domains can be done by the _domain() API variants. UMA also supports a
first-touch policy via the NUMA zone flag.
The slab layer is now segregated by VM domains and is precise. It handles
iteration for round-robin directly. The per-cpu cache layer remains
a mix of domains according to where memory is allocated and freed. Well
behaved clients can achieve perfect locality with no performance penalty.
The direct domain allocation functions have to visit the slab layer and
so require per-zone locks which come at some expense.
Reviewed by: Attilio (a slightly older version)
Tested by: pho
Sponsored by: Netflix, Dell/EMC Isilon
reservations by giving each memory domain its own KVA space in vmem that
is naturally aligned on superpage boundaries.
Reviewed by: alc, markj, kib (some objections)
Sponsored by: Netflix, Dell/EMC Isilon
Tested by; pho
Differential Revision: https://reviews.freebsd.org/D13289
userspace to control NUMA policy administratively and programmatically.
Implement domainset based iterators in the page layer.
Remove the now legacy numa_* syscalls.
Cleanup some header polution created by having seq.h in proc.h.
Reviewed by: markj, kib
Discussed with: alc
Tested by: pho
Sponsored by: Netflix, Dell/EMC Isilon
Differential Revision: https://reviews.freebsd.org/D13403
Skip vfs_refcount_release_if_not_last if the interlock is held and just
go straight to refcount_release.
While here do cosmetic rearrangement of _vhold to better show it contains
equivalent behaviour.
pru_peeraddr().
This is already true when called via kern_getsockname() and
kern_getpeername(). This patch sets it also, when they arecalled
via soo_fill_kinfo(). This is necessary, since the corresponding
functions for SCTP require the vnet to be set. Without this,
if a process having an wildcard bound SCTP socket is
terminated and a core is written, the kernel panics.
Reviewed by: bz
Differential Revision: https://reviews.freebsd.org/D13652
Additionally, move the overflow check logic out to WOULD_OVERFLOW() for
consumers to have a common means of testing for overflowing allocations.
WOULD_OVERFLOW() should be a secondary check -- on 64-bit platforms, just
because an allocation won't overflow size_t does not mean it is a sane size
to request. Callers should be imposing reasonable allocation limits far,
far, below overflow.
Discussed with: emaste, jhb, kp
Sponsored by: Dell EMC Isilon
Previously the AIO subsystem would save a snapshot of the currently
configured per-process limits the first time a process used AIO. The
process would continue to use the snapshotted limits ignoring any
changes to the global limits during the rest of its lifetime. This
change removes the snapshotted values and changes the AIO code to
always check the global values which can be toggled at runtime.
This means an administrator can now change the effective limits of
existing processes. This is more consistent with how other limits
configured via sysctl work in FreeBSD.
Reviewed by: asomers, kib
MFC after: 2 weeks
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D13819
- If aio_qphysio() returns a non-zero error code, fail the request rather
than queueing it to the AIO kproc pool to be retried via the slow path.
Currently this means that if vm_fault_quick_hold_pages() reports an
error, EFAULT is returned from the fast-path rather than retrying the
request in the slow path where it will still fail with EFAULT.
- If aio_qphysio() wishes to use the fast path for a device that doesn't
support unmapped I/O but there are already the maximum number of
such requests in flight, fail with EAGAIN as we do for other AIO
resource limits rather than queueing the request to the AIO kproc pool.
- Move the opcode check for aio_qphysio() out of the caller and into
aio_qphysio() to simplify some logic and remove two goto's while here.
It also uses a whitelist (only supported for LIO_READ / LIO_WRITE)
rather than a blacklist (skipped for LIO_SYNC).
PR: 217261
Submitted by: jkim (an earlier version)
MFC after: 2 weeks
Sponsored by: Chelsio Communications
Specifically, in aio_queue_file() the code was doing this:
if (opcode == LIO_SYNC) {
...
}
switch (opcode) {
...
case LIO_SYNC:
...
}
This moves the body of the if statement into the LIO_SYNC case of the
switch statement.
MFC after: 2 weeks
Sponsored by: Chelsio Communications
We currently use a set of subroutines in kern_gzio.c to perform
compression of user and kernel core dumps. In the interest of adding
support for other compression algorithms (zstd) in this role without
complicating the API consumers, add a simple compressor API which can be
used to select an algorithm.
Also change the (non-default) GZIO kernel option to not enable
compressed user cores by default. It's not clear that such a default
would be desirable with support for multiple algorithms implemented,
and it's inconsistent in that it isn't applied to kernel dumps.
Reviewed by: cem
Differential Revision: https://reviews.freebsd.org/D13632
Similar to calloc() the mallocarray() function checks for integer
overflows before allocating memory.
It does not zero memory, unless the M_ZERO flag is set.
Reviewed by: pfg, vangyzen (previous version), imp (previous version)
Obtained from: OpenBSD
Differential Revision: https://reviews.freebsd.org/D13766
This avoids re-reading a variable after it has been updated via an
atomic op. It is just a cosmetic cleanup as the read value was only
used to control a diagnostic printf that should rarely occur (if ever).
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D13768
For the pathname reported in kinfo_vmentry structures (kve_path), the
sysctl handlers walk the object chain to find the bottom-most VM object.
This permits a COW mapping of a file with dirty pages to report the
pathname of the originally mapped file. Do the same for the object
offset (kve_offset) computing a cumulative offset during the same object
walk so that the reported offset is relative to the reported pathname.
Note that ptrace(PT_VM_ENTRY) already returns a cumulative offset
rather than the raw offset of the VM map entry.
Note also that this does not affect procstat -v output (even structured
output) since that output does not include the kve_offset field.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D13767
Enable the hardclock-based watchdog previously conditional on the
SW_WATCHDOG option whenever hardware watchdogs are not found, and
watchdogd attempts to enable the watchdog. The SW_WATCHDOG option
still causes the sofware watchdog to be enabled even if there is a
hardware watchdog. This does not change the other software-based
watchdog enabled by the --softtimeout option to watchdogd.
Note that the code to reprime the watchdog during kernel core dumps is
no longer conditional on SW_WATCHDOG. I think this was previously a bug.
Reviewed by: imp alfred bjk
MFC after: 1 week
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D13713
are places where the "main thread" of the booting kernel (either the
thread which later becomes swapper or the thread which later becomes
init) has to stop and wait for action to take place in another thread
before continuing.
There are currently three such holds:
1. The intr_config_hooks SYSINIT waits for hooks registered via the
config_intrhook_establish function; this allows (typically) devices
which need interrupts enabled to complete their initialization to do
so before root is mounted.
2. The g_waitidle function waits for the GEOM event queue to be empty;
this ensures that all of the disks which have been attached have been
tasted before we attempt to mount root.
3. The vfs_mountroot_wait function (in addition to calling g_waitidle)
waits for holds registered via root_mount_hold; among other things, this
is used by the USB subsystem to ensure that we don't fail to mount root
if it's located on a USB disk which takes a while to probe.
METHOD and STATICMETHOD declarations; that code will be inserted
into the dispatch function before and after the method call.
Use this functionality and the TSLOG framework to record DEVICE_ATTACH
and DEVICE_PROBE entry/exit timestamps.
independent functions with important roles in the early boot process:
mi_startup (with the "exit" recorded when it becomes swapper),
start_init (with the "exit" recorded when the thread is about to
"return" into the newly created init process), vfs_mountroot, and
vfs_mountroot_wait.
This is a very primitive system, intended for use in measuring performance
during the early system boot, before more sophisticated tools like DTrace
or infrastructure like kernel memory allocation and mutexes are available.
Because this code records pointers to strings rather than copying strings
(in order to keep the memory usage more manageable), if a kernel module is
unloaded after logging an event, Bad Things can happen. Users are advised
to not do that.
Since cycle counts from the early kernel boot are used as an initial entropy
source, publishing this information to userland could result in inadequate
entropy being kept private to the kernel RNG. Users are advised to not
enable this on systems with untrusted users.
