now it uses a very dumb first-touch allocation policy. This will change in
the future.
- Each architecture indicates the maximum number of supported memory domains
via a new VM_NDOMAIN parameter in <machine/vmparam.h>.
- Each cpu now has a PCPU_GET(domain) member to indicate the memory domain
a CPU belongs to. Domain values are dense and numbered from 0.
- When a platform supports multiple domains, the default freelist
(VM_FREELIST_DEFAULT) is split up into N freelists, one for each domain.
The MD code is required to populate an array of mem_affinity structures.
Each entry in the array defines a range of memory (start and end) and a
domain for the range. Multiple entries may be present for a single
domain. The list is terminated by an entry where all fields are zero.
This array of structures is used to split up phys_avail[] regions that
fall in VM_FREELIST_DEFAULT into per-domain freelists.
- Each memory domain has a separate lookup-array of freelists that is
used when fulfulling a physical memory allocation. Right now the
per-domain freelists are listed in a round-robin order for each domain.
In the future a table such as the ACPI SLIT table may be used to order
the per-domain lookup lists based on the penalty for each memory domain
relative to a specific domain. The lookup lists may be examined via a
new vm.phys.lookup_lists sysctl.
- The first-touch policy is implemented by using PCPU_GET(domain) to
pick a lookup list when allocating memory.
Reviewed by: alc
allow pmap_enter() to be performed on an unmanaged page that doesn't have
VPO_BUSY set. Having VPO_BUSY set really only matters for managed pages.
(See, for example, pmap_remove_write().)
PG_REFERENCED changes in vm_pageout_object_deactivate_pages().
Simplify this function's inner loop using TAILQ_FOREACH(), and shorten
some of its overly long lines. Update a stale comment.
Assert that PG_REFERENCED may be cleared only if the object containing
the page is locked. Add a comment documenting this.
Assert that a caller to vm_page_requeue() holds the page queues lock,
and assert that the page is on a page queue.
Push down the page queues lock into pmap_ts_referenced() and
pmap_page_exists_quick(). (As of now, there are no longer any pmap
functions that expect to be called with the page queues lock held.)
Neither pmap_ts_referenced() nor pmap_page_exists_quick() should ever
be passed an unmanaged page. Assert this rather than returning "0"
and "FALSE" respectively.
ARM:
Simplify pmap_page_exists_quick() by switching to TAILQ_FOREACH().
Push down the page queues lock inside of pmap_clearbit(), simplifying
pmap_clear_modify(), pmap_clear_reference(), and pmap_remove_write().
Additionally, this allows for avoiding the acquisition of the page
queues lock in some cases.
PowerPC/AIM:
moea*_page_exits_quick() and moea*_page_wired_mappings() will never be
called before pmap initialization is complete. Therefore, the check
for moea_initialized can be eliminated.
Push down the page queues lock inside of moea*_clear_bit(),
simplifying moea*_clear_modify() and moea*_clear_reference().
The last parameter to moea*_clear_bit() is never used. Eliminate it.
PowerPC/BookE:
Simplify mmu_booke_page_exists_quick()'s control flow.
Reviewed by: kib@
When I pushed down the page queues lock into pmap_is_modified(), I created
an ordering dependence: A pmap operation that clears PG_WRITEABLE and calls
vm_page_dirty() must perform the call first. Otherwise, pmap_is_modified()
could return FALSE without acquiring the page queues lock because the page
is not (currently) writeable, and the caller to pmap_is_modified() might
believe that the page's dirty field is clear because it has not seen the
effect of the vm_page_dirty() call.
When I pushed down the page queues lock into pmap_is_modified(), I
overlooked one place where this ordering dependence is violated:
pmap_enter(). In a rare situation pmap_enter() can be called to replace a
dirty mapping to one page with a mapping to another page. (I say rare
because replacements generally occur as a result of a copy-on-write fault,
and so the old page is not dirty.) This change delays clearing PG_WRITEABLE
until after vm_page_dirty() has been called.
Fixing the ordering dependency also makes it easy to introduce a small
optimization: When pmap_enter() used to replace a mapping to one page with a
mapping to another page, it freed the pv entry for the first mapping and
later called the pv entry allocator for the new mapping. Now, pmap_enter()
attempts to recycle the old pv entry, saving two calls to the pv entry
allocator.
