Commit Graph

47 Commits

Author SHA1 Message Date
Alex Chiang
c0acdea214 [IA64] Remove redundant cpu_clear() in __cpu_disable path
The second call to cpu_clear() is redundant, as we've already removed
the CPU from cpu_online_map before calling migrate_platform_irqs().

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
2009-02-19 11:32:50 -08:00
Alex Chiang
66db2e6331 [IA64] Revert "prevent ia64 from invoking irq handlers on offline CPUs"
This reverts commit e7b140365b.

Commit e7b14036 removes the targetted disabled CPU from the
cpu_online_map after calls to migrate_platform_irqs and fixup_irqs.

Paul McKenney states that the reasoning behind the patch was to
prevent irq handlers from running on CPUs marked offline because:

	RCU happily ignores CPUs that don't have their bits set in
	cpu_online_map, so if there are RCU read-side critical sections
	in the irq handlers being run, RCU will ignore them.  If the
	other CPUs were running, they might sequence through the RCU
	state machine, which could result in data structures being
	yanked out from under those irq handlers, which in turn could
	result in oopses or worse.

Unfortunately, both ia64 functions above look at cpu_online_map to find
a new CPU to migrate interrupts onto. This means we can potentially
migrate an interrupt off ourself back to... ourself. Uh oh.

This causes an oops when we finally try to process pending interrupts on
the CPU we want to disable. The oops results from calling __do_IRQ with
a NULL pt_regs:

Unable to handle kernel NULL pointer dereference (address 0000000000000040)
Call Trace:
 [<a000000100016930>] show_stack+0x50/0xa0
                                sp=e0000009c922fa00 bsp=e0000009c92214d0
 [<a0000001000171a0>] show_regs+0x820/0x860
                                sp=e0000009c922fbd0 bsp=e0000009c9221478
 [<a00000010003c700>] die+0x1a0/0x2e0
                                sp=e0000009c922fbd0 bsp=e0000009c9221438
 [<a0000001006e92f0>] ia64_do_page_fault+0x950/0xa80
                                sp=e0000009c922fbd0 bsp=e0000009c92213d8
 [<a00000010000c7a0>] ia64_native_leave_kernel+0x0/0x270
                                sp=e0000009c922fc60 bsp=e0000009c92213d8
 [<a0000001000ecdb0>] profile_tick+0xd0/0x1c0
                                sp=e0000009c922fe30 bsp=e0000009c9221398
 [<a00000010003bb90>] timer_interrupt+0x170/0x3e0
                                sp=e0000009c922fe30 bsp=e0000009c9221330
 [<a00000010013a800>] handle_IRQ_event+0x80/0x120
                                sp=e0000009c922fe30 bsp=e0000009c92212f8
 [<a00000010013aa00>] __do_IRQ+0x160/0x4a0
                                sp=e0000009c922fe30 bsp=e0000009c9221290
 [<a000000100012290>] ia64_process_pending_intr+0x2b0/0x360
                                sp=e0000009c922fe30 bsp=e0000009c9221208
 [<a0000001000112d0>] fixup_irqs+0xf0/0x2a0
                                sp=e0000009c922fe30 bsp=e0000009c92211a8
 [<a00000010005bd80>] __cpu_disable+0x140/0x240
                                sp=e0000009c922fe30 bsp=e0000009c9221168
 [<a0000001006c5870>] take_cpu_down+0x50/0xa0
                                sp=e0000009c922fe30 bsp=e0000009c9221148
 [<a000000100122610>] stop_cpu+0xd0/0x200
                                sp=e0000009c922fe30 bsp=e0000009c92210f0
 [<a0000001000e0440>] kthread+0xc0/0x140
                                sp=e0000009c922fe30 bsp=e0000009c92210c8
 [<a000000100014ab0>] kernel_thread_helper+0xd0/0x100
                                sp=e0000009c922fe30 bsp=e0000009c92210a0
 [<a00000010000a4c0>] start_kernel_thread+0x20/0x40
                                sp=e0000009c922fe30 bsp=e0000009c92210a0

I don't like this revert because it is fragile. ia64 is getting lucky
because we seem to only ever process timer interrupts in this path, but
if we ever race with an IPI here, we definitely use RCU and have the
potential of hitting an oops that Paul describes above.