Discussed on: freebsd-current
Both files originated in NetBSD:
sysv_ipc.c CVS 1.9:
Most of their changes don't apply to us as we already have similar
changes. This is a better reference for future merges.
sysv_shm.c CVS 1.39:
Most of their changes don't apply to our code but interestingly this
revision merged our changes and is a better point for reference.
Move the VCS tags to the position recommended in our committers guide
(section 8),
No functional change.
In both rw and sx locks we always go to sleep if the lock owner is not
running.
We do spin for some time if the lock is read-locked.
However, if we decide to go to sleep due to the lock owner being off cpu
and after sleepq/turnstile gets acquired the lock is read-locked, we should
fallback to the aforementioned wait.
Since this function is effectively slow path, if we get here the lock is most
likely already taken in which case it is cheaper to not blindly attempt the
atomic op.
While here move hwpmc probe out of the loop to match other primitives.
vmmap_skip_res_cnt control check inside it.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D13595
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
restart_cpus() worked well enough by accident. Before this set of fixes,
resume_cpus() used the same cpuset (started_cpus, meaning CPUs directed to
restart) as restart_cpus(). resume_cpus() waited for the wrong cpuset
(stopped_cpus) to become empty, but since mixtures of stopped and suspended
CPUs are not close to working, stopped_cpus must be empty when resuming so
the wait is null -- restart_cpus just allows the other CPUs to restart and
returns without waiting.
Fix resume_cpus() to wait on a non-wrong cpuset for the ACPI case, and
add further kludges to try to keep it working for the XEN case. It
was only used for XEN. It waited on suspended_cpus. This works for
XEN. However, for ACPI, resuming is a 2-step process. ACPI has already
woken up the other CPUs and removed them from suspended_cpus. This
fix records the move by putting them in a new cpuset resuming_cpus.
Waiting on suspended_cpus would give the same null wait as waiting on
stopped_cpus. Wait on resuming_cpus instead.
Add a cpuset toresume_cpus to map the CPUs being told to resume to keep
this separate from the cpuset started_cpus for mapping the CPUs being told
to restart. Mixtures of stopped and suspended/resuming CPUs are still far
from working. Describe new and some old cpusets in comments.
Add further kludges to cpususpend_handler() to try to avoid breaking it
for XEN. XEN doesn't use resumectx(), so it doesn't use the second
return path for savectx(), and it goes from the suspended state directly
to the restarted state, while ACPI resume goes through the resuming state.
Enter the resuming state early for all cases so that resume_cpus can test
for being in this state and not have to worry about the intermediate
!suspended state for ACPI only.
Reviewed by: kib
On the one hand, FIFOs should respect other variables not supported by
the fifofs vnode operation (such as _PC_NAME_MAX, _PC_LINK_MAX, etc.).
These values are fs-specific and must come from a fs-specific method.
On the other hand, filesystems that support FIFOs are required to
support _PC_PIPE_BUF on directory vnodes that can contain FIFOs.
Given this latter requirement, once the fs-specific VOP_PATHCONF
method supports _PC_PIPE_BUF for directories, it is also suitable for
FIFOs permitting a single VOP_PATHCONF method to be used for both
FIFOs and non-FIFOs.
To that end, retire all of the FIFO-specific pathconf methods from
filesystems and change FIFO-specific vnode operation switches to use
the existing fs-specific VOP_PATHCONF method. For fifofs, set it's
VOP_PATHCONF to VOP_PANIC since it should no longer be used.
While here, move _PC_PIPE_BUF handling out of vop_stdpathconf() so that
only filesystems supporting FIFOs will report a value. In addition,
only report a valid _PC_PIPE_BUF for directories and FIFOs.
Discussed with: bde
Reviewed by: kib (part of a larger patch)
MFC after: 1 month
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D12572
Having all filesystems fall through to default values isn't always correct
and these values can vary for different filesystem implementations. Most
of these changes just use the existing default values with a few exceptions:
- Don't report CHOWN_RESTRICTED for ZFS since it doesn't do the exact
permissions check this claims for chown().
- Use NANDFS_NAME_LEN for NAME_MAX for nandfs.
- Don't report a LINK_MAX of 0 on smbfs. Now fail with EINVAL to
indicate hard links aren't supported.
Requested by: bde (though perhaps not this exact implementation)
Reviewed by: kib (earlier version)
MFC after: 1 month
Sponsored by: Chelsio Communications
The method handles NAME_MAX and LINK_MAX explicitly. For all other
pathconf variables, the method passes the request down to the underlying
file descriptor. This requires splitting a kern_fpathconf() syscallsubr
routine out of sys_fpathconf(). Also, to avoid lock order reversals with
vnode locks, the fdescfs vnode is unlocked around the call to
kern_fpathconf(), but with the usecount of the vnode bumped.
MFC after: 1 month
Sponsored by: Chelsio Communications
In this case volatile qualifiers enusre that a compiler does not
optimize the accesses out.
Reviewed by: alc, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D13534
This variable should be pure MI except possibly for reading it in MD
dump routines. Its initialization was pure MD in 4.4BSD, but FreeBSD
changed this in r36441 in 1998. There were many imperfections in
r36441. This commit fixes only a small one, to simplify fixing the
others 1 arch at a time. (r47678 added support for
special/early/multiple message buffer initialization which I want in
a more general form, but this was too fragile to use because hacking
on the msgbufp global corrupted it, and was only used for 5 hours in
-current...)
A correct destruction is important for WITNESS(4) and LOCK_PROFILING(9).
Submitted by: Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after: 1 week
started, but also by the turnstiles to mark a thread as runnable for
all locks, for instance sleepqueues do:
setrunnable()->sched_wakeup()->sched_add()
In r326218 code was added to allow booting from non-zero CPU numbers
by setting the ts_cpu field inside the ULE scheduler's sched_add()
function. This had an undesired side-effect that prior sched_pin() and
sched_bind() calls got disregarded. This patch fixes the
initialization of the ts_cpu field for the ULE scheduler to only
happen once when the initial thread is constructed during system
init. Forking will then later on ensure that a valid ts_cpu value gets
copied to all children.
Reviewed by: jhb, kib
Discussed with: nwhitehorn
MFC after: 1 month
Differential revision: https://reviews.freebsd.org/D13298
Sponsored by: Mellanox Technologies
The arena argument to kmem_*() is now only used in an assert. A follow-up
commit will remove the argument altogether before we freeze the API for the
next release.
This replaces the hard limit on kmem size with a soft limit imposed by UMA. When
the soft limit is exceeded we periodically wakeup the UMA reclaim thread to
attempt to shrink KVA. On 32bit architectures this should behave much more
gracefully as we exhaust KVA. On 64bit the limits are likely never hit.
Reviewed by: markj, kib (some objections)
Discussed with: alc
Tested by: pho
Sponsored by: Netflix / Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D13187
is up to the caller to check for a NULL return value. The assert was meant
to catch buggy code that did not check the return value. Some code, however,
was smart and used the return value to see if a CPU existed, which this
broke.
Requested by: jhb@
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified 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.
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
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.
- Add a new KTR_STRUCT_ARRAY ktrace record type which dumps an array of
structures.
The structure name in the record payload is preceded by a size_t
containing the size of the individual structures. Use this to
replace the previous code that dumped the kevent arrays dumped for
kevent(). kdump is now able to decode the kevent structures rather
than dumping their contents via a hexdump.
One change from before is that the 'changes' and 'events' arrays are
not marked with separate 'read' and 'write' annotations in kdump
output. Instead, the first array is the 'changes' array, and the
second array (only present if kevent doesn't fail with an error) is
the 'events' array. For kevent(), empty arrays are denoted by an
entry with an array containing zero entries rather than no record.
- Move kevent decoding tables from truss to libsysdecode.
This adds three new functions to decode members of struct kevent:
sysdecode_kevent_filter, sysdecode_kevent_flags, and
sysdecode_kevent_fflags.
kdump uses these helper functions to pretty-print kevent fields.
