sockets into machine-dependent files. The rationale for this
migration is illustrated by the modified amd64 allocator. It uses the
amd64's direct map to avoid emphemeral mappings in the kernel's
address space. On an SMP, the emphemeral mappings result in an IPI
for TLB shootdown for each transmitted page. Yuck.
Maintainers of other 64-bit platforms with direct maps should be able
to use the amd64 allocator as a reference implementation.
change also disables interrupts around non-S4 suspends whereas before we
did not do this. Our version of AcpiEnterSleepStateS4bios was almost
identical to the ACPICA version.
- Add a new PCIM_HDRTYPE constant for the field in PCIR_HDRTYPE that holds
the header type.
- Replace several magic numbers with appropriate constants for the header
type register and a couple of PCI_FUNCMAX.
- Merge to amd64 the fix to the i386 bridge code to skip devices with
unknown header types.
Requested by: imp (1, 2)
_pmap_allocpte(): Guarantee that the page table page is zero filled before
adding it to the directory. Otherwise, a 2nd, 3rd, etc. thread could
access a nearby virtual address and use garbage for the address
translation.
Discussed with: peter, tegge
prototypes of cpu_halt(), cpu_reset() and swi_vm() from md_var.h to
cpu.h. This affects db_command.c and kern_shutdown.c.
ia64: move all MD prototypes from cpu.h to md_var.h. This affects
madt.c, interrupt.c and mp_machdep.c. Remove is_physical_memory().
It's not used (vm_machdep.c).
alpha: the MD prototypes have been left in cpu.h with a comment
that they should be there. Moving them is left for later. It was
expected that the impact would be significant enough to be done in
a seperate commit.
powerpc: MD prototypes left in cpu.h. Comment added.
Suggested by: bde
Tested with: make universe (pc98 incomplete)
A timecounter will be selected when registered if its quality is
not negative and no less than the current timecounters.
Add a sysctl to report all available timecounters and their qualities.
Give the dummy timecounter a solid negative quality of minus a million.
Give the i8254 zero and the ACPI 1000.
The TSC gets 800, unless APM or SMP forces it negative.
Other timecounters default to zero quality and thereby retain current
selection behaviour.
- Add a macro for the logical shift needed to extract an APIC ID from
either from the local APIC ICR Hi register or the APIC ID registers of
the local and IO APICs.
was masked. However KIMURA Yasuhiro-san noticed my mistake and was
kind enough to provide a better patch in PR 55581. I've merged that
into the routine. Hopefully I've not overlooked anything this time.
MFC After: 5 days
ioctls.
In the particular case of ptrace(), this commit more-or-less reverts
revision 1.53 of sys_process.c, which appears to have been erroneous.
Reviewed by: iedowse, jhb
parameter. The new name better reflects what the function does and
how it is used. The last parameter was always FALSE.
Note: In theory, gcc would perform constant propagation and dead code
elimination to achieve the same effect as removing the last parameter,
which is always FALSE. In practice, recent versions do not. So, there
is little point in letting unused code pessimize execution.
queues lock such that it isn't held around the call to get_pv_entry(),
which calls uma_zalloc(). At the point of the call to get_pv_entry(), the
lock isn't necessary and holding it could lead to recursive acquisition,
which isn't allowed.
that the page's busy flag could be relied upon to synchronize access to the
pv list. I don't any longer. See, for example, the call to
pmap_insert_entry() from pmap_copy().)
(short) types for the port arg of inb() (rev.1.56). The warning started
working for u_short types with gcc-3.3. The pessimizations exposed
by this been fixed except for the cx and oltr drivers where the breakage
of the warning has been pushed to the drivers.
completenss. The pessimization is tiny compared with i/o port slowness
except on very old machines, but code that used signed short types for
i/o ports was unpessimized long ago, and the macro that detected it
recently started working for u_short types too. Use of bus space
should have made this moot long ago.
Not tested at runtime by: bde
they haven't been counted before. This test was ommitted when bus_dmamap_load()
was merged into this function, and results in the pagesneeded field growing
without bounds when multiple deferrals happen.