Patching ia64's timer_interrupt() to check for NULL pt_regs is
insufficient though, as we still hit the above oops.

As a short term solution, I do think that this revert is the right
answer. The revert hold up under repeated testing (24+ hour test runs)
with this setup:

	- 8-way rx6600
	- randomly toggling CPU online/offline state every 2 seconds
	- running CPU exercisers, memory hog, disk exercisers, and
	  network stressors
	- average system load around ~160

In the long term, we really need to figure out why we set pt_regs = NULL
in ia64_process_pending_intr(). If it turns out that it is unnecessary
to do so, then we could safely re-introduce e7b14036 (along with some
other logic to be smarter about migrating interrupts).

One final note: x86 also removes the disabled CPU from cpu_online_map
and then re-enables interrupts for 1ms, presumably to handle any pending
interrupts:

arch/x86/kernel/irq_32.c (and irq_64.c):
cpu_disable_common:
	[remove cpu from cpu_online_map]

	fixup_irqs():
		for_each_irq:
			[break CPU affinities]

		local_irq_enable();
		mdelay(1);
		local_irq_disable();

So they are doing implicitly what ia64 is doing explicitly.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
2009-02-19 11:32:26 -08:00
Rusty Russell
0de26520c7 cpumask: make irq_set_affinity() take a const struct cpumask
Impact: change existing irq_chip API

Not much point with gentle transition here: the struct irq_chip's
setaffinity method signature needs to change.

Fortunately, not widely used code, but hits a few architectures.

Note: In irq_select_affinity() I save a temporary in by mangling
irq_desc[irq].affinity directly.  Ingo, does this break anything?

(Folded in fix from KOSAKI Motohiro)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: jeremy@xensource.com
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
2008-12-13 21:20:26 +10:30
Rusty Russell
98a79d6a50 cpumask: centralize cpu_online_map and cpu_possible_map
Impact: cleanup

Each SMP arch defines these themselves.  Move them to a central
location.

Twists:
1) Some archs (m32, parisc, s390) set possible_map to all 1, so we add a
   CONFIG_INIT_ALL_POSSIBLE for this rather than break them.

2) mips and sparc32 '#define cpu_possible_map phys_cpu_present_map'.
   Those archs simply have phys_cpu_present_map replaced everywhere.

3) Alpha defined cpu_possible_map to cpu_present_map; this is tricky
   so I just manipulate them both in sync.

4) IA64, cris and m32r have gratuitous 'extern cpumask_t cpu_possible_map'
   declarations.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Mike Travis <travis@sgi.com>
Cc: ink@jurassic.park.msu.ru
Cc: rmk@arm.linux.org.uk
Cc: starvik@axis.com
Cc: tony.luck@intel.com
Cc: takata@linux-m32r.org
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: paulus@samba.org
Cc: schwidefsky@de.ibm.com
Cc: lethal@linux-sh.org
Cc: wli@holomorphy.com
Cc: davem@davemloft.net
Cc: jdike@addtoit.com
Cc: mingo@redhat.com
2008-12-13 21:19:41 +10:30
Ingo Molnar
990d0f2ced Merge branches 'sched/devel', 'sched/cpu-hotplug', 'sched/cpusets' and 'sched/urgent' into sched/core 2008-10-08 11:31:02 +02:00
Paul E. McKenney
e7b140365b [IA64] prevent ia64 from invoking irq handlers on offline CPUs
Make ia64 refrain from clearing a given to-be-offlined CPU's bit in the
cpu_online_mask until it has processed pending irqs.  This change
prevents other CPUs from being blindsided by an apparently offline CPU
nevertheless changing globally visible state.  Also remove the existing
redundant cpu_clear(cpu, cpu_online_map).

