spaces which cross a segment boundry in the page table. pmap_kextract()
is not designed for access to the user space portion of the page
table and cannot handle the null-page-directory-entry case.
The fix is to have vm_fault_quick() return a success or failure which
is then used to avoid calling pmap_kextract().
It is about 2.5 microseconds or roughly 3 times faster to use this
"PIIX" timecounter than the "i8254" timecounter. Resolution is
also 3 times better.
The code cheats and don't register the PCI device, because other pieces
of code want to use it too.
Originally spotted by: msmith
far-reaching in fd-land, so you'll want to consult the code for
changes. The biggest change is that now, you don't use
fp->f_ops->fo_foo(fp, bar)
but instead
fo_foo(fp, bar),
which increments and decrements the fp refcount upon entry and exit.
Two new calls, fhold() and fdrop(), are provided. Each does what it
seems like it should, and if fdrop() brings the refcount to zero, the
fd is freed as well.
Thanks to peter ("to hell with it, it looks ok to me.") for his review.
Thanks to msmith for keeping me from putting locks everywhere :)
Reviewed by: peter
users have suffered from this breakage, w/o commitment from someone that
they would fix the problems.
This effectively backs out revs 1.{157-160}. It does however fix the
build problem that caused 1.157 to be committed.
If the changes from rev 1.156-1.160 can't be fully tested by the
committer, may I offer posting a diff in the freebsd-current mailing
list for broader testing before inflicting this breakage again.
1) Reworked the probe routine
2) Addition of the 574B's product ID.
3) Added useful info when booting verbosely.
Submitted by: Jason Young <doogie@anet-stl.com>
warnings caused by the arg having the wrong type (not const enough).
The arg was also wrong (a full name instead of a short one) for calls
from from subr_diskmbr.c and pc98/diskslice_machdep.c.
random-seekable devices. This lets dd(1) know it can seek on them. It
also affects spec_vnopen() (IIRC), but only makes the path of execution smaller,
and does not change its behavior. This is when securelevel >= 2.
the OS does FXSAVE/FXRESTOR instructions (fast FPU save/restore) during
context switching and also enables SIMD since this enables saving the
extra CPU context that isn't saved with normal FPU regs. The other
enables the SIMD instructions to use exception 16 (FPU) error reporting.
Note, this doesn't turn on SIMD, just defines the bits.
return (in signal trampoline code). I plan to do the same on -stable,
so that we have a consistent interface to userland applications.
Reviewed by: bde