Thanks to Paul Saab for beating his head against this for a few hours =-)
- Move the enabling of interrupts out of assembly and into C a few
instructions later at cpu_critical_fork_exit(). This puts more of the
MD critical section implementation under the MD critical section API
making it easier to test and develop alternative implementations.
Also change "Auto mode" to use a "special" value
instead of 0, and define and document it.
I had thought libpthread had already been switched to use auto mode but
it appears that patch hasn't been committed yet.
Discussed with: Davidxu
there is code that blindly allocates LDTEs starting at slot 6
and I quess it doesn't really matter to us if they overwrite the BSDI
syscall slot, since it isn't a BSDI binary. Also add some code to help track
down other such users (commented out for now).
Reviewed by: deischen@
type. We know about header types 0, 1 and 2. Ignore the rest in the
MD i386 code when we're looking for bridges. You cannot look at the
vendor tag. And if you don't you certainly can't look at function > 0
if the device isn't there.
The new soekris boards' GEODE cpu has issues with the old way. This
is reported to have fixed it.
MFC After: 2 days
considered to be good to try when it otherwise has no clue about which
interrupts to try. This is a band-aide and we really should try to
balance the IRQs that we arbitrarily pick, but it should help some
people that would otherwise get bad IRQs.
The other option would be to remove it, but I can imagine it may be useful
for the forseeable future as we fiddle with segments in KSE and thr libraries,
that while many maps can exist and be loaded per tag, bus_dmamap_load() and
friends can only be called on one map at a time from the tag. This is
enforced via the mutex arguments in the tag.
Fixing this bug means that s/g lists can be arbitrarily long in length, and
also removes an ugly GNU-ism from the code. No API or ABI change is
incurred. Similar changes for other platforms is forthcoming.
created not only with UMA_ZONE_VM but also with UMA_ZONE_NOFREE. In
the i386 case in particular, the pmap code would hook a special
page allocation routine that allocated from kernel_map and not kmem_map,
and so when/if the pageout daemon drained the zones, it could actually
push out slabs from the PV ENTRY zone but call UMA's default page_free,
which resulted in pages allocated from kernel_map being freed to
kmem_map; bad. kmem_free() ignores the return value of the
vm_map_delete and just returns. I'm not sure what the exact
repercussions could be, but it doesn't look good.
In the PAE case on i386, we also set-up a zone in pmap, so be
conservative for now and make that zone also ZONE_NOFREE and
ZONE_VM. Do this for the pmap zones for the other archs too,
although in some cases it may not be entirely necessarily. We'd
rather be safe than sorry at this point.
Perhaps all UMA_ZONE_VM zones should by default be also
UMA_ZONE_NOFREE?
May fix some of silby's crashes on the PV ENTRY zone.
or free a LDT entry. The function has following prototype:
int i386_set_ldt(int start_sel, union descriptor *descs, int num_sels);
Added Features:
o If start_sel is 0, num_sels is 1 and the descriptor pointed to by descs
is legal, then i386_set_ldt() will allocate a descriptor and return its
selector numbe
o If num_descs is 1, start_sels is valid, and descs is NULL, then
i386_set_ldt() will free that descriptor (making it available to be real-
located again later).
o If num_descs is 0, start_sels is 0 and descs is NULL then, as a special
case, i386_set_ldt() will free all descriptors.
Reviewed by: julian
use "\n\" instead of "\" at the end of each source line, and don't use
semicolons). Fixed some older style bugs on the same lines (mainly
English errors in comments).
with up to date comments. This fixes booting kernels with boot2
(except for loss of the features provided by loader) and is suitable
for MFC. Contrary to the old comments, most loaders don't clear the bss.
biosboot lost clearing of the bss in a code crunch in 1997, and boot2
never did it.
kan didn't notice the problem with gcc-3.3 putting variables that are
initialized to 0 in the bss until after committing gcc-3.3 because he
was already using essentially this patch. Before gcc-3.3, only the
non-critical `bootdev' variable was clobbered by clearing the bss.