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-09-10 10:52:42 -07:00
Manfred Spraul
e545a6140b kernel/cpu.c: create a CPU_STARTING cpu_chain notifier
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>
2008-09-08 19:25:24 +02:00
Robin Holt
42aca483dd [IA64] Fix ia64 build failure when CONFIG_SFC=m
CONFIG_SFC=m uses topology_core_siblings() which, for ia64, expects
cpu_core_map to be exported.  It is not.  This patch exports the needed
symbol.

Maintainers note: This really looks like the wrong thing to do ... it
would be much better for the kernel to export an API to provide
drivers like this with data they need (which in the case of this
driver seems to be an estimate of the effective parallelism available
on the platform).  But x86 has exported this forever ... so go with
the flow until such an API is defined.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-08-25 11:10:11 -07:00
Tony Luck
10617bbe84 [IA64] Ensure cpu0 can access per-cpu variables in early boot code
ia64 handles per-cpu variables a litle differently from other architectures
in that it maps the physical memory allocated for each cpu at a constant
virtual address (0xffffffffffff0000). This mapping is not enabled until
the architecture specific cpu_init() function is run, which causes problems
since some generic code is run before this point. In particular when
CONFIG_PRINTK_TIME is enabled, the boot cpu will trap on the access to
per-cpu memory at the first printk() call so the boot will fail without
the kernel printing anything to the console.

Fix this by allocating percpu memory for cpu0 in the kernel data section
and doing all initialization to enable percpu access in head.S before
calling any generic code.

Other cpus must take care not to access per-cpu variables too early, but
their code path from start_secondary() to cpu_init() is all in arch/ia64

Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-08-12 10:34:20 -07:00
Tony Luck
fca515fbfa Pull pvops into release branch 2008-07-17 10:53:37 -07:00
Jens Axboe
8691e5a8f6 smp_call_function: get rid of the unused nonatomic/retry argument
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>
2008-06-26 11:24:35 +02:00
Jens Axboe
f27b433ef3 ia64: convert to generic helpers for IPI function calls
This converts ia64 to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().

Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:22:30 +02:00
Isaku Yamahata
e51835d58a [IA64] pvops: define initialization hooks, pv_init_ops, for paravirtualized environment.
define pv_init_ops hooks which represents various initialization
hooks for paravirtualized environment. and add hooks.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-05-27 15:10:06 -07:00
Alex Chiang
6ff0bc94ee [IA64] Remove printk noise on unimplemented SAL_PHYSICAL_ID_INFO
Commit 113134fcbc changed the flow of
control when calling PAL_LOGICAL_TO_PHYSICAL and SAL_PHYSICAL_ID_INFO.
With the change, if a platform did not implement the latter, a useless
printk would appear in the boot log:

	ia64_sal_pltid failed with -1

So let's check the return code and only printk on a true error, and do
not print anything in the unimplemented case. While we're in there,
clean up some stylistic issues too.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-04-29 13:51:28 -07:00
Alan D. Brunelle
e914501611 [IA64] Fix unlock ordering in smp_callin
One should normally unlock in the reverse order of the lock calls,
and in this case there certainly is no reason not to.

Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-04-09 10:13:13 -07:00
Adrian Bunk
6b2fb3c658 idle_regs() must be __cpuinit
Fix the following section mismatch with CONFIG_HOTPLUG=n,
CONFIG_HOTPLUG_CPU=y:

WARNING: vmlinux.o(.text+0x399a6): Section mismatch: reference to .init.text.5:idle_regs (between 'fork_idle' and 'get_task_mm')

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:08 -08:00
Adrian Bunk
6c81c32f96 calibrate_delay() must be __cpuinit
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>
2008-02-06 10:41:08 -08:00
Jan Beulich
ef3c4cb936 [IA64] remove dead code: __cpu_{down,die} from !HOTPLUG_CPU
Neither __cpu_down() nor __cpu_die() are being referenced without
CONFIG_HOTPLUG_CPU.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-02-05 08:26:08 -08:00
Alex Chiang
113134fcbc [IA64] /proc/cpuinfo "physical id" field cleanups
Clean up the process for presenting the "physical id" field in
/proc/cpuinfo.

