Commit Graph

3 Commits

Author SHA1 Message Date
imp
20280f1431 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
phk
d999957bf0 Put the message about msgbuf cksum mismatch under bootverbose and tell
people what the consequence is.
2003-09-05 11:12:00 +00:00
iedowse
6bb0e5cb46 Replace the code for reading and writing the kernel message buffer
with a new implementation that has a mostly reentrant "addchar"
routine, supports multiple message buffers in the kernel, and hides
the implementation details from callers.

The new code uses a kind of sequence number to represend the current
read and write positions in the buffer. This approach (suggested
mainly by bde) permits the read and write pointers to be maintained
separately, which reduces the number of atomic operations that are
required. The "mostly reentrant" above refers to the way that while
it is now always safe to have any number of concurrent writers,
readers could see the message buffer after a writer has advanced
the pointers but before it has witten the new character.

Discussed on:	freebsd-arch
2003-06-22 02:18:31 +00:00