MFC after: 3 days
HIDENAME() macro seems to be unimplementable in C. (HIDENAME() used
to use invalid token pasting using ## for the STDC case until gcc
started rejecting that; now it uses unportable token pasting using
juxtaposition in all cases.) This reduces use of HIDENAME() in the
kernel to only i386 and amd64 profiling code so that it doesn't bite
most kernels whenever gcc becomes stricter. Problems with HIDENAME()
in userland are smaller because userland mostly doesn't use strict
flags yet. There are some advantages to hiding the name of mcount,
but newer arches shouldn't do it; only amd64 does.
MFC after: 3 days
On second thoughts hide tmpstk better by staticizing it.
in the `video_state' structure, to larger ones (from u_char to
u_short). Each can now hold values at least as large as the
size of the array it is meant to point into.
This eliminates warnings printed by GCC 3.3.1 and hence makes
pcvt compilable using -Werror.
memory in bus_dmamem_alloc(). This is possible now that
contigmalloc() supports the M_ZERO flag.
- Remove the locking of Giant around calls to contigmalloc() since
contigmalloc() now grabs Giant itself.
contain the filedescriptor number on opens from userland.
The index is used rather than a "struct file *" since it conveys a bit
more information, which may be useful to in particular fdescfs and /dev/fd/*
For now pass -1 all over the place.
written as a template that when inlined is specialized for the caller
through constant value propagation and dead code elimination. Thus,
the specialized code that is generated for pmap_clear_reference() et
al. avoids several conditional branches inside of a loop.
fields in the low 32 bits of the local APIC ICR register. Use this macro
in place of APIC_RESV2_MASK when masking off existing bits from the ICR
when writing to it to send an IPI.
Tested by: scottl
LAZY_SWITCH changes. He pointed out the acpi code sets up an identity
mapping in the current vmspace and that got messed up by the %cr3 being
out of sync with the current page directory. As a workaround, restore
%cr3 across the sleep/resume. A more complete fix would be to undo the
lazy state and clear the pm_active bit from the borrowed pmap, but this
works and people are currently hurting. I'll clean this up.
This is mostly Ian's patch, plus a PAE tweak from me.
work when using a graphics chipset which identifies itself as
`VIA CLE266', used in some VIA EPIA boards. Two values need to be
patched in the VESA mode information structure: the widths of the modes
mentioned above are encoded in a format which was unknown to the VESA
module (and to my copy of the VBE spec.) whereas the window memory
segment values seem to be just incorrect.
I tested this on a VIA EPIA-M9000 and -M10000.
it to the bss section and skips the initialization. This causes all
sorts of havoc because the bogus bss zero code clobbered previously set
variables. All our supported boot loaders already zero the bss, even
kgzip for the elf case. Since we dont generate a.out kernels, the old
a.out bootblocks and the a.out kgzip are not a factor anymore.
reset them only if they were previously in use. Unconditionally
resetting the registers wipes them out frequently, which interferes
with their use for kernel debugging.
While I'm here, be less verbose in the associated comment of a
neighboring function.
Noticed by: bde
order to avoid the overhead of later page faults. In general, it
implements two cases: one for vnode-backed objects and one for
device-backed objects. Only the device-backed case is really
machine-dependent, belonging in the pmap.
This commit moves the vnode-backed case into the (relatively) new
function vm_map_pmap_enter(). On amd64 and i386, this commit only
amounts to code rearrangement. On alpha and ia64, the new machine
independent (MI) implementation of the vnode case is smaller and more
efficient than their pmap-based implementations. (The MI
implementation takes advantage of the fact that objects in -CURRENT
are ordered collections of pages.) On sparc64, pmap_object_init_pt()
hadn't (yet) been implemented.
disabled.
- Change the apm driver to match the acpi driver's behavior by checking to
see if the device is disabled in the identify routine instead of in the
probe routine. This way if the device is disabled it is never created.
