The code would unconditionally lock the vnode to audit or call the
mac hoook, even if neither want to do anything. Pre-check the state
to avoid locking in the common case of nothing to do.
Note this code should not be normally executed anyway as vnodes are
always return ready. However, poll1/2 from will-it-scale use regular
files for benchmarking, presumably to focus on the interface itself
as the vnode handler is not supposed to do almost anything.
This in particular fixes poll2 which passes 128 fds.
$ ./poll2_processes -s 10
before: 134411
after: 271572
It keeps recalculated way more often than it is needed.
Provide a routine (fdlastfile) to get it if necessary.
Consumers may be better off with a bitmap iterator instead.
Previously it would check 4, 3, 2, 1 lists. In practice by the time
it is getting called all lists have some elements and consequently
this does not result in new evictions.
Nonetheless, the code is clearer.
Tested by: pho
.. and stuff if into the unused target vnode field
This gets rid of concurrent nc_flag modifications racing with the
shrinker and consequently fixes a bug where such a change could have
been missed when cache_ncp_invalidate was being issued..
Reported by: zeising
Tested by: pho, zeising
Fixes: r362828 ("cache: lockless forward lookup with smr")
We don't expect to fail acquiring the reference unless running into a corner
case. Just in case ensure forward progress by taking the lock.
Reviewed by: kib, markj
Differential Revision: https://reviews.freebsd.org/D25616
The kernel would unlock already unlocked mutex if the buffer got filled up
before the mount list ended.
Reported by: pho
Fixes: r363069 ("vfs: depessimize getfsstat when only the count is requested")
Lack of SHM_GROW_ON_WRITE is actively breaking Python's memfd_create tests,
so go ahead and implement it. A future change will make memfd_create always
set SHM_GROW_ON_WRITE, to match Linux behavior and unbreak Python's tests
on -CURRENT.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D25502
While this behaviour is harmless, it is really just an artifact of the
fact that the msgctl(2) implementation uses a user-visible structure as
part of the internal implementation, so it is not deliberate and these
pointers are not useful to userspace. Thus, NULL them out before
copying out, and remove references to them from the manual page.
Reported by: Jeffball <jeffball@grimm-co.com>
Reviewed by: emaste, kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25600
These system calls already perform validation of their parameters when
called in capability mode, identical to cpuset_(get|set)affinity().
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
cpuset_(get|set)(affinity|domain)(2) permit a get or set of the calling
thread or process' CPU and domain set in capability mode, but only when
the thread or process ID is specified as -1. Extend this to cover the
case where the ID actually matches the caller's TID or PID, since some
code, such as our pthread_attr_get_np() implementation, always provides
an explicit ID.
It was not and still is not permitted to access CPU and domain sets for
other threads in the same process when the process is in capability
mode. This might change in the future.
Submitted by: Greg V <greg@unrelenting.technology> (original version)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D25552
Add a more compact display format for kern.tty_info_kstacks inspired by
procstat -kk. Set it as a default one.
# sysctl kern.tty_info_kstacks=1
kern.tty_info_kstacks: 0 -> 1
# sleep 2
^T
load: 0.17 cmd: sleep 623 [nanslp] 0.72r 0.00u 0.00s 0% 2124k
#0 0xffffffff80c4443e at mi_switch+0xbe
#1 0xffffffff80c98044 at sleepq_catch_signals+0x494
#2 0xffffffff80c982c2 at sleepq_timedwait_sig+0x12
#3 0xffffffff80c43af3 at _sleep+0x193
#4 0xffffffff80c50e31 at kern_clock_nanosleep+0x1a1
#5 0xffffffff80c5119b at sys_nanosleep+0x3b
#6 0xffffffff810ffc69 at amd64_syscall+0x119
#7 0xffffffff810d5520 at fast_syscall_common+0x101
sleep: about 1 second(s) left out of the original 2
^C
# sysctl kern.tty_info_kstacks=2
kern.tty_info_kstacks: 1 -> 2
# sleep 2
^T
load: 0.24 cmd: sleep 625 [nanslp] 0.81r 0.00u 0.00s 0% 2124k
mi_switch+0xbe sleepq_catch_signals+0x494 sleepq_timedwait_sig+0x12
sleep+0x193 kern_clock_nanosleep+0x1a1 sys_nanosleep+0x3b
amd64_syscall+0x119 fast_syscall_common+0x101
sleep: about 1 second(s) left out of the original 2
^C
Suggested by: avg
Reviewed by: mjg
Relnotes: yes
Sponsored by: Mysterious Code Ltd.
Differential Revision: https://reviews.freebsd.org/D25487
Otherwise the same checks are duplicated across four different system
call implementations, cpuset_(get|set)(affinity|domain)(). No
functional change intended.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
On architectures that use RELA relocations it is safe to rerun the ifunc
resolvers on after all CPUs have started, but while they are sill parked.
On arm64 with big.LITTLE this is needed as some SoCs have shipped with
different ID register values the big and little clusters meaning we were
unable to rely on the register values from the boot CPU.
Add support for rerunning the resolvers on arm64 and amd64 as these are
both RELA using architectures.
Reviewed by: kib
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D25455
They trigger for some people, the bug is not obvious, there are no takers
for fixing it, the issue already had to be there for years beforehand and
is low priority.
