[lkml]   [2002]   [Feb]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [RFC] New locking primitive for 2.5

On Fri, 8 Feb 2002, Ingo Molnar wrote:
> and regarding the reintroduction of BKL, *please* do not just use a global
> locks around such pieces of code, lock bouncing sucks on SMP, even if
> there is no overhead.

I'd suggest not having a lock at all, but instead add two functions: one
to read a 64-bit value atomically, the other to write it atomically (and
they'd be atomic only wrt each other, no memory barriers etc implied).

On 64-bit architectures that's just a direct dereference, and even on x86
it's just a "cmpxchg8b".


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:24    [W:0.088 / U:0.088 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site