Note that a few places (ips(4), Alpha SMP) used "disable" instead of
"disabled" for their hint names, and these hints must be changed to
"disabled". If this is a big problem, resource_disabled() can always be
changed to honor both names.
Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma. At the moment, this is used for the
asynchronous busdma_swi and callback mechanism. Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg. dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create(). The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.
sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms. The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.
If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.
Reviewed by: tmm, gibbs
implementation of a largely MI pmap_object_init_pt() for vnode-backed
objects. pmap_enter_quick() is implemented via pmap_enter() on sparc64
and powerpc.
- Correct a mismatch between pmap_object_init_pt()'s prototype and its
various implementations. (I plan to keep pmap_object_init_pt() as
the MD hook for device-backed objects on i386 and amd64.)
- Correct an error in ia64's pmap_enter_quick() and adjust its interface
to match the other versions. Discussed with: marcel
bus_dma async callback scheme. Note that sparc64 does not seem to do
async callbacks. Note that ia64 callbacks might not be MPSAFE at the
moment. Note that powerpc doesn't seem to do async callbacks due to
the implementation being incomplete.
Reviewed by: mostly silence on arch@
Several of the subtypes have an associated vnode which is used for
stuff like the f*() functions.
By giving the vnode a speparate field, a number of checks for the specific
subtype can be replaced simply with a check for f_vnode != NULL, and
we can later free f_data up to subtype specific use.
At this point in time, f_data still points to the vnode, so any code I
might have overlooked will still work.
to the machine-independent parts of the VM. At the same time, this
introduces vm object locking for the non-i386 platforms.
Two details:
1. KSTACK_GUARD has been removed in favor of KSTACK_GUARD_PAGES. The
different machine-dependent implementations used various combinations
of KSTACK_GUARD and KSTACK_GUARD_PAGES. To disable guard page, set
KSTACK_GUARD_PAGES to 0.
2. Remove the (unnecessary) clearing of PG_ZERO in vm_thread_new. In
5.x, (but not 4.x,) PG_ZERO can only be set if VM_ALLOC_ZERO is passed
to vm_page_alloc() or vm_page_grab().
while after the legacy device was added since this driver hangs from
legacy and not nexus.
- Make several methods non-static so they can be reused in a mptable
host -> pci bridge driver that will be added at a later date.
- Let legacy_pcib() use pcibios_pcib_route_interrupt() directly instead of
wrapping it in a private function. Originally, I thought I was going to
have the nexus_pcib() driver make a runtime APIC vs. 8259A check and call
the appropriate routing method (MPTable vs. PIR) that way, but it ended
up being cleaner to make nexus_pcib() just work with PIR and have a
separate host -> pci bridge driver for the mptable/apic case.
bridge lives on (i.e., the parent bus) when probing the PIR table for a
bus. This could cause the PCIBIOS PCI-PCI bridge driver to bogusly attach
to bridges that weren't in the PIR but whose parent bus was in the PIR.
we were passing in a void* representing the PCB of the parent thread.
Now we pass a pointer to the parent thread itself.
The prime reason for this change is to allow cpu_set_upcall() to copy
(parts of) the trapframe instead of having it done in MI code in each
caller of cpu_set_upcall(). Copying the trapframe cannot always be
done with a simply bcopy() or may not always be optimal that way. On
ia64 specifically the trapframe contains information that is specific
to an entry into the kernel and can only be used by the corresponding
exit from the kernel. A trapframe copied verbatim from another frame
is in most cases useless without some additional normalization.
Note that this change removes the assignment to td->td_frame in some
implementations of cpu_set_upcall(). The assignment is redundant.
A previous call to cpu_thread_setup() already did the exact same
assignment. An added benefit of removing the redundant assignment is
that we can now change td_pcb without nasty side-effects.
This change officially marks the ability on ia64 for 1:1 threading.
Not tested on: amd64, powerpc
Compile & boot tested on: alpha, sparc64
Functionally tested on: i386, ia64
on my part. The output asm looks correct with the previous commit in place
and it works on amd64, but on my laptop I got a spew of AE_BAD_PARAMETER
errors trying to unlock the acpi global lock.
and releasing ACPI global locks instead of (ab)using the pointers to those
locks as the constants. Also, rather than require that the address of
the lock be stored in a register, use a memory constraint allowing the
memory address to be used directly.
