- device_print_child() either lets the BUS_PRINT_CHILD
method produce the entire device announcement message or
it prints "foo0: not found\n"
Alter sys/kern/subr_bus.c:bus_generic_print_child() to take on
the previous behavior of device_print_child() (printing the
"foo0: <FooDevice 1.1>" bit of the announce message.)
Provide bus_print_child_header() and bus_print_child_footer()
to actually print the output for bus_generic_print_child().
These functions should be used whenever possible (unless you can
just use bus_generic_print_child())
The BUS_PRINT_CHILD method now returns int instead of void.
Modify everything else that defines or uses a BUS_PRINT_CHILD
method to comply with the above changes.
- Devices are 'on' a bus, not 'at' it.
- If a custom BUS_PRINT_CHILD method does the same thing
as bus_generic_print_child(), use bus_generic_print_child()
- Use device_get_nameunit() instead of both
device_get_name() and device_get_unit()
- All BUS_PRINT_CHILD methods return the number of
characters output.
Reviewed by: dfr, peter
result of a joined effort with parts contributed by Doug Rabson, Warner
Losh and Stefan Esser (hope I did not forget anybody). Part of the sources
is obtained from NetBSD with modifications.
This code is work in progress:
As of the time of the initial import, a loader.exe executable is built,
which can be loaded on an Alpha with NT only firmware, but no attempt is
made to switch to OSF PAL code as required to start an actual kernel.
active or not. The only sane thing we can do here is assume that if
APM is supported it might be active at some point, and bail.
In reality, even this isn't good enough; regardless of whether we support
APM or not, the system may well futz with the CPU's clock speed and throw
the TSC off. We need to stop using it for timekeeping except under
controlled circumstances. Curse the lack of a dependable high-resolution
timer.
equivalent to SYS_RES_MEMORY for x86 but for alpha, the rman_get_virtual()
address of the resource is initialised to point into either dense-mapped
or bwx-mapped space respectively, allowing direct memory pointers to be
used to device memory.
Reviewed by: Andrew Gallatin <gallatin@cs.duke.edu>
This function is called for each device for which no driver
was found.
Output is similar to the eisa_probe_nomatch() function but with the
added benefit of displaying the assigned IRQ (since PCI gives us
this information up front.)
Output is like so:
pci0: unknown card CPQ0508 (vendor=0x0e11, dev=0x0508) at 11.0 irq 9
pci0: unknown card DFZ0508 (vendor=0x10da, dev=0x0508) at 11.0 irq 9
pci0: unknown card DBL0508 (vendor=0x104c, dev=0x0508) at 11.0 irq 9
pci0: unknown card DDM0011 (vendor=0x108d, dev=0x0011) at 11.0 irq 9
I'm not happy with the 3 lines of macro cruft that got added but
I consider it a temporary annoyance as those bits will be moved to
some place where PCI, EISA and ISAPNP code will be able to use them.
(Not surprisingly, this message is longer than the code in question.)
Reviewed by: peter, dfr
a PCI memory mapped region, rman_get_bushandle() returns what happens
to be a kernel virtual address pointing to the base of the PCI shared
memory window. However this is not the behavior on all platforms:
the only thing you should do with the bushandle is pass it to the
bus_spare_read()/bus_space_write() routines. If you actually do want
the kernel virtual address of the base of the PCI memory window, you
need to use rman_get_virtual().
The problem is that at the moment, rman_get_virtual() returns a physical
address, which is bad. In order to get the kernel virtual address we
need, we have to play with it a little.
Presumeably this behavior will be changed, but in the meantime the
Tigon driver won't work. So for the moment, I'm adding a kludge to
make things happy on the alpha: the correct kernel virtual address
is calculated from the value returned by rman_get_virtual(). This
should be removed once rman_get_virtual() starts doing the right
thing.
This should make the Tigon actuall work on the alpha now.
macros) to the signal handler, for old-style BSD signal handlers as
the second (int) argument, for SA_SIGINFO signal handlers as
siginfo_t->si_code. This is source-compatible with Solaris, except
that we have no <siginfo.h> (which isn't even mentioned in POSIX
1003.1b).
An rather complete example program is at
http://www3.cons.org/cracauer/freebsd-signal.c
This will be added to the regression tests in src/.
