VM_PHYSSEG_SPARSE depending on whether the physical address space is
densely or sparsely populated with memory. The effect of this
definition is to determine which of two implementations of
vm_page_array and PHYS_TO_VM_PAGE() is used. The legacy
implementation is obtained by defining VM_PHYSSEG_DENSE, and a new
implementation that trades off time for space is obtained by defining
VM_PHYSSEG_SPARSE. For now, all architectures except for ia64 and
sparc64 define VM_PHYSSEG_DENSE. Defining VM_PHYSSEG_SPARSE on ia64
allows the entirety of my Itanium 2's memory to be used. Previously,
only the first 1 GB could be used. Defining VM_PHYSSEG_SPARSE on
sparc64 allows USIIIi-based systems to boot without crashing.
This change is a combination of Nathan Whitehorn's patch and my own
work in perforce.
Discussed with: kmacy, marius, Nathan Whitehorn
PR: 112194
- Simplify the amount of work that has be done for each architecture by
pushing more of the truly MI code down into the PCI bus driver.
- Don't bind MSI-X indicies to IRQs so that we can allow a driver to map
multiple MSI-X messages into a single IRQ when handling a message
shortage.
The changes include:
- Add a new pcib_if method: PCIB_MAP_MSI() which is called by the PCI bus
to calculate the address and data values for a given MSI/MSI-X IRQ.
The x86 nexus drivers map this into a call to a new 'msi_map()' function
in msi.c that does the mapping.
- Retire the pcib_if method PCIB_REMAP_MSIX() and remove the 'index'
parameter from PCIB_ALLOC_MSIX(). MD code no longer has any knowledge
of the MSI-X index for a given MSI-X IRQ.
- The PCI bus driver now stores more MSI-X state in a child's ivars.
Specifically, it now stores an array of IRQs (called "message vectors" in
the code) that have associated address and data values, and a small
virtual version of the MSI-X table that specifies the message vector
that a given MSI-X table entry uses. Sparse mappings are permitted in
the virtual table.
- The PCI bus driver now configures the MSI and MSI-X address/data
registers directly via custom bus_setup_intr() and bus_teardown_intr()
methods. pci_setup_intr() invokes PCIB_MAP_MSI() to determine the
address and data values for a given message as needed. The MD code
no longer has to call back down into the PCI bus code to set these
values from the nexus' bus_setup_intr() handler.
- The PCI bus code provides a callout (pci_remap_msi_irq()) that the MD
code can call to force the PCI bus to re-invoke PCIB_MAP_MSI() to get
new values of the address and data fields for a given IRQ. The x86
MSI code uses this when an MSI IRQ is moved to a different CPU, requiring
a new value of the 'address' field.
- The x86 MSI psuedo-driver loses a lot of code, and in fact the separate
MSI/MSI-X pseudo-PICs are collapsed down into a single MSI PIC driver
since the only remaining diff between the two is a substring in a
bootverbose printf.
- The PCI bus driver will now restore MSI-X state (including programming
entries in the MSI-X table) on device resume.
- The interface for pci_remap_msix() has changed. Instead of accepting
indices for the allocated vectors, it accepts a mini-virtual table
(with a new length parameter). This table is an array of u_ints, where
each value specifies which allocated message vector to use for the
corresponding MSI-X message. A vector of 0 forces a message to not
have an associated IRQ. The device may choose to only use some of the
IRQs assigned, in which case the unused IRQs must be at the "end" and
will be released back to the system. This allows a driver to use the
same remap table for different shortage values. For example, if a driver
wants 4 messages, it can use the same remap table (which only uses the
first two messages) for the cases when it only gets 2 or 3 messages and
in the latter case the PCI bus will release the 3rd IRQ back to the
system.
MFC after: 1 month
vm.kmem_size_min. Useful when using ZFS to make sure that vm.kmem size will
be at least 256mb (for example) without forcing a particular value via vm.kmem_size.
Approved by: njl (mentor)
Reviewed by: alc
address ranges used by local and I/O APICs in the system. Some systems
also reserve these ranges as system resources via either PnPBIOS or
ACPI, so this device currently attaches after acpi0 and legacy0 so that
the system resources are given precedence.
variable to avoid invalid constraints in dead code. Use an array of
u_char's (inside a struct) instead of a char/short/int/long variable so
that the variable and its accesses can be spelled in the same way in all
cases and code doesn't need to be cloned just to hold the spelling
differences.
Fixed strict-aliasing errors in PCPU_SET() and in the amd64 PCPU_GET().
Cast to (void *) as in rev.1.37 of the i386 version where the errors
were fixed for the i386 PCPU_GET() only. It would be more correct to
copy to and from the temp. variable using memcpy(), but then an
ifdef tangle would be required to ensure using the builtin memcpy().
We depend on fairly aggressive optimization to put the temp. variable
only in a register despite it being copied using
*(type *)(void *)&anothertype and could depend on this when using
memcpy() too. This seems to work right even for -O0, but the -O0 case
has not been completely tested.
This change gives identical object code for all object files in LINT
on amd64 (except for one file with a __TIME__ stamp). For LINT on
i386 it gives unimportant differences in instruction order and padding
in a few object files. This was only tested for -O.
This change (actually a previous version of it) gives the following
reductions in the number of object files in LINT that fail to compile
with -O2 but without the -fno-strict-aliasing kludge:
- amd64: 29 (down from 211)
- i386: 36 (down from 47)
gcc-3.4.6 actually allows the invalid constraints that result from not
using the temp. variable, at least with -O[1-2], but gcc-3.3.3 crashes
on them and I don't want to depend on compiler bugs.
register takes 16 characters (64-bit register in hex). In practice this
is a slight bit of overkill as 7 of the 56 registers are only 32-bit, but
having the buffer too small results in remote kgdb trashing kernel memory
when it connects.
PR: amd64/108673
Submitted by: Ravi Murty, Nikhil Rao @ Intel
MFC after: 3 days
used by clock code, so don't export it to the world for machdep.c to
initialize. There is a minor problem initializing it before it is
used, since although clock initialization is split up so that parts
of it can be done early, the first part was never done early enough
to actually work. Split it up a bit more and do the first part as
late as possible to document the necessary order. The functions that
implement the split are still bogusly exported.
Cleaned up initialization of the i8254 clock hardware using the new
split. Actually initialize it early enough, and don't work around it
not being initialized in DELAY() when DELAY() is called early for
initialization of some console drivers.
