when pmap_demote_pde() allocates a page table page to implement a
user-space demotion, it must increment the pmap's resident page count.
Not doing so, can lead to an underflow during address space termination
that causes pmap_remove() to exit prematurely, before it has destroyed
all of the mappings within the specified range. The ultimate effect or
symptom of this error is an assertion failure in vm_page_free_toq()
because the page being freed is still mapped.
This error is only possible when superpage promotion is enabled. Thus,
it only affects FreeBSD versions greater than 7.2.
Tested by: pho, alc
Reviewed by: alc
Approved by: re (rwatson)
MFC after: 1 week
- Provide lapic_disable_pmc(), lapic_enable_pmc(), and lapic_reenable_pmc()
routines in the local APIC code that the hwpmc(4) driver can use to
manage the local APIC PMC interrupt vector.
- Do not enable the local APIC PMC interrupt vector by default when
HWPMC_HOOKS is enabled. Instead, the hwpmc(4) driver explicitly
enables the interrupt when it is succesfully initialized and disables
the interrupt when it is unloaded. This avoids enabling the interrupt
on unsupported CPUs which may result in spurious NMIs.
Reported by: rnoland
Reviewed by: jkoshy
Approved by: re (kib)
MFC after: 2 weeks
has proven to have a good effect when entering KDB by using a NMI,
but it completely violates all the good rules about interrupts
disabled while holding a spinlock in other occasions. This can be the
cause of deadlocks on events where a normal IPI_STOP is expected.
* Adds an new IPI called IPI_STOP_HARD on all the supported architectures.
This IPI is responsible for sending a stop message among CPUs using a
privileged channel when disponible. In other cases it just does match a
normal IPI_STOP.
Right now the IPI_STOP_HARD functionality uses a NMI on ia32 and amd64
architectures, while on the other has a normal IPI_STOP effect. It is
responsibility of maintainers to eventually implement an hard stop
when necessary and possible.
* Use the new IPI facility in order to implement a new userend SMP kernel
function called stop_cpus_hard(). That is specular to stop_cpu() but
it does use the privileged channel for the stopping facility.
* Let KDB use the newly introduced function stop_cpus_hard() and leave
stop_cpus() for all the other cases
* Disable interrupts on CPU0 when starting the process of APs suspension.
* Style cleanup and comments adding
This patch should fix the reboot/shutdown deadlocks many users are
constantly reporting on mailing lists.
Please don't forget to update your config file with the STOP_NMI
option removal
Reviewed by: jhb
Tested by: pho, bz, rink
Approved by: re (kib)
a device pager (OBJT_DEVICE) object in that it uses fictitious pages to
provide aliases to other memory addresses. The primary difference is that
it uses an sglist(9) to determine the physical addresses for a given offset
into the object instead of invoking the d_mmap() method in a device driver.
Reviewed by: alc
Approved by: re (kensmith)
MFC after: 2 weeks
established, OS shall flush the caches on all processors that may have
used the mapping previously. This operation is not needed if processors
support self-snooping. If not, but clflush instruction is implemented
on the CPU, series of the clflush can be used on the mapping region.
Otherwise, we have to flush the whole cache. The later operation is very
expensive, and AMD-made CPUs do not have self-snooping.
Implement cache flush for remapped region by using clflush for amd64,
when supported by CPU.
Proposed and reviewed by: alc
Approved by: re (kensmith)
amd64 and i386. Essentially, fictitious pages provide a mechanism for
creating aliases for either normal or device-backed pages. Therefore,
pmap_page_set_memattr() on a fictitious page needn't update the direct
map or flush the cache. Such actions are the responsibility of the
"primary" instance of the page or the device driver that "owns" the
physical address. For example, these actions are already performed by
pmap_mapdev().
The device pager needn't restore the memory attributes on a fictitious
page before releasing it. It's now pointless.
Add pmap_page_set_memattr() to the Xen pmap.
Approved by: re (kib)
configuring machine-dependent memory attributes...":
Don't set the memory attribute for a "real" page that is allocated to
a device object in vm_page_alloc(). It is a pointless act, because
the device pager replaces this "real" page with a "fake" page and sets
the memory attribute on that "fake" page.
Eliminate pointless code from pmap_cache_bits() on amd64.
Employ the "Self Snoop" feature supported by some x86 processors to
avoid cache flushes in the pmap.