This commit also adds code to disable the (hardware) FPU from
userconfig, so that you can use a software FP emulator on a machine
that has hardware floating point. See LINT.
ethernet controllers based on the AIC-6915 "Starfire" controller chip.
There are single port, dual port and quad port cards, plus one 100baseFX
card. All are 64-bit PCI devices, except one single port model.
The Starfire would be a very nice chip were it not for the fact that
receive buffers have to be longword aligned. This requires buffer
copying in order to achieve proper payload alignment on the alpha.
Payload alignment is enforced on both the alpha and x86 platforms.
The Starfire has several different DMA descriptor formats and transfer
mechanisms. This driver uses frame descriptors for transmission which
can address up to 14 packet fragments, and a single fragment descriptor
for receive. It also uses the producer/consumer model and completion
queues for both transmit and receive. The transmit ring has 128
descriptors and the receive ring has 256.
This driver supports both FreeBSD/i386 and FreeBSD/alpha, and uses newbus
so that it can be compiled as a loadable kernel module. Support for BPF
and hardware multicast filtering is included.
Translated from: a similar fix in ufs_readwrite.c rev.1.61.
Don't forget to set DE_ACCESS for short reads.
Check for invalid (negative) offsets before checking for reads of
0 bytes, as in ufs, although checking for invalid offsets at all
is probably a bug.
Set IN_ACCESS for successful reads of 0 bytes (except for requests to
read 0 bytes). This was broken in rev.1.42.
PR: misc/10148
Don't set IN_ACCESS for requests to read 0 bytes.
Don't set IN_ACCESS for unsuccessful reads.
Change "void *" to "volatile TYPE *", improving type safety
and eliminating some warnings (e.g., mp_machdep.c rev 1.106).
cpufunc.h:
Eliminate setbits. As defined, it's not precisely correct;
and it's redundant. (Use atomic_set_int instead.)
ipl_funcs.c:
Use atomic_set_int instead of setbits.
systm.h:
Include atomic.h.
Reviewed by: bde
the loop and not set an error, so we would then try to access an invalid
mbuf...
PR: 12780
Submitted by: bright@rush.net aka zb^3
a new record in length a pr was open... only about a half hour...
critical mbuf fields to sane values. Simplify the use of ETHER_ALIGN to
enforce payload alignment, and turn it on on the x86 as well as alpha
since it helps with NFS which wants the payload to be longword aligned
even though the hardware doesn't require it.
This fixes a problem with the ti driver causing an unaligned access trap
on the Alpha due to m_adj() sometimes not setting the alignment correctly
because of incomplete mbuf initialization.
the driver_t declaration should be "skc" not "sk". Technically, "skc"
is the parent PCI device (the SysKonnect GEnesis controller) and "sk0"
and "sk1" are the network interfaces that get attached to it.
been booted works too -- very neat. However I don't want the system to
stop for 5 seconds when the MII autoprobe is triggered in the xl and
tl drivers since that's lame. Instead, only use the hard delay when
we've been cold booted. If not, use the timeout mechanism instead.
(The SysKonnect driver doesn't use the same autonegotiation scheme, so
no change is required there.)
the device numbers are now minor number only, so that we can still
compare them after dev_t has turned into a blob.
Broken-by: dev_t changes
Reported-by: Vallo Kallaste <vallo@matti.ee>
"Niels Chr. Bank-Pedersen" <ncbp@bank-pedersen.dk>
When creating new processes (or performing exec), the new page
directory is initialized too early. The kernel might grow before
p_vmspace is initialized for the new process. Since pmap_growkernel
doesn't yet know about the new page directory, it isn't updated, and
subsequent use causes a failure.
The fix is (1) to clear p_vmspace early, to stop pmap_growkernel
from stomping on memory, and (2) to defer part of the initialization
of new page directories until p_vmspace is initialized.
PR: kern/12378
Submitted by: tegge
Reviewed by: dfr
- In isa_dmastart() and isa_dmadone(), cache flush.
- Correct current word register address.
Submitted by (partial): Toshikazu Kaho <kaho@elam.kais.kyoto-u.ac.jp>
by removing a floppy that as being operated on.
