Re: [PATCH] gnumach: vm: zone_gc: Got rid of useless function

[Richard Braun]

On Mon, Apr 18, 2011 at 10:05:57PM +0200, Samuel Thibault wrote:
> I don't think this patch can be applied. Building a list and then
> freeing it was done for some reason, at least because kmem_free, (thus
> vm_map_delete), may actually need to use zalloc in order to split
> some areas (which is actually the reason for the double map_entry
> allocation/release), which thus needs to lock the zone, and thus ends up
> with a deadlock.

This change seems rather dangerous. It brings no real improvement while
adding a potential deadlock.

In addition to avoiding deadlocks, freeing list elements in two steps
is also a technique commonly used to reduce contention.

-- 
Richard Braun