- The new allocator won't return coherent memory for any size > PAGE_SIZE,
so don't assume we have coherent memory, and explicitely use
bus_dmamap_sync().
Freescale SoCs including the i.MX series. This also works for the newer
SoCs with the ENET gigabit controller, but doesn't use any of the new
hardware features other than enabling gigabit speed.
the right register for power managment. It
was incorrectly using the clock register
which also caused the status to be the
opposite of what it is supposed to be.
1 - its disabled
0 - its enabled
Per kirkwood spec FSS_88F6180_9x_6281_OpenSource.pdf
correctly by doing nothing, then add a panic for the default case, because
that implies that some driver asked for a sync (probably incorrectly) and
nothing was done.
there as "kern.ipc.sendfile.readahead".
- Push all nsfbuf related tunables into MD code. Don't move them
to new namespace in favor of POLA.
Reviewed by: scottl
Approved by: re (gjb)
Previous change applied in r255613 fixed build for ARMv6 but
broke it for previous architecture revisions. This commit
eventually fixes GCC build for all ARM revisions.
Approved by: cognet (mentor)
Approved by: re (kib)
pmap_clear_reference() has had exactly one caller in the kernel for
several years, more precisely, since FreeBSD 8. Now, that call no
longer exists.
Approved by: re (kib)
Sponsored by: EMC / Isilon Storage Division
While here, correct all consumers to pass NULL instead of 0 as we pass
capability rights as pointers now, not uint64_t.
Reported by: Daniel Peyrolon
Tested by: Daniel Peyrolon
Approved by: re (marius)
Apply the given advice to the specified range of addresses within the
given pmap. Depending on the advice, clear the referenced and/or
modified flags in each mapping. Superpage within the given range will
be demoted or destroyed.
Reviewed by: alc
Approved by: cognet (mentor)
Approved by: re
When clearing the modification status of the superpage, one of the
base pages produced during demotion should be marked as write disabled.
The intention is that subsequent write access may repromote.
In the current implementation this was done wrong as write permission was
granted instead of forbidden.
Approved by: cognet (mentor)
Approved by: re
for ARM.
This is quite ugly, because it has to work around a clang bug that does not
allow built-in functions to be defined, even when they're ones that are
expected to be built as part of a library.
Reviewed by: ed
MADV_DONTNEED) and madvise(..., MADV_FREE). Specifically, introduce a new
pmap function, pmap_advise(), that operates on a range of virtual addresses
within the specified pmap, allowing for a more efficient implementation of
MADV_DONTNEED and MADV_FREE. Previously, the implementation of
MADV_DONTNEED and MADV_FREE relied on per-page pmap operations, such as
pmap_clear_reference(). Intuitively, the problem with this implementation
is that the pmap-level locks are acquired and released and the page table
traversed repeatedly, once for each resident page in the range
that was specified to madvise(2). A more subtle flaw with the previous
implementation is that pmap_clear_reference() would clear the reference bit
on all mappings to the specified page, not just the mapping in the range
specified to madvise(2).
Since our malloc(3) makes heavy use of madvise(2), this change can have a
measureable impact. For example, the system time for completing a parallel
"buildworld" on a 6-core amd64 machine was reduced by about 1.5% to 2.0%.
Note: This change only contains pmap_advise() implementations for a subset
of our supported architectures. I will commit implementations for the
remaining architectures after further testing. For now, a stub function is
sufficient because of the advisory nature of pmap_advise().
Discussed with: jeff, jhb, kib
Tested by: pho (i386), marcel (ia64)
Sponsored by: EMC / Isilon Storage Division
Promoting base pages to superpages can increase TLB coverage and allow for
efficient use of page table entries. This development provides FreeBSD/ARM
with superpages management mechanism roughly equivalent to what we have for
i386 and amd64 architectures.
1. Add mechanism for automatic promotion of 4KB page mappings to 1MB section
mappings (and demotion when not needed, respectively).
2. Managed and non-kernel mappings are now superpages-aware.
3. The functionality can be enabled by setting "vm.pmap.sp_enabled" tunable to
a non-zero value (either in loader.conf or by modifying "sp_enabled"
variable in pmap-v6.c file). By default, automatic promotion is currently
disabled.
Submitted by: Zbigniew Bodek <zbb@semihalf.com>
Reviewed by: alc
Sponsored by: The FreeBSD Foundation, Semihalf
This allows for enabling and configuring superpages reservation mechanism in
order to allocate and populate 256 4KB base pages (for the purpose of
promotion to a 1MB superpage).
Submitted by: Zbigniew Bodek <zbb@semihalf.com>
Reviewed by: alc
Sponsored by: The FreeBSD Foundation, Semihalf
