Messages in this thread | | | Date | Wed, 24 Jan 2007 12:11:30 +0100 | From | Sébastien Dugué <> | Subject | Re: [PATCH -mm 4/5][AIO] - AIO completion signal notification |
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On Tue, 23 Jan 2007 21:35:13 -0800 Andrew Morton <akpm@osdl.org> wrote:
> On Wed, 17 Jan 2007 10:50:18 +0100 > Sébastien Dugué <sebastien.dugue@bull.net> wrote: > > > +static long aio_setup_sigevent(struct aio_notify *notify, > > + struct sigevent __user *user_event) > > +{ > > + sigevent_t event; > > + struct task_struct *target; > > + > > + if (copy_from_user(&event, user_event, sizeof (event))) > > + return -EFAULT; > > + > > + if (event.sigev_notify == SIGEV_NONE) > > + return 0; > > + > > + notify->notify = event.sigev_notify; > > + notify->signo = event.sigev_signo; > > + notify->value = event.sigev_value; > > + > > + read_lock(&tasklist_lock); > > + target = good_sigevent(&event); > > + > > + if (unlikely(!target || (target->flags & PF_EXITING))) > > + goto out_unlock; > > + > > + /* > > + * At this point, we know that notify is either SIGEV_SIGNAL or > > + * SIGEV_THREAD_ID and the target task is valid. So get a reference > > + * on the task, it will be dropped in really_put_req() when > > + * we're done with the request. > > + */ > > + get_task_struct(target); > > + notify->target = target; > > + read_unlock(&tasklist_lock); > > + > > + /* > > + * NOTE: we cannot free the sigqueue in the completion path as > > + * the signal may not have been delivered to the target task. > > + * Therefore it has to be freed in __sigqueue_free() when the > > + * signal is collected if si_code is SI_ASYNCIO. > > + */ > > + notify->sigq = sigqueue_alloc(); > > + > > + if (unlikely(!notify->sigq)) > > + return -EAGAIN; > > Did this just leak a ref on the task_struct? >
No, the ref is released in really_put_req() when we dispose of the iocb.
Thanks,
Sébastien. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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