Commit Graph

3 Commits

Author SHA1 Message Date
Colin Percival
1c81bd2c60 style cleanup: Remove duplicate $FreeBSD$ tags.
These files had tags after teh copyright notice,
inside the comment block (incorrect, removed),
and outside the comment block (correct).

Approved by:	rwatson (mentor)
2004-02-10 20:45:28 +00:00
Marcel Moolenaar
f8739dd5f9 Implement the lock with a cmpxchg instruction instead of a xchg.
Both are atomic, but the cmpxchg has memory ordering hints. We
give this acquire semantics.

NOTE: The unlock in libc_r is implemented by a "normal" assign
statement. This is not correct on ia64 due to the memory ordering
characteristics of the architecture. We need release semantics
for an unlock.
2002-11-16 17:05:06 +00:00
Peter Wemm
7657553c76 Add an ia64 atomic lock primitive for libc_r. This is mostly for
completeness and doesn't get us a working libc_r there because libc_r
uses setjmp() and setjmp() cannot be used for context switches on ia64
as-is (or sparc64).  Rather than making setjmp/longjmp behave like
the *context() calls, it would be far better to make libc_r use *context()
directly which is what they are for.

Obtained from:  marcel
2002-07-20 19:22:10 +00:00