On 18.07.2018 07:32, Martin Schwidefsky wrote:
> On Tue, 17 Jul 2018 21:43:03 +0200
> David Hildenbrand <david@xxxxxxxxxx> wrote:
>
>>> +/**
>>> + * gmap_pmdp_idte_global - invalidate and clear a guest pmd entry
>>> + * @mm: pointer to the process mm_struct
>>> + * @vmaddr: virtual address in the process address space
>>> + */
>>> +void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr)
>>> +{
>>> + unsigned long *entry, gaddr;
>>> + struct gmap *gmap;
>>> + pmd_t *pmdp;
>>> +
>>> + rcu_read_lock();
>>> + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
>>> + spin_lock(&gmap->guest_table_lock);
>>> + entry = radix_tree_delete(&gmap->host_to_guest,
>>> + vmaddr >> PMD_SHIFT);
>>> + if (entry) {
>>> + pmdp = (pmd_t *)entry;
>>> + gaddr = __gmap_segment_gaddr(entry);
>>> + pmdp_notify_gmap(gmap, pmdp, gaddr);
>>> + WARN_ON(*entry & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE |
>>> + _SEGMENT_ENTRY_GMAP_UC));
>>> + if (MACHINE_HAS_TLB_GUEST)
>>> + __pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE,
>>> + gmap->asce, IDTE_GLOBAL);
>>> + else if (MACHINE_HAS_IDTE)
>>> + __pmdp_idte(gaddr, pmdp, 0, 0, IDTE_GLOBAL);
>>> + else
>>> + __pmdp_csp(pmdp);
>>> + *entry = _SEGMENT_ENTRY_EMPTY;
>>> + }
>>> + spin_unlock(&gmap->guest_table_lock);
>>> + }
>>> + rcu_read_unlock();
>>> +}
>>> +EXPORT_SYMBOL_GPL(gmap_pmdp_idte_global);
>>
>> So you didn't like my suggestion of factoring out the common code of
>> gmap_pmdp_idte_local and gmap_pmdp_idte_global? They are almost
>> identical except of the IDTE flag.
>
> The local flag is passed to the inline assembly with [m4] "i" (local).
> The compiler has to pass in a *constant*, otherwise the compile will
> fail. If you factor out the code the flag is not a constant anymore, no?
>
If we pass IDTE_GLOBAL/IDTE_LOCAL to that new function and make it
always inline, that should work, no?
Produced code will be the same but only one code instance to maintain.
--
Thanks,
David / dhildenb