- Move structure definitions for freebsd11 and freebsd32 kevent
structures to <sys/event.h> so that they can be shared with userland.
The 32-bit structures are only exposed if _WANT_KEVENT32 is defined.
The freebsd11 structures are only exposed if _WANT_FREEBSD11_KEVENT is
defined. The 32-bit freebsd11 structure requires both.
- Decode freebsd11 kevent structures in truss for the compat11.kevent()
system call.
- Log 32-bit kevent structures via ktrace for 32-bit compat kevent()
system calls.
- While here, constify the 'void *data' argument to ktrstruct().
Reviewed by: kib (earlier version)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D12470
Upon successful completion, the execve() system call invokes
exec_setregs() to initialize the registers of the initial thread of the
newly executed process. What is weird is that when execve() returns, it
still goes through the normal system call return path, clobbering the
registers with the system call's return value (td->td_retval).
Though this doesn't seem to be problematic for x86 most of the times (as
the value of eax/rax doesn't matter upon startup), this can be pretty
frustrating for architectures where function argument and return
registers overlap (e.g., ARM). On these systems, exec_setregs() also
needs to initialize td_retval.
Even worse are architectures where cpu_set_syscall_retval() sets
registers to values not derived from td_retval. On these architectures,
there is no way cpu_set_syscall_retval() can set registers to the way it
wants them to be upon the start of execution.
To get rid of this madness, let sys_execve() return EJUSTRETURN. This
will cause cpu_set_syscall_retval() to leave registers intact. This
makes process execution easier to understand. It also eliminates the
difference between execution of the initial process and successive ones.
The initial call to sys_execve() is not performed through a system call
context.
Reviewed by: kib, jhibbits
Differential Revision: https://reviews.freebsd.org/D13180
An assertion was modified to use the found value, but it was not updated to
handle a race where blocked threads appear after the entrance to the func.
Move the assertion down to the area protected with sleepq lock where the
lock is read anyway. This does not affect coverage of the assertion and
is consistent with what rw locks are doing.
Reported by: Shawn Webb
The pair is of use only in debug or LOCKPROF kernels, but was passed (zeroed)
for many locks even in production kernels.
While here whack the tid argument from wlock hard and xlock hard.
There is no kbi change of any sort - "external" primitives still accept the
pair.
Mainly focus on files that use BSD 3-Clause license.
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.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
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.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
Initially, only tag files that use BSD 4-Clause "Original" license.
RelNotes: yes
Differential Revision: https://reviews.freebsd.org/D13133
Previously, symlinks in FreeBSD were artificially limited to PATH_MAX-2.
Add a short test case to verify the change.
Submitted by: Gaurav Gangalwar <ggangalwar AT isilon.com>
Reviewed by: kib
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12589
This shortens the lock hold time while not affecting corretness.
All the woken up threads end up competing can lose the race against
a completely unrelated thread getting the lock anyway.
clock_ts_to_ct has a KASSERT that the converted year fits into four
digits. By default (sysctl debug.allow_insane_settime is 0) the kernel
disallows a time too far in the future, using a value of 9999 366-day
years. However, clock_settime is epoch-relative and the assertion will
fail with a tv_sec corresponding to some 8030 years.
Avoid trying to be too clever, and just use a limit of 8000 365-day
years past the epoch.
Submitted by: Heqing Yan <scottieyan@gmail.com>
Reported by: Syzkaller (https://github.com/google/syzkaller)
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
kern.poweroff_on_panic which, when enabled, instructs a system to
power off on a panic instead of a reboot.
kern.powercyle_on_panic which, when enabled, instructs a system to
power cycle, if possible, on a panic instead of a reboot.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D13042
The PT_DETACH case above the sendsig: label already looped over all
threads clearing flags in td_dbgflags. Reuse this loop to clear
TDB_SUSPEND and move the logic out of the sendsig: block.
Most of the conditionals in the 'sendsig:' block are now only different
for PT_ATTACH vs other continue requests. Pull the PT_ATTACH-specific
logic up into the PT_ATTACH case and simplify the 'sendsig:' block. This
also permits moving the unlock of proctree_lock above the sendsig: label
since PT_KILL doesn't hold the lock and and the other cases all fall
through to the label.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D13073
This fixes a panic when attaching to an already-stopped process after
r325028. While here, clean up a few other things in the control flow
of the 'sendsig' section:
- Only check for P_STOPPED_TRACE rather than either of P_STOPPED_SIG
or P_STOPPED_TRACE for most ptrace requests. The signal handling
code in kern_sig.c never sets just P_STOPPED_SIG for a traced
process, so if P_STOPPED_SIG is stopped, P_STOPPED_TRACE should be
set anyway. Remove a related debug printf. Assuming P_STOPPED_TRACE
permits simplifications in the 'sendsig:' block.
- Move the block to clear the pending thread state up into a new
block conditional on P_STOPPED_TRACE and handle delivering pending
signals to the reporting thread and clearing the reporting thread's
state in this block.
- Consolidate case to send a signal to the process in a single case
for PT_ATTACH. The only case that could have been in the else before
was a PT_ATTACH where P_STOPPED_SIG was not set, so both instances
of kern_psignal() collapse down to just PT_ATTACH.
Reported by: pho, mmel
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D12837
This introduces a facility to EVENTHANDLER(9) for explicitly defining a
reference to an event handler list. This is useful since previously all
invokers of events had to do a locked traversal of the global list of
event handler lists in order to find the appropriate event handler list.
By keeping a pointer to the appropriate list an invoker can avoid this
traversal completely. The pointer is initialized with SYSINIT(9) during
the eventhandler stage. Users registering interest in events do not need
to know if the event is backed by such a list, since the list is added
to the global list of lists. As with lists that are not pre-defined it
is safe to register for the events before the list has been created.
This converts the process_* and thread_* events to using the new
facility, as these are events whose locked traversals end up showing up
significantly in ports build workflows (and presumably other workflows
with many short lived threads/procs). It may be advantageous to convert
other events to using the new facility.
The el_flags field is now unused, but leave it be so that this revision
can be MFC'd.
Reviewed by: bdrewery, markj, mjg
Approved by: rstone (mentor)
In collaboration with: ian
MFC after: 4 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12814
similar to the kernel memory allocator.
This simplifies NUMA allocation because the domain will be known at wait
time and races between failure and sleeping are eliminated. This also
reduces boilerplate code and simplifies callers.
A wait primitive is supplied for uma zones for similar reasons. This
eliminates some non-specific VM_WAIT calls in favor of more explicit
sleeps that may be satisfied without new pages.
Reviewed by: alc, kib, markj
Tested by: pho
Sponsored by: Netflix, Dell/EMC Isilon
Since the case of an empty chain was already covered, it si very likely
that the existing entry is matching. Skipping readlocking saves on lock
upgrade.
It is used on each new entry addition to decide whether to whack an existing
negative entry in order to prevent a blow out in size, but the parameter was
set years ago and never revisited.
Building with poudriere results in about 400 evictions per second which
unnecessarily grab entries from the hot list.
With the new parameter there are next to no evictions of the sort.
When multiple threads wish to report a tracing event to a debugger,
both threads call ptracestop() and one thread will win the race to be
the reporting thread (p->p_xthread). The debugger uses PT_LWPINFO
with the process ID to determine which thread / LWP is reporting an
event and the details of that event. This event is cleared as a side
effect of the subsequent ptrace event that resumed the process
(PT_CONTINUE, PT_STEP, etc.). However, ptrace() was clearing the
event identified by the LWP ID passed to the resume request even if
that wasn't the 'p_xthread'. This could result in clearing an event
that had not yet been observed by the debugger and leaving the
existing event for 'p_thread' pending so that it was reported a second
time.
Specifically, if the debugger stopped due to a software breakpoint in
one thread, but then switched to another thread that was used to
resume (e.g. if the user switched to a different thread and issued a
step), the resume request (PT_STEP) cleared a pending event (if any)
for the thread being stepped. However, the process immediately
stopped and the first thread reported it's breakpoint event a second
time. The debugger decremented the PC for "both" breakpoint events
which resulted in the PC now pointing into the middle of an
instruction (on x86) and a SIGILL fault when the process was resumed a
second time.
