On 11/19/2012 03:10 PM, Maarten Lankhorst wrote: > Op 19-11-12 14:33, Thomas Hellstrom schreef: >> On 11/12/2012 03:00 PM, Maarten Lankhorst wrote: >>> Just use the return error from ttm_mem_evict_first instead. >> Here driver need to be able to evict a memory type completely, because they >> might shut down >> the memory type or clear it for some legacy usage, suspending or whatever, >> so returning 0 on -EBUSY isn't sufficient, >> we need at least a list empty check, and a shared reservation at this point >> is illegal. >> >> This is a point where the mechanism to exclude other reservers is needed, as >> we discussed previously. >> vmwgfx is using the ttm lock, but will of course adapt if a new mechanism is >> emerging. > Normally ttm_mem_evict_first only returns -EBUSY if the list is empty and > no_wait = false, > so I thought using the return code would be equivalent. > > We could do spin_lock(&glob->lru_lock); WARN_ON(!list_empty(&man->lru_lock)); > spin_unlock(&glob->lru_lock); to handle this after -EBUSY. > > With a lot of objects on the lru list, this would save taking lru_lock twice > for each object. > > ~Maarten
Sure, and in the allow_errors case we should return an error if the list isn't empty, to allow careful drivers to deal with that. /Thomas > > _______________________________________________ > dri-devel mailing list > dri-devel at lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel
