The removed argument could trivially be derived from the remaining one.
That in turn should be the same as curthread, but it is possible that curthread could be expensive to derive on some syste,s so leave it as an argument.
Having both proc and thread as an argumen tjust gives an opportunity for
them to get out sync.
MFC after: 3 days
in diagnostics. It has outlived its usefulness and has started
causing panics for people who turn on DIAGNOSTIC, in what is otherwise
good code.
MFC after: 2 days
do not set the virtual address to the bus address when the bus
doesn't have either of the PCI_RF_DENSE or PCI_RF_BWX flags set.
The TGA driver uses the virtual address to access the registers,
which on some machines can cause a memory management fault. Map
the bus address as K0SEG virtual memory instead. Note that with
some hardware combinations involving the TGA2 adapter this change
merely results that the memory management fault is replaced by a
machine check.
these two reasons:
1. On ia64 a function pointer does not hold the address of the first
instruction of a functions implementation. It holds the address
of a function descriptor. Hence the user(), btrap(), eintr() and
bintr() prototypes are wrong for getting the actual code address.
2. The logic forces interrupt, trap and exception entry points to
be layed-out contiguously. This can not be achieved on ia64 and is
generally just bad programming.
The MCOUNT_FROMPC_USER macro is used to set the frompc argument to
some kernel address which represents any frompc that falls outside
the kernel text range. The macro can expand to ~0U to bail out in
that case.
The MCOUNT_FROMPC_INTR macro is used to set the frompc argument to
some kernel address to represent a call to a trap or interrupt
handler. This to avoid that the trap or interrupt handler appear to
be called from everywhere in the call graph. The macro can expand
to ~0U to prevent adjusting frompc. Note that the argument is selfpc,
not frompc.
This commit defines the macros on all architectures equivalently to
the original code in sys/libkern/mcount.c. People can take it from
here...
Compile-tested on: alpha, amd64, i386, ia64 and sparc64
Boot-tested on: i386
valid pmap to the pmap functions that require one. Remove the checks for
NULL. (These checks have their origins in the Mach pmap.c that was
integrated into BSD. None of the new code written specifically for
FreeBSD included them.)
compile option. All FreeBSD packet filters now use the PFIL_HOOKS API and
thus it becomes a standard part of the network stack.
If no hooks are connected the entire packet filter hooks section and related
activities are jumped over. This removes any performance impact if no hooks
are active.
Both OpenBSD and DragonFlyBSD have integrated PFIL_HOOKS permanently as well.
directly. This removes a few more users of the stackgap and also marks
the syscalls using these wrappers MP safe where appropriate.
Tested on: i386 with linux acroread5
Compiled on: i386, alpha LINT
contained "sanity" checks that could be violated if another CPU modified
the pmap between the emulation trap and locking the pmap in
pmap_emulate_reference(). As a result, the pte could be inconsistent
with the access that caused the emulation trap. In such cases,
pmap_emulate_reference() now flushes the current CPU's TLB entry and
returns.
- Make pmap_changebit() an inline function, reducing object code size.
to allow dumping per-thread machine specific notes. On ia64 we use this
function to flush the dirty registers onto the backingstore before we
write out the PRSTATUS notes.
Tested on: alpha, amd64, i386, ia64 & sparc64
Not tested on: arm, powerpc
vm_page_sleep_if_busy() and the page table page's busy flag as a
synchronization mechanism on page table pages.
Also, relocate the inline pmap_unwire_pte_hold() so that it can be used
to shorten _pmap_unwire_pte_hold() on alpha and amd64. This places
pmap_unwire_pte_hold() next to a comment that more accurately describes
it than _pmap_unwire_pte_hold().
being defined, define and use a new MD macro, cpu_spinwait(). It only
expands to something on i386 and amd64, so the compiled code should be
identical.
Name of the macro found by: jhb
Reviewed by: jhb
their own directory and module, leaving the MD parts in the MD
area (the MD parts _are_ part of the modules). /dev/mem and /dev/io
are now loadable modules, thus taking us one step further towards
a kernel created entirely out of modules. Of course, there is nothing
preventing the kernel from having these statically compiled.
- Enable recursion on the page queues lock. This allows calls to
vm_page_alloc(VM_ALLOC_NORMAL) and UMA's obj_alloc() with the page
queues lock held. Such calls are made to allocate page table pages
and pv entries.
- The previous change enables a partial reversion of vm/vm_page.c
revision 1.216, i.e., the call to vm_page_alloc() by vm_page_cowfault()
now specifies VM_ALLOC_NORMAL rather than VM_ALLOC_INTERRUPT.
