from the NFS server, following contention on a lock by this or another
client, immediately notify the waiting process that the lock has been
granted via a wakeup. Without this change, the client rpc.lockd will
not wakeup the waiting process until it next re-polls the lock (sometime
in the next ten seconds), which can lead to marked latency across all
potential lockers, as the lock is held by the client for the duration.
Approved by: re (scottl)
Submitted by: truckman
Reviewed by: Andrew P. Lentvorski, Jr <bsder@allcaps.org>
stolen from the ia64/ia32 code (indeed there was a repocopy), but I've
redone the MD parts and added and fixed a few essential syscalls. It
is sufficient to run i386 binaries like /bin/ls, /usr/bin/id (dynamic)
and p4. The ia64 code has not implemented signal delivery, so I had
to do that.
Before you say it, yes, this does need to go in a common place. But
we're in a freeze at the moment and I didn't want to risk breaking ia64.
I will sort this out after the freeze so that the common code is in a
common place.
On the AMD64 side, this required adding segment selector context switch
support and some other support infrastructure. The %fs/%gs etc code
is hairy because loading %gs will clobber the kernel's current MSR_GSBASE
setting. The segment selectors are not used by the kernel, so they're only
changed at context switch time or when changing modes. This still needs
to be optimized.
Approved by: re (amd64/* blanket)
- Move struct sigacts out of the u-area and malloc() it using the
M_SUBPROC malloc bucket.
- Add a small sigacts_*() API for managing sigacts structures: sigacts_alloc(),
sigacts_free(), sigacts_copy(), sigacts_share(), and sigacts_shared().
- Remove the p_sigignore, p_sigacts, and p_sigcatch macros.
- Add a mutex to struct sigacts that protects all the members of the struct.
- Add sigacts locking.
- Remove Giant from nosys(), kill(), killpg(), and kern_sigaction() now
that sigacts is locked.
- Several in-kernel functions such as psignal(), tdsignal(), trapsignal(),
and thread_stopped() are now MP safe.
Reviewed by: arch@
Approved by: re (rwatson)
don't add the current time to it, but leave it as clear so that when the
timer is disabled, the it_value is always clear.
Reviewed by: bde
Approved by: re (rwatson)
Those who really need this information can find it in the include file.
* Include a succinct description of the st_birthtime field.
Approved by: re (bmah)
desired buffer is found at one of the roots more than 60% of the time.
Thus, checking both roots before performing either splay eliminates
unnecessary splays on the first tree splayed.
Approved by: re (jhb)
- hosts_ctl(3), hosts_access(3), request_init(3),
request_set(3).
PR: docs/52000
Submitted by: Simon L. Nielsen <simon@nitro.dk>
Approved and Reviewed by: des (mentor), re (scottl)
was obtained from [1], with heavy editing, and ammending text for some of
the ioctls.
All ioctls (in sys/agpio.h) are now documented.
PR: docs/50503
Original patch by: Alex Semenyaka <alexs@snark.ratmir.ru> [1]
Content approved by:
- Eric Anholt <anholt@FreeBSD.ORG>
- Matthew N. Dodd <mdodd@FreeBSD.ORG> (cursory review)
Approved and Reviewed by: des (mentor), re (scottl)
etc.) from the application namespace for programs that use pam_ssh(8).
Use #defines to avoid changing the actual source code.
Approved by: re (rwatson)
we do not have to run so long with interrupts disabled. This involved
creating tf_addr in the trapframe. Reorganize the trap stubs so that
they consistently reserve the stack space and initialize any missing
bits.
Approved by: re (amd64 stuff)
by using a __packed keyword for the fxp_rfa structure. The Intel
guys who designed this structure with unaligned fields deserve
to be shot.
Tested by: kris
Approved by: re@ (jhb)
synchronization primitives from inside DDB is generally a bad idea,
and in this case it frequently results in panics due to DDB commands
being executed from the sio fast interrupt context on a serial
console. Replace the locking with a note that a lack of locking
means that DDB may get see inconsistent views of the mount and vnode
lists, which could also result in a panic. More frequently,
though, this avoids a panic than causes it.
Discussed with ages ago: bde
Approved by: re (scottl)
Correct reversed variable assignments.
Re-enable the call to _mutex_lock_backout(). This might
need revisiting once internal locking of mutex and cv is done.
Approved by: markm/mentor, re/blanket libthr
Reviewed by: jeff
Make state transitions of a thread on a mutex queue
atomic (with respect to other threads and signal handlers).
This includes:
o Introduce two functions to implement atomicity with respect
to other threads and signal handlers. Basically,
_thread_critical_enter() locks the calling thread and blocks
signals. _thread_critical_exit() unblocks signals and unlocks
the thread.
o Introduce two new functions:
get_muncontested() locks a mutex that is not owned by
another thread.
get_mcontested() places a thread on a contested mutex's
queue, taking care to use the _thread_critical_enter/exit
functions to protect thread state.
o Modify mutex_unlock_common() to also protect state transitions.
In this case it needs the cooperation of mutex_queue_deq(), which
must return with the thread locked and signals disabled *before*
it takes the thread off the queue.
Combine _pthread_mutex_lock() and _pthread_mutex_trylock()
into one function: mutex_lock_common(), that can handle
both cases. Its behaviour is controlled by an argument,
int nonblock, which if not zero means do not attempt
to acquire a contested mutex if the uncontested case fails.
BTW, when I write about contested and uncontested mutexes, I'm writing
about it from the application's point of view. I'm not writing about
internal locking of pthread_mutex->lock, which is achieved differently.
While internal mutex locking is mostly done, there's still a bit more
work left in this area.
Approved by: markm/mentor, re/blanket libthr
Reviewed by: jeff (slightly diff. revision)
common code, the non-trivial part is #ifdef'ed and only executes when
loading amd64 kernels. The rest is trivial but needed for the the amd64
case. (Two variables changed from char ** to Elf_Addr).
Approved by: re (amd64 "low-risk" stuff)
bus_dma MD code for AMD64. (And a trivial ifdef update in dev/kbd because
of this). More updates are needed here to take advantage of the 64 bit
instructions.
Approved by: re (blanket amd64/*)
