fixes for previous version of new pipes from Bruce Evans. This
new version:
Supports more properly the semantics of select (BDE).
Supports "OLD_PIPE" correctly (kern_descrip.c, BDE).
Eliminates incorrect EPIPE returns (bash 'pipe broken' messages.)
Much faster yet, currently tuned relatively conservatively -- but now
gives approx 50% more perf than the new pipes code did originally.
(That was about 50% more perf than the original BSD pipe code.)
Known bugs outstanding:
No support for async io (SIGIO). Will be included soon.
Next to do:
Merge support for FIFOs.
Submitted by: bde
The code outputs the dc then calls the device specific externalize
routines to fill in the dc_data area. The old code assumed that dc_data
started one byte from the end of the dc, but with the compiler optimizing
alignment and padding, this isn't always the case. Do an explicit
&(dc.dc_data) - &dc. This fixes lsdev -c which must have been broken
for some time.
1) The calculation didn't account for NMBCLUSTERS, so if a large number of
clusters was specified, it would leave little or no space for kernel
malloc.
2) It was bogusly restricted to v_page_count. This doesn't take into
account the sparseness of the malloc area and would have caused
problems on machines with small amounts of memory. It should probably
instead be changed to set the malloc limit to be constrained by
the amount of memory, but I didn't do this.
First attempt at creating devfs entries for sliced devices. Doesn't
quite work yet, so the heart of it is disabled.
Added bdev and cdev args to dsopen().
Create devfs entries in dsopen() and (unsuccessfully) attempt to make
them go away at the right times. DEVFS is #undefed at the start so
that this shouldn't cause problems.
PT_ATTACH/PT_DETACH implemented now and fully operational.
PT_{GET|SET}{REGS|FPREFS} implemented now, using code shared with procfs
PT_{READ|WRITE}_{I|D} now uses code shared with procfs
ptrace opcodes now fully permission checked, including ownerships.
doing an operation to the u-area on a swapped process should no longer
panic.
running gdb as root works for me now, where it didn't before.
general cleanup..
Note, that this has some tightening of permissions/access checks etc.
Some of these may be going too far.. In particular, the "owner" of the
traced process is enforced. The process that created or attached to
the traced process is now the only one that can "do" things to it.
Speed up for vfs_bio -- addition of a routine bqrelse to greatly diminish
overhead for merged cache.
Efficiency improvement for vfs_cluster. It used to do alot of redundant
calls to cluster_rbuild.
Correct the ordering for vrele of .text and release of credentials.
Use the selective tlb update for 486/586/P6.
Numerous fixes to the size of objects allocated for files. Additionally,
fixes in the various pagers.
Fixes for proper positioning of vnode_pager_setsize in msdosfs and ext2fs.
Fixes in the swap pager for exhausted resources. The pageout code
will not as readily thrash.
Change the page queue flags (PG_ACTIVE, PG_INACTIVE, PG_FREE, PG_CACHE) into
page queue indices (PQ_ACTIVE, PQ_INACTIVE, PQ_FREE, PQ_CACHE),
thereby improving efficiency of several routines.
Eliminate even more unnecessary vm_page_protect operations.
Significantly speed up process forks.
Make vm_object_page_clean more efficient, thereby eliminating the pause
that happens every 30seconds.
Make sequential clustered writes B_ASYNC instead of B_DELWRI even in the
case of filesystems mounted async.
Fix a panic with busy pages when write clustering is done for non-VMIO
buffers.
Add more features to the one remaining to handle the job:
+ signed quantity.
# alternate format
- left padding
* read width as next arg.
n numeric in (argument specified) default radix.
Fix the DDB debugger to use these.
Use vprintf in debug routine in pcvt.
The warnings from gcc may become more wrong and intolerable because
of this.
Warning: I have not checked the entire source for unsupported or
changed constructs, but generally belive that there are only a few.
Suggested by: bde
sysv_ipc.c: add stub functions that either simply return (for the hooks
in kern_fork/kern_exit) or log() a messgae and call enosys() (for the
syscalls). sysv_ipc.c will become "standard" in conf/files and has
#ifs for all the permutations.
are about to go in. This is to fix the problem with the ibcs2 and linux
lkm's not being able to call the sysv ipc functions unless the build is
modified.
the range [210:260] by sweeping the problem under the rug. This change
has the following effects:
1) A new MIB variable in the kern branch is defined to allow modification
of the socket buffer layer's ``wastage factor'' (which determines how
much unused-but-allocated space in mbufs and mbuf clusters is allowed
in a socket buffer).
2) The default value of the wastage factor is changed from 2 to 8.
The original value was chosen when MINCLSIZE was 7*MLEN (!), and is not
appropriate for an environment where MINCLSIZE is much less.
The real solution to this problem is to scrap both mbufs and sockbufs
and completely redesign the buffering mechanism used at both levels.