- Add partial locking to pmap_copy(). (As a side-effect, pmap_copy()
should now be faster on i386 SMP because it no longer generates IPIs
for TLB shootdown on the other processors.)
- Complete the locking of pmap_enter() and pmap_enter_quick(). (As of now,
all changes to a user-level pmap on alpha, amd64, and i386 are performed
with appropriate locking.)
dereference curthread. It is called only from critical_{enter,exit}(),
which already dereferences curthread. This doesn't seem to affect SMP
performance in my benchmarks, but improves MySQL transaction throughput
by about 1% on UP on my Xeon.
Head nodding: jhb, bmilekic
somewhat clearer, but more importantly allows for a consistent naming
scheme for suser_cred flags.
The old name is still defined, but will be removed in a few days (unless I
hear any complaints...)
Discussed with: rwatson, scottl
Requested by: jhb
the thread ID and call db_trace_thread().
Since arm has all the logic in db_stack_trace_cmd(), rename the
new DB_COMMAND function to db_stack_trace to avoid conflicts on
arm.
While here, have db_stack_trace parse its own arguments so that
we can use a more natural radix for IDs. If the ID is not a thread
ID, or more precisely when no thread exists with the ID, try if
there's a process with that ID and return the first thread in it.
This makes it easier to print stack traces from the ps output.
requested by: rwatson@
tested on: amd64, i386, ia64
allocated as "no object" pages. Similar changes were made to the amd64
and i386 pmap last year. The primary reason being that maintaining
a pte object leads to lock order violations. A secondary reason being
that the pte object is redundant, i.e., the page table itself can be
used to lookup page table pages. (Historical note: The pte object
predates our ability to allocate "no object" pages. Thus, the pte
object was a necessary evil.)
- Unconditionally check the vm object lock's status in vm_page_remove().
Previously, this assertion could not be made on Alpha due to its use
of a pte object.
a fast interrupt handler doing an swi_sched(). This fixed the lockups I
saw on my laptop when using xmms in KDE and on rwatson's MySQL benchmarks
on SMP. This will eventually be removed and/or modified when I figure out
what the root cause is and fix that.
valid.
Implement the protection check required by the pmap_extract_and_hold()
specification. (This enables the elimination of Giant from that function.)
future:
rename ttyopen() -> tty_open() and ttyclose() -> tty_close().
We need the ttyopen() and ttyclose() for the new generic cdevsw
functions for tty devices in order to have consistent naming.
pmap_protect() and pmap_remove(). In general, they require the lock in
order to modify a page's pv list or flags. In some cases, however,
pmap_protect() can avoid acquiring the lock.
for unknown events.
A number of modules return EINVAL in this instance, and I have left
those alone for now and instead taught MOD_QUIESCE to accept this
as "didn't do anything".
pmap_remove_pages(). (The implementation of pmap_remove_pages() is
optional. If pmap_remove_pages() is unimplemented, the acquisition and
release of the page queues lock is unnecessary.)
Remove spl calls from the alpha, arm, and ia64 pmap_remove_pages().
Most of the changes are a direct result of adding thread awareness.
Typically, DDB_REGS is gone. All registers are taken from the
trapframe and backtraces use the PCB based contexts. DDB_REGS was
defined to be a trapframe on all platforms anyway.
Thread awareness introduces the following new commands:
thread X switch to thread X (where X is the TID),
show threads list all threads.
The backtrace code has been made more flexible so that one can
create backtraces for any thread by giving the thread ID as an
argument to trace.
With this change, ia64 has support for breakpoints.
o Make debugging support conditional upon KDB instead of DDB.
o Call kdb_trap() according to the new world order.
o Kill the NO_SIO option completely.
o Respect the boot_gdb environment variable.
o Don't make debug specific kernel options conditional.
o Remove implementation of Debugger().
it's in the way even more. Basicly: remove all alpha specific console
support from gfb(4), sio(4) and syscons(4). Rewrite the alpha console
initialization to be identical to all other platforms. In a nutshell:
call cninit().
The platform specific code now only sets or clears RB_SERIAL and thus
automaticly causes the right console to be selected.
sio.c:
o Replace the remote GDB hacks and use the GDB debug port interface
instead.
o Make debugging code conditional upon KDB instead of DDB.
o Call kdb_alt_break() instead of db_alt_break().
o Call kdb_enter() instead of breakpoint().
o Remove the ugly compatibility of using the console as the debug
port.
a PCB from a trapframe for purposes of unwinding the stack. The PCB
is used as the thread context and all but the thread that entered the
debugger has a valid PCB.
