On Mon, 28 Jul 2008 20:05:14 +0200 John Ogness <[EMAIL PROTECTED]> wrote:
> On 2008-07-22, Frantisek Hrbata <[EMAIL PROTECTED]> wrote: > > generally it is a bad idea to use GFP_ATOMIC for all allocations > > like dazuko did. GFP_ATOMIC should be used only when it is really > > necessary, like in the irq where you can not block. With GFP_ATOMIC > > kernel has limited possibilities how to get memory(pages) for your > > allocation. So there is much bigger possibility that the allocation > > fails. > > I've been reworking the locking to avoid mallocs while having a > lock. In many places, this is not proving to be easy. > > But quite frankly, I was not aware that spinlocks were being used for > SMP. There is no reason that spinlocks are needed in *any* portion of > the Dazuko code. Dazuko uses locking primarily for inter-process > communication and very rarely for protecting critical sections. > > I need to see what kinds of locks I am *supposed* to be using. Any > tips would be greatly appreciated. (ie. what types of locks may be > held while performing GFP_KERNEL memory allocation?) Hi, you can use mutex(semaphore). It is safe to sleep while holding a mutex, because if other process can not acquire the mutex it is put to sleep and rescheduled in contrast to spinlock. -FH _______________________________________________ Dazuko-devel mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/dazuko-devel