There is no point in setting PG_WRITEABLE on unmanaged pages, so don't.
pmap_is_referenced(). Eliminate the corresponding page queues lock
acquisitions from vm_map_pmap_enter() and mincore(), respectively. In
mincore(), this allows some additional cases to complete without ever
acquiring the page queues lock.
Assert that the page is managed in pmap_is_referenced().
On powerpc/aim, push down the page queues lock acquisition from
moea*_is_modified() and moea*_is_referenced() into moea*_query_bit().
Again, this will allow some additional cases to complete without ever
acquiring the page queues lock.
Reorder a few statements in vm_page_dontneed() so that a race can't lead
to an old reference persisting. This scenario is described in detail by a
comment.
Correct a spelling error in vm_page_dontneed().
Assert that the object is locked in vm_page_clear_dirty(), and restrict the
page queues lock assertion to just those cases in which the page is
currently writeable.
Add object locking to vnode_pager_generic_putpages(). This was the one
and only place where vm_page_clear_dirty() was being called without the
object being locked.
Eliminate an unnecessary vm_page_lock() around vnode_pager_setsize()'s call
to vm_page_clear_dirty().
Change vnode_pager_generic_putpages() to the modern-style of function
definition. Also, change the name of one of the parameters to follow
virtual memory system naming conventions.
Reviewed by: kib
independent code. Move this code into mincore(), and eliminate the
page queues lock from pmap_mincore().
Push down the page queues lock into pmap_clear_modify(),
pmap_clear_reference(), and pmap_is_modified(). Assert that these
functions are never passed an unmanaged page.
Eliminate an inaccurate comment from powerpc/powerpc/mmu_if.m:
Contrary to what the comment says, pmap_mincore() is not simply an
optimization. Without a complete pmap_mincore() implementation,
mincore() cannot return either MINCORE_MODIFIED or MINCORE_REFERENCED
because only the pmap can provide this information.
Eliminate the page queues lock from vfs_setdirty_locked_object(),
vm_pageout_clean(), vm_object_page_collect_flush(), and
vm_object_page_clean(). Generally speaking, these are all accesses
to the page's dirty field, which are synchronized by the containing
vm object's lock.
Reduce the scope of the page queues lock in vm_object_madvise() and
vm_page_dontneed().
Reviewed by: kib (an earlier version)
Extend struct sysvec with three new elements:
sv_fetch_syscall_args - the method to fetch syscall arguments from
usermode into struct syscall_args. The structure is machine-depended
(this might be reconsidered after all architectures are converted).
sv_set_syscall_retval - the method to set a return value for usermode
from the syscall. It is a generalization of
cpu_set_syscall_retval(9) to allow ABIs to override the way to set a
return value.
sv_syscallnames - the table of syscall names.
Use sv_set_syscall_retval in kern_sigsuspend() instead of hardcoding
the call to cpu_set_syscall_retval().
The new functions syscallenter(9) and syscallret(9) are provided that
use sv_*syscall* pointers and contain the common repeated code from
the syscall() implementations for the architecture-specific syscall
trap handlers.
Syscallenter() fetches arguments, calls syscall implementation from
ABI sysent table, and set up return frame. The end of syscall
bookkeeping is done by syscallret().
Take advantage of single place for MI syscall handling code and
implement ptrace_lwpinfo pl_flags PL_FLAG_SCE, PL_FLAG_SCX and
PL_FLAG_EXEC. The SCE and SCX flags notify the debugger that the
thread is stopped at syscall entry or return point respectively. The
EXEC flag augments SCX and notifies debugger that the process address
space was changed by one of exec(2)-family syscalls.
The i386, amd64, sparc64, sun4v, powerpc and ia64 syscall()s are
changed to use syscallenter()/syscallret(). MIPS and arm are not
converted and use the mostly unchanged syscall() implementation.
Reviewed by: jhb, marcel, marius, nwhitehorn, stas
Tested by: marcel (ia64), marius (sparc64), nwhitehorn (powerpc),
stas (mips)
MFC after: 1 month
here, make the style of assertion used by pmap_enter() consistent
across all architectures.
On entry to pmap_remove_write(), assert that the page is neither
unmanaged nor fictitious, since we cannot remove write access to
either kind of page.
