Commit Graph

581 Commits

Author SHA1 Message Date
Konstantin Belousov
fa03524a9f Merge i386 and amd64 variants of mp_watchdog.c into x86/, there is no
difference between files.
For pc98, put x86/mp_x86.c into the same place as used by i386 file list.
Fix typo in comment.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-08-03 13:51:53 +00:00
Roger Pau Monné
23006680c7 Revert r291022: x86/intr: allow mutex recursion in intr_remove_handler
This was only needed for Xen, and a better way to deal with this issue has
been found, so this commit can be reverted.

Sponsored by:		Citrix Systems R&D
MFC after:		5 days
Reviewed by:		kib
Differential revision:	https://reviews.freebsd.org/D7363
2016-07-29 16:35:58 +00:00
Roger Pau Monné
35fdb32d86 xen-intr: fix removal of event channels during resume
Event channel handlers cannot be removed during resume because there might
be an interrupt thread running on a CPU currently blocked in the
cpususpend_handler, which prevents the call to intr_remove_handler from
finishing and completely freezes the system during resume. r291022 tried to
fix this by allowing recursion in intr_remove_handler, but that's clearly
not enough.

Instead don't remove the handlers at the interrupt resume phase, and let
each driver remove the handler by itself during resume. In order to do this,
change the opaque event channel handler cookie to use the global interrupt
vector instead of the event channel port. The event channel port cannot be
used because after resume all event channels are reset, and the port numbers
can change.

Sponsored by:		Citrix Systems R&D
MFC after:		5 days
2016-07-29 16:34:54 +00:00
Maxim Sobolev
e0cd4b7f6f Don't print same value twice, one in decimal once in hex. This makes
output more cryptic than it needs to be and wastes cpu cycles and
console bandwidth.
2016-07-18 03:59:03 +00:00
Mark Johnston
f4d0e9c95f Allow ACPI wakeup code and page tables to be stored in non-contiguous pages.
Since these pages are allocated from a narrow range of memory, this makes
the allocation more likely to succeed.

Suggested by:	kib
Reviewed by:	jkim, kib
MFC after:	2 months
Differential Revision:	https://reviews.freebsd.org/D7154
2016-07-14 00:38:04 +00:00
Eric Badger
fdb6320d45 Add explicit detection of KVM hypervisor
Set vm_guest to a new enum value (VM_GUEST_KVM) when kvm is detected and use
vm_guest in conditionals testing for KVM.

Also, fix a conditional checking if we're running in a VM which caught only
the generic VM case, but not more specific VMs (KVM, VMWare, etc.).  (Spotted
by: vangyzen).

Differential revision:	https://reviews.freebsd.org/D7172
Sponsored by:	Dell Inc.
Approved by:	kib (mentor), vangyzen (mentor)
Reviewed by:	alc
MFC after:	4 weeks
2016-07-13 19:19:18 +00:00
Roger Pau Monné
302244700f xen: automatically disable MSI-X interrupt migration
If the hypervisor version is smaller than 4.6.0. Xen commits 74fd00 and
70a3cb are required on the hypervisor side for this to be fixed, and those
are only included in 4.6.0, so stay on the safe side and disable MSI-X
interrupt migration on anything older than 4.6.0.

It should not cause major performance degradation unless a lot of MSI-X
interrupts are allocated.

Sponsored by:		Citrix Systems R&D
MFC after:		3 days
Reviewed by:		jhb
Differential revision:	https://reviews.freebsd.org/D7148
2016-07-12 08:43:09 +00:00
John Baldwin
be0319fd19 Add a tunable to disable migration of MSI-X interrupts.
The new 'machdep.disable_msix_migration' tunable can be set to 1 to
disable migration of MSI-X interrupts.

Xen versions prior to 4.6.0 do not properly handle updates to MSI-X
table entries after the initial write.  In particular, the operation
to unmask a table entry after updating it during migration is not
propagated to the "real" table for passthrough devices causing the
interrupt to remain masked.  At least some systems in EC2 are
affected by this bug when using SRIOV.  The tunable can be set in
loader.conf as a workaround.

Submitted by:	Jeremiah Lott <jlott@averesystems.com> (original patch)
Approved by:	re (marius)
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D6947
2016-06-24 22:49:32 +00:00
Mark Johnston
c722a89a63 Use M_NOWAIT when allocating memory for the ACPI wakeup handler.
If the allocation attempt fails, we may otherwise VM_WAIT after a failed
attempt to reclaim contiguous memory in the requested range. After r297466,
this results in the thread going to sleep, causing a hang during boot.

