on x86 and use that to implement stop_emulating() in the fpu/npx code.
Reimplement start_emulating() in the non-XEN case by using load_cr0() and
rcr0() instead of the 'lmsw' and 'smsw' instructions. Intel explicitly
discourages the use of 'lmsw' and 'smsw' on 80386 and later processors in
the description of these instructions in Volume 2 of the ADM.
Reviewed by: kib
MFC after: 1 month
64bit and 32bit ABIs. As a side-effect, it enables AVX on capable
CPUs.
In particular:
- Query the CPU support for XSAVE, list of the supported extensions
and the required size of FPU save area. The hw.use_xsave tunable is
provided for disabling XSAVE, and hw.xsave_mask may be used to
select the enabled extensions.
- Remove the FPU save area from PCB and dynamically allocate the
(run-time sized) user save area on the top of the kernel stack,
right above the PCB. Reorganize the thread0 PCB initialization to
postpone it after BSP is queried for save area size.
- The dumppcb, stoppcbs and susppcbs now do not carry the FPU state as
well. FPU state is only useful for suspend, where it is saved in
dynamically allocated suspfpusave area.
- Use XSAVE and XRSTOR to save/restore FPU state, if supported and
enabled.
- Define new mcontext_t flag _MC_HASFPXSTATE, indicating that
mcontext_t has a valid pointer to out-of-struct extended FPU
state. Signal handlers are supplied with stack-allocated fpu
state. The sigreturn(2) and setcontext(2) syscall honour the flag,
allowing the signal handlers to inspect and manipilate extended
state in the interrupted context.
- The getcontext(2) never returns extended state, since there is no
place in the fixed-sized mcontext_t to place variable-sized save
area. And, since mcontext_t is embedded into ucontext_t, makes it
impossible to fix in a reasonable way. Instead of extending
getcontext(2) syscall, provide a sysarch(2) facility to query
extended FPU state.
- Add ptrace(2) support for getting and setting extended state; while
there, implement missed PT_I386_{GET,SET}XMMREGS for 32bit binaries.
- Change fpu_kern KPI to not expose struct fpu_kern_ctx layout to
consumers, making it opaque. Internally, struct fpu_kern_ctx now
contains a space for the extended state. Convert in-kernel consumers
of fpu_kern KPI both on i386 and amd64.
First version of the support for AVX was submitted by Tim Bird
<tim.bird am sony com> on behalf of Sony. This version was written
from scratch.
Tested by: pho (previous version), Yamagi Burmeister <lists yamagi org>
MFC after: 1 month
safer for i386 because it can be easily over 4 GHz now. More worse, it can
be easily changed by user with 'machdep.tsc_freq' tunable (directly) or
cpufreq(4) (indirectly). Note it is intentionally not used in performance
critical paths to avoid performance regression (but we should, in theory).
Alternatively, we may add "virtual TSC" with lower frequency if maximum
frequency overflows 32 bits (and ignore possible incoherency as we do now).
mark user FPU context initialized, if current context is user context.
It was reversed in r215865, by inadequate change of this code fragment
to a call to fpuuserinited()/npxuserinited().
The issue is only relevant for in-kernel users of FPU.
Reported by: Jan Henrik Sylvester <me janh de>, Mike Tancsa <mike sentex net>
Tested by: Mike Tancsa
MFC after: 3 days
functions, they are unused. Remove 'user' from npxgetuserregs()
etc. names.
For {npx,fpu}{get,set}regs(), always use pcb->pcb_user_save for FPU
context storage. This eliminates the need for ugly copying with
overwrite of the newly added and reserved fields in ucontext on i386
to satisfy alignment requirements for fpusave() and fpurstor().
pc98 version was copied from i386.
Suggested and reviewed by: bde
Tested by: pho (i386 and amd64)
MFC after: 1 week
silently converts 'fld' to 'flds', without taking the actual variable
type into account (!), but clang's integrated assembler rightfully
complains about it.
Discussed with: cperciva
removal, MFi386 r209198:
Use critical sections instead of disabling local interrupts to ensure
the consistency between PCPU fpcurthread and the state of FPU.
Reviewed by: bde
Tested by: pho
believed that all 486-class CPUs FreeBSD is capable to run on, either
have no FPU and cannot use external coprocessor, or have FPU on the
package and can use #MF.
Reviewed by: bde
Tested by: pho (previous version)
FPU registers for copying. Remove the switch table and jumps from
bcopy/bzero/... to the actual implementation.
As a side-effect, i486-optimized bzero is removed.
Reviewed by: bde
Tested by: pho (previous version)
FPU/SSE hardware. Caller should provide a save area that is chained
into the stack of the areas; pcb save_area for usermode FPU state is
on top. The pcb now contains a pointer to the current FPU saved area,
used during FPUDNA handling and context switches. There is also a
facility to allow the kernel thread to use pcb save_area.
