in a separate word from the _count. This does not permit both items to
be updated atomically in a portable manner. As a result, sem_post()
must always perform a system call to safely clear _has_waiters.
This change removes the _has_waiters field and instead uses the high bit
of _count as the _has_waiters flag. A new umtx object type (_usem2) and
two new umtx operations are added (SEM_WAIT2 and SEM_WAKE2) to implement
these semantics. The older operations are still supported under the
COMPAT_FREEBSD9/10 options. The POSIX semaphore API in libc has
been updated to use the new implementation. Note that the new
implementation is not compatible with the previous implementation.
However, this only affects static binaries (which cannot be helped by
symbol versioning). Binaries using a dynamic libc will continue to work
fine. SEM_MAGIC has been bumped so that mismatched binaries will error
rather than corrupting a shared semaphore. In addition, a padding field
has been added to sem_t so that it remains the same size.
Differential Revision: https://reviews.freebsd.org/D961
Reported by: adrian
Reviewed by: kib, jilles (earlier version)
Sponsored by: Norse
It had two bugs: one where mmap was still allowed and another where
D_TRACKCLOSE doesn't handle all cases.
Thanks to jhb and kib for pointing them out.
MFC after: 1 week
the map count and without being able to keep track of the current map
allocation, bus_dma_tag_destroy() will fail to proceed and will return
EBUSY even after all the maps have been correctly destroyed with
bus_dmamap_destroy().
Found while testing the detach method of a NIC.
Tested on: BBB (am335x)
Reviewed by: cognet, ian
MFC after: 1 week
In some cases, TSC is broken and special applications might benefit
from memory mapping HPET and reading the registers to count time.
Most often the main HPET counter is 32-bit only[1], so this only gives
the application a 300 second window based on the default HPET
interval.
Other applications, such as Intel's DPDK, expect /dev/hpet to be
present and use it to count time as well.
Although we have an almost userland version of gettimeofday() which
uses rdtsc in userland, it's not always possible to use it, depending
on how broken the multi-socket hardware is.
Install the acpi_hpet.h so that applications can use the HPET register
definitions.
[1] I haven't found a system where HPET's main counter uses more than
32 bit. There seems to be a discrepancy in the Intel documentation
(claiming it's a 64-bit counter) and the actual implementation (a
32-bit counter in a 64-bit memory area).
MFC after: 1 week
Relnotes: yes
- Poke at VM_MIN_ADDRESS in machine/vmparam.h because FreeBSD doesn't have a
vm.minaddress sysctl analog
- Expect ENOMEM instead of EAGAIN in mlock_limits
- Provide mlock an mmap'ed page twice to simulate MAP_WIRED on NetBSD
In collaboration with: pho
Sponsored by: EMC / Isilon Storage Division
- getrusage_utime_back succeeds reliably on FreeBSD
- getrusage_utime_zero passes/fails in a seemingly non-deterministic manner.
Skip it for now (and fix it later)
In the initial port of this testcase to FreeBSD, the results failed reliably
in the same manner as it does on NetBSD
Sponsored by: EMC / Isilon Storage Division
Place the code introduced in r268660 into a separate function that can be
called from uiomove_fromphys. Instead of pre-allocating two KVA pages use
vmem_alloc to allocate them on demand when needed. This prevents blocking if
a page fault is taken while physical addresses from outside the DMAP are
used, since the lock is now removed.
Also introduce a safety catch in PHYS_TO_DMAP and DMAP_TO_PHYS.
Sponsored by: Citrix Systems R&D
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D947
amd64/amd64/pmap.c:
- Factor out the code to deal with non DMAP addresses from pmap_copy_pages
and place it in pmap_map_io_transient.
- Change the code to use vmem_alloc instead of a set of pre-allocated
pages.
- Use pmap_qenter and don't pin the thread if there can be page faults.
amd64/amd64/uio_machdep.c:
- Use pmap_map_io_transient in order to correctly deal with physical
addresses not covered by the DMAP.
amd64/include/pmap.h:
- Add the prototypes for the new functions.
amd64/include/vmparam.h:
- Add safety catches to make sure PHYS_TO_DMAP and DMAP_TO_PHYS are only
used with addresses covered by the DMAP.
- Expect ENOMEM instead of EFAULT when msync'ing a previously munmap'ed region
on FreeBSD
Submitted by: pho
Sponsored by: EMC / Isilon Storage Division
* Use a constant to define the number of stack frames in a probe exception.
* Only allow function symbols in powerpc64 ('.' prefixed)
* Set the fbtp_roffset for return probes, so the correct dtrace_probe call is
made.
MFC after: 1 week
indiscriminately to printf() and freeenv() is incorrect. Add a NULL
check before freeenv(); as for printf(), we could use req.newptr
instead, but we'd have to select the correct format string based on
the type, and that's too much work for an error message, so just
remove it.
workaround for an imx6 chip erratum. Linux works around the bug with
changes in fdt data that we can't currently handle, so to enable running
with standard vendor-supplied fdt data, this watches for an attempt to map
the gpio1_6 interrupt and remaps it back to the standard ethernet interrupt.
This can be undone when the intrng project is completed and our gpio drivers
can also be interrupt controllers.
search (i.e. without returning any result) and you would end up with a
random MAC address.
Change the search algorithm to a recursive one to ensure that all the nodes
on DTS will be verified.
The previous algorithm could not keep up if the DTS has too many sub-nodes.
While here, fix the punctuation on comments.
To restore the default font using vidcontrol(1), use the "-f" flag
without an argument:
vidcontrol -f < /dev/ttyv0
PR: 193910
Differential Revision: https://reviews.freebsd.org/D971
Submitted by: Marcin Cieslak <saper@saper.info>
Reviewed by: ray@, emaste@
Approved by: ray@
MFC after: 1 week
