allocating MAXCPU VHPTs up-front. This allows us to max-out MAXCPU
without memory waste -- MAXCPU is now 32 for SMP kernels.
This change also eliminates the VHPT scaling based in the total
memory in the system. It's the workload that determines the best size
of the VHPT. The workload can be affected by the amount of memory,
but not necessarily. For example, there's no performance difference
between VHPT sizes of 256KB, 512KB and 1MB when building the LINT
kernel. This was observed with a system that has 8GB of memory.
By default the kernel will allocate a 1MB VHPT. The user can tune the
system with the "machdep.vhpt.log2size" tunable.
the kernel stack at all. The new USB stack simply caused a change
in timing that triggered a firmware bug more often. The addition
of PRINTF_BUFR_SIZE apparently triggered the same firmware bug
even more reliably.
But even with KSTACK_PAGES=5, one instance of the firmware bug
remained: booting with a CD inserted. This problem was run into
by accident after installing Debian and having to boot FreeBSD
to fixup the GPT partitioning (Thanks... not). After bumping
KSTACK_PAGES to 5, it was pretty unbelievable that the stack was
still being too small.
After updating the firmware we could boot with a CD inserted and
KSTACK_PAGES could be lowered back to 4 pages without problems.
Note: It is believed to be a timing related firmware bug, because
the machine check information showed access to the serial console
on one CPU and access to the EHCI HCD on the other CPU. Since
both are devices on the management unit and thus virtualized in
some way, any execution trace that does not include concurrent
access to the BMC from both CPUs is fine.
Note also that it's not understood exactly how increasing the
kernel stack avoided hitting the firmware bug. A change in page
faults does change timing, but it's not known if that's what's
happening here.
In any case: the problem is being monitored. Reverting back to
4 pages for the kernel stack is preferred, because it makes it
easier to switch to 16K pages (double the page size) without
wasting too much memory by not being able to half the number of
pages...
more stack hungry as compared to the old one that my RX2660 gets
a machine check and spontaneously reboots at the time the USB DVD
drive is found and attached to CAM as a mass storage device. This
doesn't happen always, but definitely varies per kernel build.
Likewise when using a 128-byte printf buffer. The additional 128
bytes that printf needs seems to be enough to have the memory stack
and register stack collide and causing a machine check.
Thus: Bump KSTACK_PAGES from 4 to 5.
o add to platforms where it was missing (arm, i386, powerpc, sparc64, sun4v)
o define as "1" on amd64 and i386 where there is no restriction
o make the type returned consistent with ALIGN
o remove _ALIGNED_POINTER
o make associated comments consistent
Reviewed by: bde, imp, marcel
Approved by: re (kensmith)
a fair number of static data structures, making this an unlikely
option to try to change without also changing source code. [1]
Change default cache line size on ia64, sparc64, and sun4v to 128
bytes, as this was what rtld-elf was already using on those
platforms. [2]
Suggested by: bde [1], jhb [2]
MFC after: 2 weeks
CACHE_LINE_SIZE constant. These constants are intended to
over-estimate the cache line size, and be used at compile-time
when a run-time tuning alternative isn't appropriate or
available.
Defaults for all architectures are 64 bytes, except powerpc
where it is 128 bytes (used on G5 systems).
MFC after: 2 weeks
Discussed on: arch@
param.h. Per request, I've placed these just after the
_NO_NAMESPACE_POLLUTION ifndef. I've not renamed anything yet, but
may since we don't need the __.
Submitted by: bde, jhb, scottl, many others.
MACHINE_ARCH and MACHINE). Their purpose was to be able to test
in cpp(1), but cpp(1) only understands integer type expressions.
Using such unsupported expressions introduced a number of subtle
bugs, which were discovered by compiling with -Wundef.
allocating a VHPT per CPU. Since we don't yet know how many CPUs
are actually in the system at the time we need to allocate the
VHPTs, we allocate for MAXCPU processors. This can result in a
lot of wasted space for 2-way machines. So, for now, limit MAXCPU
to something smaller until we have something more dynamic.
to the machine-independent parts of the VM. At the same time, this
introduces vm object locking for the non-i386 platforms.
Two details:
1. KSTACK_GUARD has been removed in favor of KSTACK_GUARD_PAGES. The
different machine-dependent implementations used various combinations
of KSTACK_GUARD and KSTACK_GUARD_PAGES. To disable guard page, set
KSTACK_GUARD_PAGES to 0.
2. Remove the (unnecessary) clearing of PG_ZERO in vm_thread_new. In
5.x, (but not 4.x,) PG_ZERO can only be set if VM_ALLOC_ZERO is passed
to vm_page_alloc() or vm_page_grab().
under way to move the remnants of the a.out toolchain to ports. As the
comment in src/Makefile said, this stuff is deprecated and one should not
expect this to remain beyond 4.0-REL. It has already lasted WAY beyond
that.
Notable exceptions:
gcc - I have not touched the a.out generation stuff there.
ldd/ldconfig - still have some code to interface with a.out rtld.
old as/ld/etc - I have not removed these yet, pending their move to ports.
some includes - necessary for ldd/ldconfig for now.
Tested on: i386 (extensively), alpha
- Don't include ia64_cpu.h and cpu.h
- Guard definitions by _NO_NAMESPACE_POLLUTION
- Move definition of KERNBASE to vmparam.h
o Move definitions of IA64_RR_{BASE|MASK} to vmparam.h
o Move definitions of IA64_PHYS_TO_RR{6|7} to vmparam.h
o While here, remove some left-over Alpha references.
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
write caching is disabled on both SCSI and IDE disks where large
memory dumps could take up to an hour to complete.
Taking an i386 scsi based system with 512MB of ram and timing (in
seconds) how long it took to complete a dump, the following results
were obtained:
Before: After:
WCE TIME WCE TIME
------------------ ------------------
1 141.820972 1 15.600111
0 797.265072 0 65.480465
Obtained from: Yahoo!
Reviewed by: peter
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.
