- Clear the current thread's TLS pointer on exec. Previously the TLS
pointer (and register) remain unchanged.
- Explicitly clear the TLS pointer when new threads are created.
- Make md_tls_tcb_offset per-process instead of per-thread.
The layout of the TLS and TCB are identical for all threads in a
process, it is only the TLS pointer values themselves that vary by
thread. This also makes setting md_tls_tcb_offset in
cpu_set_user_tls() redundant with the setting in exec_setregs(), so
only set it in exec_setregs().
Submitted by: Alfredo Mazzinghi (1)
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24957
Match other architectures and print CPU information during
cpu_startup(). In particular, this prints the information after the
message buffer is initialized which allows it to be retrieved after
boot via dmesg(8).
While here, add some extern declarations to <machine/md_var.h> in
place of duplicated declarations in various source files.
Reviewed by: brooks
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24936
Rather than walking all of cpu_switch looking for the sequence of
instructions to patch, add a global label at the location that needs
the patch applied.
Reviewed by: brooks, Alfredo Mazzinghi <alfredo.mazzinghi_cl.cam.ac.uk>
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24931
The use of "int" here caused the compiler to believe that it needs to
insert a "sll $n, $n, 0" to sign extend as part of the implicit cast
to uint64_t.
Submitted by: Nathaniel Filardo <nwf20@cl.cam.ac.uk>
Reviewed by: brooks, arichardson
Obtained from: CheriBSD
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24457
This is a lock-based emulation of 64-bit atomics for kernel use, split off
from an earlier patch by jhibbits.
This is needed to unblock future improvements that reduce the need for
locking on 64-bit platforms by using atomic updates.
The implementation allows for future integration with userland atomic64,
but as that implies going through sysarch for every use, the current
status quo of userland doing its own locking may be for the best.
Submitted by: jhibbits (original patch), kevans (mips bits)
Reviewed by: jhibbits, jeff, kevans
Differential Revision: https://reviews.freebsd.org/D22976
This is a 32-bit structure embedded in each vm_page, consisting mostly
of page queue state. The use of a structure makes it easy to store a
snapshot of a page's queue state in a stack variable and use cmpset
loops to update that state without requiring the page lock.
This change merely adds the structure and updates references to atomic
state fields. No functional change intended.
Reviewed by: alc, jeff, kib
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D22650
o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
All Rights Reserved on same line as other copyright holders (but not
me). Other such holders are also listed last where it's clear.
Most of this diff is refactoring to reduce duplication between the different
acq_ and rel_ variants.
Differential Revision: https://reviews.freebsd.org/D21822
For ll/sc architectures, atomic(9) allows failure modes where *old == val
due to write failure and callers should compensate for this. Do not retry on
failure, just leave 0 in ret and fail the operation if we couldn't sc it.
This lets the caller determine if it should retry or not.
Reviewed by: kib
Looks ok: imp
Differential Revision: https://reviews.freebsd.org/D21836
This is derived from similar work done in r310481 for i386 and r312610 for
armv6/armv7. Additionally, use a critical section to keep the thread
pinned for per-CPU operations instead of completely disabling local interrupts.
No objections from: adrian, jmallett, imp
Differential Revision: https://reviews.freebsd.org/D18593
The symbol version for _mcount was removed 12 years ago in r169525 from
gmon/Symbol.map, to be added to the per-arch Symbol.map. mips was overlooked
in this, so _mcount has no symver. Add it back to where it should have been,
rather than where it would go if it were added today, since we're correcting
a historical mistake.
Additionally, _mcount is getting thrown into .mdebug.abi32 in the llvm80/90
world as it's not getting explicitly thrown into .text, so do this now. This
fixes the libc build that was previously failing due to relocations in
.mdebug.abi32. This is specifically due to the way clang's integrated AS
works and that they emit the .mdebug.abiNN section early in the process. An
LLVM bug has been submitted[0] and an agreement has been made that the
mips backend should switch to .text following .mdebug.abiNN for
compatibility.
[0] https://bugs.llvm.org/show_bug.cgi?id=43119
Reviewed by: imp, arichardson
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21435
Many extern struct pcpu <something>__pcpu declarations were
copied/pasted in sources. The issue is that the definition is MD, but
it cannot be provided by machine/pcpu.h due to actual struct pcpu
defined in sys/pcpu.h later than the inclusion of machine/pcpu.h.
This forced the copying when other code needed direct access to
__pcpu. There is no way around it, due to machine/pcpu.h supplying
part of struct pcpu fields.
