function on the possibility of a thread to not preempt.
As this function is very tied to x86 (interrupts disabled checkings)
it is not intended to be used in MI code.
Add pmap_invalidate_cache_pages() method on x86. It flushes the CPU
cache for the set of pages, which are not neccessary mapped. Since its
supposed use is to prepare the move of the pages ownership to a device
that does not snoop all CPU accesses to the main memory (read GPU in
GMCH), do not rely on CPU self-snoop feature.
amd64 implementation takes advantage of the direct map. On i386,
extract the helper pmap_flush_page() from pmap_page_set_memattr(), and
use it to make a temporary mapping of the flushed page.
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 3 weeks
32 bits. Some times compiler inserts unnecessary instructions to preserve
unused upper 32 bits even when it is casted to a 32-bit value. It reduces
such compiler mistakes where every cycle counts.
functions are implemented with CMPXCHG8B instruction where it is available,
i. e., all Pentium-class and later processors. Note this instruction is
also used for atomic_store_rel_64() because a simple XCHG-like instruction
for 64-bit memory access does not exist, unfortunately. If the processor
lacks the instruction, i. e., 80486-class CPUs, two 32-bit load/store are
performed with interrupt temporarily disabled, assuming it does not support
SMP. Although this assumption may be little naive, it is true in reality.
This implementation is inspired by Linux.
at run-time on i386. cpu_ticks() is set to use RDTSC early enough on i386
where it is available. Otherwise, cpu_ticks() is driven by the current
timecounter hardware as binuptime(9) does. This also avoids unnecessary
namespace pollution from <machine/cputypes.h>.
Also, express this new maximum as a fraction of the kernel's address
space size rather than a constant so that increasing KVA_PAGES will
automatically increase this maximum. As a side-effect of this change,
kern.maxvnodes will automatically increase by a proportional amount.
While I'm here ensure that this change doesn't result in an unintended
increase in maxpipekva on i386. Calculate maxpipekva based upon the
size of the kernel address space and the amount of physical memory
instead of the size of the kmem map. The memory backing pipes is not
allocated from the kmem map. It is allocated from its own submap of
the kernel map. In short, it has no real connection to the kmem map.
(In fact, the commit messages for the maxpipekva auto-sizing talk
about using the kernel map size, cf. r117325 and r117391, even though
the implementation actually used the kmem map size.) Although the
calculation is now done differently, the resulting value for
maxpipekva should remain almost the same on i386. However, on amd64,
the value will be reduced by 2/3. This is intentional. The recent
change to VM_KMEM_SIZE_SCALE on amd64 for the benefit of ZFS also had
the unnecessary side-effect of increasing maxpipekva. This change is
effectively restoring maxpipekva on amd64 to its prior value.
Eliminate init_param3() since it is no longer used.
Unfortunately, it pulls in <machine/cputypes.h> but it is small enough and
namespace pollution is minimal, I hope.
Pointed out by: bde
Pointy hat: jkim
soon as possible for stack protector. However, dummy timecounter does not
have enough entropy and we don't need to sacrifice Pentium class and later.
Pointed out by: Maxim Dounin (mdounin at mdounin dot ru)
Compile sys/dev/mem/memutil.c for all supported platforms and remove now
unnecessary dev_mem_md_init(). Consistently define mem_range_softc from
mem.c for all platforms. Add missing #include guards for machine/memdev.h
and sys/memrange.h. Clean up some nearby style(9) nits.
MFC after: 1 month
architecture macros (__mips_n64, __powerpc64__) when 64 bit types (and
corresponding macros) are different from 32 bit. [1]
Correct the type of INT64_MIN, INT64_MAX and UINT64_MAX.
Define (U)INTMAX_C as an alias for (U)INT64_C matching the type definition
for (u)intmax_t. Do this on all architectures for consistency.
Suggested by: bde [1]
Approved by: kib (mentor)
of (unsigned) int __attribute__((__mode__(__DI__))). This aligns better
with macros such as (U)INT64_C, (U)INT64_MAX, etc. which assume (u)int64_t
has type (unsigned) long long.
