When waiters/writer spinner flags are set no new readers can show up unless
they already have a different rw rock read locked. The change in r326195 failed
to take that into account - in presence of new readers it would spin until
they all drain, which would be lead to trouble if e.g. they go off cpu and
can get scheduled because of this thread.
Reported by: pho
This allows modules creating mappings to be loaded post-boot, after SMP has
started. Without this, the TLB1 mappings can become unsynchronized and lead
to kernel page faults when accessed on the alternate CPUs.
MFC after: 3 weeks
This is similar to the TCP case. where a TCP RST segment can be sent.
There is one limitation: When sending an ABORT in response to an incoming
packet, it should be tested if there is no ABORT chunk in the received
packet. Currently, it is only checked if the first chunk is an ABORT
chunk to avoid parsing the whole packet, which could result in a DOS attack.
Thanks to Timo Voelker for helping me to test this patch.
Reviewed by: bcr@ (man page part), ae@ (generic, non-SCTP part)
Differential Revision: https://reviews.freebsd.org/D13239
The documentation on the Saved Process Status Register (SPSR) is a bit
weird; the M[4] bit is documented separately from M[3:0]. The M[4] bit
can be toggled to switch to 32-bit execution mode. This functionality is
orthogonal to M[3:0].
Change the definition of PSR_M_MASK to no longer include M[4]. Add a new
definition, PSR_AARCH32 that can be used to toggle 32-bit independently.
This bit will be used by the cloudabi32 code to force execution of
userspace code in 32-bit mode.
Reviewed by: andrew
Differential Revision: https://reviews.freebsd.org/D13148
For FreeBSD/arm64's cloudabi32 support, I'm going to need a TO_PTR() in
this place. Also use it for all of the other source files, so that the
difference remains as minimal as possible.
MFC after: 2 weeks
The nice thing about ARM64 is that it's pretty elegant to install
separate trap/exception handlers for 32-bit and 64-bit processes. That
said, for all other architectures (e.g., i386 on amd64) we always let
32-bit counterparts go through the regular system call codepath. Let's
do the same on ARM64.
Reviewed by: andrew
Differential Revision: https://reviews.freebsd.org/D13146
S_vmtotal:
Use unsigned format to print unsigned memory counters from struct
vmtotal.
Remove unneeded cast, style locals declarations.
S_efi_map:
Make printing of the memory regions descriptions less MD by
using uintmax_t formats.
Noted by and discussed with: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
PowerPC kernels in r6 is actually metadata from loader(8) or gibberish
left in r6, which is not required to be anything under the
PAPR/ePAPR/CHRP/OF standards, by another boot loader.
Note that, as a result, systems need a new boot loader to boot PPC kernels
after this revision without ending up at a mountroot prompt. New boot
loaders are backwards compatible and can boot older kernels.
Reviewed by: jhibbits
MFC after: 2 months
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
just set it to a large default value (and inherit any previously existing
value), hoping it never turns over. Instead, silently allow spurious
one-shots from rollovers.
MFC after: 10 days
and such from ending on the wrong CPU on SMP systems. It would be good to
have this be more generic somehow as POWER9s appear, but PPC does not
have features bits, unfortunately.
MFC after: 3 weeks
is set and the right thing to do may be platform-dependent (it requires
firmware on PowerNV, for instance). Make it a new platform method called
platform_smp_timebase_sync().
MFC after: 3 weeks
This has the same effects on DDB working as -mcall=aixdesc, but also is
supported by clang and marginally improves kernel performance.
MFC after: 2 weeks
sleepq is only locked if the curhtread is the last reader. By the time
the lock gets acquired new ones could have arrived. The previous code
would unlock and loop back. This results spurious relocking of sleepq.
This is a step towards xadd-based unlock routine.
In order to go to sleep threads set waiter flags, but that can spuriously
fail e.g. when a new reader arrives. Instead of unlocking everything and
looping back, re-evaluate the new state while still holding the lock necessary
to go to sleep.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Originally a patch by Mark Millard, augmented with information from work
done on NetBSD by jmcneill@.
Submitted by: Mark Millard (markmi@dsl-only.net)
Reviewed by: emaste, manu
Approved by: emaste (mentor)
Differential Revision: https://reviews.freebsd.org/D13240
The r-ccu on the a83t differs from the others only by what it names the
ar100 parents. Export the _CCU macros (now converted to an enu) so that
ccu_sun8i_r can differentiate between a83t r-ccu and the others, then add
the compat string for the a83t r-ccu.
Reviewed by: manu
Approved by: emaste (mentor, implicit)
Differential Revision: https://reviews.freebsd.org/D13206