This unfortunately moves a little more code before the early debugger
breakpoint so that it is harder to debug. The ordering of console and
related initialization is delicate because we want to do as little as
possible before the breakpoint, but must initialize a console.
- First off, device drivers really do need to know if they are allocating
MSI or MSI-X messages. MSI requires allocating powerof2() messages for
example where MSI-X does not. To address this, split out the MSI-X
support from pci_msi_count() and pci_alloc_msi() into new driver-visible
functions pci_msix_count() and pci_alloc_msix(). As a result,
pci_msi_count() now just returns a count of the max supported MSI
messages for the device, and pci_alloc_msi() only tries to allocate MSI
messages. To get a count of the max supported MSI-X messages, use
pci_msix_count(). To allocate MSI-X messages, use pci_alloc_msix().
pci_release_msi() still handles both MSI and MSI-X messages, however.
As a result of this change, drivers using the existing API will only
use MSI messages and will no longer try to use MSI-X messages.
- Because MSI-X allows for each message to have its own data and address
values (and thus does not require all of the messages to have their
MD vectors allocated as a group), some devices allow for "sparse" use
of MSI-X message slots. For example, if a device supports 8 messages
but the OS is only able to allocate 2 messages, the device may make the
best use of 2 IRQs if it enables the messages at slots 1 and 4 rather
than default of using the first N slots (or indicies) at 1 and 2. To
support this, add a new pci_remap_msix() function that a driver may call
after a successful pci_alloc_msix() (but before allocating any of the
SYS_RES_IRQ resources) to allow the allocated IRQ resources to be
assigned to different message indices. For example, from the earlier
example, after pci_alloc_msix() returned a value of 2, the driver would
call pci_remap_msix() passing in array of integers { 1, 4 } as the
new message indices to use. The rid's for the SYS_RES_IRQ resources
will always match the message indices. Thus, after the call to
pci_remap_msix() the driver would be able to access the first message
in slot 1 at SYS_RES_IRQ rid 1, and the second message at slot 4 at
SYS_RES_IRQ rid 4. Note that the message slots/indices are 1-based
rather than 0-based so that they will always correspond to the rid
values (SYS_RES_IRQ rid 0 is reserved for the legacy INTx interrupt).
To support this API, a new PCIB_REMAP_MSIX() method was added to the
pcib interface to change the message index for a single IRQ.
Tested by: scottl
MPLOCKED. The cleaning in rev.1.25 was supposed to have been undone
by rev.1.26, but 1.26 could never have actually affected asm files
since atomic.h is full of C declarations so including it in asm files
would just give syntax errors. The asm MPLOCKED is even less needed
than when misplaced definitions of it were first removed, and is now
unused in any asm file in the src tree except in anachronismns in
sys/i386/i386/support.s.
mainly involves removing all __CC_SUPPORTS___INLINE__ ifdefs. These
ifdefs are even less needed for amd64 than for i386, but the i386
atomic.h never had them. The ifdefs here were just an optimization
of obsolescent compatibility cruft (__inline) for a null set of
compilers. I think null sets of compilers should only be supported
in cases where this is more than an optimization, doesn't require
extensive ifdefs, and only involves not-so-obsolescent compatibility
cruft (plain inline here).
These functions are used a lot for mutexes, so this reduces the text
size of an average kernel by about 0.75%. This wasn't intended to
be a significant optimization, but it somehow increased the maximum
number of packets per second that can be transmitted by my bge hardware
from 320000 to 460000 (this benchmark is CPU-bound and remarkably
sensitive to changes in the text section).
Details: we would prefer to leave the result of the cmpxchg in %al,
but cannot tell gcc that it is there, so we have to convert it to an
integer register. We converted to %al, then to %[re]ax, but the
latter step is usually wasted since gcc usually only wants the condition
code and can recover it from %al just as easily as from %[re]ax. Let
gcc promote %al in the few cases where this is needed.
Nearby style fixes;
- let gcc manage the load of `res', and don't abuse `res' for a copy of `exp'
- don't echo `res's name in comments
- consistently spell the condition code as 'e' after comparison for equality
- don't hard-code %al anywhere except in constraints
- for the version that doesn't use cmpxchg, there is no requirement to use
%al anywhere, so don't hard-code it in the constraints either.
Style non-fix:
- for the versions that use cmpxchg, keep using "a" (was %[re]ax, now %al)
for the main output operand, although this is not required. The input
and output operands that use the "a" constraint are now decoupled, and
this makes things clearer except for the reason that the output register
is hard-coded. It is now just a hack to tell gcc that the input "a" has
been clobbered without increasing the number of operands.
as if they were really passed by reference. Specifically, the dead stores
elimination pass in the GCC 4.1 optimiser breaks the non-compliant behavior
on which FreeBSD relied. This change brings FreeBSD up to date by switching
trap frames to being explicitly passed by reference.
Reviewed by: kan
Tested by: kan
of various scattered magic values.
- Pretty print the address of hardware watchpoints in 'show watch' rather
than just displaying hex.
- Expand address field width on amd64 for 64-bit pointers.
- Add a new apic_alloc_vectors() method to the local APIC support code
to allocate N contiguous IDT vectors (aligned on a M >= N boundary).
This function is used to allocate IDT vectors for a group of MSI
messages.
- Add MSI and MSI-X PICs. The PIC code here provides methods to manage
edge-triggered MSI messages as x86 interrupt sources. In addition to
the PIC methods, msi.c also includes methods to allocate and release
MSI and MSI-X messages. For x86, we allow for up to 128 different
MSI IRQs starting at IRQ 256 (IRQs 0-15 are reserved for ISA IRQs,
16-254 for APIC PCI IRQs, and IRQ 255 is reserved).
- Add pcib_(alloc|release)_msi[x]() methods to the MD x86 PCI bridge
drivers to bubble the request up to the nexus driver.
- Add pcib_(alloc|release)_msi[x]() methods to the x86 nexus drivers that
ask the MSI PIC code to allocate resources and IDT vectors.
MFC after: 2 months
of NKPT is no longer enough to run amd64 with 16G of RAM, as it
doesn't have space for mapping a kernel (16M kernel would require
additionally 8 page tables).
