 -08:00
Mark Maule
9c65cb9be6 [IA64-SGI] export sn_pcidev_info_get
Export sn_pcidev_info_get.

Signed-off-by Mark Maule <maule@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:28:48 -08:00
Jes Sorensen
26d10915de [IA64-SGI] remove compile time warning
This one falls into the "present for Andrew Morton" category to address
his wishlist for a compiler warning free build ;-)

Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:27:02 -08:00
Jes Sorensen
d3454344b3 [IA64] remove obsolete corporate address
Remove obsolete SGI address

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:25:37 -08:00
Jes Sorensen
8ed9b2c7a8 [IA64-SGI] sn2 minor fixes and cleanups
General SN2 code cleanup:
 - Do not initialize global variables to zero
 - Use kzalloc instead of kmalloc+memset
 - Check kmalloc return values
 - Do not obfuscate spin lock calls
 - Remove some unused code
 - Various formatting cleanups

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:24:45 -08:00
Andreas Schwab
50d8e59038 [IA64] Remove duplicate EXPORT_SYMBOLs
Remove symbol exports from ia64_ksyms.c that are already exported in
lib/string.c.

Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-15 13:23:32 -08:00
Herbert Poetzl
ba09cf2bcf [ARM] remove duplicate #includes
Signed-off-by: Herbert P?tzl <herbert@13thfloor.at>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-15 10:13:02 +00:00
Thomas Meyer
e2fbf1ace5 [PATCH] x86: gitignore some autogenerated files for i386
Add some more gitignore files for i386 architecture.  This files are
created during the build process of a i386 kernel.

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
Albert D. Cahalan
581141cb4b [PATCH] x86: document sysenter path
This path isn't obvious.  It looks as if the kernel will be taking three
args from the user stack, but it only takes one from there.

Signed-off-by: Albert Cahalan <acahalan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
David Howells
28baebae73 [PATCH] FRV: Use virtual interrupt disablement
Make the FRV arch use virtual interrupt disablement because accesses to the
processor status register (PSR) are relatively slow and because we will
soon have the need to deal with multiple interrupt controls at the same
time (separate h/w and inter-core interrupts).

The way this is done is to dedicate one of the four integer condition code
registers (ICC2) to maintaining a virtual interrupt disablement state
whilst inside the kernel.  This uses the ICC2.Z flag (Zero) to indicate
whether the interrupts are virtually disabled and the ICC2.C flag (Carry)
to indicate whether the interrupts are physically disabled.

ICC2.Z is set to indicate interrupts are virtually disabled.  ICC2.C is set
to indicate interrupts are physically enabled.  Under normal running
conditions Z==0 and C==1.

Disabling interrupts with local_irq_disable() doesn't then actually
physically disable interrupts - it merely sets ICC2.Z to 1.  Should an
interrupt then happen, the exception prologue will note ICC2.Z is set and
branch out of line using one instruction (an unlikely BEQ).  Here it will
physically disable interrupts and clear ICC2.C.

When it comes time to enable interrupts (local_irq_enable()), this simply
clears the ICC2.Z flag and invokes a trap #2 if both Z and C flags are
clear (the HI integer condition).  This can be done with the TIHI
conditional trap instruction.

The trap then physically reenables interrupts and sets ICC2.C again.  Upon
returning the interrupt will be taken as interrupts will then be enabled.
Note that whilst processing the trap, the whole exceptions system is
disabled, and so an interrupt can't happen till it returns.

If no pending interrupt had happened, ICC2.C would still be set, the HI
condition would not be fulfilled, and no trap will happen.

Saving interrupts (local_irq_save) is simply a matter of pulling the ICC2.Z
flag out of the CCR register, shifting it down and masking it off.  This
gives a result of 0 if interrupts were enabled and 1 if they weren't.

Restoring interrupts (local_irq_restore) is then a matter of taking the
saved value mentioned previously and XOR'ing it against 1.  If it was one,
the result will be zero, and if it was zero the result will be non-zero.
This result is then used to affect the ICC2.Z flag directly (it is a
condition code flag after all).  An XOR instruction does not affect the
Carry flag, and so that bit of state is unchanged.  The two flags can then
be sampled to see if they're both zero using the trap (TIHI) as for the
unconditional reenablement (local_irq_enable).

This patch also:

 (1) Modifies the debugging stub (break.S) to handle single-stepping crossing
     into the trap #2 handler and into virtually disabled interrupts.

 (2) Removes superseded fixup pointers from the second instructions in the trap
     tables (there's no a separate fixup table for this).

 (3) Declares the trap #3 vector for use in .org directives in the trap table.

 (4) Moves irq_enter() and irq_exit() in do_IRQ() to avoid problems with
     virtual interrupt handling, and removes the duplicate code that has now
     been folded into irq_exit() (softirq and preemption handling).

 (5) Tells the compiler in the arch Makefile that ICC2 is now reserved.

 (6) Documents the in-kernel ABI, including the virtual interrupts.

 (7) Renames the old irq management functions to different names.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
David Howells
68f624fc8b [PATCH] FRV: Miscellaneous fixes
Make various alterations and fixes to the FRV arch:

 (1) Resyncs the FRV system call collection with the i386 arch.

 (2) Discards __iounmap() as it's not used.

 (3) Fixes the use of the SWAP/SWAPI instruction to get the arguments the right
     way around in atomic.h, and also to get the asm constraints correct.

 (4) Moves copy_to/from_user_page() to asm/cacheflush.h to be consistent with
     other archs.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
Ingo Molnar
06027bdd27 [PATCH] hrtimer: round up relative start time on low-res arches
CONFIG_TIME_LOW_RES is a temporary way for architectures to signal that
they simply return xtime in do_gettimeoffset().  In this corner-case we
want to round up by resolution when starting a relative timer, to avoid
short timeouts.  This will go away with the GTOD framework.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
Heiko Carstens
e35a6619e7 [PATCH] s390: fix __delay implementation
Fix __delay implementation.  Called with an argument "1" or "0" it would
loop nearly forever (since (1/2)-1 = 0xffffffff).

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
Adrian Bunk
5a1342f773 [PATCH] fix a typo in the CPU_H8300H dependencies
Jean-Luc Leger <reiga@dspnet.fr.eu.org> found this obvious typo.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:35 -08:00
Ashok Raj
a6b14fa6fd [IA64] Count disabled cpus as potential hot-pluggable CPUs
Have a facility to account for potentially hot-pluggable CPUs. ACPI doesnt
give a determinstic method to find hot-pluggable CPUs. Hence we use 2 methods
to assist.

- BIOS can mark potentially hot-pluggable CPUs as disabled in the MADT tables.
- User can specify the number of hot-pluggable CPUs via parameter
  additional_cpus=X

The option is enabled only if ACPI_CONFIG_HOTPLUG_CPU=y which enables the
physical hotplug option. Without which user can still use logical onlining
and offlining of CPUs by enabling CONFIG_HOTPLUG_CPU=y

Adds more bits to cpu_possible_map for potentially hot-pluggable cpus.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-14 15:37:58 -08:00