the countdown register.
this should not be necessary but there are broken laptops that
do not restore the countdown register on resume.
when it happnes, it messes up the hardclock interval and system clock,
which leads to the infamous "calcru: negative time" problem.
Submitted by: kjc, iwasaki
Reviewed by: Steve O'Hara-Smith <steveo@eircom.net> and committers.
Obtained from: PAO3
* Change the hack used on the alpha for mapping devices into DENSE or
BWX memory spaces to a simpler one. Its still a hack and should be
a seperate api to explicitly map the resource.
* Add $FreeBSD$ as necessary.
can provide the correct context to each signal handler.
Fix broken sigsuspend(): don't use p_oldsigmask as a flag, use SAS_OLDMASK
as we did before the linuxthreads support merge (submitted by bde).
Move ps_sigstk from to p_sigacts to the main proc structure since signal
stack should not be shared among threads.
Move SAS_OLDMASK and SAS_ALTSTACK flags from sigacts::ps_flags to proc::p_flag.
Move PS_NOCLDSTOP and PS_NOCLDWAIT flags from proc::p_flag to procsig::ps_flag.
Reviewed by: marcel, jdp, bde
o Remove unused defines from genassym.c that were needed
by the trampoline.
o Add load_gs_param function to support.s that catches
a fault when %gs is loaded with an invalid descriptor.
The function returns EFAULT in that case.
o Remove struct trapframe from mcontext_t and replace it
with the list of registers.
o Modify sendsig and sigreturn accordingly.
This commit contains a patch by bde.
Reviewed by: luoqi, jdp
struct sigcontext and ucontext_t/mcontext_t are defined in such
a way that both (ie struct sigcontext and ucontext_t) can be
passed on to sigreturn. The signal handler is still given a
ucontext_t for maximum flexibility.
For backward compatibility sigreturn restores the state for the
alternate signal stack from sigcontext.sc_onstack and not from
ucontext_t.uc_stack. A good way to determine which value the
application has set and thus which value to use, is still open
for discussion.
NOTE: This change should only affect those binaries that use
sigcontext and/or ucontext_t. In the source tree itself
this is only doscmd. Recompilation is required for those
applications.
This commit also fixes a lot of style bugs without hopefully
adding new ones.
NOTE: struct sigaltstack.ss_size now has type size_t again. For
some reason I changed that into unsigned int.
Parts submitted by: bde
sigaltstack bug found by: bde
-----------------------------
By introducing a new sigframe so that the signal handler operates
on the new siginfo_t and on ucontext_t instead of sigcontext, we
now need two version of sendsig and sigreturn.
A flag in struct proc determines whether the process expects an
old sigframe or a new sigframe. The signal trampoline handles
which sigreturn to call. It does this by testing for a magic
cookie in the frame.
The alpha uses osigreturn to implement longjmp. This means that
osigreturn is not only used for compatibility with existing
binaries. To handle the new sigset_t, setjmp saves it in
sc_reserved (see NOTE).
the struct sigframe has been moved from frame.h to sigframe.h
to handle the complex header dependencies that was caused by
the new sigframe.
NOTE: For the i386, the size of jmp_buf has been increased to hold
the new sigset_t. On the alpha this has been prevented by
using sc_reserved in sigcontext.
be set by a kernel conf option due to the struct buf structural
dependancy (sizing of b_pages[]) creating a conflict with modules
(which are not compiled with kernel config options overrides).
We'll be able to sysctl these two later on when the buffer subsystem
is revamped.
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.
1. Move definitions of struct i386_*_args to the header file sysarch.h,
since they are part of the sysarch API. struct i386_get_ldt_args and
i386_set_ldt_args were identical, therefore make them into one
struct i386_ldt_args. Libc should use these definitions as well.
2. Return a more sensible EOPNOTSUPP for unknown operations.
Reviewed by: marcel
into two parts - one to do the bsfl and the other to convert the result
(base 0) to ffs()-like (base 1) in inline C. This enables the optimizer
to be a lot smarter in certain cases, like where it knows that the argument
is non-zero and we want ffs(known non zero arg) - 1. This appears to
produce identical code to the old inline when the argument is unknown.
that are linked into the kernel. The KLD compilation options are
changed to call these functions, rather than in-lining the
atomic operations.
This approach makes atomic operations from KLDs significantly
faster on UP systems (though somewhat slower on SMP systems).
PR: i386/13111
Submitted by: peter.jeremy@alcatel.com.au
0x40 and then access data stored in real-mode segment 0x40, even when
called in protected mode. Microsoft unfortunately coddle these individuals,
and so must we if we want to run their code.
This change works around GPFs in some APM and PnP BIOS implementations.
Obtained from: Linux
- Add support for calling 32-bit code in other segments
- Add support for calling 16-bit protected mode code
Update APM to use this facility.
Submitted by: jlemon
equivalent to SYS_RES_MEMORY for x86 but for alpha, the rman_get_virtual()
address of the resource is initialised to point into either dense-mapped
or bwx-mapped space respectively, allowing direct memory pointers to be
used to device memory.
Reviewed by: Andrew Gallatin <gallatin@cs.duke.edu>
macros) to the signal handler, for old-style BSD signal handlers as
the second (int) argument, for SA_SIGINFO signal handlers as
siginfo_t->si_code. This is source-compatible with Solaris, except
that we have no <siginfo.h> (which isn't even mentioned in POSIX
1003.1b).
An rather complete example program is at
http://www3.cons.org/cracauer/freebsd-signal.c
This will be added to the regression tests in src/.
This commit also adds code to disable the (hardware) FPU from
userconfig, so that you can use a software FP emulator on a machine
that has hardware floating point. See LINT.
Change "void *" to "volatile TYPE *", improving type safety
and eliminating some warnings (e.g., mp_machdep.c rev 1.106).
cpufunc.h:
Eliminate setbits. As defined, it's not precisely correct;
and it's redundant. (Use atomic_set_int instead.)
ipl_funcs.c:
Use atomic_set_int instead of setbits.
systm.h:
Include atomic.h.
Reviewed by: bde
the caller to specify a function to be guarded between an entry and exit
barrier, as well as pre- and post-barrier functions.
The primary use for this function is synchronised update of per-cpu private
data. The implementation is almost (but not quite) MI; with a better
mechanism for masking per-CPU interrupts it could probably be hoisted.
Reviewed by: peter (partially)
with respect to interrupts on UP systems. (The upgrade from gcc 2.7.x
to egcs 1.1.2 produced at least one non-atomic code sequence in
swap_pager_getpages.)
In addition, the primitives are now SMP-safe, but only on SMPs. (For
portability between SMPs and UPs, modules are compiled with the SMP-safe
versions.)
Submitted by: dillon and myself
Reviewed by: bde