Reviewed by:	jkim, kib
Approved by:	re (gjb)
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D6945
2016-06-23 19:24:38 +00:00
Konstantin Belousov
0bf716e988 Trim some spaces to record correct commit message for the r301278.
Reduce number of iterations used for calibrating ICR read loop.  The
new number of iteration still gives the same ICR latency as before,
tested on Intel SandyBridge and Haswell machines, and on AMD.  But it
significantly reduces the unneeded pause on boot in some VMs, from ~10
secs to less then 1 sec.  It was reported to occur in bhyve on AMD
host.

Reported and tested by:	avg
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-06-03 18:23:45 +00:00
Konstantin Belousov
fcc1d8c9eb diff --git a/sys/x86/x86/local_apic.c b/sys/x86/x86/local_apic.c
index d8bda77..bb15df0 100644
--- a/sys/x86/x86/local_apic.c
+++ b/sys/x86/x86/local_apic.c
@@ -511,7 +511,7 @@ native_lapic_init(vm_paddr_t addr)
 	}

 #ifdef SMP
-#define	LOOPS	1000000
+#define	LOOPS	100000
 	/*
 	 * Calibrate the busy loop waiting for IPI ack in xAPIC mode.
 	 * lapic_ipi_wait_mult contains the number of iterations which
2016-06-03 18:05:18 +00:00
Ed Schouten
3a45c3d643 Implement _ALIGN() using internal integer types.
The existing version depends on register_t and uintptr_t, which are only
available when including headers such as <sys/types.h>. As this macro is
used by <sys/socket.h>, for example, it should be written in such a way
that it doesn't depend on those types.
2016-05-31 13:31:19 +00:00
Ed Schouten
78fe75bc28 Add missing dependency on <machine/_limits.h>.
In r227474, this header file was changed to define SIG_ATOMIC_{MIN,MAX}
in terms of LONG_{MIN,MAX}. Unlike all of the definitions in this header
file, LONG_{MIN,MAX} is provided by <limits.h>. Remove the dependency on
<limits.h> by using __LONG_{MIN,MAX} instead and including
<machine/_limits.h>.

This change is needed to make SIG_ATOMIC_{MIN,MAX} work without
including any other header files.
2016-05-31 08:38:24 +00:00
Ed Schouten
46f38226d7 Add missing dependency on <machine/_limits.h>.
This header uses __INT_MIN and __INT_MAX, which is provided by
<machine/_limits.h>. This is needed to make <stdint.h>'s WCHAR_MIN and
WCHAR_MAX work without including other headers as well.
2016-05-31 08:36:39 +00:00
Sepherosa Ziehau
98a68947d4 hyperv/vmbus: Rename ISR functions
MFC after:	1 week
Sponsored by:	Microsoft OSTC
Differential Revision:	https://reviews.freebsd.org/D6601
2016-05-31 04:47:53 +00:00
Konstantin Belousov
f159d7d6f0 Only calibrate ICR read loop when not in x2APIC mode. Run-time
switching between LAPIC modes is not supported, and there is no need
to wait for IPI ack in x2APIC mode.  So the calibrated delay is only
needed for !x2APIC.

This saves around a second of boot time on the real hardware for
x2APIC.

Sponsored by:	The FreeBSD Foundation
2016-05-26 09:09:11 +00:00
John Baldwin
10544b0951 Implement support for RF_UNMAPPED and bus_map/unmap_resource on x86.
Add implementations of bus_map/unmap_resource to the x86 nexus driver.
Change bus_activate/deactivate_resource to honor RF_UNMAPPED and to
use bus_map/unmap_resource to create/destroy the implicit mapping when
RF_UNMAPPED is not set.

Reviewed by:	cem
Differential Revision:	https://reviews.freebsd.org/D5237
2016-05-20 18:00:10 +00:00
John Baldwin
fdce57a042 Add an EARLY_AP_STARTUP option to start APs earlier during boot.
Currently, Application Processors (non-boot CPUs) are started by
MD code at SI_SUB_CPU, but they are kept waiting in a "pen" until
SI_SUB_SMP at which point they are released to run kernel threads.
SI_SUB_SMP is one of the last SYSINIT levels, so APs don't enter
the scheduler and start running threads until fairly late in the
boot.