Noticed by: peter
Two tokens that don't together form a vaid preprocssor token cannot be
pasted together using ANSI-C token concatinatation. GCC 3.2's cpp, at least,
produces the desired result w/o using "##".
The current name is confusing, because it indicates to
the client that a bus_dmamap_sync() operation is not
necessary when the flag is specified, which is wrong.
The main purpose of this flag is to hint the underlying
architecture that DMA memory should be mapped in a coherent
way, but the architecture can ignore it. But if the
architecture does supports coherent mapping of memory, then
it makes bus_dmamap_sync() calls cheap.
This flag is the same as the one in NetBSD's Bus DMA.
Reviewed by: gibbs, scottl, des (implicitly)
Approved by: re@ (jhb)
BUS_DMASYNC_ definitions remain as before. The does not change the ABI,
and reverts the API to be a bit more compatible and flexible. This has
survived a full 'make universe'.
Approved by: re (bmah)
Thus, treat all page faults while in a critical section as fatal rather
than just those that occur with a non-empty spinlocks list. All such page
faults are fatal anyways. Calling trap_fatal() earlier increases the
chances of getting more useful panic messages and a possible DDB prompt.
Approved by: re (scottl)
- Fix visibilty test for LONG_BIT and WORD_BIT. `#if defined(__FOO_VISIBLE)'
is alays wrong because __FOO_VISIBLE is always defined (to 0 for
invisibility).
sys/<arch>/include/limits.h
sys/<arch>/include/_limits.h:
- Style fixes.
Submitted by: bde
Reviewed by: bsdmike
Approved by: re (scottl)
instead of taking the (userland) eflags from the trap frame and masking
out PSL_I. There is no need to inherit any flags from the forking process;
the old method however can cause flags set in userland for the forking
process to be bogusly set in kernel mode when the newly forked process
runs for the first time (in particular PSL_T, which is set for userland
when the process is single-stepped; this would cause trace traps in
kernel mode).
Approved by: re (jhb)
- Move struct sigacts out of the u-area and malloc() it using the
M_SUBPROC malloc bucket.
- Add a small sigacts_*() API for managing sigacts structures: sigacts_alloc(),
sigacts_free(), sigacts_copy(), sigacts_share(), and sigacts_shared().
- Remove the p_sigignore, p_sigacts, and p_sigcatch macros.
- Add a mutex to struct sigacts that protects all the members of the struct.
- Add sigacts locking.
- Remove Giant from nosys(), kill(), killpg(), and kern_sigaction() now
that sigacts is locked.
- Several in-kernel functions such as psignal(), tdsignal(), trapsignal(),
and thread_stopped() are now MP safe.
Reviewed by: arch@
Approved by: re (rwatson)
Remove DBL_DIG, DBL_MIN, DBL_MAX and their FLT_ counterparts, they
were marked for deprecation ever since SUSv1 at least.
Only define ULLONG_MIN/MAX and LLONG_MAX if long long type is
supported.
Restore a lost comment in MI _limits.h file and remove it from
sys/limits.h where it does not belong.
that were added to sparc64 and later powerpc, really should have been in
the MI area. But changing that now with insufficient preperation will
just cause too much pain.
Move MD_FETCH() to the MI sys/linker.h file to avoid another two copies
of it.
were, they are not safe to use outside of the kernel since these values
can change at kernel compile time - ie: we do not want them compiled into
userland binaries.
lot of work to make this driver work under current. In the past when
people wanted to remove xten, I was the only one in the way. After
talking to fsmp@ (last person to make real changes to this driver)
about this, I'm convinced it is better left in the dust-bin of history
Approved by: re@ (scottl)
syscall return values should be cleared. The system calls
getcontext() and swapcontext() want to return 0 on success
but these contexts can be switched to at a later time so
the return values need to be cleared in the saved register
sets. Other callers of get_mcontext() would normally want
the context without clearing the return values.
