Impact: optimize APIC IPI related barriers
Uncached MMIO accesses for xapic are inherently serializing and hence
we don't need explicit barriers for xapic IPI paths.
x2apic MSR writes/reads don't have serializing semantics and hence need
a serializing instruction or mfence, to make all the previous memory
stores globally visisble before the x2apic msr write for IPI.
Add x2apic_wrmsr_fence() in flush tlb path to x2apic specific paths.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "steiner@sgi.com" <steiner@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
LKML-Reference: <1237313814.27006.203.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix spurious IRQs
During irq migration, we send a low priority interrupt to the previous
irq destination. This happens in non interrupt-remapping case after interrupt
starts arriving at new destination and in interrupt-remapping case after
modifying and flushing the interrupt-remapping table entry caches.
This low priority irq cleanup handler can cleanup multiple vectors, as
multiple irq's can be migrated at almost the same time. While
there will be multiple invocations of irq cleanup handler (one cleanup
IPI for each irq migration), first invocation of the cleanup handler
can potentially cleanup more than one vector (as the first invocation can
see the requests for more than vector cleanup). When we cleanup multiple
vectors during the first invocation of the smp_irq_move_cleanup_interrupt(),
other vectors that are to be cleanedup can still be pending in the local
cpu's IRR (as smp_irq_move_cleanup_interrupt() runs with interrupts disabled).
When we are ready to unhook a vector corresponding to an irq, check if that
vector is registered in the local cpu's IRR. If so skip that cleanup and
do a self IPI with the cleanup vector, so that we give a chance to
service the pending vector interrupt and then cleanup that vector
allocation once we execute the lowest priority handler.
This fixes spurious interrupts seen when migrating multiple vectors
at the same time.
[ This is apparently possible even on conventional xapic, although to
the best of our knowledge it has never been seen. The stable
maintainers may wish to consider this one for -stable. ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: stable@kernel.org
Impact: fix possible race
save_mask_IO_APIC_setup() was using non atomic memory allocation while getting
called with interrupts disabled. Fix this by splitting this into two different
function. Allocation part save_IO_APIC_setup() now happens before
disabling interrupts.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
Clean up #ifdefs and replace them with helper functions.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: simplification
In the current code, for level triggered migration, we need to modify the
io-apic RTE with the update vector information, along with modifying interrupt
remapping table entry(IRTE) with vector and destination. This is to ensure that
remote IRR bit inthe IOAPIC RTE gets cleared when the cpu does EOI.
With this patch, for level triggered, we eliminate the io-apic RTE modification
(with the updated vector information), by using a virtual vector (io-apic pin
number). Real vector that is used for interrupting cpu will be coming from
the interrupt-remapping table entry. Trigger mode in the IRTE will always be
edge, and the actual level or edge trigger will be setup in the IO-APIC RTE.
So a level triggered interrupt will appear as an edge to the local apic
cpu but still as level to the IO-APIC.
With this change, level irq migration can be done by simply modifying
the interrupt-remapping table entry with out changing the io-apic RTE.
And as the interrupt appears as edge at the cpu, in addition to do the
local apic EOI, we need to do IO-APIC directed EOI to clear the remote
IRR bit in the IO-APIC RTE.
This simplies the irq migration in the presence of interrupt-remapping.
Idea-by: Rajesh Sankaran <rajesh.sankaran@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup, paranoia
We were not clearing the local APIC in clear_local_APIC() in the
presence of x2apic. Fix it.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: make kexec work with x2apic
disable_IO_APIC() gets called during crashdump aswell, which configures the
IO-APIC/LAPIC so that legacy interrupts can be delivered for the kexec'd kernel.
In the presence of interrupt-remapping, we need to change the
interrupt-remapping configuration aswell as modifying IO-APIC for virtual wire
B mode.
To keep things simple during the crash, use virtual wire A mode
(for which we don't need to touch io-apic and interrupt-remapping tables).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: interface augmentation (not yet used)
Enable fault handling flow for intr-remapping aswell. Fault handling
code now shared by both dma-remapping and intr-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
We are removing cpumask_t in favour of struct cpumask: mainly as a
marker of what code is now CONFIG_CPUMASK_OFFSTACK-safe.
The only non-trivial change here is vector_allocation_domain():
explicitly clear the mask and set the first word, rather than using
assignment.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Impact: cleanup
It's not legal to do assignments into cpumask_var_t; they will soon be of
variable length.
So explicitly clear the mask and set the first word, rather than using
assignment.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Impact: cleanup, remove cpumask from stack
summit_send_IPI_allbutself might as well call
default_send_IPI_mask_allbutself_logical(). Also change cpumask_t to
struct cpumask and &cpu_online_map to cpu_online_mask while here.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y
I *think* every path calls check_nmi_watchdog before using the
watchdog, so that's the right place for the initialization.