This function can also be used to create a context for the threads
running on the CPUs that have been stopped when the debugger got
entered. This however is not done at the time of this commit.
in which multiple (presumably different) debugger backends can be
configured and which provides basic services to those backends.
Besides providing services to backends, it also serves as the single
point of contact for any and all code that wants to make use of the
debugger functions, such as entering the debugger or handling of the
alternate break sequence. For this purpose, the frontend has been
made non-optional.
All debugger requests are forwarded or handed over to the current
backend, if applicable. Selection of the current backend is done by
the debug.kdb.current sysctl. A list of configured backends can be
obtained with the debug.kdb.available sysctl. One can enter the
debugger by writing to the debug.kdb.enter sysctl.
backend improves over the old GDB support in the following ways:
o Unified implementation with minimal MD code.
o A simple interface for devices to register themselves as debug
ports, ala consoles.
o Compression by using run-length encoding.
o Implements GDB threading support.
bootp -> BOOTP
bootp.nfsroot -> BOOTP_NFSROOT
bootp.nfsv3 -> BOOTP_NFSV3
bootp.compat -> BOOTP_COMPAT
bootp.wired_to -> BOOTP_WIRED_TO
- i.e. back out the previous commit. It's already possible to
pxeboot(8) with a GENERIC kernel.
Pointed out by: dwmalone
BOOTP -> bootp
BOOTP_NFSROOT -> bootp.nfsroot
BOOTP_NFSV3 -> bootp.nfsv3
BOOTP_COMPAT -> bootp.compat
BOOTP_WIRED_TO -> bootp.wired_to
This lets you PXE boot with a GENERIC kernel by putting this sort of thing
in loader.conf:
bootp="YES"
bootp.nfsroot="YES"
bootp.nfsv3="YES"
bootp.wired_to="bge1"
or even setting the variables manually from the OK prompt.
than as one-off hacks in various other parts of the kernel:
- Add a function maybe_preempt() that is called from sched_add() to
determine if a thread about to be added to a run queue should be
preempted to directly. If it is not safe to preempt or if the new
thread does not have a high enough priority, then the function returns
false and sched_add() adds the thread to the run queue. If the thread
should be preempted to but the current thread is in a nested critical
section, then the flag TDF_OWEPREEMPT is set and the thread is added
to the run queue. Otherwise, mi_switch() is called immediately and the
thread is never added to the run queue since it is switch to directly.
When exiting an outermost critical section, if TDF_OWEPREEMPT is set,
then clear it and call mi_switch() to perform the deferred preemption.
- Remove explicit preemption from ithread_schedule() as calling
setrunqueue() now does all the correct work. This also removes the
do_switch argument from ithread_schedule().
- Do not use the manual preemption code in mtx_unlock if the architecture
supports native preemption.
- Don't call mi_switch() in a loop during shutdown to give ithreads a
chance to run if the architecture supports native preemption since
the ithreads will just preempt DELAY().
- Don't call mi_switch() from the page zeroing idle thread for
architectures that support native preemption as it is unnecessary.
- Native preemption is enabled on the same archs that supported ithread
preemption, namely alpha, i386, and amd64.
This change should largely be a NOP for the default case as committed
except that we will do fewer context switches in a few cases and will
avoid the run queues completely when preempting.
Approved by: scottl (with his re@ hat)
to <sys/gmon.h>. Cleaned them up a little by not attempting to ifdef
for incomplete and out of date support for GUPROF in userland, as in
the sparc64 version.
elf_reloc() backends for two reasons. First, to support the possibility
of there being two elf linkers in the kernel (eg: amd64), and second, to
pass the relocbase explicitly (for relocating .o format kld files).
caller to vm_page_grab(). Although this gives VM_ALLOC_ZERO a
different meaning for vm_page_grab() than for vm_page_alloc(), I feel
such change is necessary to accomplish other goals. Specifically, I
want to make the PG_ZERO flag immutable between the time it is
allocated by vm_page_alloc() and freed by vm_page_free() or
vm_page_free_zero() to avoid locking overheads. Once we gave up on
the ability to automatically recognize a zeroed page upon entry to
vm_page_free(), the ability to mutate the PG_ZERO flag became useless.
Instead, I would like to say that "Once a page becomes valid, its
PG_ZERO flag must be ignored."
move its declaration to the machine-dependent header file on those
machines that use it. In principle, only i386 should have it.
Alpha and AMD64 should use their direct virtual-to-physical mapping.
- Remove pmap_kenter_temporary() from ia64. It is unused. Approved
by: marcel@
