Re: Why Semaphore Hardware-Dependent?

[David Howells]

Ralf Baechle <ralf@xxxxxxxxxxxxxx> wrote:

> > Which arches do not support cmpxchg?
> 
> MIPS, Alpha - probably any pure RISC load/store architecture.

Some of these have LL/SC or equivalent instead, but ARM5 and before, FRV, M68K
before 68020 to name but a few.

And anything that implements CMPXCHG with spinlocks is a really bad candidate
for CMPXCHG-based rwsems.

David
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/