For some reason we had two parsers registered for maxcpus=. One in init/main.c
and another in arch/x86/smpboot.c. So I nuked the one in arch/x86.
Also 64-bit kernels used to handle maxcpus= as documented in
Documentation/cpu-hotplug.txt. CPUs with 'id > maxcpus' are initialized
but not booted. 32-bit version for some reason ignored them even though
all the infrastructure for booting them later is there.
In the current mainline both 64 and 32 bit versions are broken.
This patch restores the correct behaviour. I've tested x86_64 version on
4- and 8- way Core2 and 2-way Opteron based machines. Various config
combinations SMP, !SMP, CPU_HOTPLUG, !CPU_HOTPLUG.
Booted with maxcpus=1 and maxcpus=4, etc. Everything is working as expected.
So far we've received two reports from different people confirming that 32-bit
version also works fine, both on dual core laptops and 16way server machines.
[v2: This version fixes visws breakage pointed out by Ingo.]
Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Cc: lizf@cn.fujitsu.com
Cc: jeff.chua.linux@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
... so don't need to call clear_cpu_cap again in early_identify_cpu,
and could use cleared_cpu_caps like other places.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
As a microoptimisation, make apic_verbosity unsigned. This will make
apic_printk(APIC_QUIET, ...) expand into just printk(...) with the
surrounding condition and a reference to apic_verbosity removed.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There is no need to keep NMI_DISABLED definition and use it
for nmi_watchdog by default. Here is the point why:
- IO-APIC and APIC chips are programmed for nmi_watchdog support at very
early stage of kernel booting and not having nmi_watchdog specified as
boot option lead only to nmi_watchdog becomes to NMI_NONE anyway
- enable nmi_watchdog thru /proc/sys/kernel/nmi if it was not specified at
boot is not possible too (even having this sysfs entry)
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Since it is possible NMI_ definitions could be changed
one day we better print out real nmi_watchdog value instead
of constant string.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Although it is not really needed, we provide it to get
closer to i386. ifdefs around it are removed in smpboot.c
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
physid_mask_of_physid() causes a huge stack (12k) to be created if the
number of APICS is large. Replace physid_mask_of_physid() with a
new function that does not create large stacks. This is a problem only
on large x86_64 systems.
this paves the way to increase MAX_APICS.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
Cc: mingo@elte.hu
Cc: tglx@linutronix.de
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Introduce a new PER_CPU macro called "EARLY_PER_CPU". This is
used by some per_cpu variables that are initialized and accessed
before there are per_cpu areas allocated.
["Early" in respect to per_cpu variables is "earlier than the per_cpu
areas have been setup".]
This patchset adds these new macros:
DEFINE_EARLY_PER_CPU(_type, _name, _initvalue)
EXPORT_EARLY_PER_CPU_SYMBOL(_name)
DECLARE_EARLY_PER_CPU(_type, _name)
early_per_cpu_ptr(_name)
early_per_cpu_map(_name, _idx)
early_per_cpu(_name, _cpu)
The DEFINE macro defines the per_cpu variable as well as the early
map and pointer. It also initializes the per_cpu variable and map
elements to "_initvalue". The early_* macros provide access to
the initial map (usually setup during system init) and the early
pointer. This pointer is initialized to point to the early map
but is then NULL'ed when the actual per_cpu areas are setup. After
that the per_cpu variable is the correct access to the variable.
The early_per_cpu() macro is not very efficient but does show how to
access the variable if you have a function that can be called both
"early" and "late". It tests the early ptr to be NULL, and if not
then it's still valid. Otherwise, the per_cpu variable is used
instead:
#define early_per_cpu(_name, _cpu) \
(early_per_cpu_ptr(_name) ? \
early_per_cpu_ptr(_name)[_cpu] : \
per_cpu(_name, _cpu))
A better method is to actually check the pointer manually. In the
case below, numa_set_node can be called both "early" and "late":
void __cpuinit numa_set_node(int cpu, int node)
{
int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
if (cpu_to_node_map)
cpu_to_node_map[cpu] = node;
else
per_cpu(x86_cpu_to_node_map, cpu) = node;
}
* Add a flag "arch_provides_topology_pointers" that indicates pointers
to topology cpumask_t maps are available. Otherwise, use the function
returning the cpumask_t value. This is useful if cpumask_t set size
is very large to avoid copying data on to/off of the stack.
* The coverage of CONFIG_DEBUG_PER_CPU_MAPS has been increased while
the non-debug case has been optimized a bit.
* Remove an unreferenced compiler warning in drivers/base/topology.c
* Clean up #ifdef in setup.c
For inclusion into sched-devel/latest tree.
Based on:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
+ sched-devel/latest .../mingo/linux-2.6-sched-devel.git
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If configured to use the I/O APIC, the NMI watchdog is deemed to fail if
the chip will not be used in the UP configuration, because "noapic" has
been specified or the chip is simply not there. Downgrade to the local
APIC watchdog to rectify.
The new #ifdef is ugly, I know. A proper solution is to provide suitable
definitions of smp_found_config, etc. for !CONFIG_X86_IO_APIC in a header.
