CVS commit: src

[Andrew Doran <ad%netbsd.org@localhost>]

Module Name:    src
Committed By:   ad
Date:           Sun May 24 21:41:44 UTC 2009

Modified Files:
        src/dist/ipf/ipsend: sock.c
        src/usr.bin/fstat: fstat.c

Log Message:
More changes to improve kern_descrip.c.

- Avoid atomics in more places.
- Remove the per-descriptor mutex, and just use filedesc_t::fd_lock.
  It was only being used to synchronize close, and in any case we needed
  to take fd_lock to free the descriptor slot.
- Optimize certain paths for the <NDFDFILE case.
- Sprinkle more comments and assertions.
- Cache more stuff in filedesc_t.
- Fix numerous minor bugs spotted along the way.
- Restructure how the open files array is maintained, for clarity and so
  that we can eliminate the membar_consumer() call in fd_getfile().  This is
  mostly syntactic sugar; the main functional change is that fd_nfiles now
  lives alongside the open file array.

Some measurements with libmicro:

- simple file syscalls are like close() are between 1 to 10% faster.
- some nice improvements, e.g. poll(1000) which is ~50% faster.


To generate a diff of this commit:
cvs rdiff -u -r1.14 -r1.15 src/dist/ipf/ipsend/sock.c
cvs rdiff -u -r1.88 -r1.89 src/usr.bin/fstat/fstat.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.