long filename. Each substring is indexed by the windows ID, a
sequential one-based value. The previous code was extremely slow,
doing a malloc/strcpy/free for each substring.
This code optimizes these routines with this in mind, using the ID
to index into a single array and concatenating each WIN_CHARS chunk
at once. (The last chunk is variable-length.)
This code has been tested as working on an FS with difficult filename
sizes (255, 13, 26, etc.) It gives a 77.1% decrease in profiled
time (total across all functions) and a 73.7% decrease in wall time.
Test was "ls -laR > /dev/null".
Per-function time savings:
mbnambuf_init: -90.7%
mbnambuf_write: -18.7%
mbnambuf_flush: -67.1%
MFC after: 1 month
socket lock around knlist_init(), so don't.
Hard code the setting of the socket reference count to 1 rather than
using soref() to avoid asserting the socket lock, since we've not yet
exposed the socket to other threads.
This removes two mutex operations from each socket allocation.
so that the socket does not generate SIGPIPE, only EPIPE, when a write
is attempted after socket shutdown. When the option was introduced in
2002, this required the logic for determining whether SIGPIPE was
generated to be pushed down from dofilewrite() to the socket layer so
that the socket options could be considered. However, the change in
2002 omitted modification to soo_write() required to add that logic,
resulting in SIGPIPE not being generated even without SO_NOSIGPIPE when
the socket was written to using write() or related generic system calls.
This change adds the EPIPE logic to soo_write(), generating a SIGPIPE
signal to the process associated with the passed uio in the event that
the SO_NOSIGPIPE option is not set.
Notes:
- The are upsides and downsides to placing this logic in the socket
layer as opposed to the file descriptor layer. This is really fd
layer logic, but because we need so_options, we have a choice of
layering violations and pick this one.
- SIGPIPE possibly should be delivered to the thread performing the
write, not the process performing the write.
- uio->uio_td and the td argument to soo_write() might potentially
differ; we use the thread in the uio argument.
- The "sigpipe" regression test in src/tools/regression/sockets/sigpipe
tests for the bug.
Submitted by: Mikko Tyolajarvi <mbsd at pacbell dot net>
Talked with: glebius, alfred
PR: 78478
MFC after: 1 week
intended to verify that SIGPIPE is delivered to a process writing or
sending on a socket that has been shut down for write. If available,
SO_NOSIGPIPE is also tested.
This regression test is currently passed by RELENG_4, but not by HEAD or
RELENG_5, due to a bug in the write() code for sockets. SO_NOSIGPIPE is not
present in RELENG_4, however, so is not tested there.
Reported by: Mikko Tyolajarvi <mbsd at pacbell dot net>
PR: 78478
patch differs from the previous one in that it calls the function
only when a real file hits EOF. The bodies of .for loops are also
handled as files, but for these we don't want to end a dependency block
on the 'EOF' as in:
foo:
do-this
.for ...
do-something
.endfor
do-more
to syncrhonize access to the data as a result. This makes the pps
less likely to miss the 1ms pulse that I'm feeding it, but not
entirely reliable yet on my 133MHz P5.
Reviewed by: phk
unknown (since my sony vaio didn't :-(.
Instead, fix the problem described by 1.49 in a different way: just
add the two calls I'd hoped I'd avoid in 1.49 by doing the (wrong)
gymnastics there. While 1.49 is a good direction to go in, each step
of the way should work :-(.
This allows us to:
- perform scatter gather operations without using temporary files,
- create non-linear pipelines, and
- implement file views using symbolic links.
File view idea by: Vassilios Karakoidas
Portalfs pointer by: John Ioannidis
MFC after: 1 month