To work around the problem, add a new machine/pcpu_aux.h header, which
should fill any needed MD definitions after struct pcpu definition is
completed. This allows to remove copies of __pcpu spread around the
source. Also on x86 it makes it possible to remove work arounds like
OFFSETOF_CURTHREAD or clang specific warnings supressions.
Reported and tested by: lwhsu, bcran
Reviewed by: imp, markj (previous version)
Discussed with: jhb
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21418
machine/regnum.h ends up being included by sys/procfs.h and sys/ptrace.h via
machine/reg.h. Many of the regnum definitions are too short and too generic
to be exposing to any userland application including one of these two
headers. Moreover, these actively cause build failures in googletest
(template <typename T1 ...> expanding to template <typename 9 ...>).
Hide the definitions behind _KERNEL or _WANT_MIPS_REGNUM, and patch all of
the userland consumers to define as needed.
Discussed with: imp, jhb
Reviewed by: imp, jhb
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21330
doing so adds more flexibility with less redundant code.
Reviewed by: jhb, markj, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D21250
Add the infrastructure to allow MD procctl(2) commands, and use it to
introduce amd64 PTI control and reporting. PTI mode cannot be
modified for existing pmap, the knob controls PTI of the new vmspace
created on exec.
Requested by: jhb
Reviewed by: jhb, markj (previous version)
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D19514
Skylake Xeons.
See SDM rev. 68 Vol 3 4.6.2 Protection Keys and the description of the
RDPKRU and WRPKRU instructions.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D18893
fcmpset returns true/false as a int, so make the return types and
variables match the int to be consistent with other arch.
Reviewed by: cognet@
Differential Revision: https://reviews.freebsd.org/D18557
MIPS64 has 64-bit longs, so use uint64_t for it, otherwise uint32_t.
sizeof(long) == sizeof(ptr) for all platforms, so define
atomic_swap_ptr in terms of atomic_swap_long.
Submitted by: hps@
Replace a call to DELAY(1) with a new cpu_lock_delay() KPI. Currently
cpu_lock_delay() is defined to DELAY(1) on all platforms. However,
platforms with a DELAY() implementation that uses spin locks should
implement a custom cpu_lock_delay() doesn't use locks.
Reviewed by: kib
MFC after: 3 days
All platforms except powerpc use the same values and powerpc shares a
majority of them.
Go ahead and declare AT_NOTELF, AT_UID, and AT_EUID in favor of the
unused AT_DCACHEBSIZE, AT_ICACHEBSIZE, and AT_UCACHEBSIZE for powerpc.
Reviewed by: jhb, imp
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D17397
Move definitions from cpuregs.h into the cca.h, and include cca.h into vm.h.
This is required to make MIPS MD memattr definitions usable in userspace.
Sponsored by: The FreeBSD Foundation, Mellanox Technologies
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D15583
- Change pcpu zone consumers to use a stride size of PAGE_SIZE.
(defined as UMA_PCPU_ALLOC_SIZE to make future identification easier)
- Allocate page from the correct domain for a given cpu.
- Don't initialize pc_domain to non-zero value if NUMA is not defined
There are some misconceptions surrounding this field. It is the
_VM_ NUMA domain and should only ever correspond to valid domain
values as understood by the VM.
The former slab size of sizeof(struct pcpu) was somewhat arbitrary.
The new value is PAGE_SIZE because that's the smallest granularity
which the VM can allocate a slab for a given domain. If you have
fewer than PAGE_SIZE/8 counters on your system there will be some
memory wasted, but this is obviously something where you want the
cache line to be coming from the correct domain.
Reviewed by: jeff
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D15933
Note that GDB at least implements single stepping for MIPS using software
breakpoints explicitly rather than using PT_STEP, so this has only been
tested via tests in ptrace_test which now pass rather than fail.
- Fix several places to use uintptr_t instead of int for virtual addresses.
- Check for errors from ptrace_read_int() when setting a breakpoint for a
step.
- Properly check for errors from ptrace_write_int() as it returns non-zero,
not negative values on failure.
- Change the error returns for ptrace_read_int() and ptrace_write_int() from
ENOMEM to EFAULT.
- Clear a single step breakpoint when it traps rather than waiting for it
to be cleared from ptrace(). This matches the behavior of the arm port
and in general seems a bit more reliable than waiting for ptrace() to
clear it via FIX_SSTEP.