- Don't use a frame pointer. Our callers need a frame pointer, but we
could only use one to support things that aren't supported. (These
things are:
- profiling of profiling
- debugging of profiling. The core ENTRY() macro doesn't support
forcing a frame pointer for debugging, so don't do more here.)
- Ensure that we are in the text section and have normal alignment.
- Use the normal syntax for `.type'.
Fixed a syntax error for the (!__KERNEL && !__GNUCLIKE_ASM) case in
rev.1.36. Apparently, this case has never been reached even by lint.
Submitted by: stefanf
{amd64,i386}/include/profile.h:
In case the above case is actually reached, break it properly by
providing null support that will fail at link time instead of a stub
that gives wrong (null) profiling at runtime.
this used to be slightly cleaner than using ifdefs in a few places to
support both a.out and elf, but using it now just causes messes and
unportabilities. It seems to be impossible to implement the elf
HIDENAME() portably in cpp (since token pasting of "." and <name> is
invalid).
*/prof_machdep.c:
- Removed all uses of CNAME(). CNAME() is easy enough to use in pure
asm code, but using it in inline asm requires messy quoting. The
core pure asm code has been hacked on more and all uses of CNAME() in
it have already gone away. Just assume the elf convention here too.
- Removed now-uneeded include of <machine/asmacros.h>.
- Removed the workaround for a namespace conflict with this include.
profiling is configured but high resolution profiling is not configured.
Only functions in *.[Ss] called the stub, so efficiency was not
significantly affected.
(PICs) rather than interrupt sources. This allows interrupt controllers
with no interrupt pics (such as the 8259As when APIC is in use) to
participate in suspend/resume.
- Always register the 8259A PICs even if we don't use any of their pins.
- Explicitly reset the 8259As on resume on amd64 if 'device atpic' isn't
included.
- Add a "dummy" PIC for the local APIC on the BSP to reset the local APIC
on resume. This gets suspend/resume working with APIC on UP systems.
SMP still needs more work to bring the APs back to life.
The MFC after is tentative.
Tested by: anholt (i386)
Submitted by: Andrea Bittau <a.bittau at cs.ucl.ac.uk> (3)
MFC after: 1 week
Submitted by:
Reviewed by:
Approved by:
Obtained from:
MFC after:
Security:
Move the relocation definitions to the common elf header so that DTrace
can use them on one architecture targeted to a different one.
Add the additional ELF types defines in Sun's "Linker and Libraries"
manual.
WB (write-back) on x86 via control bits in PTEs and PDEs (including making
use of the PAT MSR). Changes include:
- A new pmap_mapdev_attr() function for amd64 and i386 which takes an
additional parameter (relative to pmap_mapdev()) specifying the cache
mode for this mapping. Note that on amd64 only WB mappings are done with
the direct map, all other modes result in a private mapping.
- pmap_mapdev() on i386 and amd64 now defaults to using UC (uncached)
mappings rather than WB. Previously we relied on the BIOS setting up
MTRR's to enforce memio regions being treated as UC. This might make
hw.cbb_start_memory unnecessary in some cases now for example.
- A new pmap_mapbios()/pmap_unmapbios() API has been added to allow places
that used pmap_mapdev() to map non-device memory (such as ACPI tables)
to do so using WB as before.
- A new pmap_change_attr() function for amd64 and i386 that changes the
caching mode for a range of KVA.
Reviewed by: alc
Use the method described in IA-32 Intel Architecture Software
Developer's Manual chapter 11.6.6 to get valid mxcsr bits,
use the mxcsr mask to clear invalid bits passed by user code.
via the debug.minidump sysctl and tunable.
Traditional dumps store all physical memory. This was once a good thing
when machines had a maximum of 64M of ram and 1GB of kvm. These days,
machines often have many gigabytes of ram and a smaller amount of kvm.
libkvm+kgdb don't have a way to access physical ram that is not mapped
into kvm at the time of the crash dump, so the extra ram being dumped
is mostly wasted.
Minidumps invert the process. Instead of dumping physical memory in
in order to guarantee that all of kvm's backing is dumped, minidumps
instead dump only memory that is actively mapped into kvm.
amd64 has a direct map region that things like UMA use. Obviously we
cannot dump all of the direct map region because that is effectively
an old style all-physical-memory dump. Instead, introduce a bitmap
and two helper routines (dump_add_page(pa) and dump_drop_page(pa)) that
allow certain critical direct map pages to be included in the dump.
uma_machdep.c's allocator is the intended consumer.
Dumps are a custom format. At the very beginning of the file is a header,
then a copy of the message buffer, then the bitmap of pages present in
the dump, then the final level of the kvm page table trees (2MB mappings
are expanded into a 4K page mappings), then the sparse physical pages
according to the bitmap. libkvm can now conveniently access the kvm
page table entries.
Booting my test 8GB machine, forcing it into ddb and forcing a dump
leads to a 48MB minidump. While this is a best case, I expect minidumps
to be in the 100MB-500MB range. Obviously, never larger than physical
memory of course.
minidumps are on by default. It would want be necessary to turn them off
if it was necessary to debug corrupt kernel page table management as that
would mess up minidumps as well.
Both minidumps and regular dumps are supported on the same machine.
PCB in which the context of stopped CPUs is stored. To access this
PCB from KDB, we introduce a new define, called KDB_STOPPEDPCB. The
definition, when present, lives in <machine/kdb.h> and abstracts
where MD code saves the context. Define KDB_STOPPEDPCB on i386,
amd64, alpha and sparc64 in accordance to previous code.
with large mmap files mapped into many processes, this saves hundreds of
megabytes of ram.
pv entries were individually allocated and had two tailq entries and two
pointers (or addresses). Each pv entry was linked to a vm_page_t and
a process's address space (pmap). It had the virtual address and a
pointer to the pmap.
This change replaces the individual allocation with a per-process
allocation system. A page ("pv chunk") is allocated and this provides
168 pv entries for that process. We can now eliminate one of the 16 byte
tailq entries because we can simply iterate through the pv chunks to find
all the pv entries for a process. We can eliminate one of the 8 byte
pointers because the location of the pv entry implies the containing
pv chunk, which has the pointer. After overheads from the pv chunk
bitmap and tailq linkage, this works out that each pv entry has an
effective size of 24.38 bytes.
Future work still required, and other problems:
* when running low on pv entries or system ram, we may need to defrag
the chunk pages and free any spares. The stats (vm.pmap.*) show that
this doesn't seem to be that much of a problem, but it can be done if
needed.