To fix, always clear the pending event for 'p_xthread' when resuming a
process. ptrace() still honors the requested LWP ID when enabling
single-stepping (PT_STEP) or setting a different PC (PT_CONTINUE).
Reported by: GDB testsuite (gdb.threads/continue-pending-status.exp)
Reviewed by: kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D12794
An off-by-one error has been present since the system call was first present
in 185878. It additionally became a memory corruption bug after change
324941. The failure is actually revealed by our existing AIO tests.
However, apparently nobody's been running those in 32-bit emulation mode.
Reported by: Coverity, cem
CID: 1382114
MFC after: 18 days
X-MFC-With: 324941
Sponsored by: Spectra Logic Corp
When using a kernel built with the GZIO config option, dumpon -z can be
used to configure gzip compression using the in-kernel copy of zlib.
This is useful on systems with large amounts of RAM, which require a
correspondingly large dump device. Recovery of compressed dumps is also
faster since fewer bytes need to be copied from the dump device.
Because we have no way of knowing the final size of a compressed dump
until it is written, the kernel will always attempt to dump when
compression is configured, regardless of the dump device size. If the
dump is aborted because we run out of space, an error is reported on
the console.
savecore(8) is modified to handle compressed dumps and save them to
vmcore.<index>.gz, as it does when given the -z option.
A new rc.conf variable, dumpon_flags, is added. Its value is added to
the boot-time dumpon(8) invocation that occurs when a dump device is
configured in rc.conf.
Reviewed by: cem (earlier version)
Discussed with: def, rgrimes
Relnotes: yes
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11723
In r322258 I made p1003_1b.aio_listio_max a tunable. However, further
investigation shows that there was never any good reason for that limit to
exist in the first place. It's used in two completely different ways:
* To size a UMA zone, which globally limits the number of concurrent
aio_suspend calls.
* To artifically limit the number of operations in a single lio_listio call.
There doesn't seem to be any memory allocation associated with this limit.
This change does two things:
* Properly names aio_suspend's UMA zone, and sizes it based on a new constant.
* Eliminates the artifical restriction on lio_listio. Instead, lio_listio
calls will now be limited by the more generous max_aio_queue_per_proc. The
old p1003_1b.aio_listio_max is now an alias for
vfs.aio.max_aio_queue_per_proc, so sysconf(3) will still work with
_SC_AIO_LISTIO_MAX.
Reported by: bde
Reviewed by: jhb
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D12120
While here cache-align chains.
This shortens longest found chain during poudriere -j 80 from 32 to 16.
Pushing this higher up will probably require allocation on boot.
VBAD type.
FFS ffs_write() VOP catches such vnodes and panics, other VOPs do not
check for the type and their behaviour is really undefined. The
comment claims that this support was done for 'badsect' to flag bad
sectors, we do not have such facility in kernel anyway.
Reported by: Dmitry Vyukov <dvyukov@google.com>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
- allocate value for new AT_HWCAP2 auxiliary vector on all platforms.
- expand 'struct sysentvec' by new 'u_long *sv_hwcap2', in exactly
same way as for AT_HWCAP.
MFC after: 1 month
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D12699
The end of the loop must re-lookup the next buf since the bufobj lock
is dropped in the loop body. If the lookup fails, the loop is restarted.
This mechanism non-obviously also terminates the loop when the end of
the buf list is reached. Split up the two loops termination cases to
make the code a bit less fragile. No functional change intended.
Reviewed by: kib
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12730
1) shorten the fast path by pushing the lockstat probe to the slow path
2) test for kernel panic only after it turns out we will have to spin,
in particular test only after we know we are not recursing
MFC after: 1 week
The previous limit of just one page is hit by ps.
The entire mechanism should be reworked, if not whacked. It seems the intent
is to reduce kernel dos-ability - some handlers wire the amount of memory
passed here. Handlers should probably stop wiring in the first place or in
the worst case indicate they are doing so so that the check is done only if
necessary. It should also probably be a counter, not a lock.
MFC after: 1 week
Not only this lock doesn't play any role here, dirtying it slows down
other things a little bit as giant-held checks (e.g. DROP_GIANT) are
spread all over the kernel.
MFC after: 1 week
All of the kernel dump implementations keep track of the current offset
("dumplo") within the dump device. However, except for textdumps, they
all write the dump sequentially, so we can reduce code duplication by
having the MI code keep track of the current offset. The new
dump_append() API can be used to write at the current offset.
This is needed to implement support for kernel dump compression in the
MI kernel dump code.
Also simplify dump_encrypted_write() somewhat: use dump_write() instead
of duplicating its bounds checks, and get rid of the redundant offset
tracking.
Reviewed by: cem
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11722
mbpool existed to support NICs with memory interfaces and all remaining
comsumers were removed earlier this year with NATM.
Reviewed by: jhb
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D10513
MNT_VNODE_FOREACH_ALL() is supposed to avoid returning doomed vnodes,
but the VI_DOOMED check it used was done without the vnode interlock
held, so it could race with a concurrent vgone().
Submitted by: Don Morris <don.morris@isilon.com>
Reviewed by: kib, mckusick
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12704
- Fix it by replacing m_cat() with m_prev->m_next = m_new
(m_cat() will try to append data - as a result, there will be no
fragmentation).
- Move some constants out of the loop.
Was previously tested with D4077.
Differential Revision: https://reviews.freebsd.org/D4090
The stop drops process lock, which allows the signal mask to be
changed and our selected signal might become blocked, i.e. should be
returned to the process queue instead of delivery.
Also, for the existing check of the process no longer having an
attached debugger, we should not loose the signal, but requeue it.
Reported and tested by: bdrewery
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Split two conditions into separate asserts. Print additional details,
like the signal number and action value.
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
In r324542 I neglected to reset the first and last fields of struct
unrhdr. This causes a tmpfs to fail the unr(9) consistency checks with
DIAGNOSTIC on. Fix this by resetting the fields by calling init_unrhdr.
While here, change a loop to use TAILQ_FOREACH_SAFE since it is more
readable and equally fast.
Reported by: David Wolfskill <david@catwhisker.org>
Approved by: rstone (mentor)
Sponsored by: Dell EMC Isilon
/compat/linux/path before /path. Stop following symbolic links when
looking up /compat/linux/path so dead symbolic links aren't ignored.
This allows syscalls like readlink(2) and lstat(2) to work on such links.
And open(2) will return an error now instead of trying /path.
"optimization". First, sendfile(..., SF_NOCACHE) frees pages without
checking whether those pages are mapped. This can leave the system
with mappings to free or repurposed pages. Second, a page can be
busied between the time of the current busy test and acquiring the
object lock. Essentially, the test performed before the object lock
is acquired can only be regarded as an optimization to short-circuit
further work on the page. It cannot, however, be relied upon to prove
that it is safe to free the page. Third, when sendfile(..., SF_NOCACHE)
was originally implemented, vm_page_deactivate_noreuse() did not yet
exist. Use vm_page_deactivate_noreuse() instead of vm_page_deactivate(),
because it comes closer to freeing the page.
In collaboration with: glebius
Discussed with: gallatin, kib, markj
X-MFC after: r324448
The manipulations done by mountcheckdirs() are not that useful during
the unmount, they can bring about unexpected security consequences.
Thic change effectively reverts the change in r73241.
The change also allows to simplify the handling of rootvnode global
variable.
Discussed with: mckusick, mjg, kib
Reviewed by: trasz
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D12366
posix_fallocate is logically equivalent to writing zero blocks to the
desired file size and there is no reason to prevent calling it in
capability mode. posix_fallocate already checked for the CAP_WRITE
right, so we merely need to list it in capabilities.conf.
Reviewed by: allanjude
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D12640
Previously before you could call unrhdr_delete you needed to
individually free every allocated unit. It is useful to be able to tear
down the unr without having to go through this process, as it is
significantly faster than freeing the individual units.
