Re: [linux-audio-dev] low-latency scheduling patch for 2.4.0

New Message Reply About this list Date view Thread view Subject view Author view Other groups

Subject: Re: [linux-audio-dev] low-latency scheduling patch for 2.4.0
From: yodaiken_AT_fsmlabs.com
Date: Tue Jan 30 2001 - 22:51:54 EET

> The thing that really does concern me about the flash driver code is the
> fact that it often wants to wait for about 100µs. On machines with
> HZ==100, that sucks if you use udelay() and it sucks if you schedule(). So
> we end up dropping the spinlock (so at least bottom halves can run again)
> and calling:
>
> static inline void cfi_udelay(int us)
> {
> if (current->need_resched)
> schedule();
> else
> udelay(us);
> }

So then a >100us delay is ok ?

I have a dumb RT perspective: either you have to make the deadline or you don't.
If you have to make the deadline, then why are you checking need_resched? 

-- 
---------------------------------------------------------
Victor Yodaiken 
Finite State Machine Labs: The RTLinux Company.
 www.fsmlabs.com  www.rtlinux.com

New Message Reply About this list Date view Thread view Subject view Author view Other groups

This archive was generated by hypermail 2b28 : Wed Jan 31 2001 - 03:45:26 EET