* running low on pv entries is now a much bigger problem. The old
get_pv_entry() routine just needed to reclaim one other pv entry.
Now, since they are per-process, we can only use pv entries that are
assigned to our current process, or by stealing an entire page worth
from another process. Under normal circumstances, the pmap_collect()
code should be able to dislodge some pv entries from the current
process. But if needed, it can still reclaim entire pv chunk pages
from other processes.
* This should port to i386 really easily, except there it would reduce
pv entries from 24 bytes to about 12 bytes.
(I have integrated Alan's recent changes.)
- Throw out all of the logical APIC ID stuff. The Intel docs are somewhat
ambiguous, but it seems that the "flat" cluster model we are currently
using is only supported on Pentium and P6 family CPUs. The other
"hierarchy" cluster model that is supported on all Intel CPUs with
local APICs is severely underdocumented. For example, it's not clear
if the OS needs to glean the topology of the APIC hierarchy from
somewhere (neither ACPI nor MP Table include it) and setup the logical
clusters based on the physical hierarchy or not. Not only that, but on
certain Intel chipsets, even though there were 4 CPUs in a logical
cluster, all the interrupts were only sent to one CPU anyway.
- We now bind interrupts to individual CPUs using physical addressing via
the local APIC IDs. This code has also moved out of the ioapic PIC
driver and into the common interrupt source code so that it can be
shared with MSI interrupt sources since MSI is addressed to APICs the
same way that I/O APIC pins are.
- Interrupt source classes grow a new method pic_assign_cpu() to bind an
interrupt source to a specific local APIC ID.
- The SMP code now tells the interrupt code which CPUs are avaiable to
handle interrupts in a simpler and more intuitive manner. For one thing,
it means we could now choose to not route interrupts to HT cores if we
wanted to (this code is currently in place in fact, but under an #if 0
for now).
- For now we simply do static round-robin of IRQs to CPUs when the first
interrupt handler just as before, with the change that IRQs are now
bound to individual CPUs rather than groups of up to 4 CPUs.
- Because the IRQ to CPU mapping has now been moved up a layer, it would
be easier to manage this mapping from higher levels. For example, we
could allow drivers to specify a CPU affinity map for their interrupts,
or we could allow a userland tool to bind IRQs to specific CPUs.
The MFC is tentative, but I want to see if this fixes problems some folks
had with UP APIC kernels on 6.0 on SMP machines (an SMP kernel would work
fine, but a UP APIC kernel (such as GENERIC in RELENG_6) would lose
interrupts).
MFC after: 1 week
param.h. Per request, I've placed these just after the
_NO_NAMESPACE_POLLUTION ifndef. I've not renamed anything yet, but
may since we don't need the __.
Submitted by: bde, jhb, scottl, many others.
passing a pointer to an opaque clockframe structure and requiring the
MD code to supply CLKF_FOO() macros to extract needed values out of the
opaque structure, just pass the needed values directly. In practice this
means passing the pair (usermode, pc) to hardclock() and profclock() and
passing the boolean (usermode) to hardclock_cpu() and hardclock_process().
Other details:
- Axe clockframe and CLKF_FOO() macros on all architectures. Basically,
all the archs were taking a trapframe and converting it into a clockframe
one way or another. Now they can just extract the PC and usermode values
directly out of the trapframe and pass it to fooclock().
- Renamed hardclock_process() to hardclock_cpu() as the latter is more
accurate.
- On Alpha, we now run profclock() at hz (profhz == hz) rather than at
the slower stathz.
- On Alpha, for the TurboLaser machines that don't have an 8254
timecounter, call hardclock() directly. This removes an extra
conditional check from every clock interrupt on Alpha on the BSP.
There is probably room for even further pruning here by changing Alpha
to use the simplified timecounter we use on x86 with the lapic timer
since we don't get interrupts from the 8254 on Alpha anyway.
- On x86, clkintr() shouldn't ever be called now unless using_lapic_timer
is false, so add a KASSERT() to that affect and remove a condition
to slightly optimize the non-lapic case.
- Change prototypeof arm_handler_execute() so that it's first arg is a
trapframe pointer rather than a void pointer for clarity.
- Use KCOUNT macro in profclock() to lookup the kernel profiling bucket.
Tested on: alpha, amd64, arm, i386, ia64, sparc64
Reviewed by: bde (mostly)
- Move PUSH_FRAME and POP_FRAME to asmacros.h and use PUSH_FRAME in
atpic entry points.
- Move PCPU_* asm macros out of the middle of the asm profiling macros.
- Pass IRQ vector argument as an int rather than void * to reduce diffs
with i386.
- EOI the lapic in C for the lapic timer handler.
- GC unused Xcpuast function.
- Split IPI_STOP handling code of ipi_nmi_handler() out into a
cpustop_handler() function and call it from Xcpustop rather than
duplicating all the logic in assembly.
- Fixup the list of symbols with interrupt frames in ddb traces.
Xatpic_fastintr* have never existed on amd64, and the lapic timer
handler and various IPI handlers were missing.
- Use trapframe instead of intrframe for interrupt entry points (on amd64
the interrupt vector was already a separate argument, so the two frames
were already identical) and GC intrframe.
Submitted by: peter (3)
- Move vtophys() macros next to vtopte() where vtopte() exists to match
comments above vtopte().
- Remove references to the alternate address space in the comment above
vtopte(). amd64 never had the alternate address space, and i386 lost it
prior to PAE support being added.
- s/entires/entries/ in comments.
Reviewed by: alc
MACHINE_ARCH and MACHINE). Their purpose was to be able to test
in cpp(1), but cpp(1) only understands integer type expressions.
Using such unsupported expressions introduced a number of subtle
bugs, which were discovered by compiling with -Wundef.
source is first enabled similar to how intr_event's now allocate ithreads
on-demand. Previously, we would map IDT vectors 1:1 to IRQs. Since we
only have 191 available IDT vectors for I/O interrupts, this limited us
to only supporting IRQs 0-190 corresponding to the first 190 I/O APIC
intpins. On many machines, however, each PCI-X bus has its own APIC even
though it only has 1 or 2 devices, thus, we were reserving between 24 and
32 IRQs just for 1 or 2 devices and thus 24 or 32 IDT vectors. With this
change, a machine with 100 IRQs but only 5 in use will only use up 5 IDT
vectors. Also, this change provides an API (apic_alloc_vector() and
apic_free_vector()) that will allow a future MSI interrupt source driver to
request IDT vectors for use by MSI interrupts on x86 machines.