Reviewed by: cem, lidl
Approved by: rstone (mentor)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12591
all cache the last system time (uptime + boottime). Only the format
differs. Do not re-calculate the bintime and simply use the value
used to calculate the microtime and nanotime.
Group all the updates under the relevant comment. Remove obsoleted
XXX part.
Submitted by: Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after: 1 week
Sendfile() should match the error checking order of send() which
is currently:
SBS_CANTSENDMORE
so_error
SS_ISCONNECTED
Submitted by: Jason Eggleston <jason@eggnet.com>
Reviewed by: glebius
MFC after: 2 weeks
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12633
o Fall back to default m_ext free mech, using function pointer in
m_ext_free, and remove sf_ext_free() called directly from mbuf code.
Testing on modern CPUs showed no regression.
o Provide internally used flag EXT_FLAG_SYNC, to mark that I/O uses
SF_SYNC flag. Lack of the flag allows us not to dereference
ext_arg2, saving from a cache line miss.
o Create function sendfile_free_page() that later will be used, for
multi-page mbufs. For now compiler will inline it into
sendfile_free_mext().
In collaboration with: gallatin
Differential Revision: https://reviews.freebsd.org/D12615
in mb_free_ext() always use fields from the original refcount holding
mbuf (see. r296242) mbuf. Cuts another cache miss from mb_free_ext().
However, treat EXT_EXTREF mbufs differently, since they are different -
they don't have a refcount holding mbuf.
Provide longer comments in m_ext declaration to explain this change
and change from r296242.
In collaboration with: gallatin
Differential Revision: https://reviews.freebsd.org/D12615
All of these arguments are stored in m_ext, so there is no reason
to pass them in the argument list. Not all functions need the second
argument, some don't even need the first one. The second argument
lives in next cache line, so not dereferencing it is a performance
gain. This was discovered in sendfile(2), which will be covered by
next commits.
The second goal of this commit is to bring even more flexibility
to m_ext mbufs, allowing to create more fields in m_ext, opaque to
the generic mbuf code, and potentially set and dereferenced by
subsystems.
Reviewed by: gallatin, kbowling
Differential Revision: https://reviews.freebsd.org/D12615
properly dump all the sendqueues and not just the first one
History:
It appears that in the commit which introduced the code,
r165272, the array indexes of "sq_blocked[0]" and "td_name[i]"
were interchanged. In r180927 "td_name[i]" was corrected to
"td_name[0]", but "sq_blocked[0]" was left unchanged.
PR: 222624
Discussed with: kmacy @
MFC after: 1 week
Sponsored by: Mellanox Technologies
appearing only where the code explicitly set it, but since much of the
data was not initialized, '-1' appeared other places too, and led to
panics. Clear the allocated data before initializing nonzero values by
allocating with M_ZERO.
Submitted by: Doug Moore <dougm@rice.edu>
Reported by: Oleg V. Nauman <oleg@theweb.org.ua>, cy
Tested by: Oleg V. Nauman <oleg@theweb.org.ua>
MFC after: 1 week
X-MFC with: r324420
Differential Revision: https://reviews.freebsd.org/D12627
nodes to allocate for the blist, and to initialize them. The computation
can be done much more quickly by identifying the terminating node, if any,
at every level of the tree and then summing the number of nodes at each
level that precedes the topmost terminator. The initialization can also be
done quickly, since settings at the root mark the tree as all-allocated, and
only a few terminator nodes need to be marked in the rest of the tree.
Eliminate blst_radix_init, and perform its two functions more simply in
blist_create.
The allocation of the blist takes places in two pieces, but there's no good
reason to do so, when a single allocation is sufficient, and simpler.
Allocate the blist struct, and the array of nodes associated with it, with a
single allocation.
Submitted by: Doug Moore <dougm@rice.edu>
Reviewed by: markj (an earlier version)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11968
The detach case is slightly complicated by the fact that some in-kernel
consumers may want to know before a device detaches (so they can release
related resources, stop using the device, etc), but the detach can fail. So
there are pre- and post-detach notifications for those consumers who need to
handle all cases.
A couple salient comments from the review, they amount to some helpful
documentation about these events, but there's currently no good place for
such documentation...
Note that in the current newbus locking model, DETACH_BEGIN and
DETACH_COMPLETE/FAILED sequence of event handler invocation might interweave
with other attach/detach events arbitrarily. The handlers should be prepared
for such situations.
Also should note that detach may be called after the parent bus knows the
hardware has left the building. In-kernel consumers have to be prepared to
cope with this race.
Differential Revision: https://reviews.freebsd.org/D12557
When the EVENTHANDLER(9) subsystem was created, it was a documented feature
that an eventhandler callback function could safely deregister itself. In
r200652 that feature was inadvertantly broken by adding drain-wait logic to
eventhandler_deregister(), so that it would be safe to unload a module upon
return from deregistering its event handlers.
There are now 145 callers of EVENTHANDLER_DEREGISTER(), and it's likely many
of them are depending on the drain-wait logic that has been in place for 8
years. So instead of creating a separate eventhandler_drain() and adding it
to some or all of those 145 call sites, this creates a separate
eventhandler_drain_nowait() function for the specific purpose of
deregistering a callback from within the running callback.
Differential Revision: https://reviews.freebsd.org/D12561
connection was reset by the remote end, sendfile() would just report
ENOTCONN instead of ECONNRESET.
Submitted by: Jason Eggleston <jason@eggnet.com>
Reviewed by: glebius
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12575
Lookups of the sort are rare compared to regular ones and succesfull ones
result in removing entries from the cache.
In the current code buckets are rlocked and a trylock dance is performed,
which can fail and cause a restart. Fixing it will require a little bit
of surgery and in order to keep the code maintaineable the 2 cases have
to split.
MFC after: 1 week
When using the default address list nam is still valid, the code in
r324054 assumed that is was NULL.
Reported by: Guy Yur <guyyur@gmail.com>
Tested by: Guy Yur <guyyur@gmail.com>
Previous code would always spin once before checking the lock. But a lock
with e.g. 6 readers is not going to become free in the duration of once spin
even if they start draining immediately.
Conservatively perform one for each reader.
Note that the total number of allowed spins is still extremely small and is
subject to change later.
MFC after: 1 week
Improved logging added in r323879 exposed an error during
attach. We need the irq, not the rid to work correctly. em uses
shared irqs, so it will use the same irq for TX as RX. bnxt does
not use shared irqs, or TX irqs at all, so there's no need to set
the TX irq affinity.
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12496
spin first instant of instantly re-readoing and don't re-read after
spinning is finished - the state is already known.
Note the code is subject to significant changes later.
MFC after: 1 week
A sysctl can have a custom handler that may access data that is initialized
via SYSINIT(9) or via a module event handler (also invoked via SYSINIT).
Thus, it is not safe to allow access to the module's sysctl-s until
the initialization is performed. Likewise, we should not allow access
to teh sysctl-s after the module is uninitialized.
The latter is easy to achieve by properly ordering linker_file_unregister_sysctls
and linker_file_sysuninit.
The former is not as easy for two reasons:
- the initialization may depend on tunables which get set when sysctl-s are
registered, so we need to set the tunables before running sysinit-s
- the initialization may try to dynamically add more sysctl-s under statically
defined sysctl nodes
So, this change splits the sysctl setup into two phases. In the first phase
the sysctl-s are registered as before but they are disabled and hidden from
consumers. In the second phase, done after sysinit-s, normal access to the
sysctl-s is enabled.
The change should affect only dynamic module loading and unloading after
the system boot-up. Nothing changes for sysctl-s compiled into the kernel
and sysctl-s in preloaded modules.
Discussed with: hselasky, ian, jhb
Reviewed by: julian, kib
MFC after: 2 weeks
Sponsored by: Panzura
Differential Revision: https://reviews.freebsd.org/D12545
Violators may define _WANT_SOCKET and _WANT_UNPCB respectively and
are not guaranteed for stability of the structures. The violators
list is the the usual one: libprocstat(3) and netstat(1) internally
and lsof in ports.
