Re: No SIGIO for fifos in the file system? (gpm vs. xfree86-4.0)

From: Paul Barton-Davis (pbd@Op.Net)
Date: Tue Apr 25 2000 - 20:02:52 EST

Manfred Spraul <> wrote:

>fasync_helper() uses cli() for the synchronization, and I have some
>doubts that this is really SMP safe:
>* it seems that the keyboard drivers use tasklets, and cli() doesn't
>stop tasklets.
>* someone might call kill_fasync() from process context, then cli() is
>not enough.
>fasync outside net should be fairly rare, I guess one global rwlock is

from drivers/char/rtc.c, a case that I rely on a *great* deal:

  static int rtc_fasync (int fd, struct file *filp, int on)
          return fasync_helper (fd, filp, on, &rtc_async_queue);

since it lets SCHED_FIFO tasks have better timing performance than the
kernel provides by itself.


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This archive was generated by hypermail 2b29 : Sun Apr 30 2000 - 21:00:10 EST