search for: compound_order

...0700, Ralph Campbell wrote: > hmm_range_fault() returns an array of page frame numbers and flags for > how the pages are mapped in the requested process' page tables. The PFN > can be used to get the struct page with hmm_pfn_to_page() and the page size > order can be determined with compound_order(page) but if the page is larger > than order 0 (PAGE_SIZE), there is no indication that the page is mapped > using a larger page size. To be fully general, hmm_range_fault() would need > to return the mapping size to handle cases like a 1GB compound page being > mapped with 2MB PMD entr...

...t; hmm_range_fault() returns an array of page frame numbers and flags for > > > how the pages are mapped in the requested process' page tables. The PFN > > > can be used to get the struct page with hmm_pfn_to_page() and the page size > > > order can be determined with compound_order(page) but if the page is larger > > > than order 0 (PAGE_SIZE), there is no indication that the page is mapped > > > using a larger page size. To be fully general, hmm_range_fault() would need > > > to return the mapping size to handle cases like a 1GB compound page being...

...bell wrote: >> hmm_range_fault() returns an array of page frame numbers and flags for >> how the pages are mapped in the requested process' page tables. The PFN >> can be used to get the struct page with hmm_pfn_to_page() and the page size >> order can be determined with compound_order(page) but if the page is larger >> than order 0 (PAGE_SIZE), there is no indication that the page is mapped >> using a larger page size. To be fully general, hmm_range_fault() would need >> to return the mapping size to handle cases like a 1GB compound page being >> mapped w...

...f whatever page size) in a single chunk. And > > we support arbitrary power of two page sizes. I suggest something like this: > > > > u64 page_to_chunk(struct page *page) > > { > > u64 chunk = page_to_pfn(page) << PAGE_SHIFT; > > chunk |= (1UL << compound_order(page)) - 1; > > } > > You need to fill in the size, do you not? I think I did ... (1UL << compound_order(page)) - 1 sets the bottom N bits. Bit N+1 will already be clear. What am I missing? > > > - host should pass its base page size to guest > > > this ca...

...f whatever page size) in a single chunk. And > > we support arbitrary power of two page sizes. I suggest something like this: > > > > u64 page_to_chunk(struct page *page) > > { > > u64 chunk = page_to_pfn(page) << PAGE_SHIFT; > > chunk |= (1UL << compound_order(page)) - 1; > > } > > You need to fill in the size, do you not? I think I did ... (1UL << compound_order(page)) - 1 sets the bottom N bits. Bit N+1 will already be clear. What am I missing? > > > - host should pass its base page size to guest > > > this ca...

...to create device private > transparent huge pages. This is intended to help support device private > THP migrations. I think you'd be better off with these calling conventions: -void prep_transhuge_page(struct page *page) +struct page *thp_prep(struct page *page) { + if (!page || compound_order(page) == 0) + return page; /* - * we use page->mapping and page->indexlru in second tail page + * we use page->mapping and page->index in second tail page * as list_head: assuming THP order >= 2 */ + BUG_ON(compound_order(pa...

...if (ppage) { - *ppage = mdevice->free_pages; - mdevice->free_pages = (*ppage)->zone_device_data; - mdevice->calloc++; + if (is_huge) { + *ppage = mdevice->free_huge_pages; + mdevice->free_huge_pages = (*ppage)->zone_device_data; + mdevice->calloc += 1UL << compound_order(*ppage); + } else { + *ppage = mdevice->free_pages; + mdevice->free_pages = (*ppage)->zone_device_data; + mdevice->calloc++; + } } spin_unlock(&mdevice->lock); @@ -527,7 +552,8 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, return false; }...

...gle chunk. And > > > we support arbitrary power of two page sizes. I suggest something like this: > > > > > > u64 page_to_chunk(struct page *page) > > > { > > > u64 chunk = page_to_pfn(page) << PAGE_SHIFT; > > > chunk |= (1UL << compound_order(page)) - 1; > > > } > > > > You need to fill in the size, do you not? > > I think I did ... (1UL << compound_order(page)) - 1 sets the bottom > N bits. Bit N+1 will already be clear. What am I missing? This sets the order but not the number of pages. For tha...

...0700, Ralph Campbell wrote: > hmm_range_fault() returns an array of page frame numbers and flags for > how the pages are mapped in the requested process' page tables. The PFN > can be used to get the struct page with hmm_pfn_to_page() and the page size > order can be determined with compound_order(page) but if the page is larger > than order 0 (PAGE_SIZE), there is no indication that the page is mapped > using a larger page size. To be fully general, hmm_range_fault() would need > to return the mapping size to handle cases like a 1GB compound page being > mapped with 2MB PMD entr...