Approved by: re (kib)
dependent memory attributes:
Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the
fact that there are machine-dependent memory attributes that have
nothing to do with controlling the cache's behavior.
Introduce vm_object_set_memattr() for setting the default memory
attributes that will be given to an object's pages.
Introduce and use pmap_page_{get,set}_memattr() for getting and
setting a page's machine-dependent memory attributes. Add full
support for these functions on amd64 and i386 and stubs for them on
the other architectures. The function pmap_page_set_memattr() is also
responsible for any other machine-dependent aspects of changing a
page's memory attributes, such as flushing the cache or updating the
direct map. The uses include kmem_alloc_contig(), vm_page_alloc(),
and the device pager:
kmem_alloc_contig() can now be used to allocate kernel memory with
non-default memory attributes on amd64 and i386.
vm_page_alloc() and the device pager will set the memory attributes
for the real or fictitious page according to the object's default
memory attributes.
Update the various pmap functions on amd64 and i386 that map pages to
incorporate each page's memory attributes in the mapping.
Notes: (1) Inherent to this design are safety features that prevent
the specification of inconsistent memory attributes by different
mappings on amd64 and i386. In addition, the device pager provides a
warning when a device driver creates a fictitious page with memory
attributes that are inconsistent with the real page that the
fictitious page is an alias for. (2) Storing the machine-dependent
memory attributes for amd64 and i386 as a dedicated "int" in "struct
md_page" represents a compromise between space efficiency and the ease
of MFCing these changes to RELENG_7.
In collaboration with: jhb
Approved by: re (kib)
net80211 wireless stack. This work is based on the March 2009 D3.0 draft
standard. This standard is expected to become final next year.
This includes two main net80211 modules, ieee80211_mesh.c
which deals with peer link management, link metric calculation,
routing table control and mesh configuration and ieee80211_hwmp.c
which deals with the actually routing process on the mesh network.
HWMP is the mandatory routing protocol on by the mesh standard, but
others, such as RA-OLSR, can be implemented.
Authentication and encryption are not implemented.
There are several scripts under tools/tools/net80211/scripts that can be
used to test different mesh network topologies and they also teach you
how to setup a mesh vap (for the impatient: ifconfig wlan0 create
wlandev ... wlanmode mesh).
A new build option is available: IEEE80211_SUPPORT_MESH and it's enabled
by default on GENERIC kernels for i386, amd64, sparc64 and pc98.
Drivers that support mesh networks right now are: ath, ral and mwl.
More information at: http://wiki.freebsd.org/WifiMesh
Please note that this work is experimental. Also, please note that
bridging a mesh vap with another network interface is not yet supported.
Many thanks to the FreeBSD Foundation for sponsoring this project and to
Sam Leffler for his support.
Also, I would like to thank Gateworks Corporation for sending me a
Cambria board which was used during the development of this project.
Reviewed by: sam
Approved by: re (kensmith)
Obtained from: projects/mesh11s
usermode, it generates GPF, that is mirrored to user mode as SIGSEGV.
The offending register in mcontext should contain the value loading of
which generated the GPF, and it is so on i386. On amd64, we currently
report segment descriptor in tf_err, while segment register contains the
corrected value loaded by trap handler.
Fix the issue by behaving like i386, reloading segment register in trap
frame after signal frame is pushed onto user stack.
Noted and tested by: pho
Approved by: re (kensmith)
return path only when neither thread was context switched while
executing syscall code nor syscall explicitely modified LDT or MSRs.
Save segment registers in trap handlers before interrupts are enabled,
to not allow context switches to happen before registers are saved.
Use separated byte in pcb for indication of fast/full return, since
pcb_flags are not synchronized with context switches.
The change puts back syscall microbenchmark numbers that were slowed
down after commit of the support for LDT on amd64.
Reviewed by: jeff
Tested (and tested, and tested ...) by: pho
Approved by: re (kensmith)
to simultaneously change the PAT setting for the same pages within the
direct map region. This may require the demotion of a 2MB page mapping and
the allocation of a page table page. This revision gives the highest
possible priority (VM_ALLOC_INTERRUPT) to this page allocation, so that
pmap_change_attr() is less likely to fail. (In general, kernel page table
page allocations have the highest priority, so this is not creating a new
precedent.)
(Demotion of 1GB page mappings within the direct map already specifies
VM_ALLOC_INTERRUPT to vm_page_alloc(), so only pmap_demote_pde() must be
changed.)