The spagghetti is hardly understandable at all anymore, so i can't
100 % ascertain this is really the Right Thing to do, maybe our new
floppy driver maintainer, Jesus Monroy Jr can do this. :-))
numbers that we have been doing in the past, and read /etc/fstab off the
proposed root filesystem to determine the actual device name and vfs
type for the root filesystem. These are then exported to the kernel
via the environment variable vfs.root.mountfrom.
Also includes a workaround fro an apparent chip bug
where UDMA mode 2 can overpower the UDMA engine enough that it will
hog the PCI bus to the exclusion of the processor.
into a loadable module, and all of the platform dependencies are gone
(except for the alpha_XXX_dmamap() thing, which is another issue -- I
still don't know how to use the busdma stuff with a network driver).
Also increase the delay in xl_reset(); testing on a 486/66 with a 3c905C
shows that reading the EEPROM fails immediately after a reset. Waiting
a little longer after the reset completes seems to fix it.
also gets the device by st_rdev, which is alright except for the fact that
the sysctl kern.dumpdev passed out a char device. This is a workaround.
Sorry for not committing the fix earlier, before people started having
problems.
The structure is the right length, but some of the members (notably
wi_q_info) were off a bit. This causes the received signal strength
values to appear bogus.
vnodes referencing this device.
Details:
cdevsw->d_parms has been removed, the specinfo is available
now (== dev_t) and the driver should modify it directly
when applicable, and the only driver doing so, does so:
vn.c. I am not sure the logic in checking for "<" was right
before, and it looks even less so now.
An intial pool of 50 struct specinfo are depleted during
early boot, after that malloc had better work. It is
likely that fewer than 50 would do.
Hashing is done from udev_t to dev_t with a prime number
remainder hash, experiments show no better hash available
for decent cost (MD5 is only marginally better) The prime
number used should not be close to a power of two, we use
83 for now.
Add new checkalias2() to get around the loss of info from
dev2udev() in bdevvp();
The aliased vnodes are hung on a list straight of the dev_t,
and speclisth[SPECSZ] is unused. The sharing of struct
specinfo means that the v_specnext moves into the vnode
which grows by 4 bytes.
Don't use a VBLK dev_t which doesn't make sense in MFS, now
we hang a dummy cdevsw on B/Cmaj 253 so that things look sane.
Storage overhead from all of this is O(50k).
Bump __FreeBSD_version to 400009
The next step will add the stuff needed so device-drivers can start to
hang things from struct specinfo
- Support for setting memory range attributes on SMP systems using the
new SMP rendezvous function
- Don't print the confusing default memory type message.
- Allow legal overlapping range types.
- Turn interrupts back on after setting MTRRs in UP mode (whoops)
- Don't waste time calling invltlb() after wbinvd(); it's not
SMP-compatible (interrupts are off) and unncessary because
wbinvd already flushes the TLB.
This code is now essentially feature-complete.
the caller to specify a function to be guarded between an entry and exit
barrier, as well as pre- and post-barrier functions.
The primary use for this function is synchronised update of per-cpu private
data. The implementation is almost (but not quite) MI; with a better
mechanism for masking per-CPU interrupts it could probably be hoisted.
Reviewed by: peter (partially)
Only know casualy of this is swapinfo/pstat which should be fixes
the right way: Store the actual pathname in the kernel like mount
does. [Volounteers sought for this task]
The road map from here is roughly: expand struct specinfo into struct
based dev_t. Add dev_t registration facilities for device drivers and
start to use them.
but broken, since tsc_timecounter is not initialised in that case,
and updating an uninitialised timecounter is fatal.
Fixed style bugs in the machdep.i8254_freq and machdep.tsc_freq
sysctls.
Reviewed by: phk
used for timecounting. The possible values are the names of the
physically present harware timecounters ("i8254" and "TSC" on i386's).
Fixed some nearby bitrot in comments in <sys/time.h>.
Reviewed by: phk
interrupts that were scheduled. Testing shows it didn't really do very much
and it makes the code a little more complicated (which is never a good thing).
Also fix the rambuffer offset initialization for the 512K/64K SRAM case
(512K total using 64K chips). It should be 0. The only case with a
non-standard rambuffer offset address is 1024K/64K according to the
SysKonnect manual. (My card has the 1024/64 configuration and I don't know
which card uses the 512/64 configuration, if any, so I'm not sure that
this was really a problem for anyone.)