Change the dreaded warnings "npxdna in kernel mode!" into the panics
when FPU usage is not registered.
KPI discussed with: fabient
Tested by: pho, fabient
Hardware provided by: Sentex Communications
MFC after: 1 month
shared and generalized between our current amd64, i386 and pc98.
This is just an initial step that should lead to a more complete effort.
For the moment, a very simple porting of cpufreq modules, BIOS calls and
the whole MD specific ISA bus part is added to the sub-tree but ideally
a lot of code might be added and more shared support should grow.
Sponsored by: Sandvine Incorporated
Reviewed by: emaste, kib, jhb, imp
Discussed on: arch
MFC: 3 weeks
- ATPIC, on pc98 is never defined somewhere, differently from i386.
Turn its compilation to be conditional as i386 does. [1]
[0] Reported by: nyan
[1] Submitted by: nyan
LAPIC may lead to aliasing for softclock and profclock because frequencies
are sized in order to fit mainly hardclock.
atrtc used to take care of the softclock and profclock and it does still
do, if the LAPIC can't handle the clocks properly.
Revert the change when the LAPIC started taking charge of all three of
them and let atrtc handle softclock and profclock if not explicitly
requested. Such request can be made setting != 0 the new tunable
machdep.lapic_allclocks or if the new device ATPIC is not present
within the i386 kernel config (atrtc is linked to atpic presence).
Diagnosed by: Sandvine Incorporated
Reviewed by: jhb, emaste
Sponsored by: Sandvine Incorporated
MFC: 3 weeks
functions are selfcontained (ie. they touch only isa_dma.c static variables
and hardware) so a private lock is sufficient to prevent races. This changes
only i386/amd64 while there are also isa_dma functions for ia64/sparc64.
Sparc64 are ones empty stubs and ia64 ones are unused as ia64 does not
have isa (says marcel).
This patch removes explicit locking of Giant from a few drivers (there
are some that requires this but lack ones - this patch fixes this) and
also removes the need for implicit locking of Giant from attach routines
where it's provided by newbus.
Approved by: ed (mentor, implicit)
Reviewed by: jhb, attilio (glanced by)
Tested by: Giovanni Trematerra <giovanni.trematerra gmail com>
IA64 clue: marcel
- Add vesa kernel options for amd64.
- Connect libvgl library and splash kernel modules to amd64 build.
- Connect manual page dpms(4) to amd64 build.
- Remove old vesa/dpms files.
Submitted by: paradox <ddkprog yahoo com> [1], swell k at gmail.com
(with some minor tweaks)
- 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)
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.
- 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.
the "Get Scan Line Length" function fails, as it does in Parallels
(in Version 2.2, Build 2112 at least).
PR: i386/127367
Obtained from: DragonFly
Submitted by: Pedro Giffuni
MFC after: 1 month
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.
in AMD FPUs:
- Do not clear the affected state in the case that the FPU registers for
the thread that already owns the FPU are changed via fpu_setregs(). The
only local information the thread would see is its own state in that
case.
- Fix a type mismatch for the dummy variable used in a "fld". It accepts
a float, not a double.
Reviewed by: bde
Approved by: so (cperciva)
MFC after: 1 month
ABIs:
- Store the FPU initial control word in the pcb for each thread.
- When first using the FPU, load the initial control word after restoring
the clean state if it is not the standard control word.
- Provide a correct control word for Linux/i386 binaries under
FreeBSD/amd64.
- Adjust the control word returned for fpugetregs()/npxgetregs() when a
thread hasn't used the FPU yet to reflect the real initial control
word for the current ABI.
- The Linux/i386 ABI for FreeBSD/i386 now properly sets the right control
word instead of trashing whatever the current state of the FPU is.
Reviewed by: bde
- Remove the control word parameter to npxinit(). It was always set
to __INITIAL_NPXCW__.
- Remove npx_cleanstate_ready as the cleanstate is always initalized
when it is used.
- Improve the handling of the case when the FPU isn't present. Now
the npx0 device no longer succeeds in its probe so all of npx_attach()
is skipped. Also, we allow this case with SMP (though that shouldn't
actually occur as all i386 systems that support SMP have FPUs) now.
SMP was only an issue back when we had an FPU emulator which was not
per-CPU.
- MFamd64: Clear some of the state in npx_cleanstate rather than leaving
it as garbage.
- MFamd64: When a user thread first uses the FPU, use npx_cleanstate for
the initial FPU state.
Reviewed by: bde
Log:
- merge in latest xenbus from dfr's xenhvm
- fix race condition in xs_read_reply by converting tsleep to mtx_sleep
Log:
unmask evtchn in bind_{virq, ipi}_to_irq
Log:
- remove code for handling case of not being able to sleep
- eliminate tsleep - make sleeps atomic
