The quilt patch titled Subject: mm: shmem: fix the shmem large folio allocation for the i915 driver has been removed from the -mm tree. Its filename was mm-shmem-fix-the-shmem-large-folio-allocation-for-the-i915-driver.patch

This patch was dropped because an alternative patch was or shall be merged

------------------------------------------------------ From: Baolin Wang baolin.wang@linux.alibaba.com Subject: mm: shmem: fix the shmem large folio allocation for the i915 driver Date: Mon, 28 Jul 2025 16:03:53 +0800

After commit acd7ccb284b8 ("mm: shmem: add large folio support for tmpfs"), we extend the 'huge=' option to allow any sized large folios for tmpfs, which means tmpfs will allow getting a highest order hint based on the size of write() and fallocate() paths, and then will try each allowable large order.

However, when the i915 driver allocates shmem memory, it doesn't provide hint information about the size of the large folio to be allocated, resulting in the inability to allocate PMD-sized shmem, which in turn affects GPU performance.

To fix this issue, add the 'end' information for shmem_read_folio_gfp() to help allocate PMD-sized large folios. Additionally, use the maximum allocation chunk (via mapping_max_folio_size()) to determine the size of the large folios to allocate in the i915 driver.

Patryk added:

: In my tests, the performance drop ranges from a few percent up to 13% : in Unigine Superposition under heavy memory usage on the CPU Core Ultra : 155H with the Xe 128 EU GPU. Other users have reported performance : impact up to 30% on certain workloads. Please find more in the : regressions reports: : https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14645 : https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13845 : : I believe the change should be backported to all active kernel branches : after version 6.12.

Link: https://lkml.kernel.org/r/0d734549d5ed073c80b11601da3abdd5223e1889.175368980... Fixes: acd7ccb284b8 ("mm: shmem: add large folio support for tmpfs") Signed-off-by: Baolin Wang baolin.wang@linux.alibaba.com Reported-by: Patryk Kowalczyk patryk@kowalczyk.ws Reported-by: Ville Syrj��l�� ville.syrjala@linux.intel.com Tested-by: Patryk Kowalczyk patryk@kowalczyk.ws Cc: Christan K��nig christian.koenig@amd.com Cc: Dave Airlie airlied@gmail.com Cc: David Hildenbrand david@redhat.com Cc: Huang Ray Ray.Huang@amd.com Cc: Hugh Dickins hughd@google.com Cc: Jani Nikula jani.nikula@linux.intel.com Cc: Jonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Mathew Brost matthew.brost@intel.com Cc: Matthew Auld matthew.auld@intel.com Cc: Matthew Wilcox (Oracle) willy@infradead.org Cc: Maxime Ripard mripard@kernel.org Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Thomas Zimemrmann tzimmermann@suse.de Cc: Tvrtko Ursulin tursulin@ursulin.net Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

drivers/gpu/drm/drm_gem.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 7 ++++++- drivers/gpu/drm/ttm/ttm_backup.c | 2 +- include/linux/shmem_fs.h | 4 ++-- mm/shmem.c | 7 ++++--- 5 files changed, 14 insertions(+), 8 deletions(-)

--- a/drivers/gpu/drm/drm_gem.c~mm-shmem-fix-the-shmem-large-folio-allocation-for-the-i915-driver +++ a/drivers/gpu/drm/drm_gem.c @@ -627,7 +627,7 @@ struct page **drm_gem_get_pages(struct d i = 0; while (i < npages) { long nr; - folio = shmem_read_folio_gfp(mapping, i, + folio = shmem_read_folio_gfp(mapping, i, 0, mapping_gfp_mask(mapping)); if (IS_ERR(folio)) goto fail; --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c~mm-shmem-fix-the-shmem-large-folio-allocation-for-the-i915-driver +++ a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c @@ -69,6 +69,7 @@ int shmem_sg_alloc_table(struct drm_i915 struct scatterlist *sg; unsigned long next_pfn = 0; /* suppress gcc warning */ gfp_t noreclaim; + size_t chunk; int ret;

if (overflows_type(size / PAGE_SIZE, page_count)) @@ -94,6 +95,7 @@ int shmem_sg_alloc_table(struct drm_i915 mapping_set_unevictable(mapping); noreclaim = mapping_gfp_constraint(mapping, ~__GFP_RECLAIM); noreclaim |= __GFP_NORETRY | __GFP_NOWARN; + chunk = mapping_max_folio_size(mapping);

sg = st->sgl; st->nents = 0; @@ -105,10 +107,13 @@ int shmem_sg_alloc_table(struct drm_i915 0, }, *s = shrink; gfp_t gfp = noreclaim; + loff_t bytes = (page_count - i) << PAGE_SHIFT; + loff_t pos = i << PAGE_SHIFT;

