for code to start out on one CPU when thunking into Windows
mode in ctxsw_utow(), and then be pre-empted and migrated to another
CPU before thunking back to UNIX mode in ctxsw_wtou(). This is
bad, because then we can end up looking at the wrong 'thread environment
block' when trying to come back to UNIX mode. To avoid this, we now
pin ourselves to the current CPU when thunking into Windows code.
Few other cleanups, since I'm here:
- Get rid of the ndis_isr(), ndis_enable_interrupt() and
ndis_disable_interrupt() wrappers from kern_ndis.c and just invoke
the miniport's methods directly in the interrupt handling routines
in subr_ndis.c. We may as well lose the function call overhead,
since we don't need to export these things outside of ndis.ko
now anyway.
- Remove call to ndis_enable_interrupt() from ndis_init() in if_ndis.c.
We don't need to do it there anyway (the miniport init routine handles
it, if needed).
- Fix the logic in NdisWriteErrorLogEntry() a little.
- Change some NDIS_STATUS_xxx codes in subr_ntoskrnl.c into STATUS_xxx
codes.
- Handle kthread_create() failure correctly in PsCreateSystemThread().
based jumbo 9k and jumbo 16k cluster support.
All mbuf's with external storage attached are mandatory reference
counted. For clusters and jumbo clusters UMA provides the refcnt
storage directly. It does not have to be separatly allocated. Any
other type of external storage gets its own refcnt allocated from
an UMA mbuf refcnt zone instead of normal kernel malloc.
The refcount API MEXT_ADD_REF() and MEXT_REM_REF() is no longer
publically accessible. The proper m_* functions have to be used.
mb_ctor_clust() and mb_dtor_clust() both handle normal 2K as well
as 9k and 16k clusters.
Clusters and jumbo clusters may be obtained without attaching it
immideatly to an mbuf. This is for high performance cluster
allocation in network drivers where mbufs are attached after the
cluster has been filled.
Tested by: rwatson
Sponsored by: TCP/IP Optimizations Fundraise 2005
destruction:
- Backout 1.62, since it doesn't fix all possible
problems.
- Upon node creation, put an additional reference on node.
- Add a mutex and refcounter to struct ngsock. Netgraph node,
control socket and data socket all count as references.
- Introduce ng_socket_free_priv() which removes one reference
from ngsock, and frees it when all references has gone.
- No direct pointers between pcbs and node, all pointing
is done via struct ngsock and protected with mutex.
- Introduce ng_topo_mtx, a mutex to protect topology changes.
- In ng_destroy_node() protect with ng_topo_mtx the process
of checking and pointing at ng_deadnode. [1]
- In ng_con_part2() check that our peer is not a ng_deadnode,
and protect the check with ng_topo_mtx.
- Add KASSERTs to ng_acquire_read/write, to make more
understandible synopsis in case if called on ng_deadnode.
Reported by: Roselyn Lee [1]
- Introduce a new flags NGQF_QREADER and NGQF_QWRITER,
which tell how the item should be actually applied,
overriding NGQF_READER/NGQF_WRITER flags.
- Do not differ between pending reader or writer. Use only
one flag that is raised, when there are pending items.
- Schedule netgraph ISR in ng_queue_rw(), so that callers
do not need to do this job.
- Fix several comments.
Submitted by: julian
interface up when it is running AND the link is not down (that is, it is
up or unknown). If the interface is running but the link is down, we return
state 'dormant', because we're waiting for an external event. Otherwise
the interface is 'down'.
Submitted by: csjp
Reviewed by: glebius
so that it can be faster for tiny x and avoided for reduced x.
This improves things a little differently than for cosine and sine.
We still need to reclassify x in the "kernel" functions, but we get
an extra optimization for tiny x, and an overall optimization since
tiny reduced x rarely happens. We also get optimizations for space
and style. A large block of poorly duplicated code to fix a special
case is no longer needed. This supersedes the fixes in k_sin.c revs
1.9 and 1.11 and k_sinf.c 1.8 and 1.10.
Fixed wrong constant for the cutoff for "tiny" in tanf(). It was
2**-28, but should be almost the same as the cutoff in sinf() (2**-12).
The incorrect cutoff protected us from the bugs fixed in k_sinf.c 1.8
and 1.10, except 4 cases of reduced args passed the cutoff and needed
special handling in theory although not in practice. Now we essentially
use a cutoff of 0 for the case of reduced args, so we now have 0 special
args instead of 4.
This change makes no difference to the results for sinf() (since it
only changes the algorithm for the 4 special args and the results for
those happen not to change), but it changes lots of results for sin().
Exhaustive testing is impossible for sin(), but exhaustive testing
for sinf() (relative to a version with the old algorithm and a fixed
cutoff) shows that the changes in the error are either reductions or
from 0.5-epsilon ulps to 0.5+epsilon ulps. The new method just uses
some extra terms in approximations so it tends to give more accurate
results, and there are apparently no problems from having extra
accuracy. On amd64 with -O1, on all float args the error range in ulps
is reduced from (0.500, 0.665] to [0.335, 0.500) in 24168 cases and
increased from 0.500-epsilon to 0.500+epsilon in 24 cases. Non-
exhaustive testing by ucbtest shows no differences.
Having an additional MT_HEADER mbuf type is superfluous and redundant
as nothing depends on it. It only adds a layer of confusion. The
distinction between header mbuf's and data mbuf's is solely done
through the m->m_flags M_PKTHDR flag.