..., page size 64k That means we can always pass 2048 pages (of whatever page size) in a single chunk. And we support arbitrary power of two page sizes. I suggest something like this: u64 page_to_chunk(struct page *page) { u64 chunk = page_to_pfn(page) << PAGE_SHIFT; chunk |= (1UL << compound_order(page)) - 1; } (note this is a single page of order N, so we leave the page count bits set to 0, meaning one page). > Two things to consider: > - host should pass its base page size to guest > this can be a separate patch and for now we can fall back on 12 bit if not there With this en...

...bell wrote: >> hmm_range_fault() returns an array of page frame numbers and flags for >> how the pages are mapped in the requested process' page tables. The PFN >> can be used to get the struct page with hmm_pfn_to_page() and the page size >> order can be determined with compound_order(page) but if the page is larger >> than order 0 (PAGE_SIZE), there is no indication that the page is mapped >> using a larger page size. To be fully general, hmm_range_fault() would need >> to return the mapping size to handle cases like a 1GB compound page being >> mapped w...

On Fri, Mar 10, 2017 at 07:37:28PM +0800, Wei Wang wrote: > On 03/09/2017 10:14 PM, Matthew Wilcox wrote: > > On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > > > From: Liang Li <liang.z.li at intel.com> > > > 1) allocating pages (6.5%) > > > 2) sending PFNs to host (68.3%) > > > 3) address translation (6.1%) > > > 4) madvise

On Fri, Mar 10, 2017 at 07:37:28PM +0800, Wei Wang wrote: > On 03/09/2017 10:14 PM, Matthew Wilcox wrote: > > On Fri, Mar 03, 2017 at 01:40:28PM +0800, Wei Wang wrote: > > > From: Liang Li <liang.z.li at intel.com> > > > 1) allocating pages (6.5%) > > > 2) sending PFNs to host (68.3%) > > > 3) address translation (6.1%) > > > 4) madvise

...0700, Ralph Campbell wrote: > hmm_range_fault() returns an array of page frame numbers and flags for > how the pages are mapped in the requested process' page tables. The PFN > can be used to get the struct page with hmm_pfn_to_page() and the page > size order can be determined with compound_order(page) but if the page > is larger than order 0 (PAGE_SIZE), there is no indication that a > compound page is mapped by the CPU using a larger page size. Without > this information, the caller can't safely use a large device PTE to map > the compound page because the CPU might be usi...

...bell wrote: >> hmm_range_fault() returns an array of page frame numbers and flags for >> how the pages are mapped in the requested process' page tables. The PFN >> can be used to get the struct page with hmm_pfn_to_page() and the page size >> order can be determined with compound_order(page) but if the page is larger >> than order 0 (PAGE_SIZE), there is no indication that the page is mapped >> using a larger page size. To be fully general, hmm_range_fault() would need >> to return the mapping size to handle cases like a 1GB compound page being >> mapped w...

...>> hmm_range_fault() returns an array of page frame numbers and flags for >>> how the pages are mapped in the requested process' page tables. The PFN >>> can be used to get the struct page with hmm_pfn_to_page() and the page size >>> order can be determined with compound_order(page) but if the page is larger >>> than order 0 (PAGE_SIZE), there is no indication that the page is mapped >>> using a larger page size. To be fully general, hmm_range_fault() would need >>> to return the mapping size to handle cases like a 1GB compound page being >&...

These patches apply to linux-5.8.0-rc1. Patches 1-3 should probably go into 5.8, the others can be queued for 5.9. Patches 4-6 improve the HMM self tests. Patch 7-8 prepare nouveau for the meat of this series which adds support and testing for compound page mapping of system memory (patches 9-11) and compound page migration to device private memory (patches 12-16). Since these changes are split

hmm_range_fault() returns an array of page frame numbers and flags for how the pages are mapped in the requested process' page tables. The PFN can be used to get the struct page with hmm_pfn_to_page() and the page size order can be determined with compound_order(page) but if the page is larger than order 0 (PAGE_SIZE), there is no indication that the page is mapped using a larger page size. To be fully general, hmm_range_fault() would need to return the mapping size to handle cases like a 1GB compound page being mapped with 2MB PMD entries. However, the mo...

hmm_range_fault() returns an array of page frame numbers and flags for how the pages are mapped in the requested process' page tables. The PFN can be used to get the struct page with hmm_pfn_to_page() and the page size order can be determined with compound_order(page) but if the page is larger than order 0 (PAGE_SIZE), there is no indication that the page is mapped using a larger page size. To be fully general, hmm_range_fault() would need to return the mapping size to handle cases like a 1GB compound page being mapped with 2MB PMD entries. However, the mo...

...0700, Ralph Campbell wrote: > hmm_range_fault() returns an array of page frame numbers and flags for > how the pages are mapped in the requested process' page tables. The PFN > can be used to get the struct page with hmm_pfn_to_page() and the page size > order can be determined with compound_order(page) but if the page is larger > than order 0 (PAGE_SIZE), there is no indication that the page is mapped > using a larger page size. To be fully general, hmm_range_fault() would need > to return the mapping size to handle cases like a 1GB compound page being > mapped with 2MB PMD entr...