Approved by: re (kib)
when the interrupt was moved from one CPU to another. If the interrupt was
enabled, then the old IDT vector needs to be disabled and the new IDT vector
needs to be enabled. This was mostly masked prior to the recent MSI changes
since in the older code almost all allocated IDT vectors were already enabled
and the enabled vectors on the BSP during boot covered enough of the IDT
range. However, after the MSI changes, MSI interrupts that were allocated
but not enabled (e.g. DRM with MSI) during boot could result in an allocated
IDT vector that wasn't enabled. The round-robin at the end of boot could
place another interrupt at the same IDT vector without enabling the IDT
vector causing trap 30 faults.
Fix this by explicitly disabling/enabling the old and new IDT vectors for
enabled interrupt sources when moving an interrupt between CPUs via the
pic_assign_cpu() method. While here, fix a bug in my earlier changes so
that an I/O APIC interrupt pin is left unchanged if ioapic_assign_cpu()
fails to allocate a new IDT vector and returns ENOSPC.
Approved by: re (kensmith)
o add to platforms where it was missing (arm, i386, powerpc, sparc64, sun4v)
o define as "1" on amd64 and i386 where there is no restriction
o make the type returned consistent with ALIGN
o remove _ALIGNED_POINTER
o make associated comments consistent
Reviewed by: bde, imp, marcel
Approved by: re (kensmith)
More applications (including Firefox) seem to depend on this nowadays,
so not having this enabled by default is a bad idea.
Proposed by: miwi
Patch by: Florian Smeets <flo kasimir com>
Approved by: re (kib)
- For x86, change the interrupt source method to assign an interrupt source
to a specific CPU to return an error value instead of void, thus allowing
it to fail.
- If moving an interrupt to a CPU fails due to a lack of IDT vectors in the
destination CPU, fail the request with ENOSPC rather than panicing.
- For MSI interrupts on x86 (but not MSI-X), only allow cpuset to be used
on the first interrupt in a group. Moving the first interrupt in a group
moves the entire group.
- Use the icu_lock to protect intr_next_cpu() on x86 instead of the
intr_table_lock to fix a LOR introduced in the last set of MSI changes.
- Add a new privilege PRIV_SCHED_CPUSET_INTR for using cpuset with
interrupts. Previously, binding an interrupt to a CPU only performed a
privilege check if the interrupt had an interrupt thread. Interrupts
without a thread could be bound by non-root users as a result.
- If an interrupt event's assign_cpu method fails, then restore the original
cpuset mask for the associated interrupt thread.
Approved by: re (kib)
specific macros for each audit argument type. This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).
In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.
Suggested by: brooks
Approved by: re (kib)
Obtained from: TrustedBSD Project
MFC after: 1 week
required by video card drivers. Specifically, this change introduces
vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all
architectures. In addition, this changes adds a vm_cache_mode_t parameter
to kmem_alloc_contig() and vm_phys_alloc_contig(). These will be the
interfaces for allocating mapped kernel memory and physical memory,
respectively, with non-default cache modes.
In collaboration with: jhb
This is mostly important for the multiple MSI message case where the
IDT vectors for the entire group need to be allocated together. This
also restores the assumptions made by the PCI bus code that it could
invoke PCIB_MAP_MSI() once MSI vectors were allocated.
- To avoid whiplash with CPU assignments, change the way that CPUs are
assigned to interrupt sources on activation. Instead of assigning the
CPU via pic_assign_cpu() before calling enable_intr(), allow the
different interrupt source drivers to ask the MD interrupt code which
CPU to use when they allocate an IDT vector. I/O APIC interrupt pins
do this in their pic_enable_intr() routines giving the same behavior as
before. MSI sources do it when the IDT vectors are allocated during
msi_alloc() and msix_alloc().
- Change the intr_table_lock from an sx lock to a mutex.
Tested by: rnoland
- Modules and kernel code alike may use DPCPU_DEFINE(),
DPCPU_GET(), DPCPU_SET(), etc. akin to the statically defined
PCPU_*. Requires only one extra instruction more than PCPU_* and is
virtually the same as __thread for builtin and much faster for shared
objects. DPCPU variables can be initialized when defined.
- Modules are supported by relocating the module's per-cpu linker set
over space reserved in the kernel. Modules may fail to load if there
is insufficient space available.
