flags field. Updates to the atomic flags are performed using the atomic
ops on the containing word, do not require any vm lock to be held, and
are non-blocking. The vm_page_aflag_set(9) and vm_page_aflag_clear(9)
functions are provided to modify afalgs.
Document the changes to flags field to only require the page lock.
Introduce vm_page_reference(9) function to provide a stable KPI and
KBI for filesystems like tmpfs and zfs which need to mark a page as
referenced.
Reviewed by: alc, attilio
Tested by: marius, flo (sparc64); andreast (powerpc, powerpc64)
Approved by: re (bz)
improvements:
(1) Implement new model in previously missed at91 UART driver
(2) Move BREAK_TO_DEBUGGER and ALT_BREAK_TO_DEBUGGER from opt_comconsole.h
to opt_kdb.h (spotted by np)
(3) Garbage collect now-unused opt_comconsole.h
MFC after: 3 weeks
Approved by: re (bz)
accessible:
(1) Always compile in support for breaking into the debugger if options
KDB is present in the kernel.
(2) Disable both by default, but allow them to be enabled via tunables
and sysctls debug.kdb.break_to_debugger and
debug.kdb.alt_break_to_debugger.
(3) options BREAK_TO_DEBUGGER and options ALT_BREAK_TO_DEBUGGER continue
to behave as before -- only now instead of compiling in
break-to-debugger support, they change the default values of the
above sysctls to enable those features by default. Current kernel
configurations should, therefore, continue to behave as expected.
(4) Migrate alternative break-to-debugger state machine logic out of
individual device drivers into centralised KDB code. This has a
number of upsides, but also one downside: it's now tricky to release
sio spin locks when entering the debugger, so we don't. However,
similar logic does not exist in other device drivers, including uart.
(5) dcons requires some special handling; unlike other console types, it
allows overriding KDB's own debugger selection, so we need a new
interface to KDB to allow that to work.
GENERIC kernels in -CURRENT will now support break-to-debugger as long as
appropriate boot/run-time options are set, which should improve the
debuggability of BETA kernels significantly.
MFC after: 3 weeks
Reviewed by: kib, nwhitehorn
Approved by: re (bz)
to VPO_UNMANAGED (and also making the flag protected by the vm object
lock, instead of vm page queue lock).
- Mark the fake pages with both PG_FICTITIOUS (as it is now) and
VPO_UNMANAGED. As a consequence, pmap code now can use use just
VPO_UNMANAGED to decide whether the page is unmanaged.
Reviewed by: alc
Tested by: pho (x86, previous version), marius (sparc64),
marcel (arm, ia64, powerpc), ray (mips)
Sponsored by: The FreeBSD Foundation
Approved by: re (bz)
o Fix awkward use of braces in combination with mis-indentation.
A mistake, that happened to yield the right behaviour?
o Fix typo in comment.
No functional change.
Approved by: re (blanket)
Juniper's loader is that Juniper's loader maps all of the kernel and
preloaded modules at the right virtual address before jumping into the
kernel. FreeBSD's loader simply maps 16MB using the physical address
and expects the kernel to jump through hoops to relocate itself to
it's virtual address. The problem with the FreeBSD loader's approach is
that it typically maps too much or too little. There's no harm if it's
too much (other than wasting space), but if it's too little then the
kernel will simply not boot, because the first thing the kernel needs
is the bootinfo structure, which is never mapped in that case. The page
fault that early is fatal.
The changes constitute:
1. Do not remap the kernel in locore.S. We're mapped where we need to
be so we can pretty much call into C code after setting up the
stack.
2. With kernload and kernload_ap not set in locore.S, we need to set
them in pmap.c: kernload gets defined when we preserve the TLB1.
Here we also determine the size of the kernel mapped. kernload_ap
is set first thing in the pmap_bootstrap() method.
3. Fix tlb1_map_region() and its use to properly externd the mapped
kernel size to include low-level data structures.
Approved by: re (blanket)
Obtained from: Juniper Networks, Inc
event of a broken or busy fan due to returning incorrect error codes from
the FCU sysctl handler.
Reported by: Path Mather <paul at gromit dot dlib dot vt dot edu>1
Approved by: re (kib)
This patch is going to help in cases like mips flavours where you
want a more granular support on MAXCPU.
No MFC is previewed for this patch.
Tested by: pluknet
Approved by: re (kib)
sintrcnt/sintrnames which are symbols containing the size of the 2
tables.
- For amd64/i386 remove the storage of intr* stuff from assembly files.
This area can be widely improved by applying the same to other
architectures and likely finding an unified approach among them and
move the whole code to be MI. More work in this area is expected to
happen fairly soon.
No MFC is previewed for this patch.
Tested by: pluknet
Reviewed by: jhb
Approved by: re (kib)
packets. It turns out that all firmware versions insert it, whether or not
they support VLAN tagging.
Submitted by: glevand <geoffrey.levand at mail dot ru>
machine checks (e.g. invalid PCI configuration cycles), but these can
be caught and recovered from. This change also the RTAS PCI driver to
work without modification as a replacement for the Grackle driver on
Grackle-based Powermacs.
smell that caused me to turn this up was due to a failed fan burning, not
a CPU (plus a healthy dose of paranoia).
Submitted by: Paul Mather <paul at gromit dot dlib dot vt dot edu>
instead of a PCPU field for curthread. This averts a race on SMP systems
with a high interrupt rate where the thread looking up the value of
curthread could be preempted and migrated between obtaining the PCPU
pointer and reading the value of pc_curthread, resulting in curthread being
observed to be the current thread on the thread's original CPU. This played
merry havoc with the system, in particular with mutexes. Many thanks to
jhb for helping me work this one out.
Note that Book-E is in principle susceptible to the same problem, but has
not been modified yet due to lack of Book-E hardware.
MFC after: 2 weeks
some interesting bugs (mostly on SMP systems) with atomic operations
silently failing in interrupt heavy situations, especially when using
overflow pages.
(obvious in retrospect) in which interrupts on one CPU that are temporarily
masked can end up permanently masked when a handler on another CPU clobbers
the interrupt mask register with an old copy.
the future, but presents a set of simple block devices for now. With
(forthcoming) boot loader support or vfs.root.mountfrom, allows booting
PS3s from disk.
Submitted by: glevand <geoffrey.levand@mail.ru>
pmap_sync_icache() to sync random (possibly uncached or nonexisting!)
memory, causing kernel page faults or machine checks, most easily
triggered by using GDB. While here, add an additional safeguard to only
sync cacheable memory.
MFC after: 2 days
