With compilers making increasing use of vector instructions the
performance benefit of lazily switching FPU state is no longer a
desirable tradeoff. Linux switched to eager FPU context switch some
time ago, and the idea was floated on the FreeBSD-current mailing list
some years ago[1].
Enable eager FPU context switch by default on amd64, with a tunable/sysctl
available to turn it back off.
[1] https://lists.freebsd.org/pipermail/freebsd-current/2015-March/055198.html
Reviewed by: jhb
Tested by: pho
Sponsored by: The FreeBSD Foundation
Most kernel memory that is allocated after boot does not need to be
executable. There are a few exceptions. For example, kernel modules
do need executable memory, but they don't use UMA or malloc(9). The
BPF JIT compiler also needs executable memory and did use malloc(9)
until r317072.
(Note that a side effect of r316767 was that the "small allocation"
path in UMA on amd64 already returned non-executable memory. This
meant that some calls to malloc(9) or the UMA zone(9) allocator could
return executable memory, while others could return non-executable
memory. This change makes the behavior consistent.)
This change makes malloc(9) return non-executable memory unless the new
M_EXEC flag is specified. After this change, the UMA zone(9) allocator
will always return non-executable memory, and a KASSERT will catch
attempts to use the M_EXEC flag to allocate executable memory using
uma_zalloc() or its variants.
Allocations that do need executable memory have various choices. They
may use the M_EXEC flag to malloc(9), or they may use a different VM
interfact to obtain executable pages.
Now that malloc(9) again allows executable allocations, this change also
reverts most of r317072.
PR: 228927
Reviewed by: alc, kib, markj, jhb (previous version)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D15691
Allow one to implement a 'car limit' for
bioq_disksort. debug.bioq_batchsize sets the size of car limit. Every
time we queue that many requests, we start over so that we limit the
latency for requests when the software queue depths are large. A value
of '0', the default, means to revert to the old behavior.
Sponsored by: Netflix
to call into the firmware in a similar way to the existing PSCI, and used
PSCI to detect when SMCCC is enabled.
There is a function ID space we can use. Currently we only support 3
functions in the ARM Architecture Calls region, however it is expected we
will expend these in the future.
Sponsored by: DARPA, AFRL
Due to a copy/paste error in r168688, ARG_TERMID_ADDR has the same
definition as ARG_SADDRUNIX. Fix it.
The header change, while publicly visible, is guarded by #ifdef KERNEL, and
I can't find any kmod ports that use it. So I'm not bumping
__FreeBSD_version.
PR: 228820
Submitted by: aniketp
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D15702
the old encodings for the lower 16 and 32 bits and only using the
higher 32 bits for unusually large major and minor numbers. This
change breaks compatibility with the previous encoding (which was only
used in -current).
Fix truncation to (essentially) 16-bit dev_t in newnfs v3.
Any encoding of device numbers gives an ABI, so it can't be changed
without translations for compatibility. Extra bits give the much
larger complication that the translations need to compress into fewer
bits. Fortunately, more than 32 bits are rarely needed, so
compression is rarely needed except for 16-bit linux dev_t where it
was always needed but never done.
The previous encoding moved the major number into the top 32 bits.
Almost no translation code handled this, so the major number was blindly
truncated away in most 32-bit encodings. E.g., for ffs, mknod(8) with
major = 1 and minor = 2 gave dev_t = 0x10000002; ffs cannot represent
this and blindly truncated it to 2. But if this mknod was run on any
released version of FreeBSD, it gives dev_t = 0x102. ffs can represent
this, but in the previous encoding it was not decoded, giving major = 0,
minor = 0x102.
The presence of bugs was most obvious for exporting dev_t's from an
old system to -current, since bugs in newnfs augment them. I fixed
oldnfs to support 32-bit dev_t in 1996 (r16634), but this regressed
to 16-bit dev_t in newnfs, first to the old 16-bit encoding and then
further in -current. E.g., old ad0 with major = 234, minor = 0x10002
had the correct (major, minor) number on the wire, but newnfs truncated
this to (234, 2) and then the previous encoding shifted the major
number into oblivion as seen by ffs or old applications.