This change moves SI_SUB_SMP up to just before software interrupt
threads are created allowing the APs to start executing kernel
threads much sooner (before any devices are probed).  This allows
several initialization routines that need to perform initialization
on all CPUs to now perform that initialization in one step rather
than having to defer the AP initialization to a second SYSINIT run
at SI_SUB_SMP.  It also permits all CPUs to be available for
handling interrupts before any devices are probed.

This last feature fixes a problem on with interrupt vector exhaustion.
Specifically, in the old model all device interrupts were routed
onto the boot CPU during boot.  Later after the APs were released at
SI_SUB_SMP, interrupts were redistributed across all CPUs.

However, several drivers for multiqueue hardware allocate N interrupts
per CPU in the system.  In a system with many CPUs, just a few drivers
doing this could exhaust the available pool of interrupt vectors on
the boot CPU as each driver was allocating N * mp_ncpu vectors on the
boot CPU.  Now, drivers will allocate interrupts on their desired CPUs
during boot meaning that only N interrupts are allocated from the boot
CPU instead of N * mp_ncpu.

Some other bits of code can also be simplified as smp_started is
now true much earlier and will now always be true for these bits of
code.  This removes the need to treat the single-CPU boot environment
as a special case.

As a transition aid, the new behavior is available under a new kernel
option (EARLY_AP_STARTUP).  This will allow the option to be turned off
if need be during initial testing.  I plan to enable this on x86 by
default in a followup commit in the next few days and to have all
platforms moved over before 11.0.  Once the transition is complete,
the option will be removed along with the !EARLY_AP_STARTUP code.

These changes have only been tested on x86.  Other platform maintainers
are encouraged to port their architectures over as well.  The main
things to check for are any uses of smp_started in MD code that can be
simplified and SI_SUB_SMP SYSINITs in MD code that can be removed in
the EARLY_AP_STARTUP case (e.g. the interrupt shuffling).

PR:		kern/199321
Reviewed by:	markj, gnn, kib
Sponsored by:	Netflix
2016-05-14 18:22:52 +00:00
Bjoern A. Zeeb
d68b7cfac5 Remove the extra _RD as _RDTUN already includes it.
Submitted by:	emaste
MFC after:	2 weeks
2016-05-13 15:29:40 +00:00
Bjoern A. Zeeb
2474dccf1a We already turn the AMD erratum383 workaround on for certain VM_GUEST_VM
if specific CPU features are not present.
Some simulation environments, e.g. gem5, have been found to require more
TLB management from the kernel in certain setups. It is currently unclear why.
Turning on the workaround_erratum383 seems to help and make problems (panics)
go away.
Given this is a fairly uncommon environment so far, allowing the workaround
to be manually enabled from loader in order to make debugging and comparing
traces easier, but also to allow gem5 run FreeBSD in X86 timing mode, seems
to be the least intrusive option for now until the issue if fully understood.

Sponsored by:	DARPA/AFRL
Reviewed by:	kib, alc (earlier)
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D6206
2016-05-13 15:11:17 +00:00
Bjoern A. Zeeb
c850971baf Allow orm(4) to be disabled from probing/attaching by a hints entry:
hint.orm.0.disabled=1

Suggested by:	jhb
Reviewed by:	jhb
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D6307
2016-05-10 22:28:06 +00:00
Edward Tomasz Napierala
084d207584 Remove misc NULL checks after M_WAITOK allocations.
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
2016-05-10 10:26:07 +00:00
John Baldwin
8d791e5af1 Add a new bus method to fetch device-specific CPU sets.
bus_get_cpus() returns a specified set of CPUs for a device.  It accepts
an enum for the second parameter that indicates the type of cpuset to
request.  Currently two valus are supported:

 - LOCAL_CPUS (on x86 this returns all the CPUs in the package closest to
   the device when DEVICE_NUMA is enabled)
 - INTR_CPUS (like LOCAL_CPUS but only returns 1 SMT thread for each core)

For systems that do not support NUMA (or if it is not enabled in the kernel
config), LOCAL_CPUS fails with EINVAL.  INTR_CPUS is mapped to 'all_cpus'
by default.  The idea is that INTR_CPUS should always return a valid set.

Device drivers which want to use per-CPU interrupts should start using
INTR_CPUS instead of simply assigning interrupts to all available CPUs.
In the future we may wish to add tunables to control the policy of
INTR_CPUS (e.g. should it be local-only or global, should it ignore
SMT threads or not).

The x86 nexus driver exposes the internal set of interrupt CPUs from the
the x86 interrupt code via INTR_CPUS.