Tested on: amd64, i386
and increase flexibility to allow various different approaches to be tried
in the future.
- Split struct ithd up into two pieces. struct intr_event holds the list
of interrupt handlers associated with interrupt sources.
struct intr_thread contains the data relative to an interrupt thread.
Currently we still provide a 1:1 relationship of events to threads
with the exception that events only have an associated thread if there
is at least one threaded interrupt handler attached to the event. This
means that on x86 we no longer have 4 bazillion interrupt threads with
no handlers. It also means that interrupt events with only INTR_FAST
handlers no longer have an associated thread either.
- Renamed struct intrhand to struct intr_handler to follow the struct
intr_foo naming convention. This did require renaming the powerpc
MD struct intr_handler to struct ppc_intr_handler.
- INTR_FAST no longer implies INTR_EXCL on all architectures except for
powerpc. This means that multiple INTR_FAST handlers can attach to the
same interrupt and that INTR_FAST and non-INTR_FAST handlers can attach
to the same interrupt. Sharing INTR_FAST handlers may not always be
desirable, but having sio(4) and uhci(4) fight over an IRQ isn't fun
either. Drivers can always still use INTR_EXCL to ask for an interrupt
exclusively. The way this sharing works is that when an interrupt
comes in, all the INTR_FAST handlers are executed first, and if any
threaded handlers exist, the interrupt thread is scheduled afterwards.
This type of layout also makes it possible to investigate using interrupt
filters ala OS X where the filter determines whether or not its companion
threaded handler should run.
- Aside from the INTR_FAST changes above, the impact on MD interrupt code
is mostly just 's/ithread/intr_event/'.
- A new MI ddb command 'show intrs' walks the list of interrupt events
dumping their state. It also has a '/v' verbose switch which dumps
info about all of the handlers attached to each event.
- We currently don't destroy an interrupt thread when the last threaded
handler is removed because it would suck for things like ppbus(8)'s
braindead behavior. The code is present, though, it is just under
#if 0 for now.
- Move the code to actually execute the threaded handlers for an interrrupt
event into a separate function so that ithread_loop() becomes more
readable. Previously this code was all in the middle of ithread_loop()
and indented halfway across the screen.
- Made struct intr_thread private to kern_intr.c and replaced td_ithd
with a thread private flag TDP_ITHREAD.
- In statclock, check curthread against idlethread directly rather than
curthread's proc against idlethread's proc. (Not really related to intr
changes)
Tested on: alpha, amd64, i386, sparc64
Tested on: arm, ia64 (older version of patch by cognet and marcel)
IPI_STOP IPIs.
- Change the i386 and amd64 MD IPI code to send an NMI if STOP_NMI is
enabled if an attempt is made to send an IPI_STOP IPI. If the kernel
option is enabled, there is also a sysctl to change the behavior at
runtime (debug.stop_cpus_with_nmi which defaults to enabled). This
includes removing stop_cpus_nmi() and making ipi_nmi_selected() a
private function for i386 and amd64.
- Fix ipi_all(), ipi_all_but_self(), and ipi_self() on i386 and amd64 to
properly handle bitmapped IPIs as well as IPI_STOP IPIs when STOP_NMI is
enabled.
- Fix ipi_nmi_handler() to execute the restart function on the first CPU
that is restarted making use of atomic_readandclear() rather than
assuming that the BSP is always included in the set of restarted CPUs.
Also, the NMI handler didn't clear the function pointer meaning that
subsequent stop and restarts could execute the function again.
- Define a new macro HAVE_STOPPEDPCBS on i386 and amd64 to control the use
of stoppedpcbs[] and always enable it for i386 and amd64 instead of
being dependent on KDB_STOP_NMI. It works fine in both the NMI and
non-NMI cases.
- Add newer CPUID definitions for future use.
Many thanks to Mike Tancsa <mike at sentex dot net> for providing test
cases for Intel Pentium D and AMD Athlon 64 X2.
Approved by: anholt (mentor)
variable and returns the previous value of the variable.
Tested on: i386, alpha, sparc64, arm (cognet)
Reviewed by: arch@
Submitted by: cognet (arm)
MFC after: 1 week
constraint is actually only allowed for register operands. Instead, use
separate input and output memory constraints.
Education from: alc
Reviewed by: alc
Tested on: i386, alpha
MFC after: 1 week
it to __MINSIGSTKSZ. Define MINSIGSTKSZ in <sys/signal.h>.
This is done in order to use MINSIGSTKSZ for the macro PTHREAD_STACK_MIN
in <pthread.h> (soon <limits.h>) without having to include the whole
<sys/signal.h> header.
Discussed with: bde
and return a printable representation.
This fixes recognition of the PC Engines WRAP and improves the
recognition of the Soekris boards (Bios version can now be
seen in the dmesg output for instance).
Also, add watchdog support for PCM-582x platforms.
Submitted by: Adrian Steinmann <ast@marabu.ch>
Slightly changed by: phk
PR: 81360
variables rather than void * variables. This makes it easier and simpler
to get asm constraints and volatile keywords correct.
MFC after: 3 days
Tested on: i386, alpha, sparc64
Compiled on: ia64, powerpc, amd64
Kernel toolchain busted on: arm
further changes and fixes in the future:
- Use aliases via macros rather than duplicated inlines wherever possible.
- Move all the aliases to the bottom of these files and the inline
functions to the top.
- Add various comments.
- On alpha, drop atomic_{load_acq,store_rel}_{8,char,16,short}().
- On i386 and amd64, don't duplicate the extern declarations for functions
in the two non-inline cases (KLD_MODULE and compiler doesn't do inlines),
instead, consolidate those two cases.
- Some whitespace fixes.
Approved by: re (scottl)
packet filter. This would cause a panic on architectures that require strict
alignment such as sparc64 (tier1) and ia64/ppc (tier2).
This adds two new macros that check the alignment, these are compile time
dependent on __NO_STRICT_ALIGNMENT which is set for i386 and amd64 where
alignment isn't need so the cost is avoided.
