read the same register back. It can cause hangs or machine
checks in certain cases. One particular case is with bge(4)
when a reset is initiated for the controller.
MFC after: 1 month
file system code (mostly *_reclaim()) which look like this:
VOP_LOCK(vp);
/* examine vp */
VOP_UNLOCK(vp);
vdrop(vp);
This can now be rewritten to:
VOP_LOCK(vp);
/* examine vp */
vdropl(vp); /* will unlock vp */
MFC after: 1 week
obtaining and releasing shared and exclusive locks. The algorithms for
manipulating the lock cookie are very similar to that rwlocks. This patch
also adds support for exclusive locks using the same algorithm as mutexes.
A new sx_init_flags() function has been added so that optional flags can be
specified to alter a given locks behavior. The flags include SX_DUPOK,
SX_NOWITNESS, SX_NOPROFILE, and SX_QUITE which are all identical in nature
to the similar flags for mutexes.
Adaptive spinning on select locks may be enabled by enabling the
ADAPTIVE_SX kernel option. Only locks initialized with the SX_ADAPTIVESPIN
flag via sx_init_flags() will adaptively spin.
The common cases for sx_slock(), sx_sunlock(), sx_xlock(), and sx_xunlock()
are now performed inline in non-debug kernels. As a result, <sys/sx.h> now
requires <sys/lock.h> to be included prior to <sys/sx.h>.
The new kernel option SX_NOINLINE can be used to disable the aforementioned
inlining in non-debug kernels.
The size of struct sx has changed, so the kernel ABI is probably greatly
disturbed.
MFC after: 1 month
Submitted by: attilio
Tested by: kris, pjd
discards it, for use when the compression layer code doesn't know how to
skip data (e.g., everything other than the "none" compressor). This makes
format level code simpler because that code can now assume that the
compression layer always knows how to skip and will always skip exactly
the requested number of bytes.
Discussed with: kientzle (3 months ago)
file. The previous commit fixed a bug in pci_pending_msix() where it
mis-calculated the word in the PBA to read to see if a message was
pending. Nothing actually uses pci_pending_msix() yet though, so this
didn't result in any visible problems.
MFC after: 1 week
Add entries for the six persons listed in the first version of
commit.allow in the old FreeBSD 1 CVS repo.
Correct joergs date, and link him to jkh.
Add my own entry.
explicitly test and panic. This should not ever happen, but if it does,
this is a preferred failure mode to a NULL pointer dereference in kernel.
Coverity CID: 1716
Found with: Coverity Prevent(tm)