Likewise the whole if () condition should be moved to a static inline
function. Such clean-ups are beyond the scope of this change and can be
done once the whole issue of the timer has been sorted out.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
nmi_watchdog=1 hangs on 64-bit:
[ 0.250000] Detected 12.564 MHz APIC timer.
[ 0.254178] APIC timer registered as dummy, due to nmi_watchdog=1!
[ 0.260366] Testing NMI watchdog ... <4>WARNING: CPU#0: NMI appears to be stuck (0->0)!
[ ... ]
[ 0.470003] calling genl_init+0x0/0xd0
[ hard hang ]
bisected it down to:
git-bisect start
git-bisect good 1beee8dc8c
git-bisect bad 11582ece0aaa2d0f94f345c08a4ab9997078a083
git-bisect bad 5479c623bb44089844022c03d4c0eb16d5b7a15f
git-bisect bad cfb4c7fabeb499e1c29f9d1878968e37a938e28a
git-bisect good 246dd412d3
git-bisect bad 3f8237eaff7dc1e35fa791dae095574fd974e671
git-bisect good 90e23b13ab849e2a11f00c655eb3a2011b4623be
git-bisect bad 833526a34eeefc117df3191a594c3c3a4f15a9ac
git-bisect good 791b93d3dfaf16c23e978bec0cc0a3dd9d855d63
git-bisect bad 65767c64068f2c93e56a1accfed5c78230ac12d7
git-bisect bad 2abc5c05dd82c188e3bdf6641a274f013348d14b
git-bisect bad 317e1f2597ffb4d4db940577bbe56dc6e881ef07
| 317e1f2597ffb4d4db940577bbe56dc6e881ef07 is first bad commit
| commit 317e1f2597ffb4d4db940577bbe56dc6e881ef07
| Author: Maciej W. Rozycki <macro@linux-mips.org>
| Date: Wed May 21 22:10:22 2008 +0100
| x86: I/O APIC: clean up the 8259A on a NMI watchdog failure
the problem is that in the dummy-lapic branch we rely on the i8259A
but if the NMI watchdog fails we turn off IRQ 0 - which doesnt work
too well ;-)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
C1E on AMD machines is like C3 but without control from the OS. Up to
now we disabled the local apic timer for those machines as it stops
when the CPU goes into C1E. This excludes those machines from high
resolution timers / dynamic ticks, which hurts especially X2 based
laptops.
The current boot time C1E detection has another, more serious flaw
as well: some BIOSes do not enable C1E until the ACPI processor module
is loaded. This causes systems to stop working after that point.
To work nicely with C1E enabled machines we use a separate idle
function, which checks on idle entry whether C1E was enabled in the
Interrupt Pending Message MSR. This allows us to do timer broadcasting
for C1E and covers the late enablement of C1E as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
a multi-socket test-system with 3 or 4 ioapics, when 4 dualcore cpus or
2 quadcore cpus installed, needs to switch to bigsmp or physflat.
CPU apic id is [4,11] instead of [0,7], and we need to check max apic
id instead of cpu numbers.
also add check for 32 bit when acpi is not compiled in or acpi=off.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
A check for unmapped apic was added before reading maxlvt but the early
read of maxlvt wasn't removed.
Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
Remove the magic number in the third argment of div_sc().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
UV supports really big systems. So big, in fact, that the APICID register
does not contain enough bits to contain an APICID that is unique across all
cpus.
The UV BIOS supports 3 APICID modes:
- legacy mode. This mode uses the old APIC mode where
APICID is in bits [31:24] of the APICID register.
- x2apic mode. This mode is whitebox-compatible. APICIDs
are unique across all cpus. Standard x2apic APIC operations
(Intel-defined) can be used for IPIs. The node identifier
fits within the Intel-defined portion of the APICID register.
- x2apic-uv mode. In this mode, the APICIDs on each node have
unique IDs, but IDs on different node are not unique. For example,
if each mode has 32 cpus, the APICIDs on each node might be
0 - 31. Every node has the same set of IDs.
The UV hub is used to route IPIs/interrupts to the correct node.
Traditional APIC operations WILL NOT WORK.
In x2apic-uv mode, the ACPI tables all contain a full unique ID (note:
exact bit layout still changing but the following is close):
nnnnnnnnnnlc0cch
n = unique node number
l = socket number on board
c = core
h = hyperthread
Only the "lc0cch" bits are written to the APICID register. The remaining bits are
supplied by having the get_apic_id() function "OR" the extra bits into the value
read from the APICID register. (Hmmm.. why not keep the ENTIRE APICID register
in per-cpu data....)
The x2apic-uv mode is recognized by the MADT table containing:
oem_id = "SGI"
oem_table_id = "UV-X"
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Introduce a function to read the local APIC_ID.
This change is in preparation for additional changes to
the APICID functions that will come in a later patch.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Indicate TSCs are unreliable as time sources if the platform is
a multi chassi ScaleMP vSMPowered machine.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is to match i386. The former name was cuter,
but the current is more meaningful and more general,
since cpu_id can be a logical id.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When acpi=off or there is no SRAT defined, apicid_to_node is got from K8
Northbridge PCI configuration space in k8_scan_nodes() in
arch/x86_64/mm/k8toplogy.c.
