- this patch fixes a deadlock which may occur if we get a
spurious interrupt while calibrating clocks during the boot
time. Since we never handle interrupts while in the kernel
(BKL locked) the interrupt code locks the lock. This is a
different situation, a corner case, boot time only. We do not
return to userspace but to the kernel, so the BKL is not
unlocked. So we need irq handler which leaves the BKL
unlocked. The clock handler does it already, this patch adds
a dummy spurious irq handler for the same reason. It is better
to handle the situation this way to keep the normal runtime
code simple.
- this is a temporary change which makes images compiled for SMP
boot in SMP mode by default.
- this change is needed until we can configure the multiboot
images from the boot loader again.
User processes can send signals with number up to _NSIG. There are a few
signal numbers above that used by the kernel, but should explicitly not
be included in the range or range checks in PM will fail.
The system processes use a different version of sigaddset, sigdelset,
sigemptyset, sigfillset, and sigismember which does not include a range
check on signal numbers (as opposed to the normal functions used by normal
processes).
This patch unbreaks test37 when the boot image is compiled with GCC/Clang.
- we must not deliver messages from/to unstable address spaces.
In such a case, we must postpone the delivery. To make sute
that a process which is expecting an asynchronous message does
not starve, we must remember that we skipped delivery of some
messages and we must try to deliver again once the source
address space is stable again.
- when kernel copies from userspace, it must be sure that the TLB
entries are not stale and thus the referenced memory is correct
- everytime we change a process' address space we set p_stale_tlb
bits for all CPUs.
- Whenever a cpu finds its bit set when it wants to access the
process' memory, it refreshes the TLB
- it is more conservative than it needs to be but it has low
overhead than checking precisely
- two CPUs can issue IPI to each other now without any hazzard
- we must be able to handle synchronous scheduling IPIs from
other CPUs when we are waiting for attention from another one.
Otherwise we might livelock.
- necessary barriers to prevent reordering
- has_pending() takes a special argument that tells the code
whether we are scanning for asynchronous message or something
else.
- has_pending() is not used directly anymore
- the new functions are wrappings around has_pending() to make
the use more comfortable.
- these functions should become static inline eventually
Remove .ident sections, and force separations of .text and
.data sections into separate program headers, for the benefit
of the check done by MINIX boot monitor in multiboot mode.
. workaround for clang's stdint.h __STDC_HOSTED__ test
that causes the host stdint.h to be ignored for -ffreestanding,
causing a type to be double-defined in the kernel
. only use for single-page invalidations initially
. shows tiny but statistically significant performance
improvement; will be more helpful in certain VM debug
modes
. fold 2 exception-in-kernel cases (pagefault and rest)
into 1
. for exceptions that occur in kernel, don't just print
kernel stacktrace (typically that is just the exception
handler) but also the stacktrace of when the exception
happened
