page table fault. Use this when fetching the instruction bytes from the guest
memory.
Also modify the lapic_mmio() API so that a decoded instruction is fed into it
instead of having it fetch the instruction bytes from the guest. This is
useful for hardware assists like SVM that provide the faulting instruction
as part of the vmexit.
AP needs to be activated by spinning up an execution context for it.
The local apic emulation is now completely done in the hypervisor and it will
detect writes to the ICR_LO register that try to bring up the AP. In response
to such writes it will return to userspace with an exit code of SPINUP_AP.
Reviewed by: grehan
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
- Add generic support for opcodes that are escape bytes used for
multi-byte opcodes (such as the 0x0f prefix). Use this to replace
the hard-coded 0x0f special case and add support for three-byte
opcodes that use the 0x0f38 prefix.
- Decode all Intel VMX instructions. invept and invvpid in particular are
three-byte opcodes that use the 0x0f38 escape prefix.
- Rework how the special 'SDEP' size flag works such that the default
instruction name (i_name) is the instruction when the data size
prefix (0x66) is not specified, and the alternate name in i_extra is
used when the prefix is included.
- Add a new 'ADEP' size flag similar to 'SDEP' except that it chooses
between i_name and i_extra based on the address size prefix (0x67).
Use this to fix the decoding for jrcxz vs jecxz which is determined
by the address size prefix, not the operand size prefix. Also, jcxz
is not possible in 64-bit mode, but jrcxz is the default instruction
for that opcode.
- Add support for handling instructions that have a mandatory 'rep'
prefix (this means not outputting the 'repe ' prefix until determining
if it is used as part of an opcode). Make 'pause' less of a special
case this way.
- Decode 'cmpxchg16b' and 'cdqe' which are variants of other instructions
but with a REX.W prefix.
MFC after: 1 month
functions that manage PV entries. Specifically, remove the PV entry from
the containing PV list only after the corresponding PTE is destroyed.
Update the pmap's wired mapping count in pmap_enter() before the PV list
lock is acquired.
natively rather than hand-assembled versions. For xgetbv/xsetbv, add a
wrapper API to deal with xcr* registers: rxcr() and load_xcr().
Reviewed by: kib
MFC after: 1 month
at the point that it calls get_pv_entry(). Thus, pmap_enter()'s PV list
lock pointer must be passed to get_pv_entry() for those rare occasions
when get_pv_entry() calls reclaim_pv_chunk().
Update some related comments.
pmap_remove(). The execution of these functions is no longer serialized
by the pvh global lock.
Make some stylistic changes to the affected code for the sake of
consistency with related code elsewhere in the pmap.
to add PV list locking to pmap_pv_demote_pde(), it is necessary to change
the way that pmap_pv_demote_pde() allocates PV entries. Specifically,
once pmap_pv_demote_pde() begins modifying the PV lists, it can't allocate
any new PV chunks, because that could require the PV list lock to be
dropped. So, all necessary PV chunks must be allocated in advance. To my
surprise, this new approach is a few percent faster than the old one.
usermode, using shared page. The structures and functions have vdso
prefix, to indicate the intended location of the code in some future.
The versioned per-algorithm data is exported in the format of struct
vdso_timehands, which mostly repeats the content of in-kernel struct
timehands. Usermode reading of the structure can be lockless.
Compatibility export for 32bit processes on 64bit host is also
provided. Kernel also provides usermode with indication about
currently used timecounter, so that libc can fall back to syscall if
configured timecounter is unknown to usermode code.
The shared data updates are initiated both from the tc_windup(), where
a fast task is queued to do the update, and from sysctl handlers which
change timecounter. A manual override switch
kern.timecounter.fast_gettime allows to turn off the mechanism.
Only x86 architectures export the real algorithm data, and there, only
for tsc timecounter. HPET counters page could be exported as well, but
I prefer to not further glue the kernel and libc ABI there until
proper vdso-based solution is developed.
Minimal stubs neccessary for non-x86 architectures to still compile
are provided.
Discussed with: bde
Reviewed by: jhb
Tested by: flo
MFC after: 1 month
no longer necessary for free_pv_entry() to be serialized by the pvh global
lock.
Retire pmap_insert_entry() and pmap_remove_entry(). Once upon a time,
these functions were called from multiple places within the pmap. Now,
each has only one caller.
pmap_enter_quick(). These functions are no longer serialized by the pvh
global lock.
There is no need to release the PV list lock before calling free_pv_chunk()
in pmap_remove_pages().
- Stateful TCP offload drivers for Terminator 3 and 4 (T3 and T4) ASICs.
These are available as t3_tom and t4_tom modules that augment cxgb(4)
and cxgbe(4) respectively. The cxgb/cxgbe drivers continue to work as
usual with or without these extra features.
- iWARP driver for Terminator 3 ASIC (kernel verbs). T4 iWARP in the
works and will follow soon.
Build-tested with make universe.
30s overview
============
What interfaces support TCP offload? Look for TOE4 and/or TOE6 in the
capabilities of an interface:
# ifconfig -m | grep TOE
Enable/disable TCP offload on an interface (just like any other ifnet
capability):
# ifconfig cxgbe0 toe
# ifconfig cxgbe0 -toe
Which connections are offloaded? Look for toe4 and/or toe6 in the
output of netstat and sockstat:
# netstat -np tcp | grep toe
# sockstat -46c | grep toe
Reviewed by: bz, gnn
Sponsored by: Chelsio communications.
MFC after: ~3 months (after 9.1, and after ensuring MFC is feasible)
performing the return to usermode using full return path. This
consolidates the handling of exceptional situations in less number of
places, and is less code as well.
Reviewed by: jhb
MFC after: 1 week
layer, but it is read directly by the MI VM layer. This change introduces
pmap_page_is_write_mapped() in order to completely encapsulate all direct
access to PGA_WRITEABLE in the pmap layer.
Aesthetics aside, I am making this change because amd64 will likely begin
using an alternative method to track write mappings, and having
pmap_page_is_write_mapped() in place allows me to make such a change
without further modification to the MI VM layer.
As an added bonus, tidy up some nearby comments concerning page flags.
Reviewed by: kib
MFC after: 6 weeks
