2014-04-11 11:41, Olivier MATZ: > On Thursday, April 03, 2014 07:35:50 AM Hiroshi Shimamoto wrote: > > From: Hiroshi Shimamoto <h-shimamoto at ct.jp.nec.com> > > > > Same as PMD, there is a race condition between host and guest > > in the guest MEMNIC kernel driver. > > > > Guest PMD Host > > Thread-A Thread-B vSwitch > > > > |idx=0 |idx=0 |p[0] st!=2 > > |cmpxchg | | > > |p[0] st->1 | | > > |idx=1 | | > > |fill data | | > > |p[0] st->2 | |p[0] st==2 > > | > > | | |receive data > > | | |p[0] st->0 > > | | > > | |cmpxchg | > > | |success |p[1] st!=2 > > | |p[0] st->1 | > > | | > > This is BAD > > > > Signed-off-by: Hiroshi Shimamoto <h-shimamoto at ct.jp.nec.com> > > --- > > > > linux/memnic_net.c | 9 +++++++++ > > 1 file changed, 9 insertions(+) > > Reviewed-by: Olivier Matz <olivier.matz at 6wind.com>
Applied Thanks -- Thomas