The problem is that it assumes bsp apic id is 0 at that point.
For four socket system with Quad core cpus installed, all cpus apic id
is offset by 4, and bsp apic id is 4.
For eight socket system with dual core cpus installed, all cpus apic id
is offset by 2, and bsp apic id is 2.
We need get boot_cpu_id --- bsp apic id, before k8_scan_nodes by called.
So create early_acpi_boot_init and early_get_smp_config for get boot_cpu_id.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
quad core 8 socket system will have apic id lifting.the apic id range could
be [4, 0x23]. and apic_is_clustered_box will think that need to three clusters
and that is larger than 2. So it is treated as a clustered_box.
and will get:
Marking TSC unstable due to TSCs unsynchronized
even if the CPUs have X86_FEATURE_CONSTANT_TSC set.
this quick fix will check if the cpu is from AMD.
but vsmp still needs that checking...
this patch is fix to make sure that vsmp not to be passed.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
when comparing the e820 direct from BIOS, and the one by kexec:
BIOS-provided physical RAM map:
- BIOS-e820: 0000000000000000 - 0000000000097400 (usable)
+ BIOS-e820: 0000000000000100 - 0000000000097400 (usable)
BIOS-e820: 0000000000097400 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000e6000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 00000000dffa0000 (usable)
- BIOS-e820: 00000000dffae000 - 00000000dffb0000 type 9
+ BIOS-e820: 00000000dffae000 - 00000000dffb0000 (reserved)
BIOS-e820: 00000000dffb0000 - 00000000dffbe000 (ACPI data)
BIOS-e820: 00000000dffbe000 - 00000000dfff0000 (ACPI NVS)
BIOS-e820: 00000000dfff0000 - 00000000e0000000 (reserved)
BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved)
- BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
=======> that is the local apic address... somewhere we lost it
BIOS-e820: 00000000ff700000 - 0000000100000000 (reserved)
BIOS-e820: 0000000100000000 - 0000004020000000 (usable)
found one entry about reserved is missing for the kernel by kexec.
it turns out init_apic_mappings is called before e820_reserve_resources
in setup_arch. but e820_reserve_resources is using request_resource.
it will not handle the conflicts.
there are three ways to fix it:
1. change request_resource in e820_reserve_resources to to insert_resource
2. move init_apic_mappings after e820_reserve_resources
3. use late_initcall to insert lapic resource.
this patch is using method 3, that is less intrusive.
in later version could consider to use method 1.
before patch
fed20000-ffffffff : PCI Bus #00
fee00000-fee00fff : Local APIC
fefff000-feffffff : pnp 00:09
ff700000-ffffffff : reserved
with patch will get map in first kernel
fed20000-ffffffff : PCI Bus #00
fee00000-fee00fff : Local APIC
fee00000-fee00fff : reserved
fefff000-feffffff : pnp 00:09
ff700000-ffffffff : reserved
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
quad core 8 socket system will have apic id lifting.the apic id range could
be [4, 0x23]. and apic_is_clustered_box will think that need to three clusters
and that is large than 2. So it is treated as clustered_box.
and will get
Marking TSC unstable due to TSCs unsynchronized
even the CPUs have X86_FEATURE_CONSTANT_TSC set.
this patch will check if the cpu is from AMD.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Change static bios_cpu_apicid array to a per_cpu data variable.
This includes using a static array used during initialization
similar to the way x86_cpu_to_apicid[] is handled.
There is one early use of bios_cpu_apicid in apic_is_clustered_box().
The other reference in cpu_present_to_apicid() is called after
smp_set_apicids() has setup the percpu version of bios_cpu_apicid.
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When the kernel panics early for some unrelated reason
there would be eventually an early exception inside panic because
clear_local_APIC tried to disable the not yet mapped APIC.
Check for that explicitely.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Change static bios_cpu_apicid array to a per_cpu data variable.
This includes using a static array used during initialization
similar to the way x86_cpu_to_apicid[] is handled.
There is one early use of bios_cpu_apicid in apic_is_clustered_box().
The other reference in cpu_present_to_apicid() is called after
smp_set_apicids() has setup the percpu version of bios_cpu_apicid.
[ mingo@elte.hu: build fix ]
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The check for an unitialized clock event device triggers, when the local
apic timer is registered as a dummy clock event device for broadcasting.
Preset the multiplicator to avoid a false positive.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Check the APIC timer calibration result for sanity. When the frequency
is out of range, issue a warning and disable the local APIC timer.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
White space and coding style clean up.
Make apic_32/64.c similar.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Its previous use in a call to on_each_cpu() was pointless, as at the
time that code gets executed only one CPU is online. Further, the
function can be __cpuinit, and for this to work without
CONFIG_HOTPLUG_CPU setup_nmi() must also get an attribute (this one
can even be __init; on 64-bits check_timer() also was lacking that
attribute).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The patch to suppress bitops-related warnings added a pile of ugly
casts. Many of these were related to the management of x86 CPU
capabilities. Clean these up by adding specific set/clear_cpu_cap
macros, and use them consistently.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Max Krasnyansky