The ACPI bus driver and PCI bridge drivers use _PXM to return a suitable
LOCAL_CPUS set when _PXM exists and DEVICE_NUMA is enabled.  They also and
the global INTR_CPUS set from the nexus driver with the per-domain set from
_PXM to generate a local INTR_CPUS set for child devices.

Compared to the r298933, this version uses 'struct _cpuset' in
<sys/bus.h> instead of 'cpuset_t' to avoid requiring <sys/param.h>
(<sys/_cpuset.h> still requires <sys/param.h> for MAXCPU even though
<sys/_bitset.h> does not after recent changes).
2016-05-09 20:50:21 +00:00
Eric van Gyzen
2db0699d88 Work around (ignore) broken SRAT tables
Instead of panicking when parsing an invalid ACPI SRAT table,
just ignore it, effectively disabling NUMA.

https://lists.freebsd.org/pipermail/freebsd-current/2016-May/060984.html

Reported and tested by:	 Bill O'Hanlon (bill.ohanlon at gmail.com)
Reviewed by:	jhb
MFC after:	1 week
Relnotes:	If dmesg shows "SRAT: Duplicate local APIC ID",
                try updating your BIOS to fix NUMA support.
Sponsored by:	Dell Inc.
2016-05-03 20:14:04 +00:00
John Baldwin
8a08b7d36b Revert bus_get_cpus() for now.
I really thought I had run this through the tinderbox before committing,
but many places need <sys/types.h> -> <sys/param.h> for <sys/bus.h> now.
2016-05-03 01:17:40 +00:00
John Baldwin
bc153c692f Add a new bus method to fetch device-specific CPU sets.
bus_get_cpus() returns a specified set of CPUs for a device.  It accepts
an enum for the second parameter that indicates the type of cpuset to
request.  Currently two valus are supported:

 - LOCAL_CPUS (on x86 this returns all the CPUs in the package closest to
   the device when DEVICE_NUMA is enabled)
 - INTR_CPUS (like LOCAL_CPUS but only returns 1 SMT thread for each core)

For systems that do not support NUMA (or if it is not enabled in the kernel
config), LOCAL_CPUS fails with EINVAL.  INTR_CPUS is mapped to 'all_cpus'
by default.  The idea is that INTR_CPUS should always return a valid set.

Device drivers which want to use per-CPU interrupts should start using
INTR_CPUS instead of simply assigning interrupts to all available CPUs.
In the future we may wish to add tunables to control the policy of
INTR_CPUS (e.g. should it be local-only or global, should it ignore
SMT threads or not).

The x86 nexus driver exposes the internal set of interrupt CPUs from the
the x86 interrupt code via INTR_CPUS.

The ACPI bus driver and PCI bridge drivers use _PXM to return a suitable
LOCAL_CPUS set when _PXM exists and DEVICE_NUMA is enabled.  They also and
the global INTR_CPUS set from the nexus driver with the per-domain set from
_PXM to generate a local INTR_CPUS set for child devices.

Reviewed by:	wblock (manpage)
Differential Revision:	https://reviews.freebsd.org/D5519
2016-05-02 18:00:38 +00:00
Roger Pau Monné
f65466eb3a atrtc: export function to set RTC
This is going to be used by the Xen clock on Dom0 in order to set the RTC of
the host. The current logic in atrtc_settime is moved to atrtc_set and the
unused device_t parameter is removed from the atrtc_set function call so it
can be safely used by other callers.

Sponsored by:		Citrix Systems R&D
Reviewed by:		kib, jhb
Differential revision:	https://reviews.freebsd.org/D6067
2016-05-02 16:14:55 +00:00
Pedro F. Giffuni
d9c9c81c08 sys: use our roundup2/rounddown2() macros when param.h is available.
rounddown2 tends to produce longer lines than the original code
and when the code has a high indentation level it was not really
advantageous to do the replacement.

This tries to strike a balance between readability using the macros
and flexibility of having the expressions, so not everything is
converted.
2016-04-21 19:57:40 +00:00
Conrad Meyer
3765b80993 SRAT: Don't overflow domain_pxm table
If we reached MAXMEMDOM, we would previously try to insert an additional
element and only detect overflow after causing (probably trivial) memory
overflow.  Instead, detect the ndomain > MAXMEMDOM case before we write past
the end.