IP_HDR_ALIGNED_P()
IP6_HDR_ALIGNED_P()
Move bridge_ip_checkbasic()/bridge_ip6_checkbasic() up so that the alignment
is checked for ipfw and dummynet too.
PR: ia64/81284
Obtained from: NetBSD
Approved by: re (dwhite), mlaier (mentor)
dump format. The key reason to do this is so that we can dump sparse
address space. For example, we need to be able to skip the PCI hole
just below the 4GB boundary. Trying to destructively dump MMIO device
registers is Really Bad(TM). The frequent result of trying to do a
crash dump on a machine with 4GB or more ram was ugly (lockup or reboot).
This code has been taken directly from the IA64 dump_machdep.c code,
with just a few (mostly minor) mods.
Introduce a dump_avail[] array in the machdep.c code so that we have a
source of truth for what memory is present in a machine that needs to be
dumped. We can't use phys_avail[] because all sorts of things slice
memory out of it that we really need to dump. eg: the vm page array
and the dmesg buffer. dump_avail[] is pretty much an unmolested version
of phys_avail[]. It does have Maxmem correction.
Bump the i386 and amd64 dump format to version 2, but nothing actually
uses this. amd64 was actually using the i386 dump version number.
libkvm support to follow.
Approved by: re
- Implement sampling modes and logging support in hwpmc(4).
- Separate MI and MD parts of hwpmc(4) and allow sharing of
PMC implementations across different architectures.
Add support for P4 (EMT64) style PMCs to the amd64 code.
- New pmcstat(8) options: -E (exit time counts) -W (counts
every context switch), -R (print log file).
- pmc(3) API changes, improve our ability to keep ABI compatibility
in the future. Add more 'alias' names for commonly used events.
- bug fixes & documentation.
i8253reg.h, and add some defines to control a speaker.
- Move PPI related defines from i386/isa/spkr.c into ppireg.h and use them.
- Move IO_{PPI,TIMER} defines into ppireg.h and timerreg.h respectively.
- Use isa/isareg.h rather than <arch>/isa/isa.h.
Tested on: i386, pc98
a regular IPI vector, but this vector is blocked when interrupts are disabled.
With "options KDB_STOP_NMI" and debug.kdb.stop_cpus_with_nmi set, KDB will
send an NMI to each CPU instead. The code also has a context-stuffing
feature which helps ddb extract the state of processes running on the
stopped CPUs.
KDB_STOP_NMI is only useful with SMP and complains if SMP is not defined.
This feature only applies to i386 and amd64 at the moment, but could be
used on other architectures with the appropriate MD bits.
Submitted by: ups
inclusion of <sys/pmc.h> and depending on being included from
that header file.
o Include any MD specific header files that otherwise need to be
included from MI files.
Ok'd: jkoshy@
into _bus.h to help with name space polution from including all of bus.h.
In a few days, I'll commit changes to the MI code to take advantage of thse
sepration (after I've made sure that these changes don't break anything in
the main tree, I've tested in my trees, but you never know...).
Suggested by: bde (in 2002 or 2003 I think)
Reviewed in principle by: jhb
critical_enter() and critical_exit() are now solely a mechanism for
deferring kernel preemptions. They no longer have any affect on
interrupts. This means that standalone critical sections are now very
cheap as they are simply unlocked integer increments and decrements for the
common case.
Spin mutexes now use a separate KPI implemented in MD code: spinlock_enter()
and spinlock_exit(). This KPI is responsible for providing whatever MD
guarantees are needed to ensure that a thread holding a spin lock won't
be preempted by any other code that will try to lock the same lock. For
now all archs continue to block interrupts in a "spinlock section" as they
did formerly in all critical sections. Note that I've also taken this
opportunity to push a few things into MD code rather than MI. For example,
critical_fork_exit() no longer exists. Instead, MD code ensures that new
threads have the correct state when they are created. Also, we no longer
try to fixup the idlethreads for APs in MI code. Instead, each arch sets
the initial curthread and adjusts the state of the idle thread it borrows
in order to perform the initial context switch.
This change is largely a big NOP, but the cleaner separation it provides
will allow for more efficient alternative locking schemes in other parts
of the kernel (bare critical sections rather than per-CPU spin mutexes
for per-CPU data for example).
Reviewed by: grehan, cognet, arch@, others
Tested on: i386, alpha, sparc64, powerpc, arm, possibly more
compiler features tests. This is ok, since machine/ieeefp.h is an internal
interface. But floatingpoint.h is a public interface and some ports use it,
so include sys/cdefs.h in the amd64 and i386 version of floatingpoint.h.
Note: some architectures don't provide recursive inclusion protection in
floatingpoint.h, namely alpha and ia64. Except for this part and now the
include of sys/cdefs.h, all those files are equal (from a compiler POV),
so they could be moved to only one version in src/include/.
Approved by: joerg
to mistakes from day 1, it has always had semantics inconsistent with
SVR4 and its successors. In particular, given argument M:
- On Solaris and FreeBSD/{alpha,sparc64}, it clobbers the old flags
and *sets* the new flag word to M. (NetBSD, too?)
- On FreeBSD/{amd64,i386}, it *clears* the flags that are specified in M
and leaves the remaining flags unchanged (modulo a small bug on amd64.)
- On FreeBSD/ia64, it is not implemented.
There is no way to fix fpsetsticky() to DTRT for both old FreeBSD apps
and apps ported from other operating systems, so the best approach
seems to be to kill the function and fix any apps that break. I
couldn't find any ports that use it, and any such ports would already
be broken on FreeBSD/ia64 and Linux anyway.
By the way, the routine has always been undocumented in FreeBSD,
except for an MLINK to a manpage that doesn't describe it. This
manpage has stated since 5.3-RELEASE that the functions it describes
are deprecated, so that must mean that functions that it is *supposed*
to describe but doesn't are even *more* deprecated. ;-)
Note that fpresetsticky() has been retained on FreeBSD/i386. As far
as I can tell, no other operating systems or ports of FreeBSD
implement it, so there's nothing for it to be inconsistent with.
PR: 75862
Suggested by: bde
sys/bus_dma.h instead of being copied in every single arch. This slightly
reorders a flag that was specific to AXP and thus changes the ABI there.
The interface still relies on bus_space definitions found in <machine/bus.h>
so it cannot be included on its own yet, but that will be fixed at a later
date. Add an MD <machine/bus_dma.h> for ever arch for consistency and to
allow for future MD augmentation of the API. sparc64 makes heavy use of
this right now due to its different bus_dma implemenation.
place.