In struct xunpcb remove the inclusion of kernel structure and add
a bunch of spare fields. The xsocket already has socket not included,
but add there spares as well. Embed xsockbuf into xsocket.
Sort declarations in sys/socketvar.h to separate kernel only from
userland available ones.
PR: 221820 (exp-run)
Previously, uiomove_object_page() would maintain LRU by requeuing the
accessed page. This involves acquiring one of the heavily contended page
queue locks. Moreover, it is unnecessarily expensive for pages in the
active queue.
As of r254304 the page daemon continually performs a slow scan of the
active queue, with the effect that unreferenced pages are gradually
moved to the inactive queue, from which they can be reclaimed. Prior to
that revision, the active queue was scanned only during shortages of
free and inactive pages, meaning that unreferenced pages could get
"stuck" in the queue. Thus, tmpfs was required to use the inactive queue
and requeue pages in order to maintain LRU. Now that this is no longer
the case, tmpfs I/O operations can use the active queue and avoid the
page queue locks in most cases, instead setting PGA_REFERENCED on
referenced pages to provide pseudo-LRU.
Reviewed by: alc (previous version)
MFC after: 2 weeks
some still useful bits of the reverted revision.
The problem with the committed fix is that there are still issues with
returning from NMI, when NMI interrupted kernel in a moment where the
kernel segments selectors were still not loaded into registers. If
this happens, the NMI return would loose the userspace selectors
because r323722 does not reload segment registers on return to kernel
mode.
Fixing the problem is complicated. Since an alternative approach to
handle the original bug exists, it makes sence to stop adding more
complexity.
Discussed with: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
This fixes kernel crashes due to misaligned accesses to the 64-bit
time_t embedded in struct namecache_ts in MIPS n32 kernels.
MFC after: 1 week
Sponsored by: DARPA / AFRL
If the filesystem is not exported directly return NULL.
If no address is given and filesystem is exported using some default
one return it directly, if it doesn't have a default one directly
return NULL.
Reviewed by: kib, bapt
MFC after: 1 week
Sponsored by: Gandi.net
Differential Revision: https://reviews.freebsd.org/D12505
Said checks were inherently racy anyway as jokers could unmap target areas
before the handler got around to accessing them.
This saves time by avoiding locking the address space.
MFC after: 1 week
tid must be equal to curthread and the target routine was already reading
it anyway, which is not a problem. Not passing it as a parameter allows for
a little bit shorter code in callers.
MFC after: 1 week
Add a DDB command that mirrors sysctl debug.witness.badstacks.
Reapply r323935 after fixing trivial deficiency. I forgot to compile with
WITNESS enabled. Thanks emaste@ for fixing the build while I was asleep.
Reported by: rstone
Reviewed by: rstone (previous version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12468
Previously, it was just a pointer which was copied, but
some callers pass in a stack variable which will go out of scope.
Add GROUPTASK_NAMELEN macro (32) and snprintf() the name into it,
using "grouptask" if name is NULL. We can now safely include
gtask->gt_name in console messages.
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12449
check hash to cylinder groups. If a check hash fails when a cylinder
group is read, no further allocations are attempted in that cylinder
group until it has been fixed by fsck. This avoids a class of
filesystem panics related to corrupted cylinder group maps. The
hash is done using crc32c.
Check hases are added only to UFS2 and not to UFS1 as UFS1 is primarily
used in embedded systems with small memories and low-powered processors
which need as light-weight a filesystem as possible.
Specifics of the changes:
sys/sys/buf.h:
Add BX_FSPRIV to reserve a set of eight b_xflags that may be used
by individual filesystems for their own purpose. Their specific
definitions are found in the header files for each filesystem
that uses them. Also add fields to struct buf as noted below.
sys/kern/vfs_bio.c:
It is only necessary to compute a check hash for a cylinder
group when it is actually read from disk. When calling bread,
you do not know whether the buffer was found in the cache or
read. So a new flag (GB_CKHASH) and a pointer to a function to
perform the hash has been added to breadn_flags to say that the
function should be called to calculate a hash if the data has
been read. The check hash is placed in b_ckhash and the B_CKHASH
flag is set to indicate that a read was done and a check hash
calculated. Though a rather elaborate mechanism, it should
also work for check hashing other metadata in the future. A
kernel internal API change was to change breada into a static
fucntion and add flags and a function pointer to a check-hash
function.
sys/ufs/ffs/fs.h:
Add flags for types of check hashes; stored in a new word in the
superblock. Define corresponding BX_ flags for the different types
of check hashes. Add a check hash word in the cylinder group.
sys/ufs/ffs/ffs_alloc.c:
In ffs_getcg do the dance with breadn_flags to get a check hash and
if one is provided, check it.
sys/ufs/ffs/ffs_vfsops.c:
Copy across the BX_FFSTYPES flags in background writes.
Update the check hash when writing out buffers that need them.
sys/ufs/ffs/ffs_snapshot.c:
Recompute check hash when updating snapshot cylinder groups.
sys/libkern/crc32.c:
lib/libufs/Makefile:
lib/libufs/libufs.h:
lib/libufs/cgroup.c:
Include libkern/crc32.c in libufs and use it to compute check
hashes when updating cylinder groups.
Four utilities are affected:
sbin/newfs/mkfs.c:
Add the check hashes when building the cylinder groups.
sbin/fsck_ffs/fsck.h:
sbin/fsck_ffs/fsutil.c:
Verify and update check hashes when checking and writing cylinder groups.
sbin/fsck_ffs/pass5.c:
Offer to add check hashes to existing filesystems.
Precompute check hashes when rebuilding cylinder group
(although this will be done when it is written in fsutil.c
it is necessary to do it early before comparing with the old
cylinder group)
sbin/dumpfs/dumpfs.c
Print out the new check hash flag(s)
sbin/fsdb/Makefile:
Needs to add libufs now used by pass5.c imported from fsck_ffs.
Reviewed by: kib
Tested by: Peter Holm (pho)
It doesn't appear to be safe to use gtask->gt_name.
Reported by: Mark Johnston, Jenkins
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12448
Move handling of these three pathconf() variables out of vop_stdpathconf()
and into devfs_pathconf() as TTY devices can only be devfs files. In
addition, only return settings for these three variables for devfs devices
whose device switch has the D_TTY flag set.
Discussed with: bde, kib
Sponsored by: Chelsio Communications
Check the return code of intr_setaffinity() and log any errors
it returns. When a qid is not located, log an error before returning
failure. Also, use __func__ rather than hardcoding the function name
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12436
Previously had the same short and long description as taskqueues.
This could cause problems with memguard(9) and vmstat -m which use
the short description as a unique identifier.
Reviewed by: sbruno
Approved by: sbruno (mentor)
MFC after: 3 days
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12438
If vrele() changes the hold count to zero, it needs to acquire the
vnode lock.
Sponsored by: The FreeBSD Foundation
Discussed with: avg
X-MFC with: r323578
One consequence of the patch is that msyncing unlinked file mappings
no longer reduces the amount of the dirty memory in the system, but I
do not think that there are users of msync(2) that utilize it for such
side-effect.
Reported and tested by: tjil
PR: 222356
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D12411
Suppose that userspace is executing with the non-standard segment
descriptors. Then, until exception or interrupt handler executed
SET_KERNEL_SEGS, kernel is still executing with user %ds, %es and %fs.
If an interrupt occurs in this window, the interrupt handler is
executed unsafely, relying on usability of the usermode registers. If
the interrupt results in the context switch on return, the
contamination of the kernel state spreads to the thread we switched
to. As result, kernel data accesses might fault or, if only the base
is changed, completely messed up.
More, if the user segment was allocated in LDT, another thread might
mark the descriptor as invalid before doreti code tried to reload
them. In this case kernel panics.
The issue exists for all exception entry points which use trap gate,
and thus do not automatically disable interrupts on entry, and for
lcall_handler.
