On Wed, 31 Mar 2010, Matthew Wilcox wrote: > On Wed, Mar 31, 2010 at 02:05:00PM -0700, H. Peter Anvin wrote: > > What I note is that lib/rwsem-spinlock.c seems to be rather inconsistent > > in its use of spin_lock_irqsave/spin_lock_irqrestore versus > > spin_lock_irq/spin_unlock_irq... in fact, __down_read is the *only* > > place where we use the latter as opposed to the former. > > > > Is that a bug? If so, it would certainly explain this behavior. > > It's based on down_read() and down_write() not being callable from > interrupt context, or with interrupts disabled (since they can sleep). > up_read(), up_write(), down_read_trylock(), down_write_trylock(), > downgrade_write() can all be called from interrupt context since they > cannot sleep. Do not run the checks while we are in a single threaded context? I thought we had some dynamic code patching thingamy that could change those when we go to smp mode? -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
