syscons spinlock for the output routine alone. It is better to extend
the coverage of the first syscons spinlock added in r162285. 2 locks
might work with complicated juggling, but no juggling was done. What
the 2 locks actually did was to cover some of the missing locking in
each other and deadlock less often against each other than a single
lock with larger coverage would against itself. Races are preferable
to deadlocks here, but 2 locks are still worse since they are harder
to understand and fix.
Prefer deadlocks to races and merge the second lock into the first one.
Extend the scope of the spinlocking to all of sc_cnputc() instead of
just the sc_puts() part. This further prefers deadlocks to races.
Extend the kdb_active hack from sc_puts() internals for the second lock
to all spinlocking. This reduces deadlocks much more than the other
changes increases them. The s/p,10* test in ddb gets much further now.
Hide this detail in the SC_VIDEO_LOCK() macro. Add namespace pollution
in 1 nested #include and reduce namespace pollution in other nested
#includes to pay for this.
Move the first lock higher in the witness order. The second lock was
unnaturally low and the first lock was unnaturally high. The second
lock had to be above "sleepq chain" and/or "callout" to avoid spurious
LORs for visual bells in sc_puts(). Other console driver locks are
already even higher (but not adjacent like they should be) except when
they are missing from the table. Audio bells also benefit from the
syscons lock being high so that audio mutexes have chance of being
lower. Otherwise, console drviver locks should be as low as possible.
Non-spurious LORs now occur if the bell code calls printf() or is
interrupted (perhaps by an NMI) and the interrupt handler calls
printf(). Previous commits turned off many bells in console i/o but
missed ones done by the teken layer.
(NB: This was likely a mismerge from XNU in audit support, where the
text argument to setlogin(2) is captured -- but as a text token,
whereas this change uses the dedicated login-name field in struct
audit_record.)
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
ftruncate(2) system call. This was not required by the Common
Criteria, which needed only open-time audit.
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Such processes are stopped synchronously by a direct call to
ptracestop(SIGTRAP) upon exec. P2_PTRACE_FSTP causes the exec()ing thread
to suspend itself while waiting for a SIGSTOP that never arrives.
Reviewed by: kib
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D7576
- Read interrupt properties at bus enumeration time and store
it into global mapping table.
- At bus_activate_resource() time, given mapping entry is resolved and
connected to real interrupt source. A copy of mapping entry is attached
to given resource.
- At bus_setup_intr() time, mapping entry stored in resource is used
for delivery of requested interrupt configuration.
- For MSI/MSIX interrupts, mapping entry is created within
pci_alloc_msi()/pci_alloc_msix() call.
- For legacy PCI interrupts, mapping entry must be created within
pcib_route_interrupt() by pcib driver itself.
Reviewed by: nwhitehorn, andrew
Differential Revision: https://reviews.freebsd.org/D7493
aio_aqueue() calls aio_init_aioinfo() as the first action. There is no
need to duplicate the code in kern_aio_fsync().
Also fix indent for aio_aqueue() definition.
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D7523
Right now, userspace (fast) gettimeofday(2) on x86 only works for
RDTSC. For older machines, like Core2, where RDTSC is not C2/C3
invariant, and which fall to HPET hardware, this means that the call
has both the penalty of the syscall and of the uncached hw behind the
QPI or PCIe connection to the sought bridge. Nothing can me done
against the access latency, but the syscall overhead can be removed.
System already provides mappable /dev/hpetX devices, which gives
straight access to the HPET registers page.
Add yet another algorithm to the x86 'vdso' timehands. Libc is updated
to handle both RDTSC and HPET. For HPET, the index of the hpet device
to mmap is passed from kernel to userspace, index might be changed and
libc invalidates its mapping as needed.
Remove cpu_fill_vdso_timehands() KPI, instead require that
timecounters which can be used from userspace, to provide
tc_fill_vdso_timehands{,32}() methods. Merge i386 and amd64
libc/<arch>/sys/__vdso_gettc.c into one source file in the new
libc/x86/sys location. __vdso_gettc() internal interface is changed
to move timecounter algorithm detection into the MD code.
Measurements show that RDTSC even with the syscall overhead is faster
than userspace HPET access. But still, userspace HPET is three-four
times faster than syscall HPET on several Core2 and SandyBridge
machines.
Tested by: Howard Su <howard0su@gmail.com>
Sponsored by: The FreeBSD Foundation
MFC after: 1 month
Differential revision: https://reviews.freebsd.org/D7473
it (either async or sync drain).
At this moment the only user of drain is TCP, but TCP wouldn't reschedule a
callout after it has drained it, since it drains only when a tcpcb is closed.
This for now the problem isn't observed.
Submitted by: rrs
Make the kern_fsync() function public, so that it can be used by other
parts of the kernel. Fix up existing consumers to make use of it.
Requested by: kib
If the caller of sem_post() wakes up a thread sleeping via sem_wait()
before it clears the has_waiters flag, the caller of sem_wait() has no way of
knowing when it is safe to destroy the semaphore and reuse the memory. This is
because the caller of sem_post() may be interrupted between the wake step and
the clearing of has_waiters. It will then write into the has_waiters flag in
userspace after being preempted for some unknown amount of time.