Reported by:	Coverity
CID:		1354783
Sponsored by:	EMC / Isilon Storage Division
2016-04-20 01:10:07 +00:00
Pedro F. Giffuni
ea24b0561f X86: use our nitems() macro when it is avaliable through param.h.
No functional change, only trivial cases are done in this sweep,

Discussed in:	freebsd-current
2016-04-19 23:41:46 +00:00
Konstantin Belousov
e164cafc69 Add hw.dmar.batch_coalesce tunable/sysctl, which specifies rate at
which queued invalidation completion interrupt is requested with
regard to the queued invalidation requests.  In other words, setting
the value of the knob to N requests completion interrupt after N items
are processed.  Existing behaviour is restored by setting
hw.dmar.batch_coalesce=1.

The knob significantly decreases the DMAR qi interrupt rate at the
cost of slightly longer DMAR map entries recycling.

Sponsored by:	The FreeBSD Foundation
2016-04-17 10:56:56 +00:00
Konstantin Belousov
c5c20928d3 Add x86 CPU features definitions published in the Intel SDM rev. 58.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-04-16 06:07:13 +00:00
Konstantin Belousov
9e297f96d4 Always calculate divisor for the counter mode of LAPIC timer. Even if
initially configured in the TSC deadline mode, eventtimer subsystem
can be switched to periodic, and then DCR register is loaded with
unitialized value.

Reset the LAPIC eventtimer frequency and min/max periods when changing
between deadline and counted periodic modes.

Reported and tested by:	Vladimir Zakharov <zakharov.vv@gmail.com>
Sponsored by:	The FreeBSD Foundation
2016-04-15 14:36:38 +00:00
Roger Pau Monné
9b44287ce5 busdma/bounce: revert r292255
Revert r292255 because it can create bounced regions without contiguous
page offsets, which is needed for USB devices.

Another solution would be to force bouncing the full buffer always (even
when only one page requires bouncing), but this seems overly complicated and
unnecessary, and it will probably involve using more bounce pages than the
current code.

Reported by: phk
2016-04-15 09:21:50 +00:00
Pedro F. Giffuni
a3269b0863 x86: for pointers replace 0 with NULL.
These are mostly cosmetical, no functional change.

Found with devel/coccinelle.
2016-04-14 17:04:06 +00:00
Warner Losh
bd3bce41db Deprecate using hints.acpi.0.rsdp to communicate the RSDP to the
system. This uses the hints mechnanism. This mostly works today
because when there's no static hints (the default), this value can be
fetched from the hint. When there is a static hints file, the hint
passed from the boot loader to the kernel is ignored, but for the BIOS
case we're able to find it anyway. However, with UEFI, the fallback
doesn't work, so we get a panic instead.

Switch to acpi.rsdp and use TUNABLE_ULONG_FETCH instead. Continue to
generate the old values to allow for transitions. In addition, fall
back to the old method if the new method isn't present.

Add comments about all this.

Differential Revision: https://reviews.freebsd.org/D5866
2016-04-14 04:59:51 +00:00
Andriy Gapon
0d63fc3ed8 re-enable AMD Topology extension on certain models if disabled by BIOS
Some BIOSes disable AMD Topology extension on AMD Family 15h notebook
processors.  We re-enable the extension, so that we can properly discover
core and cache topology.  Linux seems to do the same.

Reported by:	Johannes Dieterich <dieterich.joh@gmail.com>
Reviewed by:	jhb, kib
Tested by:	Johannes Dieterich <dieterich.joh@gmail.com>
		(earlier version)
MFC after:	3 weeks
Differential Revision:	https://reviews.freebsd.org/D5883
2016-04-12 13:30:39 +00:00
Pedro F. Giffuni
74b8d63dcc Cleanup unnecessary semicolons from the kernel.
Found with devel/coccinelle.
2016-04-10 23:07:00 +00:00
John Baldwin
62d70a8174 Add more fine-grained kernel options for NUMA support.
VM_NUMA_ALLOC is used to enable use of domain-aware memory allocation in
the virtual memory system.  DEVICE_NUMA is used to enable affinity
reporting for devices such as bus_get_domain().

MAXMEMDOM must still be set to a value greater than for any NUMA support
to be effective.  Note that 'cpuset -gd' always works if MAXMEMDOM is
enabled and the system supports NUMA.

Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D5782
2016-04-09 13:58:04 +00:00
Sepherosa Ziehau
19605ff758 xen: Set ipi_{alloc,free} even for UP
This keeps XEN apic_ops aligned w/ x86's.

Suggested by:	kib, jhb
Reviewed by:	jhb, royger
Sponsored by:	Microsoft OSTC
Differential Revision:	https://reviews.freebsd.org/D5871
2016-04-07 07:00:00 +00:00
Sepherosa Ziehau
8b0986c27f x86: Allow interrupt vector allocation/free even on UP
It is needed by the hypervisor FreeBSD guest to allocate/free private
interrupt vectors.