- Track space available for modules with a one-off extent allocator.
Free may block for memory to allocate space for an extent.
Reviewed by: jhb, rwatson, kan, sam, grehan, marius, marcel, stas
While general idea of patch was good, it was not working properly due the way
it was implemented. When we are using same timer interrupt for several of
hard/prof/stat purposes we should not send several IPIs same time to other
CPUs. Sending several IPIs same time leads to terrible accounting/profiling
results due to strong synchronization effect, when the second interrupt
handler accounts processing of the first one.
Interlink timer events in a such way, that no more then one IPI is sent for
any original timer interrupt.
warning: no time-of-day clock registered, system time will not be set accurately
Provide hints to atrtc on amd64 since it's not being described in
ACPI on some systems.
Reviewed by: jhb
allocated. MSI have strict vectors allocation requirements, which are not
satisfied now during reallocation. This is not the best possible solution,
but better then just broken, as it was.
No objections: current@, arch@, jhb@
memory with 4MB pages was added to pmap_object_init_pt(). This code
assumes that the pages of a OBJT_DEVICE object are always physically
contiguous. Unfortunately, this is not always the case. For example,
jhb@ informs me that the recently introduced /dev/ksyms driver creates
a OBJT_DEVICE object that violates this assumption. Thus, this
revision modifies pmap_object_init_pt() to abort the mapping if the
OBJT_DEVICE object's pages are not physically contiguous. This
revision also changes some inconsistent if not buggy behavior. For
example, the i386 version aborts if the first 4MB virtual page that
would be mapped is already valid. However, it incorrectly replaces
any subsequent 4MB virtual page mappings that it encounters,
potentially leaking a page table page. The amd64 version has a bug of
my own creation. It potentially busies the wrong page and always an
insufficent number of pages if it blocks allocating a page table page.
To my knowledge, there have been no reports of these bugs, hence,
their persistance. I suspect that the existing restrictions that
pmap_object_init_pt() placed on the OBJT_DEVICE objects that it would
choose to map, for example, that the first page must be aligned on a 2
or 4MB physical boundary and that the size of the mapping must be a
multiple of the large page size, were enough to avoid triggering the
bug for drivers like ksyms. However, one side effect of testing the
OBJT_DEVICE object's pages for physical contiguity is that a dubious
difference between pmap_object_init_pt() and the standard path for
mapping devices pages, i.e., vm_fault(), has been eliminated.
Previously, pmap_object_init_pt() would only instantiate the first
PG_FICTITOUS page being mapped because it never examined the rest.
Now, however, pmap_object_init_pt() uses the new function
vm_object_populate() to instantiate them all (in order to support
testing their physical contiguity). These pages need to be
instantiated for the mechanism that I have prototyped for
automatically maintaining the consistency of the PAT settings across
multiple mappings, particularly, amd64's direct mapping, to work.
(Translation: This change is also being made to support jhb@'s work on
the Nvidia feature requests.)
Discussed with: jhb@
In the past there have been some reports of PRINTF_BUFR_SIZE not
functioning correctly. Instead of having garbled console messages, we
should just see whether the issues are still there and analyze them.
Approved by: re
controller. These controllers are also known as L1C(AR8131) and
L2C(AR8132) respectively. These controllers resembles the first
generation controller L1 but usage of different descriptor format
and new register mappings over L1 register space requires a new
driver. There are a couple of registers I still don't understand
but the driver seems to have no critical issues for performance and
stability. Currently alc(4) supports the following hardware
features.
o MSI
o TCP Segmentation offload
o Hardware VLAN tag insertion/stripping
o Tx/Rx interrupt moderation
o Hardware statistics counters(dev.alc.%d.stats)
o Jumbo frame
o WOL
AR8131/AR8132 also supports Tx checksum offloading but I disabled
it due to stability issues. I'm not sure this comes from broken
sample boards or hardware bugs. If you know your controller works
without problems you can still enable it. The controller has a
silicon bug for Rx checksum offloading, so the feature was not
implemented.
I'd like to say big thanks to Atheros. Atheros kindly sent sample
boards to me and answered several questions I had.
HW donated by: Atheros Communications, Inc.
- Interpolate stat/prof clock using clkintr() in a similar fashion to
local APIC timer, since statclock usually run slower.
