Messages in this thread | | | Date | Wed, 29 Nov 2006 14:54:25 +0000 | From | Christoph Hellwig <> | Subject | Re: [PATCH -mm 3/5][AIO] - export good_sigevent() |
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> +/*** > + * good_sigevent - check and get target task from a sigevent. > + * @event: the sigevent to be checked > + * > + * This function must be called with tasklist_lock held for reading. > + */ > +struct task_struct * good_sigevent(sigevent_t * event) > +{ > + struct task_struct *rtn = current->group_leader; > + > + if ((event->sigev_notify & SIGEV_THREAD_ID ) && > + (!(rtn = find_task_by_pid(event->sigev_notify_thread_id)) || > + rtn->tgid != current->tgid || > + (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL)) > + return NULL; > + > + if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) && > + ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX))) > + return NULL; > + > + return rtn; > +}
And while we're at it we should badly beat up the person that wrote this mess in the first time. To be somewhat readable it should look like:
static struct task_struct *good_sigevent(sigevent_t *event) { struct task_struct *task = current->group_leader;
if ((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) { if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX) return NULL; }
if (event->sigev_notify & SIGEV_THREAD_ID) { if ((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL) return NULL; task = find_task_by_pid(event->sigev_notify_thread_id); if (!task || task->tgid != current->tgid) return NULL; }
return task; }
And btw, looking at its currentl caller I see why we need the PF_EXITING flag I recommended to remove easiler on, it even has a big comment that we should copy & paste to aio.c aswell. Still no idea why it's doing the selectiv reference grabbing, though. - 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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