- Drop the PROC_LOCK around ptrace_write_int() in ptrace_clear_single_step()
since it can sleep.
- Reorder the breakpoint handler in trap() to only read the instruction if
the address matches the current thread's breakpoint address.
- Replace various #if 0'd debugging printfs with KTR_PTRACE traces.
Tested on: mips64
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.
Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c. A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.
Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.
Reviewed by: kib, cem, jhb, jtl
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14941
Remove NO_FUEWORD so the 'e' variants are wrapped by the non-'e'
variants. This is more correct and leaves sparc64 as the outlier.
Reviewed by: jmallett, kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14603
correctly for the data contained on each memory page.
There are several components to this change:
* Add a variable to indicate the start of the R/W portion of the
initial memory.
* Stop detecting NX bit support for each AP. Instead, use the value
from the BSP and, if supported, activate the feature on the other
APs just before loading the correct page table. (Functionally, we
already assume that the BSP and all APs had the same support or
lack of support for the NX bit.)
* Set the RW and NX bits correctly for the kernel text, data, and
BSS (subject to some caveats below).
* Ensure DDB can write to memory when necessary (such as to set a
breakpoint).
* Ensure GDB can write to memory when necessary (such as to set a
breakpoint). For this purpose, add new MD functions gdb_begin_write()
and gdb_end_write() which the GDB support code can call before and
after writing to memory.
This change is not comprehensive:
* It doesn't do anything to protect modules.
* It doesn't do anything for kernel memory allocated after the kernel
starts running.
* In order to avoid excessive memory inefficiency, it may let multiple
types of data share a 2M page, and assigns the most permissions
needed for data on that page.
Reviewed by: jhb, kib
Discussed with: emaste
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D14282
We don't support float in the boot loaders, so don't include
interfaces for float or double in systems headers. In addition, take
the unusual step of spiking double and float to prevent any more
accidental seepage.
We don't support older compilers. Most of the code in these files is
for pre-3.0 gcc, which is at least 15 years obsolete. Move to using
phk's sys/_stdargs.h for all these platforms.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D14323
- Add a new <machine/abi.h> header to hold constants shared between C
and assembly such as CALLFRAME_SZ.
- Add a new STACK_ALIGN constant to <machine/abi.h> and use it to
replace hardcoded constants in the kernel and makecontext(). As a
result of this, ensure the stack pointer on N32 and N64 is 16-byte
aligned for N32 and N64 after exec(), after pthread_create(), and
when sending signals rather than 8-byte aligned.
Reviewed by: jmallett
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D13875
kernel by PHYS_TO_DMAP() as previously present on amd64, arm64, riscv, and
powerpc64. This introduces a new MI macro (PMAP_HAS_DMAP) that can be
evaluated at runtime to determine if the architecture has a direct map;
if it does not (or does) unconditionally and PMAP_HAS_DMAP is either 0 or
1, the compiler can remove the conditional logic.
As part of this, implement PHYS_TO_DMAP() on sparc64 and mips64, which had
similar things but spelled differently. 32-bit MIPS has a partial direct-map
that maps poorly to this concept and is unchanged.
Reviewed by: kib
Suggestions from: marius, alc, kib
Runtime tested on: amd64, powerpc64, powerpc, mips64
The only users of the functions were db_read_bytes() and
db_write_bytes() ddb(4) interfaces. Replace the calls with direct
reads and writes, which are automatically atomic on 64bits and n32.
Note that removed assembler implementation for mips32 is not atomic
anyway.
Reviewed by: jhb
Discussed with: imp
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D13586
and atomic_store_64.
The MD definitions are provided for LP64 only, while mips also uses
them for 32bit and n32. Only define mips variants for 32bit and n32
and change the syntax to match common definitions.
Note that this commit does not fix 32bit asm implementation to follow
new KBI, this will be fixed later. The functions are only used for 8
byte ddb accesses so the known bug does not prevent normal kernel
operations.
Sponsored by: The FreeBSD Foundation
They provide relaxed-ordered atomic access semantic. Due to the
FreeBSD memory model, the operations are syntaxical wrappers around
the volatile accesses. The volatile qualifier is used to ensure that
the access not optimized out and in turn depends on the volatile
semantic as implemented by supported compilers.
The motivation for adding the operation is to help people coming from
other systems or knowing the C11/C++ standards where atomics have
special type and require use of the special access operations. It is
still the case that FreeBSD requires plain load and stores of aligned
integer types to be atomic.
Suggested by: jhb
Reviewed by: alc, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D13534