+ bytes = min_t(loff_t, chunk, bytes); do { cond_resched(); - folio = shmem_read_folio_gfp(mapping, i, gfp); + folio = shmem_read_folio_gfp(mapping, i, pos + bytes, gfp); if (!IS_ERR(folio)) break;

--- a/drivers/gpu/drm/ttm/ttm_backup.c~mm-shmem-fix-the-shmem-large-folio-allocation-for-the-i915-driver +++ a/drivers/gpu/drm/ttm/ttm_backup.c @@ -100,7 +100,7 @@ ttm_backup_backup_page(struct file *back struct folio *to_folio; int ret;

- to_folio = shmem_read_folio_gfp(mapping, idx, alloc_gfp); + to_folio = shmem_read_folio_gfp(mapping, idx, 0, alloc_gfp); if (IS_ERR(to_folio)) return PTR_ERR(to_folio);

--- a/include/linux/shmem_fs.h~mm-shmem-fix-the-shmem-large-folio-allocation-for-the-i915-driver +++ a/include/linux/shmem_fs.h @@ -153,12 +153,12 @@ enum sgp_type { int shmem_get_folio(struct inode *inode, pgoff_t index, loff_t write_end, struct folio **foliop, enum sgp_type sgp); struct folio *shmem_read_folio_gfp(struct address_space *mapping, - pgoff_t index, gfp_t gfp); + pgoff_t index, loff_t end, gfp_t gfp);

static inline struct folio *shmem_read_folio(struct address_space *mapping, pgoff_t index) { - return shmem_read_folio_gfp(mapping, index, mapping_gfp_mask(mapping)); + return shmem_read_folio_gfp(mapping, index, 0, mapping_gfp_mask(mapping)); }

static inline struct page *shmem_read_mapping_page( --- a/mm/shmem.c~mm-shmem-fix-the-shmem-large-folio-allocation-for-the-i915-driver +++ a/mm/shmem.c @@ -5930,6 +5930,7 @@ int shmem_zero_setup(struct vm_area_stru * shmem_read_folio_gfp - read into page cache, using specified page allocation flags. * @mapping: the folio's address_space * @index: the folio index + * @end: end of a read if allocating a new folio * @gfp: the page allocator flags to use if allocating * * This behaves as a tmpfs "read_cache_page_gfp(mapping, index, gfp)", @@ -5942,14 +5943,14 @@ int shmem_zero_setup(struct vm_area_stru * with the mapping_gfp_mask(), to avoid OOMing the machine unnecessarily. */ struct folio *shmem_read_folio_gfp(struct address_space *mapping, - pgoff_t index, gfp_t gfp) + pgoff_t index, loff_t end, gfp_t gfp) { #ifdef CONFIG_SHMEM struct inode *inode = mapping->host; struct folio *folio; int error;

- error = shmem_get_folio_gfp(inode, index, 0, &folio, SGP_CACHE, + error = shmem_get_folio_gfp(inode, index, end, &folio, SGP_CACHE, gfp, NULL, NULL); if (error) return ERR_PTR(error); @@ -5968,7 +5969,7 @@ EXPORT_SYMBOL_GPL(shmem_read_folio_gfp); struct page *shmem_read_mapping_page_gfp(struct address_space *mapping, pgoff_t index, gfp_t gfp) { - struct folio *folio = shmem_read_folio_gfp(mapping, index, gfp); + struct folio *folio = shmem_read_folio_gfp(mapping, index, 0, gfp); struct page *page;

if (IS_ERR(folio)) _

Patches currently in -mm which might be from baolin.wang@linux.alibaba.com are