	- remove global smp_num_cpucores, as it is mostly useless

	- remove check_for_logical_procs(), since we do the same
	  functionality in identify_siblings()

	- reflow logic in identify_siblings(). If an older CPU
	  does not implement PAL_LOGICAL_TO_PHYSICAL, we may still
	  be able to get useful information from SAL_PHYSICAL_ID_INFO

	- in identify_siblings(), threads/cores are a property of
	  the CPU, not the platform

	- remove useless printk's about multi-core / thread
	  capability in identify_siblings(), as that information
	  is readily available in /proc/cpuinfo, and printing for
	  the BSP only adds little value

	- smp_num_siblings is now meaningful if any CPU in the
	  system supports threads, not just the BSP

	- expose "physical id" field, even on CPUs that are not
	  multi-core / multi-threaded (as long as we have a valid
	  value). Now we know what sockets Madisons live in too.

Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-10-29 11:14:54 -07:00
Mike Travis
d5a7430ddc Convert cpu_sibling_map to be a per cpu variable
Convert cpu_sibling_map from a static array sized by NR_CPUS to a per_cpu
variable.  This saves sizeof(cpumask_t) * NR unused cpus.  Access is mostly
from startup and CPU HOTPLUG functions.

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:50 -07:00
John Keller
6e9de18120 [IA64] SN: Add support for CPU disable
Add additional support for CPU disable on SN platforms.
Correctly setup the smp_affinity mask for I/O error IRQs.
Restrict the use of the feature to Altix 4000 and 450 systems
running with a CPU disable capable PROM, and do not allow disabling
of CPU 0.

Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-09-01 02:49:57 -07:00
Tony Luck
9d6f40b86b [IA64] fix section mismatch warnings
In 741f98fe29 Sam added full
checking across the entire vmlinux image.  This flushed out
a dozen new section mismatch warnings.  Start the whack-a-mole
game again to stomp them out.

Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-07-25 13:08:26 -07:00
Yasuaki Ishimatsu
e1b30a3928 [IA64] Add mapping table between irq and vector
Add mapping tables between irqs and vectors, and its management code.
This is necessary for supporting multiple vector domain because 1:1
mapping between irq and vector will be changed to n:1.

The irq == vector relationship between irqs and vectors is explicitly
remained for percpu interrupts, platform interrupts, isa IRQs and
vectors assigned using assign_irq_vector() because some programs might
depend on it.

And I should consider the following problem.

When pci drivers enabled/disabled devices dynamically, its irq number
is changed to the different one. Therefore, suspend/resume code may
happen problem.

To fix this problem, I bound gsi to irq.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-07-17 09:51:49 -07:00
Tony Luck
d86ebd1409 [IA64] start_secondary() and smp_callin() should be __cpuinit
Continuing the seemingly neverending quest to stomp out "Section
mismatch" warnings.

Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-05-23 16:46:40 -07:00
Simon Arlott
72fdbdce3d [IA64] spelling fixes: arch/ia64/
Spelling and apostrophe fixes in arch/ia64/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-05-11 14:55:43 -07:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
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>
2007-05-08 11:15:07 -07:00
Jack Steiner
ead6caae1e [IA64] Speed up boot - skip unnecessary clock calibration
Skip clock calibration if cpu being brought online is exactly the same
speed, stepping, etc., as the previous cpu. This significantly reduces
the time to boot very large systems.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-29 15:17:11 -07:00
David Howells
6d5aefb8ea WorkQueue: Fix up arch-specific work items where possible
Fix up arch-specific work items where possible to use the new work_struct and
delayed_work structs.

Three places that enqueue bits of their stack and then return have been marked
with #error as this is not permitted.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 19:36:26 +00:00
Stephane Eranian
dd562c0541 [IA64] Add interface so modules can discover whether multithreading is on.
Add is_multithreading_enabled() to check whether multi-threading
is enabled independently of which cpu is currently online

Signed-off-by: stephane eranian <eranian@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-09-26 11:39:38 -07:00
Ingo Molnar
36c8b58689 [PATCH] sched: cleanup, remove task_t, convert to struct task_struct
cleanup: remove task_t and convert all the uses to struct task_struct. I
introduced it for the scheduler anno and it was a mistake.