If that's wrong, we'll get a nice NULL-deref with
CONFIG_CPUMASK_OFFSTACK=y, and have uncovered another bug.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Impact: cleanup
(Thanks to Al Viro for reminding me of this, via Ingo)
CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so:
#define CPU_MASK_ALL (cpumask_t) { { ... } }
Taking the address of such a temporary is questionable at best,
unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added
CPU_MASK_ALL_PTR:
#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL)
Which formalizes this practice. One day gcc could bite us over this
usage (though we seem to have gotten away with it so far).
So replace everywhere which used &CPU_MASK_ALL or CPU_MASK_ALL_PTR
with the modern "cpu_all_mask" (a real const struct cpumask *), and remove
CPU_MASK_ALL_PTR altogether.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mike Travis <travis@sgi.com>
Remove __cpuinitdata section placement for translation_table
structure, since it is referenced from a functions within .text.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Remove __init section placement for some functions/data, so that
we don't get section mismatch warnings.
Also make inline function instead of empty setup_summit macro.
[v2]
One of them was not caught by
DEBUG_SECTION_MISMATCH=y
magic. Fix it.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Remove __init section placement for some functions, so that we don't
get section mismatch warnings.
[v2]:
2 of them were not caught by
DEBUG_SECTION_MISMATCH=y
magic. Fix it.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Perform same-cluster checking even for masks with all (nr_cpu_ids)
bits set and report correct apicid on success instead.
While at it, convert it to for_each_cpu and newer cpumask api.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Perform same-cluster checking even for masks with all (nr_cpu_ids)
bits set and report BAD_APICID on failure.
While at it, convert it to for_each_cpu.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove es7000_cpu_mask_to_apicid_cluster completely, because it's
almost the same as es7000_cpu_mask_to_apicid except 2 code paths.
One of them is about to be removed soon, the another should be
BAD_APICID (it's a fail path).
The _cluster one was not invoked on apic->cpu_mask_to_apicid_and
anyway, since there was no _cluster_and variant.
Also use newer cpumask functions.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The ones which go only into struct apic are de-inlined
by compiler anyway, so remove the inline specifier from them.
Afterwards, remove bigsmp_setup_portio_remap completely as it
is unused.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/apic/es7000_32.c:702: error: 'es7000_acpi_madt_oem_check_cluster' undeclared here (not in a function)
Provide a es7000_acpi_madt_oem_check_cluster() definition in the !ACPI
case too.
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: build fix
init_deasserted is only available on SMP. Make the secondary-wakeup
function conditional on SMP.
Also clean up the file some.
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
- rename apic->wakeup_cpu to apic->wakeup_secondary_cpu, to
make it apparent that this is an SMP-only method
- handle NULL ->wakeup_secondary_cpus to mean the default INIT
wakeup sequence - this allows simplification of the APIC
driver templates.
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
x86_quirks->update_apic() calling looks crazy. so try to remove it:
1. every apic take wakeup_cpu member directly
2. separate es7000_apic to es7000_apic_cluster
3. use uv_wakeup_cpu directly
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The ones which go only into struct genapic are de-inlined
by compiler anyway, so remove the inline specifier from them.
Afterwards, remove summit_setup_portio_remap completely as it
is unused.
Remove inline also from summit_cpu_mask_to_apicid, since it's
not worth it (it is used in struct genapic too).
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use BAD_APICID instead of 0xFF constants in summit_cpu_mask_to_apicid.
Also remove bogus comments about what we actually return.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Make x86_quirks support more transparent. The highlevel
methods are now named:
extern void x86_quirk_pre_intr_init(void);
extern void x86_quirk_intr_init(void);
extern void x86_quirk_trap_init(void);
extern void x86_quirk_pre_time_init(void);
extern void x86_quirk_time_init(void);
This makes it clear that if some platform extension has to
do something here that it is considered ... weird, and is
discouraged.
Also remove arch_hooks.h and move it into setup.h (and other
header files where appropriate).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If BIOS hands over the control to OS in legacy xapic mode, select
legacy xapic related ops in the early apic probe and shift to x2apic
ops later in the boot sequence, only after enabling x2apic mode.
If BIOS hands over the control in x2apic mode, select x2apic related
ops in the early apic probe.
This fixes the early boot panic, where we were selecting x2apic ops,
while the cpu is still in legacy xapic mode.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: build fix, cleanup
A couple of arch setup callbacks were mistakenly in apic_32.c, breaking
the build.
Also simplify the code a bit.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move the 32-bit extended-arch APIC drivers to arch/x86/kernel/apic/
too, and rename apic_64.c to probe_64.c.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.
Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.
Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
