On Tue, Nov 24, 2020 at 09:17:38AM +0000, Christoph Hellwig wrote:
> > @@ -470,6 +487,26 @@ void ocxl_link_release(struct pci_dev *dev, void
> > *link_handle)
> > }
> > EXPORT_SYMBOL_GPL(ocxl_link_release);
> >
> > +static void invalidate_range(struct mmu_notifier *mn,
> > + struct mm_struct *mm,
> > + unsigned long start, unsigned long end)
> > +{
> > + struct pe_data *pe_data = container_of(mn, struct pe_data,
> > mmu_notifier);
> > + struct ocxl_link *link = pe_data->link;
> > + unsigned long addr, pid, page_size = PAGE_SIZE;
The page_size variable seems unnecessary
> > +
> > + pid = mm->context.id;
> > +
> > + spin_lock(&link->atsd_lock);
> > + for (addr = start; addr < end; addr += page_size)
> > + pnv_ocxl_tlb_invalidate(&link->arva, pid, addr);
> > + spin_unlock(&link->atsd_lock);
> > +}
> > +
> > +static const struct mmu_notifier_ops ocxl_mmu_notifier_ops = {
> > + .invalidate_range = invalidate_range,
> > +};
> > +
> > static u64 calculate_cfg_state(bool kernel)
> > {
> > u64 state;
> > @@ -526,6 +563,8 @@ int ocxl_link_add_pe(void *link_handle, int pasid, u32
> > pidr, u32 tidr,
> > pe_data->mm = mm;
> > pe_data->xsl_err_cb = xsl_err_cb;
> > pe_data->xsl_err_data = xsl_err_data;
> > + pe_data->link = link;
> > + pe_data->mmu_notifier.ops = &ocxl_mmu_notifier_ops;
> >
> > memset(pe, 0, sizeof(struct ocxl_process_element));
> > pe->config_state = cpu_to_be64(calculate_cfg_state(pidr == 0));
> > @@ -542,8 +581,16 @@ int ocxl_link_add_pe(void *link_handle, int pasid, u32
> > pidr, u32 tidr,
> > * by the nest MMU. If we have a kernel context, TLBIs are
> > * already global.
> > */
> > - if (mm)
> > + if (mm) {
> > mm_context_add_copro(mm);
> > + if (link->arva) {
> > + /* Use MMIO registers for the TLB Invalidate
> > + * operations.
> > + */
> > + mmu_notifier_register(&pe_data->mmu_notifier, mm);
Every other place doing stuff like this is de-duplicating the
notifier. If you have multiple clients this will do multiple redundant
invalidations?
The notifier get/put API is designed to solve that problem, you'd get
a single notifier for the mm and then add the impacted arva's to some
list at the notifier.
Jason
