write lock when doing PID allocation, and during the process exit path.
Use a read lock every where else, including within schedcpu() (interrupt
context). Note that holding the write lock implies blocking schedcpu()
from running (blocks softclock).
PID allocation is now MP-safe.
Note this actually fixes a bug on single processor systems that was probably
extremely difficult to tickle; it was possible that schedcpu() would run
off a bad pointer if the right clock interrupt happened to come in the
middle of a LIST_INSERT_HEAD() or LIST_REMOVE() to/from allproc.
and PID allocation MP-safe. A new process state is added: SDEAD. This
state indicates that a process is dead, but not yet a zombie (has not
yet been processed by the process reaper).
SDEAD processes exist on both the zombproc list (via p_list) and deadproc
(via p_hash; the proc has been removed from the pidhash earlier in the exit
path). When the reaper deals with a process, it changes the state to
SZOMB, so that wait4 can process it.
Add a P_ZOMBIE() macro, which treats a proc in SZOMB or SDEAD as a zombie,
and update various parts of the kernel to reflect the new state.
which use uvm_vslock() should now test the return value. If it's not
KERN_SUCCESS, wiring the pages failed, so the operation which is using
uvm_vslock() should error out.
XXX We currently just EFAULT a failed uvm_vslock(). We may want to do
more about translating error codes in the future.
vslocking here?! copyout() on its own seems to suffice just about everwhere
else, and it's not like the process is going to exit; it's in a system
call!
* availability of POSIX Synchronized I/O (kern.synchronized_io),
* maximum number of iovec structures to be used in readv(2) etc. (kern.iov_max)
via sysctl().
(thus causing s_leader to become NULL) by storing the session ID separately
in the session structure. Export the session ID to userspace in the
eproc structure.
Submitted by Tom Proett <proett@nas.nasa.gov>.
UVM was written by chuck cranor <chuck@maria.wustl.edu>, with some
minor portions derived from the old Mach code. i provided some help
getting swap and paging working, and other bug fixes/ideas. chuck
silvers <chuq@chuq.com> also provided some other fixes.
this is the rest of the MI portion changes.
this will be KNF'd shortly. :-)
msgbuf. Note that old 'dmesg' and 'syslogd' binaries will continue running,
though old 'dmesg' binaries will output a few bytes of junk at the start of
the buffer, and will miss a few bytes at the end of the buffer.
__VM_PMAP_HACK is defined (for temporary compatibility).
The __VM_PMAP_HACK code should be removed after all the
ports that define it have removed all vm_pmap references.
Eliminate obsolete global kernel variable "struct timezone tz"
Add RTC_OFFSET option
Add global kernel variable rtc_offset, which is initialized by
RTC_OFFSET at kernel compile time.
on i386, x68k, mac68k, pc532 and arm32, RTC_OFFSET indicates how many
minutes west (east) of GMT the hardware RTC runs. Defaults to 0.
Places where tz variable was used to indicate this in the past have
been replaced with rtc_offset.
Add sysctl interface to rtc_offset.
Kill obsolete DST_* macros in sys/time.h
gettimeofday now always returns zeroed timezone if zone is requested.
settimeofday now ignores and logs attempts to set non-existant kernel
timezone.
documented behavior. sysctl(3) is documented to return 0 on success,
-1 on failure. The previous behavior was to return -1 on failure
and the number of bytes copied back down to user space.
Fixes part of PR #1999, from Kevin M. Lahey <kml@nas.nasa.gov>
and the "kernel.tar.Z" distribution on louie.udel.edu, which is older than
xntp 3.4y or 3.5a, but contains newer kernel source fragments.
This commit adds support for a new kernel configuration option, NTP.
If NTP is selected, then the system clock should be run at "HZ", which
must be defined at compile time to be one value from:
60, 64, 100, 128, 256, 512, 1024.
Powers of 2 are ideal; 60 and 100 are supported but are marginally less
accurate.
If NTP is not configured, there should be no change in behavior relative
to pre-NTP kernels.
These changes have been tested extensively with xntpd 3.4y on a decstation;
almost identical kernel mods work on an i386. No pulse-per-second (PPS)
line discipline support is included, due to unavailability of hardware
to test it.
With this in-kernel PLL support for NetBSD, both xntp 3.4y and xntp
3.5a user-level code need minor changes. xntp's prototype for
syscall() is correct for FreeBSD, but not for NetBSD.
thorpej