The mode attribute was used because long long wasn't standardised until
C99. Nowadays compilers should support long long and use of the mode
attribute is discouraged according to GCC Internals documentation.
The type definition has to be marked with __extension__ to support
compilation with "-std=c89 -pedantic".
Discussed with: bde
Approved by: kib (mentor)
On some architectures UCHAR_MAX and USHRT_MAX had type unsigned int.
However, lacking integer suffixes for types smaller than int, their type
should correspond to that of an object of type unsigned char (or short)
when used in an expression with objects of type int. In that case unsigned
char (short) are promoted to int (i.e. signed) so the type of UCHAR_MAX and
USHRT_MAX should also be int.
Where MIN/MAX constants implicitly have the correct type the suffix has
been removed.
While here, correct some comments.
Reviewed by: bde
Approved by: kib (mentor)
It was used mainly to discover and fix some 64-bit portability problems
before 64-bit arches were widely available.
Discussed with: bde
Approved by: kib (mentor)
mechanical change. This opens the door for using PV device drivers
under Xen HVM on i386, as well as more general harmonisation of i386
and amd64 Xen support in FreeBSD.
Reviewed by: cperciva
MFC after: 3 weeks
When cleaning up a thread, reset its LDT to the default LDT.
Note: Casting the LDT pointer to an int and storing it in pc_currentldt is
wildly bogus, but is harmless since pc_currentldt is a write-only variable.
MFC after: 3 days
Don't map physical to machine page numbers in pte_load_store, since it uses
PT_SET_VA (which takes a physical page number and converts it to a machine
page number).
MFC after: 3 days
the original amd64 and i386 headers with stubs.
Rename (AMD64|I386)_BUS_SPACE_* to X86_BUS_SPACE_* everywhere.
Reviewed by: imp (previous version), jhb
Approved by: kib (mentor)
Passing a count of zero on i386 and amd64 for [I386|AMD64]_BUS_SPACE_MEM
causes a crash/hang since the 'loop' instruction decrements the counter
before checking if it's zero.
PR: kern/80980
Discussed with: jhb
functions, they are unused. Remove 'user' from npxgetuserregs()
etc. names.
For {npx,fpu}{get,set}regs(), always use pcb->pcb_user_save for FPU
context storage. This eliminates the need for ugly copying with
overwrite of the newly added and reserved fields in ucontext on i386
to satisfy alignment requirements for fpusave() and fpurstor().
pc98 version was copied from i386.
Suggested and reviewed by: bde
Tested by: pho (i386 and amd64)
MFC after: 1 week
_HYPERVISOR_multicall, and create a new HYPERVISOR_multicall function which
invokes _HYPERVISOR_multicall and checks that the individual hypercalls all
succeeded.
Clean up the code by converting xpmap_ptom(VTOP(...)) to VTOM(...) and
converting xpmap_ptom(VM_PAGE_TO_PHYS(...)) to VM_PAGE_TO_MACH(...). In
a few places we take advantage of the fact that xpmap_ptom can commute with
setting PG_* flags.
This commit should have no net effect save to improve the readability of
this code.
These MSRs can be used to determine actual (average) performance as
compared to a maximum defined performance.
Availability of these MSRs is indicated by bit0 in CPUID.6.ECX on both
Intel and AMD processors.
MFC after: 5 days
It seems that this MSR has been available in a range of AMD processors
families for quite a while now.
Note1: not all AMD MSRs that are found in amd64 specialreg.h are also in
the i386 version.
Note2: perhaps some additional name component is needed to distinguish
AMD-specific MSRs.
MFC after: 5 days
contents of the ones that were not empty were stale and unused.
- Now that <machine/mutex.h> no longer exists, there is no need to allow it
to override various helper macros in <sys/mutex.h>.
- Rename various helper macros for low-level operations on mutexes to live
in the _mtx_* or __mtx_* namespaces. While here, change the names to more
closely match the real API functions they are backing.
- Drop support for including <sys/mutex.h> in assembly source files.
Suggested by: bde (1, 2)