With the push down of the page queues lock, pmap_remove_write() cannot
condition its behavior on the state of the PG_WRITEABLE flag if the
page is busy. Assert that the object containing the page is locked.
This allows us to know that the page will neither become busy nor will
PG_WRITEABLE be set on it while pmap_remove_write() is running.
Correct a long-standing bug in vm_page_cowsetup(). We cannot possibly
do copy-on-write-based zero-copy transmit on unmanaged or fictitious
pages, so don't even try. Previously, the call to pmap_remove_write()
would have failed silently.
vm_page_try_to_free(). Consequently, push down the page queues lock into
pmap_enter_quick(), pmap_page_wired_mapped(), pmap_remove_all(), and
pmap_remove_write().
Push down the page queues lock into Xen's pmap_page_is_mapped(). (I
overlooked the Xen pmap in r207702.)
Switch to a per-processor counter for the total number of pages cached.
architecture from page queue lock to a hashed array of page locks
(based on a patch by Jeff Roberson), I've implemented page lock
support in the MI code and have only moved vm_page's hold_count
out from under page queue mutex to page lock. This changes
pmap_extract_and_hold on all pmaps.
Supported by: Bitgravity Inc.
Discussed with: alc, jeffr, and kib
Clearing a page table entry's accessed bit and setting the page's
PG_REFERENCED flag in pmap_protect() can't really be justified, so
don't do it. Moreover, on ia64, don't set the page's dirty field
unless pmap_protect() is removing write access.
pmap_ts_referenced() is not always appropriate for checking whether or
not pages have been referenced because it clears any reference bits
that it encounters. For example, in mincore(), clearing the reference
bits has two negative consequences. First, it throws off the activity
count calculations performed by the page daemon. Specifically, a page
on which mincore() has called pmap_ts_referenced() looks less active
to the page daemon than it should. Consequently, the page could be
deactivated prematurely by the page daemon. Arguably, this problem
could be fixed by having mincore() duplicate the activity count
calculation on the page. However, there is a second problem for which
that is not a solution. In order to clear a reference on a 4KB page,
it may be necessary to demote a 2/4MB page mapping. Thus, a mincore()
by one process can have the side effect of demoting a superpage
mapping within another process!
to the image_params struct instead of several members of that struct
individually. This makes it easier to expand its arguments in the future
without touching all platforms.
Reviewed by: jhb
COMPAT_43TTY enables the sgtty interface. Even though its exposure has
only been removed in FreeBSD 8.0, it wasn't used by anything in the base
system in FreeBSD 5.x (possibly even 4.x?). On those releases, if your
ports/packages are less than two years old, they will prefer termios
over sgtty.
of Sun Fire V1280 doesn't round up the size itself but instead lets
claiming of non page-sized amounts of memory fail.
- Change parameters and variables related to the TLB slots to unsigned
which is more appropriate.
- Search the whole OFW device tree instead of only the children of the
root nexus device for the BSP as starting with UltraSPARC IV the 'cpu'
nodes hang off of from 'cmp' (chip multi-threading processor) or 'core'
or combinations thereof. Also in large UltraSPARC III based machines
the 'cpu' nodes hang off of 'ssm' (scalable shared memory) nodes which
group snooping-coherency domains together instead of directly from the
nexus.
- Add support for UltraSPARC IV and IV+ BSPs. Due to the fact that these
are multi-core each CPU has two Fireplane config registers and thus the
module/target ID has to be determined differently so the one specific
to a certain core is used. Similarly, starting with UltraSPARC IV the
individual cores use a different property in the OFW device tree to
indicate the CPU/core ID as it no longer is in coincidence with the
shared slot/socket ID.
While at it additionally distinguish between CPUs with Fireplane and
JBus interconnects as these also use slightly different sizes for the
JBus/agent/module/target IDs.
- Check the return value of init_heap(). This requires moving it after
cons_probe() so we can panic when appropriate. This should be fine as
the PowerPC OFW loader uses that order for quite some time now.
the 'debugging' section of any HEAD kernel and enable for the mainstream
ones, excluding the embedded architectures.
It may, of course, enabled on a case-by-case basis.
