Add a new private thread flag to indicate that the thread should
not sleep if runningbufspace is too large.
Set this flag on the bufdaemon and syncer threads so that they skip
the waitrunningbufspace() call in bufwrite() rather than than
checking the proc pointer vs. the known proc pointers for these two
threads. A way of preventing these threads from being starved for
I/O but still placing limits on their outstanding I/O would be
desirable.
Set this flag in ffs_copyonwrite() to prevent bufwrite() calls from
blocking on the runningbufspace check while holding snaplk. This
prevents snaplk from being held for an arbitrarily long period of
time if runningbufspace is high and greatly reduces the contention
for snaplk. The disadvantage is that ffs_copyonwrite() can start
a large amount of I/O if there are a large number of snapshots,
which could cause a deadlock in other parts of the code.
Call runningbufwakeup() in ffs_copyonwrite() to decrement runningbufspace
before attempting to grab snaplk so that I/O requests waiting on
snaplk are not counted in runningbufspace as being in-progress.
Increment runningbufspace again before actually launching the
original I/O request.
Prior to the above two changes, the system could deadlock if enough
I/O requests were blocked by snaplk to prevent runningbufspace from
falling below lorunningspace and one of the bawrite() calls in
ffs_copyonwrite() blocked in waitrunningbufspace() while holding
snaplk.
See <http://www.holm.cc/stress/log/cons143.html>
introduce "-tunnel" as an alias for "deletetunnel".
The latter is overly long and prone to typos, but
keep it for POLA since it costs nothing.
MFC after: 5 days
the directory's inode after queuing the dirrem that will decrement
the parent directory's link count. This will force the update of
the parent directory's actual link to actually be scheduled. Without
this change the parent directory's actual link count would not be
updated until ufs_inactive() cleared the inode of the newly removed
directory, which might be deferred indefinitely. ufs_inactive()
will not be called as long as any process holds a reference to the
removed directory, and ufs_inactive() will not clear the inode if
the link count is non-zero, which could be the result of an earlier
system crash.
If a background fsck is run before the update of the parent directory's
actual link count has been performed, or at least scheduled by
putting the dirrem on the leaf directory's inodedep id_bufwait list,
fsck will corrupt the file system by decrementing the parent
directory's effective link count, which was previously correct
because it already took the removal of the leaf directory into
account, and setting the actual link count to the same value as the
effective link count after the dangling, removed, leaf directory
has been removed. This happens because fsck acts based on the
actual link count, which will be too high when fsck creates the
file system snapshot that it references.
This change has the fortunate side effect of more quickly cleaning
up the large number dirrem structures that linger for an extended
time after the removal of a large directory tree. It also fixes a
potential problem with the shutdown of the syncer thread timing out
if the system is rebooted immediately after removing a large directory
tree.
Submitted by: tegge
MFC after: 3 days
earlier, and more gracefully. Previously, this combination would be
ignored early in the code where permissions are tested and fail later
with a very unhelpful "permission denied" error.
Instead, test for this flag in the same block that generates the
"override?" messages for read-only files, but instead of trying
to guess what the user has in mind, generate an error and exit.
Update the man page to reflect this new behavior.
Not objected to by: freebsd-hackers@
interrupt handler from Alpha. Instead, expand the scheduler pinning
in the interrupt handling code so that curthread is pinned while executing
fast interrupt handlers.
MFC after: 1 week
the softc.
- Use callout_init_mtx() and rather than timeout/untimeout in both rl(4)
and re(4).
- Fix locking for ifmedia by locking the driver in the ifmedia handlers
rather than in the miibus functions. (re(4) didn't lock the mii stuff
at all!)
- Fix some locking in re_ioctl().
Note: the two drivers share the same softc declared in if_rlreg.h, so they
had to be change simultaneously.
MFC after: 1 week
Tested by: several on rl(4), none on re(4)
routing, etc. in a static pci_assign_interrupt() function.
- Add a sledgehammer that allows the user to override the interrupt
assignment of any PCI device via a tunable (e.g. "hw.pci0.7.INTB=5" would
force any functions on the pci device in slot 7 of bus 0 that use B# to
use IRQ 5). This should be used with great caution! Generally, if the
interrupt routing in use provides specific tunables (such as hard-wiring
the IRQ for a given $PIR or ACPI PCI link device), then those should be
used instead. One instance where this tunable might be useful is if a
box has an MPTable with duplicate entries for the same PCI device with
different IRQs.
MFC after: 1 week
the Intel 82371AB PCI-ISA bridge. We now do this all the time for the
!APIC case in the atpic driver. This cuts the raw line count for this
driver by about 40%.
MFC after: 1 week
There seems to be very little documentary evidence outside this
implementation to suggest a these checks are neccessary, and more
than one camera-formatted flash disk fails the check, but mounts
successfully on most other systems.
Reviewed By: bde@
make function reenterable. In the runtime the race is masked by serializing
of em_process_receive_interrupts() either by interrupt thread, or by
polling. The race can be triggered when polling is switched on or off.
bio may have been freed and reassigned by the wakeup before being
tested after releasing the bdonelock.
There's a non-zero chance this is the cause of a few of the crashes
knocking around with biodone() sitting in the stack backtrace.
Reviewed By: phk@
I'm able to suspend/resume my laptop without this change, but then I need
to wait for the watchdog to reset the card.
With this change, it is ready immediately.
Glanced at by: glebius
- typos
- different spelling, punctuation, whitespace
- phonetically similar names
- words rearranged ("was once" vs "once was" etc)
If a limerick appeared as a single one and as part of a
double or triple, the singleton was removed.
With a little help from: sort limerick|uniq -d
This still turns up 20 lines being repeated, but the respective
limericks are sufficiently unique to leave them in (i.e. most differ
in at least two lines).
Nuke spaces in front of colons while I'm here.
subdrivers to hook up.
It should probably be rewritten to implement a simple bus to which
the sub drivers attach using some kind of hint.
Until then, provide a couple of crutch functions with big warning
signs so it can survive the recent changes to struct resource.
can be enabled by enabling COUNT_IPIS in smptests.h. When enabled, each
CPU provides an interrupt counter for nearly all of the IPIs it receives
(IPI_STOP currently doesn't have a counter) that can be examined using
vmstat -i, etc.
MFC after: 3 days
Requested by: rwatson
on big-endian archs like sparc64, e.g.:
uart0: <16550 or compatible> at port 0x3f8-0x3ff irq 43 pnpid @HEd041 on isa0
is now correctly printed as:
uart0: <16550 or compatible> at port 0x3f8-0x3ff irq 43 pnpid PNP0501 on isa0
There are probably other endianness issues lurking in the PnP code which
however aren't exhibited on sparc64 as the PnP devices there are sort of
PnP BIOS devices rather than ISA PnP devices.
Tested on: i386, sparc64
MFC after: 1 week
and do some preparations for handling 12x22 fonts (currently lots of code
implies and/or hardcodes a font width of 8 pixels). This will be required
on sparc64 which uses a default font size of 12x22 in order to add font
loading and saving support as well as to use a syscons(4)-supplied mouse
pointer image.
This API breakage is committed now so it can be MFC'ed in time for 6.0
and later on upcoming framebuffer drivers destined for use on sparc64
and which are expected to rely on using font loading internally and on
a syscons(4)-supplied mouse pointer image can be easily MFC'ed to
RELENG_6 rather than requiring a backport.
Tested on: i386, sparc64, make universe
MFC after: 1 week