Fix is two-fold: first, we need to disable interrupts for all kernel
entries, changing the IDT descriptor types from trap gate to interrupt
gate. Interrupts are re-enabled not earlier than the kernel segments
are loaded into the segment registers. Second, we only load the
segment registers from the trap frame when returning to usermode. For
the later, all interrupt return paths must happen through the doreti
common code.
There is no way to disable interrupts on call gate, which is the
supposed mode of servicing for lcall $7,$0 syscalls. Change the LDT
descriptor 0 into a code segment type and point it to the userspace
trampoline which redirects the syscall to int $0x80.
All the measures make the segment register handling similar to that of
amd64. We do not apply amd64 optimizations of not reloading segment
registers on return from the syscall.
Reported by: Maxime Villard <max@m00nbsd.net>
Tested by: pho (the non-lcall part)
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D12402
Modify blst_leaf_alloc to find allocations that cross the boundary between
one leaf node and the next when those two leaves descend from the same
meta node.
Update the hint field for leaves so that it represents a bound on how
large an allocation can begin in that leaf, where it currently represents
a bound on how large an allocation can be found within the boundaries of
the leaf.
The first phase of blst_leaf_alloc currently shrinks sequences of
consecutive 1-bits in mask until each has been shrunken by count-1 bits,
so that any bits remaining show where an allocation can begin, or until
all the bits have disappeared, in which case the allocation fails. This
change amends that so that the high-order bit is copied, as if, when the
last block was free, it was followed by an endless stream of free
blocks. It also amends the early stopping condition, so that the shrinking
of 1-sequences stops early when there are none, or there is only one
unbounded one remaining.
The search for the first set bit is unchanged, and the code path
thereafter is mostly unchanged unless the first set bit is in a position
that makes some of those copied sign bits matter. In that case, we look
for a next leaf, and at what blocks it can provide, to see if a
cross-boundary allocation is possible.
The hint is updated on a successful allocation that clears the last bit,
but it not updated on a failed allocation that leaves the last bit
set. So, as long as the last block is free, the hint value for the leaf is
large. As long as the last block is free, and there's a next leaf, a large
allocation can begin here, perhaps. A stricter rule than this would mean
that allocations and frees in one leaf could require hint updates to the
preceding leaf, and this change seeks to leave the freeing code
unmodified.
Define BLIST_BMAP_MASK, and use it for bit masking in blst_leaf_free and
blist_leaf_fill, as well as in blst_leaf_alloc.
Correct a panic message in blst_leaf_free.
Submitted by: Doug Moore <dougm@rice.edu>
Reviewed by: markj (an earlier version)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11819
This was really too big of a commit even if everything worked, but there
are multiple new issues introduced in the one huge commit, so it's not
worth keeping this until it's fixed.
I'll work on splitting this up into logical chunks and introduce them one
at a time over the next week or two.
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
When a newborn socket moves from incomplete queue to complete
one, we need to obtain the listening socket lock after the child,
which is a wrong order. The old code did that in potentially
endless loop of mtx_trylock(). The new one does only one attempt
of mtx_trylock(), and in case of failure references listening
socket, unlocks child and locks everything in right order. In
case if listening socket shuts down during that, just bail out.
Reported & tested by: Jason Eggleston <jeggleston llnw.com>
Reported & tested by: Jason Wolfe <jason llnw.com>
A new 'u_long *sv_hwcap' field is added to 'struct sysentvec'. A
process ABI can set this field to point to a value holding a mask of
architecture-specific CPU feature flags. If an ABI does not wish to
supply AT_HWCAP to processes the field can be left as NULL.
The support code for AT_EHDRFLAGS was already present on all systems,
just the #define was not present. This is a step towards unifying the
AT_* constants across platforms.
Reviewed by: kib
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D12290
As long as mnt_ref is not zero there can be a consumer that might try
to access mnt_vnodecovered. For this reason the covered vnode must not
be freed until mnt_ref goes to zero.
So, move the release of the covered vnode to vfs_mount_destroy.
Reviewed by: kib
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D12329
The problem is that fdrop() requires syscall context, as it may
enter sleep in some cases. The reason to use it in the original
non-blocking sendfile implementation, was to avoid use of global
ACCEPT_LOCK() on every I/O completion. Now in head sorele() no
longer requires this lock.
in UNIX sockets.
o Check that socket is still connected in uipc_ready(). If not
we are responsible to free mbufs.
o In uipc_send() if socket appears to be disconnected, but we
are sending data with pending I/Os, don't free mbufs.
Reported by: Kevin Bowling <kbowling llnw.com>
Tested by: Kevin Bowling <kbowling llnw.com>
PR: 222259
Reported by: Mark Martinec <Mark.Martinec ijs.si>
MFC after: 3 days
by Matt Macy as well as other changes which he has accepted via pull
request to his github repo at https://github.com/mattmacy/networking/
This should bring -CURRENT and the github repo into close enough sync to
allow small feature branches rather than a large chain of interdependant
patches being developed out of tree. The reset of the synchronization
should be able to be completed on github by splitting the remaining
changes that are not yet ready into short feature branches for later
review as smaller commits.
Here is a summary of changes included in this patch:
1) More checks when INVARIANTS are enabled for eariler problem
detection
2) Group Task Queue cleanups
- Fix use of duplicate shortdesc for gtaskqueue malloc type.
Some interfaces such as memguard(9) use the short description to
identify malloc types, so duplicates should be avoided.
3) Allow gtaskqueues to use ithreads in addition to taskqueues
- In some cases, this can improve performance
4) Better logging when taskqgroup_attach*() fails to set interrupt
affinity.
5) Do not start gtaskqueues until they're needed
6) Have mp_ring enqueue function enter the ABDICATED rather than BUSY
state. This moves the TX to the gtaskq and allows processing to
continue faster as well as make TX batching more likely.
7) Add an ift_txd_errata function to struct if_txrx. This allows
drivers to inspect/modify mbufs before transmission.
8) Add a new IFLIB_NEED_ZERO_CSUM for drivers to indicate they need
checksums zeroed for checksum offload to work. This avoids modifying
packet data in the TX path when possible.
9) Use ithreads for iflib I/O instead of taskqueues
10) Clean up ioctl and support async ioctl functions
11) Prefetch two cachlines from each mbuf instead of one up to 128B. We
often need to parse packet header info beyond 64B.
12) Fix potential memory corruption due to fence post error in
bit_nclear() usage.
13) Improved hang detection and handling
14) If the packet is smaller than MTU, disable the TSO flags.
This avoids extra packet parsing when not needed.
15) Move TCP header parsing inside the IS_TSO?() test.
This avoids extra packet parsing when not needed.
16) Pass chains of mbufs that are not consumed by lro to if_input()
rather call if_input() for each mbuf.
17) Re-arrange packet header loads to get as much work as possible done
before a cache stall.
18) Lock the context when calling IFDI_ATTACH_PRE()/IFDI_ATTACH_POST()/
IFDI_DETACH();
19) Attempt to distribute RX/TX tasks across cores more sensibly,
especially when RX and TX share an interrupt. RX will attempt to
take the first threads on a core, and TX will attempt to take
successive threads.
20) Allow iflib_softirq_alloc_generic() to request affinity to the same
cpus an interrupt has affinity with. This allows TX queues to
ensure they are serviced by the socket the device is on.
21) Add new iflib sysctls to net.iflib:
- timer_int - interval at which to run per-queue timers in ticks
- force_busdma
22) Add new per-device iflib sysctls to dev.X.Y.iflib
- rx_budget allows tuning the batch size on the RX path
- watchdog_events Count of watchdog events seen since load
23) Fix error where netmap_rxq_init() could get called before
IFDI_INIT()
24) e1000: Fixed version of r323008: post-cold sleep instead of DELAY
when waiting for firmware
- After interrupts are enabled, convert all waits to sleeps
- Eliminates e1000 software/firmware synchronization busy waits after
startup
25) e1000: Remove special case for budget=1 in em_txrx.c
- Premature optimization which may actually be incorrect with
multi-segment packets
26) e1000: Split out TX interrupt rather than share an interrupt for
RX and TX.