Conversion was mostly scripted, the result was reviewed and all
secondary whitespace and style impact (if any) was fixed up by hand.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:11 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Ingo Molnar
a8553acd6c [PATCH] genirq: cleanup: remove irq_descp()
Cleanup: remove irq_descp() - explicit use of irq_desc[] is shorter and more
readable.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar
d1bef4ed5f [PATCH] genirq: rename desc->handler to desc->chip
This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.

While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.

The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.

This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.

As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.

The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.

We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.

This patch:

rename desc->handler to desc->chip.

Originally i did not want to do this, because it's a big patch.  But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.

I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.

So lets get over with this quickly.  The conversion was done automatically
via scripts and converts all the code in the kernel.

This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.

[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:21 -07:00
Fenghua Yu
4129a953ad [IA64] New IA64 core/thread detection patch
IPF SDM 2.2 changes definition of PAL_LOGICAL_TO_PHYSICAL to add
proc_number=-1 to get core/thread mapping info on the running processer.

Based on this change, we had better to update existing core/thread
detection in IA64 kernel correspondingly. The attached patch implements
this change. It simplifies detection code and eliminates potential race
condition. It also runs a bit faster and has better scalability especially
when cores and threads number grows up in one package.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-24 13:15:23 -08:00
Tony Luck
536ea4e419 Pull bsp-removal into release branch 2006-03-21 08:16:21 -08:00
Ashok Raj
69aa234b91 [IA64] Dont set NR_CPUS for cpu_possible_map when CPU hotplug is enabled.
Do not set cpu_possible_map for NR_CPUS when ACPI_CONFIG_HOTPLUG_CPU is set.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-14 15:35:10 -08:00
Ashok Raj
ff741906ad [IA64] support for cpu0 removal
here is the BSP removal support for IA64. Its pretty much the same thing that
was released a while back, but has your feedback incorporated.

- Removed CONFIG_BSP_REMOVE_WORKAROUND and associated cmdline param
- Fixed compile issue with sn2/zx1 due to a undefined fix_b0_for_bsp
- some formatting nits (whitespace etc)

This has been tested on tiger and long back by alex on hp systems as well.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-01-05 10:24:20 -08:00
Nick Piggin
5bfb5d690f [PATCH] sched: disable preempt in idle tasks
Run idle threads with preempt disabled.

Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?

Might fix the CPU hotplugging hang which Nigel Cunningham noted.

We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.

After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep.  The CPU will continue executing
previous idle and have no chance to call play_dead.

By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.

From: alexs <ashepard@u.washington.edu>

  PPC build fix

From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>

  MIPS build fix

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00
hawkes@sgi.com
dc565b525d [IA64] wider use of for_each_cpu_mask() in arch/ia64
In arch/ia64 change the explicit use of for-loops and NR_CPUS into the
general for_each_cpu() or for_each_online_cpu() constructs, as
appropriate.  This widens the scope of potential future optimizations
of the general constructs, as well as takes advantage of the existing
optimizations of first_cpu() and next_cpu().

Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-10-25 15:10:08 -07:00
Tony Luck
8d7e35174d [IA64] fix generic/up builds
Jesse Barnes provided the original version of this patch months ago, but
other changes kept conflicting with it, so it got deferred.  Greg Edwards
dug it out of obscurity just over a week ago, and almost immediately
another conflicting patch appeared (Bob Picco's memory-less nodes).

I've resolved the conflicts and got it running again.  CONFIG_SGI_TIOCX
is set to "y" in defconfig, which causes a Tiger to not boot (oops in
tiocx_init).  But that can be resolved later ... get this in now before it
gets stale again.

Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-07-06 18:18:10 -07:00
Shaohua Li
a9fa06c26f [PATCH] set cpu_state for CPU hotplug (ia64)
Dead CPU notifies online CPU that it's dead using cpu_state variable.
After switching to physical cpu hotplug, we forgot setting the variable.
This patch fixes it.  Currently only __cpu_die uses it.  We changed other
locations for consistency in case others use it.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Ashok Raj <ashok.raj@intel.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:31 -07:00
Zwane Mwaikambo
f370513640 [PATCH] i386 CPU hotplug
(The i386 CPU hotplug patch provides infrastructure for some work which Pavel
is doing as well as for ACPI S3 (suspend-to-RAM) work which Li Shaohua
<shaohua.li@intel.com> is doing)

The following provides i386 architecture support for safely unregistering and
registering processors during runtime, updated for the current -mm tree.  In
order to avoid dumping cpu hotplug code into kernel/irq/* i dropped the
cpu_online check in do_IRQ() by modifying fixup_irqs().  The difference being
that on cpu offline, fixup_irqs() is called before we clear the cpu from
cpu_online_map and a long delay in order to ensure that we never have any
queued external interrupts on the APICs.  There are additional changes to s390
and ppc64 to account for this change.

1) Add CONFIG_HOTPLUG_CPU
2) disable local APIC timer on dead cpus.
3) Disable preempt around irq balancing to prevent CPUs going down.
4) Print irq stats for all possible cpus.
5) Debugging check for interrupts on offline cpus.
6) Hacky fixup_irqs() to redirect irqs when cpus go off/online.
7) play_dead() for offline cpus to spin inside.
8) Handle offline cpus set in flush_tlb_others().
9) Grab lock earlier in smp_call_function() to prevent CPUs going down.
10) Implement __cpu_disable() and __cpu_die().
11) Enable local interrupts in cpu_enable() after fixup_irqs()
12) Don't fiddle with NMI on dead cpu, but leave intact on other cpus.
13) Program IRQ affinity whilst cpu is still in cpu_online_map on offline.

Signed-off-by: Zwane Mwaikambo <zwane@linuxpower.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:29 -07:00
David Mosberger-Tang
66302f211a [IA64] fix "section mismatch" compile-time-error
I noticed this typo when trying to compile a kernel which had
CONFIG_HOTPLUG turned off.  In that case, __devinit is no longer a
no-op and the compiler then detects a section-conflict.  Fix by using
__devinitdata instead of __devinit.

Same patch also submitted by Darren Williams to fix compilation error
using sim_defconfig (which has CONFIG_HOTPLUG=n).

Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by:  Darren Williams <dsw@gelato.unsw.edu.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-05-09 10:16:17 -07:00
Suresh Siddha
e927ecb05e [IA64] multi-core/multi-thread identification
Version 3 - rediffed to apply on top of Ashok's hotplug cpu
patch.  /proc/cpuinfo output in step with x86.

This is an updated MC/MT identification patch based on the 
previous discussions on list. 

Add the Multi-core and Multi-threading detection for IPF.
  - Add new core and threading related fields in /proc/cpuinfo.
		Physical id
		Core id
		Thread id
		Siblings
  - setup the cpu_core_map and cpu_sibling_map appropriately
  - Handles Hot plug CPU
 
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Gordon Jin <gordon.jin@intel.com>
Signed-off-by: Rohit Seth <rohit.seth@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-04-25 13:25:06 -07:00
David Mosberger-Tang
8297511530 [IA64] add missing cpu_relax() in ITC syncing code
Call cpu_relax() in busy-waiting loops of the ITC-syncing code.

Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-04-25 11:44:02 -07:00
Ashok Raj
b8d8b883e6 [IA64] cpu hotplug: return offlined cpus to SAL
This patch is required to support cpu removal for IPF systems. Existing code
just fakes the real offline by keeping it run the idle thread, and polling
for the bit to re-appear in the cpu_state to get out of the idle loop.

For the cpu-offline to work correctly, we need to pass control of this CPU 
back to SAL so it can continue in the boot-rendez mode. This gives the
SAL control to not pick this cpu as the monarch processor for global MCA
events, and addition does not wait for this cpu to checkin with SAL
for global MCA events as well. The handoff is implemented as documented in 
SAL specification section 3.2.5.1 "OS_BOOT_RENDEZ to SAL return State"

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-04-22 14:44:40 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00