On Mon, 8 Jan 2001, Kevin D. Kissell wrote: > Back in the Ancient Old Days of System V, every architecture > had an architecture-specific system call entry, the first parameter > of which expressed what needed to be done. Do we have > such a thing in Linux? That would be the logical place to > things like cache flush and the atomic operations that were > being discussed here a couple of weeks ago. The only case caches need to be synchronized is modifying some code. The ptrace syscall does it automatically for text writes -- it's needed and used by gdb to set breakpoints, for example. For other code there is cacheflush() which allows you to flush a cache range relevant to a given virtual address (I see it's not implemented very well at the moment). Obviously, you don't want to allow unprivileged users to flush caches as a whole as it could lead to a DoS. -- + Maciej W. Rozycki, Technical University of Gdansk, Poland + +--------------------------------------------------------------+ + e-mail: macro@ds2.pg.gda.pl, PGP key available +
