freebsd stable - Feb 2016 - 82576 + NETMAP + VLAN

On Thu, Oct 22, 2015 at 11:24:53AM -0700, Luigi Rizzo wrote:
> On Thu, Oct 22, 2015 at 11:12 AM, Adrian Chadd <adrian.chadd at
gmail.com> wrote:
> > On 22 October 2015 at 09:35, Slawa Olhovchenkov <slw at
zxy.spb.ru> wrote:
> >> On Sun, Oct 18, 2015 at 07:45:52PM -0700, Adrian Chadd wrote:
> >>
> >>> Heh, file a bug with luigi; it should be defined better inside
netmap itself.
> >>
> >> I am CC: luigi.
> >>
> >> Next question: do kevent RX/TX sync?
> >> In my setup I am need to manual NIOCTXSYNC/NIOCRXSYNC.
> >
> > Hi,
> >
> > Nope. kqueue() doesn't do the implicit sync like poll() does;
it's
> > just the notification path.
> 
> actually not. When the file descriptor is registered there
> is an implicit sync, and there is another one when an event
> is posted for the file descriptor.
> 
> unless there are bugs, of course.
I found strange behaivor:

1. open netmap and register in main thread
2. kevent register in different thread
3. result: got event by kevent but no ring sinc (all head,tail,cur
still 0).

Is this normal? Or is this bug?

open and registering netmap in same thread as kevent resolve this.

On Tue, Feb 02, 2016 at 11:44:47PM +0300, Slawa Olhovchenkov wrote:
> On Thu, Oct 22, 2015 at 11:24:53AM -0700, Luigi Rizzo wrote:
> 
> > On Thu, Oct 22, 2015 at 11:12 AM, Adrian Chadd <adrian.chadd at
gmail.com> wrote:
> > > On 22 October 2015 at 09:35, Slawa Olhovchenkov <slw at
zxy.spb.ru> wrote:
> > >> On Sun, Oct 18, 2015 at 07:45:52PM -0700, Adrian Chadd wrote:
> > >>
> > >>> Heh, file a bug with luigi; it should be defined better
inside netmap itself.
> > >>
> > >> I am CC: luigi.
> > >>
> > >> Next question: do kevent RX/TX sync?
> > >> In my setup I am need to manual NIOCTXSYNC/NIOCRXSYNC.
> > >
> > > Hi,
> > >
> > > Nope. kqueue() doesn't do the implicit sync like poll() does;
it's
> > > just the notification path.
> > 
> > actually not. When the file descriptor is registered there
> > is an implicit sync, and there is another one when an event
> > is posted for the file descriptor.
> > 
> > unless there are bugs, of course.
> 
> I found strange behaivor:
> 
> 1. open netmap and register in main thread
> 2. kevent register in different thread
> 3. result: got event by kevent but no ring sinc (all head,tail,cur
> still 0).
> 
> Is this normal? Or is this bug?
> 
> open and registering netmap in same thread as kevent resolve this.
Also, kevent+netmap deadlocked for me:

  PID    TID COMM             TDNAME           KSTACK                       
 1095 100207 addos            -                mi_switch+0xe1
sleepq_catch_signals+0xab sleepq_timedwait_sig+0x10 _sleep+0x238
kern_nanosleep+0x10e sys_nanosleep+0x51 amd64_syscall+0x40f Xfast_syscall+0xfb
 1095 100208 addos            worker#0         mi_switch+0xe1
sleepq_catch_signals+0xab sleepq_wait_sig+0xf _sleep+0x27d kern_kevent+0x401
sys_kevent+0x12a amd64_syscall+0x40f Xfast_syscall+0xfb
 1095 100209 addos            worker#1         mi_switch+0xe1
turnstile_wait+0x42a __mtx_lock_sleep+0x26b knote+0x38 freebsd_selwakeup+0x8b
netmap_notify+0x55 netmap_pipe_txsync+0x156 netmap_poll+0x400 netmap_knrw+0x6e
kqueue_register+0x799 kern_kevent+0x158 sys_kevent+0x12a amd64_syscall+0x40f
Xfast_syscall+0xfb
 1095 100210 addos            worker#2         mi_switch+0xe1
sleepq_catch_signals+0xab sleepq_wait_sig+0xf _sleep+0x27d kern_kevent+0x401
sys_kevent+0x12a amd64_syscall+0x40f Xfast_syscall+0xfb
 1095 100211 addos            worker#NOIP      mi_switch+0xe1
sleepq_catch_signals+0xab sleepq_wait_sig+0xf _sleep+0x27d kern_kevent+0x401
sys_kevent+0x12a amd64_syscall+0x40f Xfast_syscall+0xfb
 1095 100212 addos            balancer         mi_switch+0xe1
turnstile_wait+0x42a __mtx_lock_sleep+0x26b knote+0x38 freebsd_selwakeup+0x8b
netmap_notify+0x2a netmap_pipe_rxsync+0x54 netmap_poll+0x774 netmap_knrw+0x6e
kern_kevent+0x5cc sys_kevent+0x12a amd64_syscall+0x40f Xfast_syscall+0xfb