- Liberate hardclockintr() from taking the burden of handling both stat
and prof clock interrupt. Instead, send IPIs within clkintr() to handle
those.
only during initial booting process, while there are laptops/BIOSes that
tend to act 'smarter' by force enabling C1E if the main power adapter
being pulled out, rendering previous workaround ineffective. Given the
fact that we still rely on local APIC to drive timer interrupt, this
workaround should keep all Turion (probably Phenom too) X\d+ alive whether
its on battery power or not.
URL: http://lists.freebsd.org/pipermail/freebsd-acpi/2008-April/004858.htmlhttp://lists.freebsd.org/pipermail/freebsd-acpi/2008-May/004888.html
Tested by: Peter Jeremy <peterjeremy at optushome d com d au>
It turns out our compiler in stable/7 can't build this code anymore.
Even though my opinion is that those people should just run `make
kernel-toolchain' before building a kernel, I am willing to wait and
commit this after we've branched stable/8.
Requested by: rwatson
Now that we use C99 almost everywhere, just use C99-style in the pmap
code. Since the pmap code is the only consumer of __gnu89_inline, remove
it from cdefs.h as well. Because the flag was only introduced 17 months
ago, I don't expect any problems.
Reviewed by: alc
goal of shipping 8.0 with MAC support in the default kernel. No policies
will be compiled in or enabled by default, but it will now be possible to
load them at boot or runtime without a kernel recompile.
While the framework is not believed to impose measurable overhead when no
policies are loaded (a result of optimization over the past few months in
HEAD), we'll continue to benchmark and optimize as the release approaches.
Please keep an eye out for performance or functionality regressions that
could be a result of this change.
Approved by: re (kensmith)
Obtained from: TrustedBSD Project
The system hostname is now stored in prison0, and the global variable
"hostname" has been removed, as has the hostname_mtx mutex. Jails may
have their own host information, or they may inherit it from the
parent/system. The proper way to read the hostname is via
getcredhostname(), which will copy either the hostname associated with
the passed cred, or the system hostname if you pass NULL. The system
hostname can still be accessed directly (and without locking) at
prison0.pr_host, but that should be avoided where possible.
The "similar information" referred to is domainname, hostid, and
hostuuid, which have also become prison parameters and had their
associated global variables removed.
Approved by: bz (mentor)
machine check code. Disable it by default for now.
- When computing the mask of bits that determines a non-restartable event
during a machine check exception, or-in the overflow flag rather than
replacing the other flags.
PR: i386/134586 [2]
Submitted by: Andi Kleen andi-fbsd firstfloor.org
possible future I-cache coherency operation can succeed. On ARM
for example the L1 cache can be (is) virtually mapped, which
means that any I/O that uses temporary mappings will not see the
I-cache made coherent. On ia64 a similar behaviour has been
observed. By flushing the D-cache, execution of binaries backed
by md(4) and/or NFS work reliably.
For Book-E (powerpc), execution over NFS exhibits SIGILL once in
a while as well, though cpu_flush_dcache() hasn't been implemented
yet.
Doing an explicit D-cache flush as part of the non-DMA based I/O
read operation eliminates the need to do it as part of the
I-cache coherency operation itself and as such avoids pessimizing
the DMA-based I/O read operations for which D-cache are already
flushed/invalidated. It also allows future optimizations whereby
the bcopy() followed by the D-cache flush can be integrated in a
single operation, which could be implemented using on-chips DMA
engines, by-passing the D-cache altogether.
SOCK_NONBLOCK flags, that allow to save fcntl() calls.
Implement a variation of the socket() syscall which takes a flags
in addition to the type argument.
Approved by: kib (mentor)
MFC after: 1 month
- Remove vga0 and the disabled uart2/uart3 hints from both platforms.
- Remove hints for ISA adv0, bt0, aha0, aic0, ed0, cs0, sn0, ie0, fe0, and
le0 from i386. All these hints were marked 'disabled' and thus already
did not work "out of the box".
Discussed with: imp
With the arrival of 128+ cores it is necessary to handle more than that.
One of the first thing to change is the support for cpumask_t that needs
to handle more than 32 bits masking (which happens now). Some places,
however, still assume that cpumask_t is a 32 bits mask.
Fix that situation by using always correctly cpumask_t when needed.
While here, remove the part under STOP_NMI for the Xen support as it
is broken in any case.
Additively make ipi_nmi_pending as static.
