everything is contained inside #ifdef VM86, so this option must be
present in the config file to use this functionality.
Thanks to Tor Egge, these changes should work on SMP machines. However,
it may not be throughly SMP-safe.
Currently, the only BIOS calls made are memory-sizing routines at bootup,
these replace reading the RTC values.
interrupts are masked, and EOI is sent iff the corresponding ISR bit
is set in the local apic. If the CPU cannot obtain the interrupt
service lock (currently the global kernel lock) the interrupt is
forwarded to the CPU holding that lock.
Clock interrupts now have higher priority than other slow interrupts.
- A nonprofiling version of s_lock (called s_lock_np) is used
by mcount.
- When profiling is active, more registers are clobbered in
seemingly simple assembly routines. This means that some
callers needed to save/restore extra registers.
- The stack pointer must have space for a 'fake' return address
in idle, to avoid stack underflow.
region protected by the simplelock 'cpl_lock'.
Notes:
- this code is currently controlled on a section by section basis with
defines in machine/param.h. All sections are currently enabled.
- this code is not as clean as I would like, but that can wait till later.
- the "giant lock" still surrounds most instances of this "cpl region".
I still have to do the code that arbitrates setting cpl between the
top and bottom halves of the kernel.
- the possibility of deadlock exists, I am committing the code at this
point so as to exercise it and detect any such cases B4 the "giant lock"
is removed.
Several new fine-grained locks.
New FAST_INTR() methods:
- separate simplelock for FAST_INTR, no more giant lock.
- FAST_INTR()s no longer checks ipending on way out of ISR.
sio made MP-safe (I hope).
Work done by BSDI, Jonathan Lemon <jlemon@americantv.com>,
Mike Smith <msmith@gsoft.com.au>, Sean Eric Fagan <sef@kithrup.com>,
and probably alot of others.
Submitted by: Jnathan Lemon <jlemon@americantv.com>
- s_lock_init()
- s_lock()
- s_lock_try()
- s_unlock()
Created lock for IO APIC and apic_imen (SMP version of imen)
- imen_lock
Code to use imen_lock for access from apic_ipl.s and apic_vector.s.
Moved this code *outside* of mp_lock.
It seems to work!!!
that lkm's can use them for fiddling the masks without being dependent on
which mode the kernel is compiled in (SMP or UP). This is particularly
for ppp_tty.c which has some domain crossing between the net and tty
subsystems. The values are not used in the spl code, they are for
reference only (ie: the compiled code uses immediate values rather than
an indirect 32 bit address and 32 bit data fetch).
- vector.s <- stub called by i386/exception.s
- icu_vector.s <- UP
- apic_vector.s <- SMP
Split icu.s into UP and SMP specific files:
- ipl.s <- stub called by i386/exception.s (formerly icu.s)
- icu_ipl.s <- UP
- apic_ipl.s <- SMP
This was done in preparation for massive changes to the SMP INTerrupt
mechanisms. More fine tuning, such as merging ipl.s into exception.s,
may be appropriate.