Reviewed by:	kib, jhb, Dexuan Cui <decui microsoft com>
Sponsored by:	Microsoft OSTC
Differential Revision:	https://reviews.freebsd.org/D5849
2016-04-07 06:36:03 +00:00
Andriy Gapon
c77702de74 x86 topo: add some comments, descriptions and references to documentation
Plus a minor cosmetic change.

MFC after:	1 month
2016-04-05 10:36:40 +00:00
Andriy Gapon
4725e6bff3 new x86 smp topology detection code
Previously, the code determined a topology of processing units
(hardware threads, cores, packages) and then deduced a cache topology
using certain assumptions.  The new code builds a topology that
includes both processing units and caches using the information
provided by the hardware.

At the moment, the discovered full topology is used only to creeate
a scheduling topology for SCHED_ULE.
There is no KPI for other kernel uses.

Summary:
- based on APIC ID derivation rules for Intel and AMD CPUs
- can handle non-uniform topologies
- requires homogeneous APIC ID assignment (same bit widths for ID
  components)
- topology for dual-node AMD CPUs may not be optimal
- topology for latest AMD CPU models may not be optimal as the code is
  several years old
- supports only thread/package/core/cache nodes

Todo:
  - AMD dual-node processors
  - latest AMD processors
  - NUMA nodes
  - checking for homogeneity of the APIC ID assignment across packages
  - more flexible cache placement within topology
  - expose topology to userland, e.g., via sysctl nodes

Long term todo:
  - KPI for CPU sharing and affinity with respect to various resources
    (e.g., two logical processors may share the same FPU, etc)

Reviewed by:	mav
Tested by:	mav
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D2728
2016-04-04 16:09:29 +00:00
John Baldwin
2b1e924b69 Move i386/i386/autoconf.c to sys/x86/x86 and use it on both amd64 and i386. 2016-04-03 23:03:54 +00:00
Konstantin Belousov
5c8e0b3bcb Style(9), use tabs for the #define LOOPS line.
Print unsigned values with %u.
Make code slightly more compact by inlining loop limit.

Noted by:	bde
Sponsored by:	The FreeBSD Foundation
2016-04-01 08:47:23 +00:00
Konstantin Belousov
0df87548b9 Type of the interrupt handlers on x86 cannot be expressed in C.
Simplify and unify placeholder type definitions.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D5771
2016-03-29 19:56:48 +00:00
Konstantin Belousov
d317106ce2 Fix several bugs in r297374:
- fix UP build [1]
- do not obliterate initial reading of rdtsc by the loop counter [2]
- restore the meaning of the argument -1 to native_lapic_ipi_wait()
  as wait until LAPIC acknowledge without timeout
- correct formula for calculating loop iteration count for 1us, it was
  inverted, and ensure that even on unlikely slow CPUs at least one
  check for ack is performed.

Reported by:	Michael Butler <imb@protected-networks.net> [1], rpokala[2],
	jhb[3]
Tested by:	Michael Butler
Pointy hat to:	kib
Sponsored by:	The FreeBSD Foundation
2016-03-29 19:54:13 +00:00
Konstantin Belousov
998e1ef11f Calibrate the frequency of the of the native_lapic_ipi_wait() loop,
and avoid a delay while waiting for IPI delivery acknowledgement in
xAPIC mode.  This makes the loop exit immediately after the delivery
bit in APIC_ICR register is set, instead of waiting for some
microseconds.

We only need to ensure that some amount of time is allowed for the
LAPIC to react to the command, and we need that the wait time is
finite and reasonable.  For that reasons, it is irrelevant if the CPU
frequency or throttling decrease the speed and make the loop,
calibrated for full CPU speed at boot time, execute somewhat slower.

Discussed with:	bde, jhb
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
2016-03-29 08:44:56 +00:00
Konstantin Belousov
d58c003a8a Use ANSI function definition.
Sponsored by:	The FreeBSD Foundation
2016-03-29 08:31:34 +00:00
Konstantin Belousov
841d5e0151 Do not load LAPIC_DCR_TIMER with an undefined value. If we are in the
deadline mode the divide configuration is not used and
lapic_timer_divisor is not set.

Reported by:	dhw, mav
Tested by:	mav
Sponsored by:	The FreeBSD Foundation
2016-03-28 15:05:00 +00:00