Reviewed by: jhb, kib, vangyzen
Approved by: kib (mentor), vangyzen (mentor)
MFC after: 2 weeks
Sponsored by: Dell Inc.
Differential Revision: https://reviews.freebsd.org/D7505
Standard VOP_FSYNC() implementation just syncs data buffers, and due
to this, is the correct and efficient implementation for msdosfs or
any other filesystem which uses bufer cache trivially. Provide
globally visible wrapper vop_stdfdatasync_buf() for future consumption
by other filesystems.
Reviewed by: mckusick
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D7471
The syscall is a trivial wrapper around new VOP_FDATASYNC(), sharing
code with fsync(2). For all filesystems, this commit provides the
implementation which delegates the work of VOP_FDATASYNC() to
VOP_FSYNC(). This is functionally correct but not efficient.
This is not yet POSIX-compliant implementation, because it does not
ensure that queued AIO requests are completed before returning.
Reviewed by: mckusick
Discussed with: avg (ZFS), jhb (AIO part)
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D7471
It was remarkably hard to trace all current threads. "show pcpu" only
showed the pid, and there was nothing (?) better than searching ps output
to find the tids on CPUs. This change simplifies the search, but you
still have to trace the tid for each CPU manually.
incorrect from the error cases in exec_map_first_page(). They are
unnecessary because we automatically unbusy the page in vm_page_free()
when we remove it from the object. The calls are incorrect because they
happen after the page is freed, so we might actually unbusy the page
after it has been reallocated to a different object. (This error was
introduced in r292373.)
Reviewed by: kib
MFC after: 1 week
- Move group task queue into kern/subr_gtaskqueue.c
- Change intr_enable to return an int so it can be detected if it's not
implemented
- Allow different TX/RX queues per set to be different sizes
- Don't split up TX mbufs before transmit
- Allow a completion queue for TX as well as RX
- Pass the RX budget to isc_rxd_available() to allow an earlier return
and avoid multiple calls
Submitted by: shurd
Reviewed by: gallatin
Approved by: scottl
Differential Revision: https://reviews.freebsd.org/D7393
It was added in r153192 for XFS and doesn't appear to have been used for
anything else. XFS was disconnected in r241607 and removed entirely in
r247631.
Reported by: mlaier
Reviewed by: imp, kib
Differential Revision: https://reviews.freebsd.org/D7468
processes which combine kernel and non-kernel threads, e.g. nfsd. For
such processes, termination of a kthread must recheck signal delivery
among other threads according to masks.
Reported and tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Several files use the internal name of `struct device` instead of
`device_t` which is part of the public API. This patch changes all
`struct device *` to `device_t`.
The remaining occurrences of `struct device` are those referring to the
Linux or OpenBSD version of the structure, or the code is not built on
FreeBSD and it's unclear what to do.
Submitted by: Matthew Macy <mmacy@nextbsd.org> (previous version)
Approved by: emaste, jhibbits, sbruno
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D7447
_prison_check_ip4 renamed to prison_check_ip4_locked
Move IPv6-specific jail functions to new file netinet6/in6_jail.c
_prison_check_ip6 renamed to prison_check_ip6_locked
Add appropriate prototypes to sys/sys/jail.h
Adjust kern_jail.c to call prison_check_ip4_locked and
prison_check_ip6_locked accordingly.
Add netinet/in_jail.c and netinet6/in6_jail.c to the list of files that
need to be built when INET and INET6, respectively, are configured in the
kernel configuration file.
Reviewed by: jtl
Approved by: sjg (mentor)
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D6799
If the listening socket is closed while sonewconn() is executing, the
nascent child socket is aborted, which results in recursion on the
unp_link lock when the child's pru_detach method is invoked. Fix this
by using a flag to mark such sockets, and skip a part of the socket's
teardown during detach.
Reported by: Raviprakash Darbha <rdarbha@juniper.net>
Tested by: pho
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D7398
r296773 was done to only remove libc symbols for <7. We want to provide
the syscall symbols going forward for 7+.
Discussed with: jhb
MFC after: 3 days
Sponsored by: EMC / Isilon Storage Division
Our mprotect() function seems to take a "const void *" address to the
pages whose permissions need to be adjusted. POSIX uses "void *". Simply
stick to the POSIX one to prevent us from writing unportable code.
PR: 211423 (exp-run)
Tested by: antoine@ (Thanks!)
All current spinning loops retry an atomic op the first chance they get,
which leads to performance degradation under load.
One classic solution to the problem consists of delaying the test to an
extent. This implementation has a trivial linear increment and a random
factor for each attempt.
For simplicity, this first thouch implementation only modifies spinning
loops where the lock owner is running. spin mutexes and thread lock were
not modified.
Current parameters are autotuned on boot based on mp_cpus.
Autotune factors are very conservative and are subject to change later.
Reviewed by: kib, jhb
Tested by: pho
MFC after: 1 week
Both variables are uint64_t, but they only count spins or sleeps.
All reasonable values which we can get here comfortably hit in 32-bit range.
Suggested by: kib
MFC after: 1 week
