On Thu, May 22, 2014 at 01:06:22PM +0200, Hans Petter Selasky wrote: > Hi, > > When using the Linux Skype client under FreeBSD I sometimes see that the > Audio disappears in the one direction. When I check "ps auxw" I see > skype is stuck on a so-called Futex. I looked into the Linux futex code > and see that wakeup_one() is used instead of wakeup(). Maybe others can > test too and verify if replacing wakeup_one() by wakeup() makes any > difference in for Linux applications using Futexes. > generally speaking the patch is not correct as futex_wake() should wakeup n waiters which is specified by user space. and i think that futex_wake() is correct. so we must take a close look at futex_requeue() and FUTEX_WAKE_OP. > --HPS > > > > diff --git a/sys/compat/linux/linux_futex.c b/sys/compat/linux/linux_futex.c > > index 9b4c92f..e893bf4 100644 > > --- a/sys/compat/linux/linux_futex.c > > +++ b/sys/compat/linux/linux_futex.c > > _at__at_ -498,7 +498,7 _at__at_ futex_wake(struct futex *f, int n, uint32_t bitset) > > wp->wp_flags |= FUTEX_WP_REMOVED; > > TAILQ_REMOVE(&f->f_waiting_proc, wp, wp_list); > > LIN_SDT_PROBE1(futex, futex_wake, wakeup, wp); > > - wakeup_one(wp); > > + wakeup(wp); > > if (++count == n) > > break; > > } > > _at__at_ -525,7 +525,7 _at__at_ futex_requeue(struct futex *f, int n, struct futex *f2, int n2) > > wp->wp_flags |= FUTEX_WP_REMOVED; > > TAILQ_REMOVE(&f->f_waiting_proc, wp, wp_list); > > LIN_SDT_PROBE1(futex, futex_requeue, wakeup, wp); > > - wakeup_one(wp); > > + wakeup(wp); > > } else { > > LIN_SDT_PROBE3(futex, futex_requeue, requeue, > > f->f_uaddr, wp, f2->f_uaddr); > > _______________________________________________ > freebsd-current_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org" -- Have fun! chd
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