This moves the dependency on GCC's and other compiler's features into
the central sys/cdefs.h file, while the individual source files can
then refer to #ifdef __COMPILER_FEATURE_FOO where they by now used to
refer to #if __GNUC__ > 3.1415 && __BARC__ <= 42.
By now, GCC and ICC (the Intel compiler) have been actively tested on
IA32 platforms by netchild. Extension to other compilers is supposed
to be possible, of course.
Submitted by: netchild
Reviewed by: various developers on arch@, some time ago
cuts to the chase and fills in a provided s/g list. This is meant to optimize
out the cost of the callback since the callback doesn't serve much purpose for
mbufs since mbuf loads will never be deferred. This is just for amd64 and
i386 at the moment, other arches will be coming shortly.
specified register, but a pointer to the in-memory representation of
that value. The reason for this is twofold:
1. Not all registers can be represented by a register_t. In particular
FP registers fall in that category. Passing the new register value
by reference instead of by value makes this point moot.
2. When we receive a G or P packet, both are for writing a register,
the packet will have the register value in target-byte order and
in the memory representation (modulo the fact that bytes are sent
as 2 printable hexadecimal numbers of course). We only need to
decode the packet to have a pointer to the register value.
This change fixes the bug of extracting the register value of the P
packet as a hexadecimal number instead of as a bit array. The quick
(and dirty) fix to bswap the register value in gdb_cpu_setreg() as
it has been added on i386 and amd64 can therefore be removed and has
in fact been that.
Tested on: alpha, amd64, i386, ia64, sparc64
that was greater than 4G. I originally used the same values as i386 in
order to save opening a new PML4 page slot, but in the day of gigabytes
of memory, worrying about a 4K page seems futile. Moving from 8 to 32G
moves the page to a different index, it doesn't increase the number of
pages used.
Restructure pmap_enter() to prevent the loss of a page modified (PG_M) bit
in a race between processors. (This restructuring assumes the newly atomic
pte_load_store() for correct operation.)
Reviewed by: tegge@
PR: i386/61852
pmap_copy(). This entails additional locking in pmap_copy() and the
addition of a "flags" parameter to the page table page allocator for
specifying whether it may sleep when memory is unavailable. (Already,
pmap_copy() checks the availability of memory, aborting if it is scarce.
In theory, another CPU could, however, allocate memory between
pmap_copy()'s check and the call to the page table page allocator,
causing the current thread to release its locks and sleep. This change
makes this scenario impossible.)
Reviewed by: tegge@
value was only enough for 8GB of RAM, the new value can do 16GB. This still
isn't optimal since it doesn't scale. Fixing this for amd64 looks to be
fairly easy, but for i386 will be quite difficult.
Reviewed by: peter
FULL_PREEMPTION is defined. Add a runtime warning to ULE if PREEMPTION is
enabled (code inspired by the PREEMPTION warning in kern_switch.c). This
is a possible MT5 candidate.
these two reasons:
1. On ia64 a function pointer does not hold the address of the first
instruction of a functions implementation. It holds the address
of a function descriptor. Hence the user(), btrap(), eintr() and
bintr() prototypes are wrong for getting the actual code address.
2. The logic forces interrupt, trap and exception entry points to
be layed-out contiguously. This can not be achieved on ia64 and is
generally just bad programming.
The MCOUNT_FROMPC_USER macro is used to set the frompc argument to
some kernel address which represents any frompc that falls outside
the kernel text range. The macro can expand to ~0U to bail out in
that case.
The MCOUNT_FROMPC_INTR macro is used to set the frompc argument to
some kernel address to represent a call to a trap or interrupt
handler. This to avoid that the trap or interrupt handler appear to
be called from everywhere in the call graph. The macro can expand
to ~0U to prevent adjusting frompc. Note that the argument is selfpc,
not frompc.
This commit defines the macros on all architectures equivalently to
the original code in sys/libkern/mcount.c. People can take it from
here...
Compile-tested on: alpha, amd64, i386, ia64 and sparc64
Boot-tested on: i386
logical CPUs on a system to be used as a dedicated watchdog to cause a
drop to the debugger and/or generate an NMI to the boot processor if
the kernel ceases to respond. A sysctl enables the watchdog running
out of the processor's idle thread; a callout is launched to reset a
timer in the watchdog. If the callout fails to reset the timer for ten
seconds, the watchdog will fire. The sysctl allows you to select which
CPU will run the watchdog.
A sample "debug.leak_schedlock" is included, which causes a sysctl to
spin holding sched_lock in order to trigger the watchdog. On my Xeons,
the watchdog is able to detect this failure mode and break into the
debugger, which cannot otherwise be done without an NMI button.
This option does not currently work with sched_ule due to ule's push
notion of scheduling, similar to machdep.hlt_logical_cpus failing to
work with that scheduler.
On face value, this might seem somewhat inefficient, but there are a
lot of dual-processor Xeons with HTT around, so using one as a watchdog
for testing is not as inefficient as one might fear.
being defined, define and use a new MD macro, cpu_spinwait(). It only
expands to something on i386 and amd64, so the compiled code should be
identical.
Name of the macro found by: jhb
Reviewed by: jhb
their own directory and module, leaving the MD parts in the MD
area (the MD parts _are_ part of the modules). /dev/mem and /dev/io
are now loadable modules, thus taking us one step further towards
a kernel created entirely out of modules. Of course, there is nothing
preventing the kernel from having these statically compiled.
dereference curthread. It is called only from critical_{enter,exit}(),
which already dereferences curthread. This doesn't seem to affect SMP
performance in my benchmarks, but improves MySQL transaction throughput
by about 1% on UP on my Xeon.
Head nodding: jhb, bmilekic
reduces the size of the pv_entry structure a small but significant amount.
This is implemented a little differently because it isn't so cheap to get
the physical address of the page tabke page on amd64.. instead of it
being directly accessible from the top level page directory, it is now
two additional tree levels down. However.. In almost all cases, we
recently had the physical address if the page table page a short while
before we needed it, but it slipped through our fingers. This patch
saves it for when we do need it. Also, for the one case where we do not
have the ptp paddr, we are always running in curproc context and so we
can do a vtopte-like trick. I've implemented vtopde() for this purpose.
