On Mon, Feb 17, 2003 at 11:48:28PM +0100, Emard wrote: > > you must not use semaphores but spinlocks for locking data accessed from > > irq handlers. Places where lists are altered have to use irq safe > > spinlocks, which switch off interrupts while the lists are modified. > > > > All the other code can use readonly spinlocks. In any case you want to > > keep this locking as fine-grained as possible. > > > > Holger > > There's down_interruptible(demux->mutex), being called from > ioctl over several functions before it updates the list. > > OK, maybe this down_interruptible should be the spinlock. > > It will disable interrupts. Besides of disabling them, I think > it has to also wait for e.g. vpeirq() to finish. > > Is this wait_for_vpeirq() finish being done automatically > by the spinlock or should we after the spinlock additionaly > wait for vpeirq to finish ?
I think you might like to read the following documents: http://kernelnewbies.org/documents/kdoc/kernel-locking/lklockingguide.html http://lwn.net/Articles/21064/ HTH, Johannes -- Info: To unsubscribe send a mail to [EMAIL PROTECTED] with "unsubscribe linux-dvb" as subject.
