On Tue, May 31, 2016 at 04:49:00AM +0200, Steffen Nurpmeso wrote:
> Joerg Sonnenberger wrote:
> |On Mon, May 30, 2016 at 02:19:26PM -0700, Charles Cui wrote:
> |> good to know atomic_inc_uint_nv is implemented using cas.
> |
> |No, atomic_inc is *not* necessarily implemented using CAS. There a
Joerg Sonnenberger wrote:
|On Mon, May 30, 2016 at 02:19:26PM -0700, Charles Cui wrote:
|> good to know atomic_inc_uint_nv is implemented using cas.
|
|No, atomic_inc is *not* necessarily implemented using CAS. There are a
What a pity.
|couple of different ways to do it ranging from implici
On Mon, May 30, 2016 at 02:19:26PM -0700, Charles Cui wrote:
> good to know atomic_inc_uint_nv is implemented using cas.
No, atomic_inc is *not* necessarily implemented using CAS. There are a
couple of different ways to do it ranging from implicit serialisation on
UP-only systems over CAS/LL-SC lo
good to know atomic_inc_uint_nv is implemented using cas.
I will update the patch and send you guys later (being careful about the
format)
Thanks Charles
2016-05-30 13:46 GMT-07:00 Christos Zoulas :
> On May 30, 1:43pm, charles.cui1...@gmail.com (Charles Cui) wrote:
> -- Subject: Re: pthread li
I am not familiar with _nv() (are there examples in the netbsd code base? I
searched _nv() in nxr, but did not found anything meaningful.),
but if you want to use atomic operations, one possible way is
compare-and-swap (CAS).
it has stronger guarantee than atomic inc or atomic dec, but also larger
No, using atomic_inc / atomic_dec for p_nsem is wrong!
Let's think about the multithreading case. Let's use 2 threads A and B in
the same process as an example. Assume p_nsem is not reaching the limit,
but only one slot is left.
A and B will each read the p_nsem separately. There will be probabi