Rather than unlocking and returning we can just perform the needed action
only when the interrupt source is valid and reuse the unlock in both the
valid irq and invalid irq cases.
Sponsored by: Innovate UK
This eliminates the need to take bucket locks in the common case.
Concurrent lookup utilizng the same vnodes is still bottlenecked on referencing
and locking path components, this will be taken care of separately.
Reviewed by: kib
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D23913
vget_prep_smr and vhold_smr can be used to ref a vnode while within vfs_smr
section, allowing consumers to get away without locking.
See vhold_smr and vdropl for comments explaining caveats.
Reviewed by: kib
Testec by: pho
Differential Revision: https://reviews.freebsd.org/D23913
LIST_FOREACH_SAFE() is not safe in the presence
of other threads removing list entries when a
mutex is released.
This is not in the critical path, so just restart
the scan each time we drop the lock, rather than
using a marker.
Reviewed by: jhb, markj
Sponsored by: Netflix
In addition to reducing lines of code, this also ensures that the full
allocation is always zeroed avoiding possible bugs with incorrect
lengths passed to explicit_bzero().
Suggested by: cem
Reviewed by: cem, delphij
Approved by: csprng (cem)
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D25435
All vm_object_page_remove() callers, except
linux_invalidate_mapping_pages() in the LinuxKPI, free swap space when
removing a range of pages from an object. The LinuxKPI case appears to
be an unintentional omission that could result in leaked swap blocks, so
unconditionally free swap space in vm_object_page_remove() to protect
against similar bugs in the future.
Reviewed by: alc, kib
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25329
Adding `kern.features.witness` helps expose whether or not the kernel has
`options WITNESS` enabled, so the `feature_present(3)` API can be used
to query whether or not witness(9) is built into the kernel.
This support is helpful with userspace applications (generally speaking,
tests), as it can be queried to determine whether or not tests related
to WITNESS should be run.
MFC after: 1 week
Reviewed by: cem, darrick.freebsd_gmail.com
Differential Revision: https://reviews.freebsd.org/D25302
Sponsored by: DellEMC Isilon
For software like PostgreSQL and SQLite that sometimes reads sequentially
while also writing sequentially some distance behind with interleaved
syscalls on the same fd, performance is better on UFS if we do
sequential access heuristics separately for reads and writes.
Patch originally by Andrew Gierth in 2008, updated and proposed by me with
his permission.
Reviewed by: mjg, kib, tmunro
Approved by: mjg (mentor)
Obtained from: Andrew Gierth <andrew@tao11.riddles.org.uk>
Differential Revision: https://reviews.freebsd.org/D25024
It turns out relocating the symbol table itself can cause issues, like fbt
crashing because it applies the offsets to the kernel twice.
This had been previously brought up in rS333447 when the stoffs hack was
added, but I had been unaware of this and reimplemented symtab relocation.
Instead of relocating the symbol table, keep track of the relocation base
in ddb, so the ddb symbols behave like the kernel linker-provided symbols.
This is intended to be NFC on platforms other than PowerPC, which do not
use fully relocatable kernels. (The relbase will always be 0)
* Remove the rest of the stoffs hack.
* Remove my half-baked displace_symbol_table() function.
* Extend ddb initialization to cope with having a relocation offset on the
kernel symbol table.
* Fix my kernel-as-initrd hack to work with booke64 by using a temporary
mapping to access the data.
* Fix another instance of __powerpc__ that is actually RELOCATABLE_KERNEL.
* Change the behavior or X_db_symbol_values to apply the relocation base
when updating valp, to match link_elf_symbol_values() behavior.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D25223
hw.bus.info was added in r68522 as a node, but there was never anything
connected "behind" it. Its only purpose is to return a struct u_businfo.
The only in-base consumer are devinfo(3)/devinfo(8).
Rewrite the handler as SYSCTL_PROC and mark it as MPSAFE and read-only
as there never was a writable path.
Reviewed by: kib
Approved by: kib (mentor)
Sponsored by: Mysterious Code Ltd.
Differential Revision: https://reviews.freebsd.org/D25321
This is in preparation for enabling a loadable SCTP stack. Analogous to
IPSEC/IPSEC_SUPPORT, the SCTP_SUPPORT kernel option must be configured
in order to support a loadable SCTP implementation.
Discussed with: tuexen
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
There may be some version of mountd out there that does not supply a default
security flavor when none is given for an export.
Set the default security flavor in vfs_export if none is given, and remove the
workaround for oexport compat.
Reported by: npn
Reviewed by: rmacklem
Approved by: mav (mentor)
MFC after: 3 days
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D25300
When doing secure boot, loader wants to export loader.ve.hashed
the value of which typically exceeds KENV_MVALLEN.
Replace use of KENV_MVALLEN with tunable kenv_mvallen.
Add getenv_string_buffer() for the case where a stack buffer cannot be
created and use uma_zone_t kenv_zone for suitably sized buffers.
Reviewed by: stevek, kevans
Obtained from: Abhishek Kulkarni <abkulkarni@juniper.net>
MFC after: 1 week
Sponsored by: Juniper Networks
Differential Revision: https://reviews.freebsd.org//D25259