Ensure proper handshake to transfer sigfastblock(2) blocking word
ownership from rtld to libthr.
Unfortunately sigfastblock(2) is not enough to stop intercepting
signals in libthr, because critical sections must ensure more than
just signal blocking.
Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773
This allows for rtld to not issue two sigprocmask(2) syscalls for each
symbol binding operation in single-threaded processes. Rtld needs to
block signals as part of locking to ensure signal safety of the bind
process, because signal handlers might need to lazily resolve symbol
references.
As result, number of syscalls issued on startup by simple programs not
using libthr, is typically reduced 2x. For instance, for hello world,
I see:
non-sigfastblock
# (truss ./hello > /dev/null) |& wc -l
63
sigfastblock
# (truss ./hello > /dev/null) |& wc -l
37
Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773
The intent is to provide bsd-specific flags relevant to interpreter
and C runtime. I did not want to reuse AT_FLAGS which is common ELF
auxv entry.
Use bsdflags to report kernel support for sigfastblock(2). This
allows rtld and libthr to safely infer the syscall presence without
SIGSYS. The tunable kern.elf{32,64}.sigfastblock blocks reporting.
Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773
A new syscall sigfastblock(2) is added which registers a uint32_t
variable as containing the count of blocks for signal delivery. Its
content is read by kernel on each syscall entry and on AST processing,
non-zero count of blocks is interpreted same as the signal mask
blocking all signals.
The biggest downside of the feature that I see is that memory
corruption that affects the registered fast sigblock location, would
cause quite strange application misbehavior. For instance, the process
would be immune to ^C (but killable by SIGKILL).
With consumers (rtld and libthr added), benchmarks do not show a
slow-down of the syscalls in micro-measurements, and macro benchmarks
like buildworld do not demonstrate a difference. Part of the reason is
that buildworld time is dominated by compiler, and clang already links
to libthr. On the other hand, small utilities typically used by shell
scripts have the total number of syscalls cut by half.
The syscall is not exported from the stable libc version namespace on
purpose. It is intended to be used only by our C runtime
implementation internals.
Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773
The version that ended upstream was ultimately slightly different than the
version committed here; notably, statvfs() is used but it's redefined
appropriately to statfs() on FreeBSD since we don't provide the fstypename
for the former interface.
This patch introduces processing of the frames
up to 9kB by the mvneta driver. Some versions of
this NIC limit TX checksum offloading, depending
on the frame size, so add appropriate handling
of this feature.
Submitted by: Kornel Duleba
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D23225
The revokex test does not work when the scratch directory is created on NFS.
Given the nature of NFS, it likely can never work without looking like a
security hole since O_SEARCH would rely on the server knowing that the
directory did have +x at the time of open and that it's OK for it to have
been revoked based on POSIX specification for O_SEARCH.
This does mean that O_SEARCH is only partially functional on NFS in general,
but I suspect the execute bit getting revoked in the process is likely not
common.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D23573
To make the PMC tool pmcstat working properly on Hygon platform, add
support for Hygon Dhyana family 18h by using the PMC initialization
code path of AMD family 17h.
Submitted by: Pu Wen <puwen@hygon.cn>
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D23562
Currently the installer will tag geliboot partitions with both BOOT and
GELIBOOT; the former allows the kernel to taste it at boot, while the latter
is what loaders keys off of.
However, it seems reasonable to assume that if a provider's been tagged with
GELIBOOT that the kernel should also take that as a hint to taste/attach at
boot. This would allow us to stop tagging GELIBOOT partitions with BOOT in
bsdinstall, but I'm not sure that there's a compelling reason to do so any
time soon.
Reviewed by: oshogbo
Differential Revision: https://reviews.freebsd.org/D23387
For the moment, supress the operation not supported messages at this level. In
the fullness of time, we will have better error tracking so we can diagnose
issues in the future.
Reviewed by: scottl@
Since AVL already has embedded element counter, use dn_dbufs_count
only for dbufs not counted there (bonus buffers) and just add them.
This removes two atomics per dbuf life cycle.
According to profiler it reduces time spent by dbuf_destroy() inside
bottlenecked dbuf_evict_thread() from 13.36% to 9.20% of the core.
This counter is used only on illumos, so for FreeBSD it was just a
waste of time.
MFC after: 2 weeks
riscv cores.
GFE cores come with standard DTS file that lacks standard 'dmas ='
property, which means xae(4) could not find a DMA controller to use.
The 'dmas' property could not be added to the DTS file because the
ethernet controller and DMA engine parts in Linux are implemented
in a single driver.
Instead of 'dmas' property the standard Xilinx 'axistream-connected'
property is provided, so fallback to use it instead.
Suggested by: James Clarke <jrtc27@jrtc27.com>
Reviewed by: James Clarke <jrtc27@jrtc27.com>
Sponsored by: DARPA, AFRL
in the sysctl block for the driver. mpsutil/mprutil needs this so it can
know how big of a buffer to allocate when requesting the IOCFacts from the
controller. This eliminates the kernel console messages about wrong
allocation sizes.
Reported by: imp
BIO_READ and BIO_WRITE, we've handled this expanded syntax poorly in
drivers when the driver doesn't support a particular command. Do a
sweep and fix that.
Reported by: imp
- Use a constant for the offset instead of a magic number.
- Use an addi instruction that writes to tp directly instead of a mv
that writes the result of a compiler-generated addi.
Reviewed by: mhorne
MFC after: 1 week
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D23521
This was relatively harmless but surprising to see in counters. The
race occurred when rd_seq was read after the goal was updated and we
incorrectly calculated the delta between them.
Reviewed by: rlibby
Differential Revision: https://reviews.freebsd.org/D23464