/sys/ddb/db_input.c rev 1.19 to recognize syscons's cursor keycodes.
It is unnecessary now that scgetc() in syscons returns the escape
sequence for the cursor keys rather than their raw, internal key
codes.
been set for a mount point. Insert missing checks to ensure that all
write operations are done asynchronously when the MNT_ASYNC option
has been requested.
Submitted by: Craig A Soules <soules+@andrew.cmu.edu>
Reviewed by: Kirk McKusick <mckusick@mckusick.com>
with respect to interrupts on UP systems. (The upgrade from gcc 2.7.x
to egcs 1.1.2 produced at least one non-atomic code sequence in
swap_pager_getpages.)
In addition, the primitives are now SMP-safe, but only on SMPs. (For
portability between SMPs and UPs, modules are compiled with the SMP-safe
versions.)
Submitted by: dillon and myself
Reviewed by: bde
would make a difference. However, my previous diff _did_ change the
behavior in some way (not necessarily break it), so I'm fixing it.
Found by: bde
Submitted by: bde
Change number of VBI lines from 16 to 12 for NTSC formats.
Juha.Nurmela@quicknet.inet.fi found/fixed bug in VBI_SLEEP.
New features
MSP3430G DBX initialisation from Matt Brown <matt@dqc.org>
STB Bt878 card identification.
Hauppauge Model Number identification.
Changes to probeCard() for better eeprom identification.
Experimental TDA9850 initialisation code, from Linux bttv.
Cross Platform Changes
The driver has been reorgainsed based ideas from Brad Parker's port to Linux
to seperate OS Dependant and Independant sections.
I have backends for FreeBSD 2.2.x/3.x and 4.x newbus, BSDI, OpenBSD and NetBSD.
This commit has FreeBSD 2.2.8/2.2-stable/3.x and FreeBSD 4.x newbus backends.
Some code submitted by: Juha.Nurmela@quicknet.inet.fi
Matt Brown <matt@dqc.org>
Brad Parker <brad@parker.boston.ma.us>
Some code obtained from: Linux bttv driver
vm_map.c:
Don't set OBJ_ONEMAPPING on arbitrary vm objects. Only default
and swap type vm objects should have it set. vm_object_deallocate
already handles these cases.
vm_object.c:
If OBJ_ONEMAPPING isn't already clear in vm_object_shadow,
we are in trouble. Instead of clearing it, make it
an assertion that it is already clear.
1. Printing large quads in small bases overflowed the buffer if
sizeof(u_quad_t) > sizeof(u_long).
2. The sharpflag checks had operator precedence bugs due to excessive
parentheses in all the wrong places.
3. The explicit 0L was bogus in the quad_t comparison and useless in
the long comparision.
4. There was some more bitrot in the comment about ksprintn(). Our
ksprintn() handles bases up to 36 as well as down to 2.
Bruce has other complaints about using %q in kernel and would rather
we went towards using the C9X style %ll and/or %j. (I agree for that
matter, as long as gcc/egcs know how to deal with that.)
Submitted by: bde
not masked during handling of shared PCI interrupts. This resulted in
ASTs sometimes being discarded and softclock interrupts sometimes being
handled prematurely (sometimes = quite often on systems with shared PCI
interrupts, never on other systems).
Debugged by: gibbs and other people at plutotech.com
PR: 6944, maybe 12381
I don't know if it was intentional or not, but it would have printed out:
/compat/linux/foo/bar.so: interpreter not found
If it was, then I've broken it. De-constifying the 'interp' variable
or carrying the constness through to elf_load_file() are alternatives.
Alpha believes that %q is for long long, whereas our quad_t and int64_t
is only just a plain long. long long on the alpha is the same size (64
bit) as a long. It was requested, but I have not implemented yet, support
for C9X style %lld - it should be pretty easy though.
gigabit ethernet adapters. This includes two single port cards
(single mode and multimode fiber) and two dual port cards (also single
mode and multimode fiber). SysKonnect is currently the only
vendor with a dual port gigabit ethernet NIC.