Remove the i386-specific context saving from the KSE code.
get_mcontext() is not i386-specific any more.
Fix a bad pointer in the alpha get_mcontext() code. The
context was being bcopy()'d from &td->tf_frame, but tf_frame
is itself a pointer, so the thread was being copied instead.
Spotted by jake.
Glanced at by: jake
Reviewed by: bde (months ago)
of the infrastructure for the gamma driver which was removed a while back.
The DRM_LINUX option is removed because the handler is now provided by the
linux compat code itself.
to get actual constant values. This is in preparation for machine/limits.h
retirement.
Discussed on: standards@
Submitted by: Craig Rodrigues <rodrigc@attbi.com> (*)
Modified by: kan
kern_sigprocmask() in the various binary compatibility emulators.
- Replace calls to sigsuspend(), sigaltstack(), sigaction(), and
sigprocmask() that used the stackgap with calls to the corresponding
kern_sig*() functions instead without using the stackgap.
cpu_switch_load_gs, cpu is in context switch, so don't enable interrupt.
because it is in context switch, it is expected sched_lock was held,
so don't PROC_LOCK(p) and psignal, it is LOR, probably we can
set a P_XSIGBUS like flag in p_sflags, and set TDF_ASTPENDING in
td_flags, in ast(), post a SIGBUS to process if P_XSIGBUS was set.
ethernet controller. The driver has been tested with the LinkSys
USB200M adapter. I know for a fact that there are other devices out
there with this chip but don't have all the USB vendor/device IDs.
Note: I'm not sure if this will force the driver to end up in the
install kernel image or not. Special magic needs to be done to exclude
it to keep the boot floppies from bloating again, someone please
advise.
Ignoring maxsegsz may lead to fatal data corruption for some devices.
ex. SBP-2/FireWire
We should apply this change to other platforms except for sparc64.
MFC after: 1 week
enum to an int and redefine the BUS_DMASYNC_* constants as
flags. This allows us to specify several operations in one
call to bus_dmamap_sync() as in NetBSD.
mechanism, and then excludes device drivers which have not been tested or
are known to not work with more than 4G of ram.
Sponsored by: DARPA, Network Associates Laboratories
backend for bus_dmamap_load_mbuf and bus_dmamap_load_uio.
- Increaes MAX_BPAGES to 512. Less than this causes fxp to quickly runs out
of bounce pages.
- Add an argument to reserve_bounce_pages indicating wether this operation
should fail or be queued for later processing if we run out of memory.
The EINPROGRESS return value is not handled properly by consumers of
bus_dmamap_load_mbuf.
- If bounce buffers are required allocate minimum 1 bounce page at map
creation time. If maxsize was small previously this could get truncated
to 0 and the drivers would quickly run out of bounce pages.
- Fix a bug handling the return value of alloc_bounce_pages at map creation
time. It returns the number of pages allocated, not 0 on success.
- Use bus_addr_t for physical addresses to avoid truncation.
- Assert that the map is non-null and not the no bounce map in
add_bounce_pages.
Sponsored by: DARPA, Network Associates Laboratories
the top of the address space to be reclaimed. The problem is that with
the APTD gone the mapable kernel address space runs right to the end of
the 32 bit address space. As a max this is 0x100000000, which can't be
represented in 32 bits, so we have to use ptd entry n-1 and pte offset
n-1, instead of ptd entry n and pte offset 0. There's still 1 page we
can't use, but we gain just under 4 megs of kva (8 megs with PAE).
Sponsored by: DARPA, Network Associates Laboratories
to take care of the KAME IPv6 code which needs ovbcopy() because NetBSD's
bcopy() doesn't handle overlap like ours.
Remove all implementations of ovbcopy().
Previously, bzero was a function pointer on i386, to save a jmp to
bzero_vector. Get rid of this microoptimization as it only confuses
things, adds machine-dependent code to an MD header, and doesn't really
save all that much.
