but it's better than the buggy behavior we have now. If we contigmalloc()
buffers in bus_dmamem_alloc(), then we must configfree() them in
bus_dmamem_free(). Trying to free() them is wrong, and will cause
a panic (at least, it does on the alpha.)
I tripped over this when trying to kldunload my busdma-ified if_rl
driver.
to see if it was malloc()ed first" bug. In bus_dmamap_create(), one of
two things can happen: either we need to allocate a special map due to
some manner of bounce buffering requirement, or we can DMA a buffer
in place. On the x86 platform, the "in place" case results in
bus_dmamap_create() returning a dmamap of NULL. The bus_dmamap_destroy()
routine later checks for NULL and won't bother free()ing the map if
it detects this condition.
But on the alpha, we don't use NULL, we use a statically allocated map
called nobounce_dmamap(). Unfortunately, bus_dmamap_destroy() does not
handle the condition where we attempt to destroy such a map: it tries
to free() the dmamap, which causes a panic.
Fix: test that map != &nobounce_dmamap before trying to free() it.
With this fix, my busdma-ified if_sis driver works on the alpha. I'm
a bit alarmed that I'm the first person ever to trip over this bug, since
we have been using busdma on the alpha for a while, and since it sort
of screams out "Hi! I'm a bug! Booga-booga!" when you look at it.
(Somewhere, somebody will say: "But Bill, why don't you just not bother
destroying the maps in this case." Because the API is supposed to be
a) symetrical and b) opaque to the caller. I can't know whether it's safe
to skip the bus_dmamap_destroy() step or not without sticking my fingers
into unsafe places, which is what I wanted to avoid in the first place.)
boot CPU. This was the reason reboots on SMP systems could result in
weird hangs. Unlike the x86, we do not need to switch back to the boot
CPU in order to reboot the machine. See Section 3.4.5 of Part III
(Console Interface Architecture) from the Alpha Architecture Reference
Manual (aka the Brown Book) for more info.
the process of exiting the kernel. The ast() function now loops as long
as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with
preemption disabled so that any further AST's that arrive via an
interrupt will be delayed until the low-level MD code returns to user
mode.
- Use u_int's to store the tick counts for profiling purposes so that we
do not need sched_lock just to read p_sticks. This also closes a
problem where the call to addupc_task() could screw up the arithmetic
due to non-atomic reads of p_sticks.
- Axe need_proftick(), aston(), astoff(), astpending(), need_resched(),
clear_resched(), and resched_wanted() in favor of direct bit operations
on p_sflag.
- Fix up locking with sched_lock some. In addupc_intr(), use sched_lock
to ensure pr_addr and pr_ticks are updated atomically with setting
PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing
PS_OWEUPC. We also do not grab the lock just to test a flag.
- Simplify the handling of Giant in ast() slightly.
Reviewed by: bde (mostly)
are a really nasty interface that should have been killed long ago
when 'ptrace(PT_[SG]ETREGS' etc came along. The entity that they
operate on (struct user) will not be around much longer since it
is part-per-process and part-per-thread in a post-KSE world.
gdb does not actually use this except for the obscure 'info udot'
command which does a hexdump of as much of the child's 'struct user'
as it can get. It carries its own #defines so it doesn't break
compiles.
dynamic symbol table buckets and chains. The sparc64 toolchain uses 32
bit .hash entries, unlike other 64 bits architectures (alpha), which use
64 bit entries.
Discussed with: dfr, jdp
were indices in a dense array. The cpuids are a sparse set and treat
them as such, setting up containers only for CPUs activated during
mb_init().
- Fix netstat(1) and systat(1) to treat the per-CPU stats area as a sparse
map, in accordance with the above.
This allows us to properly boot with certain CPUs disactivated. However, if
we later decide to re-activate said CPUs, we will barf until we decide to
implement CPU spinon/spinoff callback hooks to allow for said CPUs' per-CPU
containers to get configured on their activation.
Reported by: mjacob
Partially (sys/ diffs) Submitted by: mjacob
simply manipulates the pte which faulted instead of traversing the mapping
list for that page. This makes it possible to complete the trap without
needing locks and incidentally improves the accuracy of some statistics
used by the VM system.
blown over by the Hurricane and had a house dropped on you by the Tornado.
Now it's time to have your parade rained on by... the Typhoon!
This commit adds driver support for 3Com 3cR990 10/100 ethernet
adapters based on the Typhoon I and Typhoon II chipsets. This is actually
a port of the OpenBSD driver with many hacks by me.
No Virginia, there isn't any support for the hardware crypto yet. However
there is support for TCP/IP checksum offload and VLANs.
Special thanks go to Jason Wright, Aaron Campbell and Theo de Raadt for
squeezing enough info out of 3Com to get this written, and for doing
most of the hard work.
Manual page is included. Compiled as a module and included in GENERIC.
sure when things got so bad (JHB says preemption worked just fine for months
before the AlbertVM commit). Even post DillionVM locking commit, Miatas
(DEC Personal Workstations) are very fragile -- not making it thru a world
build. With this patch it does.
Those hacking on SMPng will want to locally back out this commit. The rest
of us will want to run with it until the SMPng guys figure out the problem(s).
Submitted by: peter
on Alpha 4100s.
Basically, if you're halting or you're rebooting, you should
tell all other processors to halt first. Define IPI_HALT- IPI_STOP
is not what we want for this purpose, which will call prom_halt(0)
on receipt.
The processor running the halt or reboot wil send an IPI_HALT to all
other processors, delay a bit, then continue to do what what it was
planning on doing (prom_halt({0|1})).
By default, we will end up with a duplicate set of hints if people have
a properly populated /boot/device.hints. So for now, remove the hints
here until Peter revisits the new hints processing from mid-June that
broke Alpha booting.
'dwatch'. The new commands install hardware watchpoints if supported
by the architecture and if there are enough registers to cover the
desired memory area.
No objection by: audit@, hackers@
MFC after: 2 weeks
Also removed some spl's and added some VM mutexes, but they are not actually
used yet, so this commit does not really make any operational changes
to the system.
vm_page.c relates to vm_page_t manipulation, including high level deactivation,
activation, etc... vm_pageq.c relates to finding free pages and aquiring
exclusive access to a page queue (exclusivity part not yet implemented).
And the world still builds... :-)
(this commit is just the first stage). Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
.cvsignore file for [A-Za-z]* to keep these directories around rather
than waste a file on .keepme. This should also make people's built
trees place nice with CVS.
Idea for .cvsignore: peter (although I suggested the regexp)
Pointed out by: Makoto MATSUSHITA-san <matusita@jp.FreeBSD.org>
Llama's costuming by: Fernamdo Llamas
vm_page_t's.
- Add a KTR_TRAP tracepoint to trap() on the alpha that displays the
contents of a0, a1, and a2 to make debugging of nested traps that
panic before displaying any useful output easier.