The ports on dual port adapters are treated as separate network
interfaces. Thus, if you have an SK-9844 dual port SX card, you
should have both sk0 and sk1 interfaces attached. Dual port cards
are implemented using two XMAC II chips connected to a single
SysKonnect GEnesis controller. Hence, dual port cards are really
one PCI device, as opposed to two separate PCI devices connected
through a PCI to PCI bridge. Note that SysKonnect's drivers use
the two ports for failover purposes rather that as two separate
interfaces, plus they don't support jumbo frames. This applies to
their Linux driver too. :)
Support is provided for hardware multicast filtering, BPF and
jumbo frames. The SysKonnect cards support TCP checksum offload
however this feature is not currently enabled (hopefully it will
be once we get checksum offload support).
There are still a few things that need to be implemeted, like
the ability to communicate with the on-board LM80 voltage/temperature
monitor, but I wanted to get the driver under CVS control and into
-current so people could bang on it.
A big thanks for SysKonnect for making all their programming info
for these cards (and for their FDDI and token ring cards) available
without NDA (see www.syskonnect.com).
large (1G) memory machine configurations. I was able to run 'dbench 32'
on a 32MB system without bring the machine to a grinding halt.
* buffer cache hash table now dynamically allocated. This will
have no effect on memory consumption for smaller systems and
will help scale the buffer cache for larger systems.
* minor enhancement to pmap_clearbit(). I noticed that
all the calls to it used constant arguments. Making
it an inline allows the constants to propogate to
deeper inlines and should produce better code.
* removal of inherent vfs_ioopt support through the emplacement
of appropriate #ifdef's, with John's permission. If we do not
find a use for it by the end of the year we will remove it entirely.
* removal of getnewbufloops* counters & sysctl's - no longer
necessary for debugging, getnewbuf() is now optimal.
* buffer hash table functions removed from sys/buf.h and localized
to vfs_bio.c
* VFS_BIO_NEED_DIRTYFLUSH flag and support code added
( bwillwrite() ), allowing processes to block when too many dirty
buffers are present in the system.
* removal of a softdep test in bdwrite() that is no longer necessary
now that bdwrite() no longer attempts to flush dirty buffers.
* slight optimization added to bqrelse() - there is no reason
to test for available buffer space on B_DELWRI buffers.
* addition of reverse-scanning code to vfs_bio_awrite().
vfs_bio_awrite() will attempt to locate clusterable areas
in both the forward and reverse direction relative to the
offset of the buffer passed to it. This will probably not
make much of a difference now, but I believe we will start
to rely on it heavily in the future if we decide to shift
some of the burden of the clustering closer to the actual
I/O initiation.
* Removal of the newbufcnt and lastnewbuf counters that Kirk
added. They do not fix any race conditions that haven't already
been fixed by the gbincore() test done after the only call
to getnewbuf(). getnewbuf() is a static, so there is no chance
of it being misused by other modules. ( Unless Kirk can think
of a specific thing that this code fixes. I went through it
very carefully and didn't see anything ).
* removal of VOP_ISLOCKED() check in flushbufqueues(). I do not
think this check is necessary, the buffer should flush properly
whether the vnode is locked or not. ( yes? ).
* removal of extra arguments passed to getnewbuf() that are not
necessary.
* missed cluster_wbuild() that had to be a cluster_wbuild_wb() in
vfs_cluster.c
* vn_write() now calls bwillwrite() *PRIOR* to locking the vnode,
which should greatly aid flushing operations in heavy load
situations - both the pageout and update daemons will be able
to operate more efficiently.
* removal of b_usecount. We may add it back in later but for now
it is useless. Prior implementations of the buffer cache never
had enough buffers for it to be useful, and current implementations
which make more buffers available might not benefit relative to
the amount of sophistication required to implement a b_usecount.
Straight LRU should work just as well, especially when most things
are VMIO backed. I expect that (even though John will not like
this assumption) directories will become VMIO backed some point soon.
Submitted by: Matthew Dillon <dillon@backplane.com>
Reviewed by: Kirk McKusick <mckusick@mckusick.com>
clears out the transmit queue and zeroes the downlist pointer register,
but xl_txeof() isn't called before xl_start() tries to queue more packets,
xl_start() will think that the DMA is still in progress and not update
the downlist register again, thus causing packets to sit in the transmit
queue forever.
Patch provided by: Russell T Hunt <alaric@MIT.EDU>
- Correctly observe the variable `extra_history_size' when changing
the size of history (scroll back) buffer.