Non-native code is not changed in this commit. For compatibility
MT_HEADER is mapped to MT_DATA.
Sponsored by: TCP/IP Optimization Fundraise 2005
commit moved it). This includes a comment that the "kernel" sine no
longer works on arg -0, so callers must now handle this case. The kernel
sine still works on all other tiny args; without the optimization it is
just a little slower on these args. I intended it to keep working on
all tiny args, but that seems to be impossible without losing efficiency
or accuracy. (sin(x) ~ x * (1 + S1*x**2 + ...) would preserve -0, but
the approximation must be written as x + S1*x**3 + ... for accuracy.)
case never occurs since pi/2 is irrational so no multiple of it can
be represented as a float and we have precise arg reduction so we never
end up with a remainder of 0 in the "kernel" function unless the
original arg is 0.
If this case occurs, then we would now fall through to general code
that returns +-Inf (depending on the sign of the reduced arg) instead
of forcing +Inf. The correct handling would be to return NaN since
we would have lost so much precision that the correct result can be
anything _except_ +-Inf.
Don't reindent the else clause left over from this, although it was already
bogusly indented ("if (foo) return; else ..." just marches the indentation
to the right), since it will be removed too.
Index: k_tan.c
===================================================================
RCS file: /home/ncvs/src/lib/msun/src/k_tan.c,v
retrieving revision 1.10
diff -r1.10 k_tan.c
88,90c88
< if (((ix | low) | (iy + 1)) == 0)
< return one / fabs(x);
< else {
---
> {
a declaration was not translated to "float" although bit fiddling on
double variables was translated. This resulted in garbage being put
into the low word of one of the doubles instead of non-garbage being
put into the only word of the intended float. This had no effect on
any result because:
- with doubles, the algorithm for calculating -1/(x+y) is unnecessarily
complicated. Just returning -1/((double)x+y) would work, and the
misdeclaration gave something like that except for messing up some
low bits with the bit fiddling.
- doubles have plenty of bits to spare so messing up some of the low
bits is unlikely to matter.
- due to other bugs, the buggy code is reached for a whole 4 args out
of all 2**32 float args. The bug fixed by 1.8 only affects a small
percentage of cases and a small percentage of 4 is 0. The 4 args
happen to cause no problems without 1.8, so they are even less likely
to be affected by the bug in 1.8 than average args; in fact, neither
1.8 nor this commit makes any difference to the result for these 4
args (and thus for all args).
Corrections to the log message in 1.8: the bug only applies to tan()
and not tanf(), not because the float type can't represent numbers
large enough to trigger the problem (e.g., the example in the fdlibm-5.3
readme which is > 1.0e269), but because:
- the float type can't represent small enough numbers. For there to be
a possible problem, the original arg for tanf() must lie very near an
odd multiple of pi/2. Doubles can get nearer in absolute units. In
ulps there should be little difference, but ...
- ... the cutoff for "small" numbers is bogus in k_tanf.c. It is still
the double value (2**-28). Since this is 32 times smaller than
FLT_EPSILON and large float values are not very uniformly distributed,
only 6 args other than ones that are initially below the cutoff give
a reduced arg that passes the cutoff (the 4 problem cases mentioned
above and 2 non-problem cases).
Fixing the cutoff makes the bug affect tanf() and much easier to detect
than for tan(). With a cutoff of 2**-12 on amd64 with -O1, 670102
args pass the cutoff; of these, there are 337604 cases where there
might be an error of >= 1 ulp and 5826 cases where there is such an
error; the maximum error is 1.5382 ulps.
The fix in 1.8 works with the reduced cutoff in all cases despite the
bug in it. It changes the result in 84492 cases altogether to fix the
5826 broken cases. Fixing the fix by translating "double" to "float"
changes the result in 42 cases relative to 1.8. In 24 cases the
(absolute) error is increased and in 18 cases it is reduced, but it
remains less than 1 ulp in all cases.
field holding the threadid. This is more useful for libthr than
libpthread, but still quite useful in libpthread as it can be used to
process interlaced records from multiple threads over the course of a
system call.
Detect old ktr_buffer values using the heuristic "if it's negative,
then it must not be a valid threadid". This may leave something to be
desired.
MFC after: 1 month
Reviewed by: davidxu
ktr_tid as part of gathering of ktr header data for new ktrace
records. The continued use of intptr_t is required for file layout
reasons, and cannot be changed to lwpid_t at this point.
MFC after: 1 month
Reviewed by: davidxu
intptr_t. The buffer length needs to be written to disk as part
of the trace log, but the kernel pointer for the buffer does not.
Add a new ktr_buffer pointer to the kernel-only ktrace request
structure to hold that pointer. This frees up an integer in the
ktrace record format that can be used to hold the threadid,
although older ktrace files will have a garbage ktr_buffer field
(or more accurately, a kernel pointer value).
MFC after: 2 weeks
Space requested by: davidxu
rewritten, now timers created with same sigev_notify_attributes will
run in same thread, this allows user to organize which timers can
run in same thread to save some thread resource.
This causes attempts to update a non-existent file to report
an actual error instead of triggering an assertion failure.
PR: bin/87911
Thanks to: roemer.ulrich
MFC after: 3 days
Note: This does not entirely fix bin/87911. I need to decide on
the "correct" response when someone tries to update a non-existent
archive file.
If a copy-on-write fault occurs on the page, the new copy should inherit
a part of the original page's wire count.
Submitted by: tegge
MFC after: 1 week