Reviewed by: jhb, kmacy
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
- For CPUs that only support MCE (the machine check exception) but not MCA
(i.e. Pentium), all this does is print out the value of the machine check
registers and then panic when a machine check exception occurs.
- For CPUs that support MCA (the machine check architecture), the support is
a bit more involved.
- First, there is limited support for decoding the CPU-independent MCA
error codes in the kernel, and the kernel uses this to output a short
description of any machine check events that occur.
- When a machine check exception occurs, all of the MCx banks on the
current CPU are scanned and any events are reported to the console
before panic'ing.
- To catch events for correctable errors, a periodic timer kicks off a
task which scans the MCx banks on all CPUs. The frequency of these
checks is controlled via the "hw.mca.interval" sysctl.
- Userland can request an immediate scan of the MCx banks by writing
a non-zero value to "hw.mca.force_scan".
- If any correctable events are encountered, the appropriate details
are stored in a 'struct mca_record' (defined in <machine/mca.h>).
The "hw.mca.count" is a count of such records and each record may
be queried via the "hw.mca.records" tree by specifying the record
index (0 .. count - 1) as the next name in the MIB similar to using
PIDs with the kern.proc.* sysctls. The idea is to export machine
check events to userland for more detailed processing.
- The periodic timer and hw.mca sysctls are only present if the CPU
supports MCA.
Discussed with: emaste (briefly)
MFC after: 1 month
introduced in amd64 revision 1.540 and i386 revision 1.547. However, it
had no harmful effects until after a recent change, r189698, on amd64.
(In other words, the error is harmless in RELENG_7.)
The error is triggered by the failure to allocate a pv entry for the one
and only mapping in a page table page. I am addressing the error by
changing pmap_copy() to abort if either pv entry allocation or page
table page allocation fails. This is appropriate because the creation of
mappings by pmap_copy() is optional. They are a (possible) optimization,
and not a requirement.
Correct a nearby whitespace error in the i386 pmap_copy().
Crash reported by: jeff@
MFC after: 6 weeks
to 2.4.0, as it has appeared in the 2.4.0-rc7 first time.
Being exported, AT_CLKTCK is returned by sysconf(_SC_CLK_TCK),
glibc falls back to the hard-coded CLK_TCK value when aux entry
is not present.
Glibc versions prior to 2.2.1 always use hard-coded CLK_TCK value.
For older applications/libc's which depends on hard-coded CLK_TCK
value user should set compat.linux.osrelease less than 2.4.0.
Approved by: kib (mentor)
The frequency of the statistics clock is given by stathz.
Use stathz if it is available, otherwise use hz.
Pointed out by: bde
Approved by: kib (mentor)
OSD-based jail extensions. This allows the Linux MIB to accessed via
jail_set and jail_get, and serves as a demonstration of adding jail support
to a module.
Reviewed by: dchagin, kib
Approved by: bz (mentor)
fix SMP topology detection. On i386, we extend it to cover Core, Core 2,
and Core i7 processors, not just Pentium 4 family, and move it to better
place. On amd64, all supported Intel CPUs should have this MSR.
and hide it inside of atrtc driver. Add new tunable hint.atrtc.0.clock
controlling it. Setting it to 0 disables using RTC clock as stat-/
profclock sources.
Teach i386 and amd64 SMP platforms to emulate stat-/profclocks using i8254
hardclock, when LAPIC and RTC clocks are disabled.
This allows to reduce global interrupt rate of idle system down to about
100 interrupts per core, permitting C3 and deeper C-states provide maximum
CPU power efficiency.
Restore previous behaviour for the case of unknown interrupt. Invocation
of IRQ -1 crashes my system on resume. Returning 0, as it was, is not
perfect also, but at least not so dangerous.
IRQ0 routing on LAPIC-enabled systems.
Add hint.apic.0.clock tunable. Setting it 0 disables using LAPIC timers
as hard-/stat-/profclock sources falling back to using i8254 and rtc timers.
On modern CPUs LAPIC is a part of CPU core which is shutting down when CPU
enters C3 or deeper power state. It makes no problems for interrupt
processing, as chipset wakes up CPU on interrupt triggering. But entering
C3 state kills LAPIC timer and freezes system time, making C3 and deeper
states practically unusable. Using i8254 timer allows to avoid this
problem.
By using i8254 timer my T7700 C2D CPU with UP kernel successfully enters
C3 state, saving more then a Watt of total idle power (>10%) in addition to
all other power-saving techniques.