There is still a CYA entry in pmap_unuse_pt() that needs to be removed. I
think it can be removed now but I forgot to test with it gone.
Most of the changes are a direct result of adding thread awareness.
Typically, DDB_REGS is gone. All registers are taken from the
trapframe and backtraces use the PCB based contexts. DDB_REGS was
defined to be a trapframe on all platforms anyway.
Thread awareness introduces the following new commands:
thread X switch to thread X (where X is the TID),
show threads list all threads.
The backtrace code has been made more flexible so that one can
create backtraces for any thread by giving the thread ID as an
argument to trace.
With this change, ia64 has support for breakpoints.
a PCB from a trapframe for purposes of unwinding the stack. The PCB
is used as the thread context and all but the thread that entered the
debugger has a valid PCB.
This function can also be used to create a context for the threads
running on the CPUs that have been stopped when the debugger got
entered. This however is not done at the time of this commit.
in which multiple (presumably different) debugger backends can be
configured and which provides basic services to those backends.
Besides providing services to backends, it also serves as the single
point of contact for any and all code that wants to make use of the
debugger functions, such as entering the debugger or handling of the
alternate break sequence. For this purpose, the frontend has been
made non-optional.
All debugger requests are forwarded or handed over to the current
backend, if applicable. Selection of the current backend is done by
the debug.kdb.current sysctl. A list of configured backends can be
obtained with the debug.kdb.available sysctl. One can enter the
debugger by writing to the debug.kdb.enter sysctl.
backend improves over the old GDB support in the following ways:
o Unified implementation with minimal MD code.
o A simple interface for devices to register themselves as debug
ports, ala consoles.
o Compression by using run-length encoding.
o Implements GDB threading support.
than as one-off hacks in various other parts of the kernel:
- Add a function maybe_preempt() that is called from sched_add() to
determine if a thread about to be added to a run queue should be
preempted to directly. If it is not safe to preempt or if the new
thread does not have a high enough priority, then the function returns
false and sched_add() adds the thread to the run queue. If the thread
should be preempted to but the current thread is in a nested critical
section, then the flag TDF_OWEPREEMPT is set and the thread is added
to the run queue. Otherwise, mi_switch() is called immediately and the
thread is never added to the run queue since it is switch to directly.
When exiting an outermost critical section, if TDF_OWEPREEMPT is set,
then clear it and call mi_switch() to perform the deferred preemption.
- Remove explicit preemption from ithread_schedule() as calling
setrunqueue() now does all the correct work. This also removes the
do_switch argument from ithread_schedule().
- Do not use the manual preemption code in mtx_unlock if the architecture
supports native preemption.
- Don't call mi_switch() in a loop during shutdown to give ithreads a
chance to run if the architecture supports native preemption since
the ithreads will just preempt DELAY().
- Don't call mi_switch() from the page zeroing idle thread for
architectures that support native preemption as it is unnecessary.
- Native preemption is enabled on the same archs that supported ithread
preemption, namely alpha, i386, and amd64.
This change should largely be a NOP for the default case as committed
except that we will do fewer context switches in a few cases and will
avoid the run queues completely when preempting.
Approved by: scottl (with his re@ hat)
present and thus that the PnPBIOS probe should be skipped instead of
having ACPI zero out the PnPBIOStable pointer.
- Make the PnPBIOStable pointer static to i386/i386/bios.c now that that is
the only place it is used.
- export the rest of the cpu features (and amd's features).
- turn on EFER_NXE, depending on the NX amd feature bit
- reorg the identcpu stuff a bit in order to stop treating the
amd features as second class features (since it is now a primary feature
bit set) and make it easier to export.
lives in the top 12 'available' bits. atop() in the PHYS_TO_VM_PAGE()
macro only masks off the lower bits (by accident) and the upper bits
in the 64 bit ptes turn into "interesting" index values.
to <sys/gmon.h>. Cleaned them up a little by not attempting to ifdef
for incomplete and out of date support for GUPROF in userland, as in
the sparc64 version.
different context support for 32 vs 64 bit processes. This simply omits
the save/restore of the segment selector registers for non 32 bit
processes. This avoids the rdmsr/rwmsr juggling when restoring %gs
clobbers the kernel msr that holds the gsbase.
However, I suspect it might be better to conditionally do this at
user<->kernel transition where we wouldn't need to do the juggling in the
first place. Or have per-thread extended context save/restore hooks.
to help the AMD cpus (which have a hardware tlb flush filter). I held
off to see what the 64 bit Intel cpus did, but it doesn't seem to help
much there either. Oh well, store it in the Attic.
individual asm versions. The global lock is shared between the BIOS and
OS and thus cannot use our mutexes. It is defined in section 5.2.9.1 of
the ACPI specification.
Reviewed by: marcel, bde, jhb
move its declaration to the machine-dependent header file on those
machines that use it. In principle, only i386 should have it.
Alpha and AMD64 should use their direct virtual-to-physical mapping.
- Remove pmap_kenter_temporary() from ia64. It is unused. Approved
by: marcel@
level of abstraction for any and all CPU mask and CPU bitmap variables
so that platforms have the ability to break free from the hard limit
of 32 CPUs, simply because we don't have more bits in an u_int. Note
that the type is not supposed to solve massive parallelism, where
the number of CPUs can be larger than the width of the widest integral
type. As such, cpumask_t is not supposed to be a compound type. If
such would be necessary in the future, we can deal with the issues
then and there. For now, it can be assumed that the type is integral
and unsigned.
With this commit, all MD definitions start off as u_int. This allows
us to phase-in cpumask_t at our leasure without breaking anything.
Once cpumask_t is used consistently, platforms can switch to wider
(or smaller) types if such would be beneficial (or not; whatever :-)
Compile-tested on: i386
in the non-_KERNEL case. This "fixes" applications that include
this "kernel-only" header and also include <strings.h> (or get
<strings.h> via the default _BSD_VISIBLE pollution in <string.h>.
In C++ there was a fatal error: the declaration specifies C linkage
but the implementation gives C++ linkage. In C there was only a
static/extern mismatch if the headers were included in a certain order
order, and a partially redundant declaration for all include orders;
gcc emits incomplete or wrong diagnostics for these, but only for
compiling with -Wsystem-headers and certain other warning options, so
the problem was usually not seen for C.
Ports breakage reported by: kris