This commit does not add my pagezero() / pagecopy() code.
Move the remaining bits of <sys/diskslice.h> to <i386/include/bootinfo.h>
Move i386/pc98 specific bits from <sys/reboot.h> to
<i386/include/bootinfo.h> as well.
Adjust includes in sys/boot accordingly.
as it could be and can do with some more cleanup. Currently its under
options LAZY_SWITCH. What this does is avoid %cr3 reloads for short
context switches that do not involve another user process. ie: we can
take an interrupt, switch to a kthread and return to the user without
explicitly flushing the tlb. However, this isn't as exciting as it could
be, the interrupt overhead is still high and too much blocks on Giant
still. There are some debug sysctls, for stats and for an on/off switch.
The main problem with doing this has been "what if the process that you're
running on exits while we're borrowing its address space?" - in this case
we use an IPI to give it a kick when we're about to reclaim the pmap.
Its not compiled in unless you add the LAZY_SWITCH option. I want to fix a
few more things and get some more feedback before turning it on by default.
This is NOT a replacement for Bosko's lazy interrupt stuff. This was more
meant for the kthread case, while his was for interrupts. Mine helps a
little for interrupts, but his helps a lot more.
The stats are enabled with options SWTCH_OPTIM_STATS - this has been a
pseudo-option for years, I just added a bunch of stuff to it.
One non-trivial change was to select a new thread before calling
cpu_switch() in the first place. This allows us to catch the silly
case of doing a cpu_switch() to the current process. This happens
uncomfortably often. This simplifies a bit of the asm code in cpu_switch
(no longer have to call choosethread() in the middle). This has been
implemented on i386 and (thanks to jake) sparc64. The others will come
soon. This is actually seperate to the lazy switch stuff.
Glanced at by: jake, jhb
a pointer that is in user space. It will be used as the basic primitive
for a kernel supported user space lock implementation.
- Implement this function in x86's support.s
- Provide stubs that return -1 in all other architectures. Implementations
will follow along shortly.
Reviewed by: jake
a follow on commit to kern_sig.c
- signotify() now operates on a thread since unmasked pending signals are
stored in the thread.
- PS_NEEDSIGCHK moves to TDF_NEEDSIGCHK.
- Change all consumers to pass in a thread.
Right now this does not cause any functional changes but it will be important
later when signals can be delivered to specific threads.
kernel opition 'options PAE'. This will only work with device drivers which
either use busdma, or are able to handle 64 bit physical addresses.
Thanks to Lanny Baron from FreeBSD Systems for the loan of a test machine
with 6 gigs of ram.
Sponsored by: DARPA, Network Associates Laboratories, FreeBSD Systems
accessing an alternate address space this causes 1 page table page at
a time to be mapped in, rather than using the recursive mapping technique
to map in an entire alternate address space. The recursive mapping
technique changes large portions of the address space and requires global
tlb flushes, which seem to cause problems when PAE is enabled. This will
also allow IPIs to be avoided when mapping in new page table pages using
the same technique as is used for pmap_copy_page and pmap_zero_page.
Sponsored by: DARPA, Network Associates Laboratories
This keeps the logical cpu's halted in the idle loop. By default
the logical cpu's are halted at startup. It is also possible to
halt any cpu in the idle loop now using machdep.hlt_cpus.
Examples of how to use this:
machdep.hlt_cpus=1 halt cpu0
machdep.hlt_cpus=2 halt cpu1
machdep.hlt_cpus=4 halt cpu2
machdep.hlt_cpus=3 halt cpu0,cpu1
Reviewed by: jhb, peter
1) Its critical for HTT. There's less foot-shooting opportunity.
2) I've seen significant improvements in interactive response to commands
over ssh sessions. I assume this is less lock contention.
3) As incentive to finish the idle cpu IPI wakeup stuff.
4) The machine on my desk was blowing hot air in my general direction
because somebody forgot to turn the hlt on, and it saves 50 watts per
cpu..
The machdep.cpu_idle_hlt sysctl is still available, but now the default
is the same as on UP kernels.