This technique is not working for SMP yet, as only one CPU receives
timer interrupts. But I think that problem could be fixed by forwarding
interrupts to other CPUs with IPI.
Old implemention used Giant to protect the kernel data structures,
but at the same time called malloc(M_WAITOK), that could cause the
calling thread to sleep and lost Giant protection. User-visible
result was the missed wakeup.
New implementation uses one sx lock per futex. The sx protects
the futex structures and allows to sleep while copyin or copyout
are performed.
Unlike linux, we return EINVAL when FUTEX_CMP_REQUEUE operation
is requested and either caller specified futexes are equial or
second futex already exists. This is acceptable since the situation
can only occur from the application error, and glibc falls back to
old FUTEX_WAKE operation when FUTEX_CMP_REQUEUE returns an error.
Approved by: kib (mentor)
MFC after: 1 month
- Avoid possible divide-by-zero panic on SMP system when the CPUID is
disabled, unsupported, or buggy.
Submitted by: pluknet (pluknet at gmail dot com)[1]
topology of nehalem/corei7 based systems.
- Remove the cpu_cores/cpu_logical detection from identcpu.
- Describe the layout of the system in cpu_mp_announce().
Sponsored by: Nokia
used in some cases):
- Ignore DMA tag boundaries when allocating bounce pages. The boundaries
don't determine whether or not parts of a DMA request bounce. Instead,
they are just used to carve up segments.
- Allow tags with sub-page alignment to share bounce pages since bounce
pages are always page aligned.
Reviewed by: scottl (amd64)
MFC after: 1 month
logical CPUs in a package. We do this by numbering the non-boot CPUs
by starting with the first CPU whose APIC ID is after the boot CPU and
wrapping back around to APIC ID 0 if needed rather than always starting
at APIC ID 0. While here, adjust the cpu_mp_announce() routine to list
CPUs based on the mapping established by assign_cpu_ids() rather than
making assumptions about the algorithm assign_cpu_ids() uses.
MFC after: 1 month
a fair number of static data structures, making this an unlikely
option to try to change without also changing source code. [1]
Change default cache line size on ia64, sparc64, and sun4v to 128
bytes, as this was what rtld-elf was already using on those
platforms. [2]
Suggested by: bde [1], jhb [2]
MFC after: 2 weeks
CACHE_LINE_SIZE constant. These constants are intended to
over-estimate the cache line size, and be used at compile-time
when a run-time tuning alternative isn't appropriate or
available.
Defaults for all architectures are 64 bytes, except powerpc
where it is 128 bytes (used on G5 systems).
MFC after: 2 weeks
Discussed on: arch@
as well as providing stateful load balancing when used with RADIX_MPATH.
- Currently compiled in to i386 and amd64 but disabled by default, it can be enabled at
runtime with 'sysctl net.inet.flowtable.enable=1'.
- Embedded users can remove it entirely from the kernel by adding 'nooption FLOWTABLE' to
their kernel config files.
- A minimal hookup will be added to ip_output in a subsequent commit. I would like to see
more review before bringing in changes that require more churn.
Supported by: Bitgravity Inc.
a tag that has BUS_DMA_KEEP_PG_OFFSET set. Otherwise the page could be
reused with a non-zero offset by a tag that doesn't have
BUS_DMA_KEEP_PG_OFFSET leading to data corruption.
Sleuthing by: avg
Reviewed by: scottl
naming of the partitions (GEOM_PART_EBR_COMPAT). When
compatibility is enabled, changes to the partitioning are
disallowed.
Remove the device name aliasing added previously to provide
backward compatibility, but which in practice doesn't give
us anything.
Enable compatibility on amd64 and i386.
- Do not iterate int 15h, function e820h twice. Instead, we use STAILQ to
store each return buffer and copy all at once.
- Export optional extended attributes defined in ACPI 3.0 as separate
metadata. Currently, there are only two bits defined in the specification.
For example, if the descriptor has extended attributes and it is not
enabled, it has to be ignored by OS. We may implement it in the kernel
later if it is necessary and proven correct in reality.
- Check return buffer size strictly as suggested in ACPI 3.0.
Reviewed by: jhb
Remove a hack to generate more efficient code for port numbers below
0x100, which has been obsolete for at least ten years, because GCC has
an asm constraint to specify that.
Submitted by: Christoph Mallon <christoph mallon gmx de>
