Hi, Christopher I got one confusion on understanding one case in __slab_free(). The case is : (new.frozen && !was_frozen) My confusion is : Is it possible for the page to be on the full list? This case (new.frozen && !was_frozen) happens when (!prior && !was_frozen). * !prior means this page is full * !was_frozen means this page is not in cpu_slab->page/partial There are two cases to lead to (!prior && !was_frozen): * in get_freelist(), when page is full * in deactivate_slab(), when page is full The first case will have a page in no list. The second case will have a page in no list, or the page is put into full list if SLUB_DEBUG is configured. Do I miss something? On Thu, Oct 25, 2018 at 01:46:49PM +0000, Christopher Lameter wrote: >On Thu, 25 Oct 2018, Wei Yang wrote: > >> In current code, the following context always meets: >> >> local_irq_save/disable() >> ___slab_alloc() >> new_slab_objects() >> local_irq_restore/enable() >> >> This context ensures cpu will continue running until it finish this job >> before yield its control, which means the cpu_slab retrieved in >> new_slab_objects() is the same as passed in. > >Interrupts can be switched on in new_slab() since it goes to the page >allocator. See allocate_slab(). > >This means that the percpu slab may change. -- Wei Yang Help you, Help me