- Added sc_free_history_buffer().
Pointed out by: des
bit preliminary. It still returns an old-style code arg if SA_SIGINFO
is not set, but I'm not sure of the value of this since the traditional
bsd-style fourth argument (address) is missing.
Also, tidy up a bit of lint.
than a review, this was a nice puzzle.
This is supposed to be binary and source compatible with older
applications that access the old FreeBSD-style three arguments to a
signal handler.
Except those applications that access hidden signal handler arguments
bejond the documented third one. If you have applications that do,
please let me know so that we take the opportunity to provide the
functionality they need in a documented manner.
Also except application that use 'struct sigframe' directly. You need
to recompile gdb and doscmd. `make world` is recommended.
Example program that demonstrates how SA_SIGINFO and old-style FreeBSD
handlers (with their three args) may be used in the same process is at
http://www3.cons.org/tmp/fbsd-siginfo.c
Programs that use the old FreeBSD-style three arguments are easy to
change to SA_SIGINFO (although they don't need to, since the old style
will still work):
Old args to signal handler:
void handler_sn(int sig, int code, struct sigcontext *scp)
New args:
void handler_si(int sig, siginfo_t *si, void *third)
where:
old:code == new:second->si_code
old:scp == &(new:si->si_scp) /* Passed by value! */
The latter is also pointed to by new:third, but accessing via
si->si_scp is preferred because it is type-save.
FreeBSD implementation notes:
- This is just the framework to make the interface POSIX compatible.
For now, no additional functionality is provided. This is supposed
to happen now, starting with floating point values.
- We don't use 'sigcontext_t.si_value' for now (POSIX meant it for
realtime-related values).
- Documentation will be updated when new functionality is added and
the exact arguments passed are determined. The comments in
sys/signal.h are meant to be useful.
Reviewed by: BDE
in ti_rxeof() instead. This doesn't really seem to provide much in the
way of a performance boost, and I'm pretty sure it can cause mbuf leakage
in some extreme cases.
dynamicly linked binaries to run in a chroot'd environment with "emul_path"
as the new root. The new behavior of loading interpreters is identical to the
principle of overlaying.
PR: 10145
into uipc_mbuf.c. This reduces three sets of identical tunable code to
one set, and puts the initialisation with the mbuf code proper.
Make NMBUFs tunable as well.
Move the nmbclusters sysctl here as well.
Move the initialisation of maxsockets from param.c to uipc_socket2.c,
next to its corresponding sysctl.
Use the new tunable macros for the kern.vm.kmem.size tunable (this should have
been in a separate commit, whoops).
print_AMD_info(), L2 internal cache is shown, as are AMD's special CPUID
infos:
CPU: AMD-K6(tm) 3D processor (350.81-MHz 586-class CPU)
Origin = "AuthenticAMD" Id = 0x58c Stepping=12
Features=0x8021bf<FPU,VME,DE,PSE,TSC,MSR,MCE,CX8,PGE,MMX>
AMD Features=0x808029bf<FPU,VME,DE,PSE,TSC,MSR,MCE,CX8,SYSCALL,PGE,MMX,3DNow!>
PR: kern/12512
Submitted by: Louis A. Mamakos <louie@TransSys.COM>
returns 0 after ptrace() attach and/or detach doesn't quite quite
deliver a signal. Perhaps the process shouldn't be woken in this
case, but avoiding the problem is easy.
PR: 12247
Fixed a couple of places where mechanical fixing of compiler warnings
caused misspelling of NOLOCKF as NULL.
frames (or just insane received packet lengths generated due to errors
reading from the NIC's internal buffers). Anything too large to fit
safely into an mbuf cluster buffer is discarded and an error logged.
I have not observed this problem with my own cards, but on user has
reported it and adding the sanity test seems reasonable in any case.
Problem noted and patch provided by: Per Andersson <per@cdg.chalmers.se>
of the additional checks in rev.1.12 was wrong. The others are a
bit inconsistent and are probably unnecessarily pessimal. Checking
for overflow of addition, if necessary at all, should be done in
bpf_validate().
PR: 12484
we will never use more memory than this value (if specified), but will always
check memory for validity up to this amount.
Get rid of the speculative_mprobe option; the memory amount can now be
specified by hw.physmem.
allow changes to the filesystem's write_behind behavior. By the
default the filesystem aggressively issues write_behind's. Three values
may be specified for vfs.write_behind. 0 disables write_behind, 1 results
in historical operation (agressive write_behind), and 2 is an experimental
backed-off write_behind. The values of 0 and 1 are recommended. The value
of 0 is recommended in conjuction with an increase in the number of
NBUF's and the number of dirty buffers allowed (vfs.{lo,hi}dirtybuffers).
Note that a value of 0 will radically increase the dirty buffer load on
the system. Future work on write_behind behavior will use values 2 and
greater for testing purposes.
Submitted by: Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by: Kirk McKusick <mckusick@mckusick.com>
QUEUE_AGE, QUEUE_LRU, and QUEUE_EMPTY we instead have QUEUE_CLEAN,
QUEUE_DIRTY, QUEUE_EMPTY, and QUEUE_EMPTYKVA. With this patch clean
and dirty buffers have been separated. Empty buffers with KVM
assignments have been separated from truely empty buffers. getnewbuf()
has been rewritten and now operates in a 100% optimal fashion. That is,
it is able to find precisely the right kind of buffer it needs to
allocate a new buffer, defragment KVM, or to free-up an existing buffer
when the buffer cache is full (which is a steady-state situation for
the buffer cache).
Buffer flushing has been reorganized. Previously buffers were flushed
in the context of whatever process hit the conditions forcing buffer
flushing to occur. This resulted in processes blocking on conditions
unrelated to what they were doing. This also resulted in inappropriate
VFS stacking chains due to multiple processes getting stuck trying to
flush dirty buffers or due to a single process getting into a situation
where it might attempt to flush buffers recursively - a situation that
was only partially fixed in prior commits. We have added a new daemon
called the buf_daemon which is responsible for flushing dirty buffers
when the number of dirty buffers exceeds the vfs.hidirtybuffers limit.
This daemon attempts to dynamically adjust the rate at which dirty buffers
are flushed such that getnewbuf() calls (almost) never block.
The number of nbufs and amount of buffer space is now scaled past the
8MB limit that was previously imposed for systems with over 64MB of
memory, and the vfs.{lo,hi}dirtybuffers limits have been relaxed
somewhat. The number of physical buffers has been increased with the
intention that we will manage physical I/O differently in the future.
reassignbuf previously attempted to keep the dirtyblkhd list sorted which
could result in non-deterministic operation under certain conditions,
such as when a large number of dirty buffers are being managed. This
algorithm has been changed. reassignbuf now keeps buffers locally sorted
if it can do so cheaply, and otherwise gives up and adds buffers to
the head of the dirtyblkhd list. The new algorithm is deterministic but
not perfect. The new algorithm greatly reduces problems that previously
occured when write_behind was turned off in the system.
The P_FLSINPROG proc->p_flag bit has been replaced by the more descriptive
P_BUFEXHAUST bit. This bit allows processes working with filesystem
buffers to use available emergency reserves. Normal processes do not set
this bit and are not allowed to dig into emergency reserves. The purpose
of this bit is to avoid low-memory deadlocks.
A small race condition was fixed in getpbuf() in vm/vm_pager.c.
Submitted by: Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by: Kirk McKusick <mckusick@mckusick.com>
zero traps. I actually can't believe that this compiler is *sooooo* stupid
that it did a divide when there was 1024L*1024L instead of a right shift by
20. When we get quad type modifiers in kernel printf we can change to this
too (to avoid overflow on > terabyte disk sizes).
behavior slightly.
If machine/bus.h is included, but neither bus_memio.h nor bus_pio.h
are included, then behave as if both were included.
This won't change existing drivers, all of which include one or more
of bus_{p,mem}io.h, but will allow drivers from other systems to come
over with fewer changes. I freely admit that this might not be
optimal for some drivers, but those drivers can be optimized for
FreeBSD after the initial bringup happens.
Without the change, there is a bug that preclude drivers from
compiling with strange warning/errors.
I've been running this here for a while now w/o ill effects.
Reviewed by: gibbs
Not objected to by: bde, arch@ list.
On the VAX, it used to be used for special compilation to avoid the
optimizer which would mess with memory mapped devices etc. These days
we use 'volatile'.