I first tried to fix this by translating on every ABI/API boundary, but
there are too many boundaries and too many sloppy translations by blind
truncation. So use the old encoding for the low 32 bits so that sloppy
translations work no worse than before provided the high 32 bits are
not set. Add some error checking for when bits are lost. Keep not
doing any error checking for translations for almost everything in
compat/linux.
compat/freebsd32/freebsd32_misc.c:
Optionally check for losing bits after possibly-truncating assignments as
before.
compat/linux/linux_stats.c:
Depend on the representation being compatible with Linux's (or just with
itself for local use) and spell some of the translations as assignments in
a macro that hides the details.
fs/nfsclient/nfs_clcomsubs.c:
Essentially the same fix as in 1996, except there is now no possible
truncation in makedev() itself. Also fix nearby style bugs.
kern/vfs_syscalls.c:
As for freebsd32. Also update the sysctl description to include file
numbers, and change it to describe device ids as device numbers.
sys/types.h:
Use inline functions (wrapped by macros) since the expressions are now
a bit too complicated for plain macros. Describe the encoding and
some of the reasons for it. 16-bit compatibility didn't leave many
reasonable choices for the 32-bit encoding, and 32-bit compatibility
doesn't leave many reasonable choices for the 64-bit encoding. My
choice is to put the 8 new minor bits in the low 8 bits of the top 32
bits. This minimizes discontiguities.
Reviewed by: kib (except for rewrite of the comment in linux_stats.c)
allocation, I could identify that actually we use this pointer on pci_emul.c as
well as on vga.c source file.
I have reworked the logic here to make it more readable and also add a warn to
explicit show the function where the memory allocation error could happen,
also sort headers.
Also CID 1194192 was marked as "Intentional".
Obtained from: TrueOS
MFC after: 4 weeks.
Sponsored by: iXsystems Inc.
- remove __pure annotations I added earlier for some functions. One
writes to the the arguments as "out" pointers. The
other reads from an array, which while const within the function might
be mutated externally.
- total_change is modified to be at 1, if previously 0, so no if check
is needed.
of needed interface when many gre interfaces are present.
Remove rmlock from gre_softc, use epoch(9) and CK_LIST instead.
Move more AF-related code into AF-related locations. Use hash table to
speedup lookup of needed softc.
This fixes the race when first core sets up the pagetables, while
secondary cores do translating the address of __riscv_boot_ap.
This now allows us to smpboot in QEMU with 8 cores just fine.
Sponsored by: DARPA, AFRL
Continue my parade on introspection tools by fixing:
- failed to check for null after reallocf
- avoid the comma operator
- mark usage as dead
- correct size of len
of 64-bit dev_t's (but not ones involving dev_t's).
st_size was supposed to be clamped in cvtstat() and linux's copy_stat(),
but the clamping code wasn't aware that st_size is signed, and also had
an obfuscated off-by-1 value for the unsigned limit, so its effect was
to produce a bizarre negative size instead of clamping.
Change freebsd32's copy_ostat() to be no worse than cvtstat(). It was
missing clamping and bzero()ing of padding.
Reviewed by: kib (except a final fix of the clamp to the signed maximum)
Some casts from pointers to uint64_t and back in lio_main.c cause base
gcc on i386 to warn "cast from pointer to integer of different size",
and vice versa. Add additional casts to uintptr_t to suppress these.
Reviewed by: sbruno
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D15754
When hash table lookups are not serialized with in_pcbfree it will be
possible for callers to find an inpcb that has been marked free. We
need to check for this and return NULL.
- initialize all maybe uninitialized vars with bogus values. This shuts
up the compiler, and causes crashes if it changes later.
- mark noreturn as noreturn
- removed unused macro
- handle x_procstate as runtime rather than pre-processor
- avoid using void functions in condtionals
Tested with clang, gcc 7, gcc 9
without this and running vnets with a TCP stack that uses
some of the features is a recipe for panic (without this commit).
Reported by: Larry Rosenman
Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D15757