- Allows better performance by keeping RX and TX paths separate
27) e1000: Separate igb from em code where suitable
Much easier to understand separate functions and "if (is_igb)" than
previous tests like "if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC))"
#blamebruno
Reviewed by: sbruno
Approved by: sbruno (mentor)
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D12235
for analyzing the radix tree structures and reporting on the number, and
sizes, of maximal intervals of free blocks. The report includes the number
of maximal intervals, and also the number of them in each of several size
ranges, from small (size 1, or 3 to 4) to large (28657 to 46367) with size
boundaries defined by Fibonacci numbers. The report is written in the test
tool with the 's' command, or in a running kernel by sysctl.
The analysis of the radix tree frequently computes the position of the lone
bit set in a u_daddr_t, a computation that also appears in leaf allocation.
That computation has been moved into a function of its own, and optimized
for cases where an inlined machine instruction can replace the usual binary
search.
Submitted by: Doug Moore <dougm@rice.edu>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11906
it to a random value between 100 and 1123, rather than 0 as before.
Submitted by: Marie Helene Kvello-Aune <marieheleneka@gmail.com>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D5336
namecache_ts differs from mere namecache by few fields placed mid struct.
The access to the last element (the name) is thus special-cased.
The standard solution is to put new fields at the very beginning anad
embedd the original struct. The pointer shuffled around points to the
embedded part. If needed, access to new fields can be gained through
__containerof.
MFC after: 1 week
While these locks are guarnteed to not share their respective cache lines,
their current placement leaves unnecessary holes in lines which preceeded them.
For instance the annotation of vm_page_queue_free_mtx allows 2 neighbour
cachelines (previously separate by the lock) to be collapsed into 1.
The annotation is only effective on architectures which have it implemented in
their linker script (currently only amd64). Thus locks are not converted to
their not-padaligned variants as to not affect the rest.
MFC after: 1 week
It would be better to fix API consumers to not pass NULL there - most of them,
such as gmirror, already contain the neccessary checks - but this is easier
and much less error-prone.
One known user-visible result is that it fixes panic on a failed "graid label".
PR: 221846
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
This adds support in pass(4) for data to be described with a
scatter-gather list (sglist) to augment the existing (single) virtual
address.
Differential Revision: https://reviews.freebsd.org/D11361
Submitted by: Chuck Tuffli
Reviewed by: imp@, scottl@, kenm@
The old code allowed calling vdrop() before insmntque() to place the vnode back
onto the freelist for later recycling. Some downstream consumers may rely on
this support. Normally insmntque() failing is fine since is uses vgone() and
immediately frees the vnode rather than attempting to add it to the freelist if
vdrop() were used instead.
Also assert that vhold() cannot be used on such a vnode.
Reviewed by: kib, cem, markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12126
Print the full conflicting oid path, and include the function name in the
warning so it is clear that the warnings are sysctl-related.
PR: 221853
Submitted by: Fabian Keil <fk AT fabiankeil.de> (earlier version)
Sponsored by: Dell EMC Isilon
Improve scheduler performance by flattening nonsensical topology layers
(layers with only one child don't serve any purpose).
This is especially relevant on non-AMD Zen systems after r322776. On my
dual core Intel laptop, this brings the kern.sched.topology_spec table down
from three levels to two.
Submitted by: jeff
Reviewed by: attilio
Sponsored by: Dell EMC Isilon
The AIO job holds a reference on the associated file descriptor, so the
socket's count should already be > 0. This fixes a LOR with the socket
buffer lock after recent socket locking changes in HEAD.
Sponsored by: Chelsio Communications
removal of the "blk" parameter from blst_meta_alloc() had the unintended
effect of generating an out-of-range allocation when the cursor reaches
the end of the tree if the number of managed blocks in the tree equals
the so-called "radix" (which in the blist code is not the standard notion
of what a radix is but rather the maximum number of leaves in a tree of
the current height.) In other words, only certain swap configurations
were affected, which is why earlier testing did not reveal the problem.
Submitted by: Doug Moore <dougm@rice.edu>
Reported by: pho, kib
Tested by: pho
X-MFC with: r322459
Differential Revision: https://reviews.freebsd.org/D12106
via soisdisconnected(), and in the earlier unlock earlier to avoid lock
recursion.
This fixes a situation when a socket on accept queue is reset before being
accepted.
Reported by: Jason Eggleston <jeggleston llnw.com>
A follow-up to r322836.
Warnings for the unused declaration were breaking some second tier
architectures, but did not show up in Clang on x86.
Reported by: markj (ddb.4), emaste (declaration)
Sponsored by: Dell EMC Isilon
When debugging a deadlock, it is useful to follow the full chain of locks as
far as possible.
Reviewed by: jhb
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12115
Rather than repeatedly nesting loops, separate concerns with a single loop
per call stack level. Use a table to drive the recursive routine. Handle
missing topology layers more gracefully (infer a single unit).
Analyze some additional optional layers which may be present on e.g. AMD Zen
systems (groups, aka dies, per package; and cachegroups, aka CCXes, per
group).
Display that additional information in the boot-time topology information,
when it is relevent (non-one).
Reviewed by: markj@, mjoras@ (earlier version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12019
This mode allows other clean buffers to arrive while we flush the buf
lists for the vnode, which is fine for the targeted use. We only need
that all buffers existed at the time of the function start were
flushed. In fact, only one assert has to be relaxed.
In collaboration with: pho
Reviewed by: rmacklem
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
X-Differential revision: https://reviews.freebsd.org/D12083
Right now we only need to pad when writing kernel dump headers, so
flatten three related subroutines into one. The encrypted kernel dump
code already writes out its key in a dumper.blocksize-sized block.
No functional change intended.
Reviewed by: cem, def
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11647
This helps simplify the code in kern_shutdown.c and reduces the number
of globally visible functions.
No functional change intended.
Reviewed by: cem, def
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11603
dump_start() and dump_finish() are responsible for writing kernel dump
headers, optionally writing the key when encryption is enabled, and
initializing the initial offset into the dump device.
Also remove the unused dump_pad(), and make some functions static now that
they're only called from kern_shutdown.c.
No functional change intended.
Reviewed by: cem, def
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D11584
sbuf is filled to capacity by vsnprintf(), the loop exits without error, and
the sbuf is not marked as auto-extendable.
SBUF_HASROOM() evaluates true if there is room for one or more non-NULL
characters, but in the case that the sbuf was filled exactly to capacity,
SBUF_HASROOM() evaluates false. Consequently, sbuf_vprintf() incorrectly
assigns an ENOMEM error to the sbuf when in fact everything is fine, in turn
poisoning the buffer for all subsequent operations.
Correct by moving the ENOMEM assignment into the loop where it can be made
unambiguously.
As a related safety net change, explicitly check for the zero bytes drained
case in sbuf_drain() and set EDEADLK as the error. This avoids an infinite loop
in sbuf_vprintf() if a drain function were to inadvertently return a value of
zero to sbuf_drain().
Reviewed by: cem, jtl, gallatin
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D8535
during drain operations. When an sbuf is configured to use this feature by way
of the SBUF_DRAINTOEOR sbuf_new() flag, top-level sections started with
sbuf_start_section() create a record boundary marker that is used to avoid
flushing partial records.
Reviewed by: cem,imp,wblock
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D8536
it automatically after it runs.
The config_intrhook mechanism allows a driver to stall the boot process
until device(s) required for booting are available, by not allowing system
inits to proceed until all intrhook functions have been unregistered.
Virtually all existing code simply unregisters from within the hook function
when it gets called.
This new function makes that common usage more convenient. Instead of
allocating and filling in a struct, passing it to a function that might (in
theory) fail, and checking the return code, now a driver can simply call
this cannot-fail routine, passing just the intrhook function and its arg.
Differential Revision: https://reviews.freebsd.org/D11963