Sponsored by: Sandvine Incorporated
Requested by: emaste
Discussed with: kib
- Remove the BUS_HANDLE_MIN checking in the __BUS_DEBUG_ACCESS macro;
for UPA it should have fulfilled its purpose by now and Fireplane-
and JBus-based machines are way to messy in organization to implement
something equivalent.
- Fix a bunch of style(9) bugs.
- Const'ify the bus_stream_asi and bus_type_asi arrays.
- Replace hard-coded functions names missed in bus_machdep.c with __func__.
- Break some long lines.
sys/conf/makeLINT.mk to only do certain things for certain
architectures.
Note that neither arm nor mips have the Makefile there, thus
essentially not (yet) supporting LINT. This would enable them
do add special treatment to sys/conf/makeLINT.mk as well chosing
one of the many configurations as LINT.
This is a hack of doing this and keeping it in a separate commit
will allow us to more easily identify and back it out.
Discussed on/with: arch, jhb (as part of the LINT-VIMAGE thread)
MFC after: 1 month
while in kernel mode, and later changing signal mask to block the
signal, was fixed for sigprocmask(2) and ptread_exit(3). The same race
exists for sigreturn(2), setcontext(2) and swapcontext(2) syscalls.
Use kern_sigprocmask() instead of direct manipulation of td_sigmask to
reschedule newly blocked signals, closing the race.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
the memory or D-cache, depending on the semantics of the platform.
vm_sync_icache() is basically a wrapper around pmap_sync_icache(),
that translates the vm_map_t argumument to pmap_t.
o Introduce pmap_sync_icache() to all PMAP implementation. For powerpc
it replaces the pmap_page_executable() function, added to solve
the I-cache problem in uiomove_fromphys().
o In proc_rwmem() call vm_sync_icache() when writing to a page that
has execute permissions. This assures that when breakpoints are
written, the I-cache will be coherent and the process will actually
hit the breakpoint.
o This also fixes the Book-E PMAP implementation that was missing
necessary locking while trying to deal with the I-cache coherency
in pmap_enter() (read: mmu_booke_enter_locked).
The key property of this change is that the I-cache is made coherent
*after* writes have been done. Doing it in the PMAP layer when adding
or changing a mapping means that the I-cache is made coherent *before*
any writes happen. The difference is key when the I-cache prefetches.
compiled to use the Medium/Low code model, which we currently default
to for the userland. GNU/Linux has moved their default to Medium/Middle
some time ago, which probably explains why the current GNU ld(1) uses
a base in the range between 32 and 44 bits instead.
Submitted by: kib
by looking at the bases used for non-relocatable executables by gnu ld(1),
and adjusting it slightly.
Discussed with: bz
Reviewed by: kan
Tested by: bz (i386, amd64), bsam (linux)
MFC after: some time
has proven to have a good effect when entering KDB by using a NMI,
but it completely violates all the good rules about interrupts
disabled while holding a spinlock in other occasions. This can be the
cause of deadlocks on events where a normal IPI_STOP is expected.
* Adds an new IPI called IPI_STOP_HARD on all the supported architectures.
This IPI is responsible for sending a stop message among CPUs using a
privileged channel when disponible. In other cases it just does match a
normal IPI_STOP.
Right now the IPI_STOP_HARD functionality uses a NMI on ia32 and amd64
architectures, while on the other has a normal IPI_STOP effect. It is
responsibility of maintainers to eventually implement an hard stop
when necessary and possible.
* Use the new IPI facility in order to implement a new userend SMP kernel
function called stop_cpus_hard(). That is specular to stop_cpu() but
it does use the privileged channel for the stopping facility.
* Let KDB use the newly introduced function stop_cpus_hard() and leave
stop_cpus() for all the other cases
* Disable interrupts on CPU0 when starting the process of APs suspension.
* Style cleanup and comments adding
This patch should fix the reboot/shutdown deadlocks many users are
constantly reporting on mailing lists.
Please don't forget to update your config file with the STOP_NMI
option removal
Reviewed by: jhb
Tested by: pho, bz, rink
Approved by: re (kib)
system for configuring machine-dependent memory attributes: ..."). In
r195649, the "vm_cache_mode_t/vm_memattr_t" parameter was removed from
vm_phys_alloc_contig().
Approved by: re (kensmith)
