mm: split folio_pte_batch() into folio_pte_batch() and folio_pte_batch_flags()

Many users (including upcoming ones) don't really need the flags etc, and
can live with the possible overhead of a function call.

So let's provide a basic, non-inlined folio_pte_batch(), to avoid code
bloat while still providing a variant that optimizes out all flag checks
at runtime.  folio_pte_batch_flags() will get inlined into
folio_pte_batch(), optimizing out any conditionals that depend on input
flags.

folio_pte_batch() will behave like folio_pte_batch_flags() when no flags
are specified.  It's okay to add new users of folio_pte_batch_flags(), but
using folio_pte_batch() if applicable is preferred.

So, before this change, folio_pte_batch() was inlined into the C file
optimized by propagating constants within the resulting object file.

With this change, we now also have a folio_pte_batch() that is optimized
by propagating all constants.  But instead of having one instance per
object file, we have a single shared one.

In zap_present_ptes(), where we care about performance, the compiler
already seem to generate a call to a common inlined folio_pte_batch()
variant, shared with fork() code.  So calling the new non-inlined variant
should not make a difference.

While at it, drop the "addr" parameter that is unused.

Link: https://lkml.kernel.org/r/20250702104926.212243-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/linux-mm/20250503182858.5a02729fcffd6d4723afcfc2@linux-foundation.org/
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 3 insertions, 5 deletions

diff --git a/mm/memory.c b/mm/memory.c
index a03f1964db33..042088340b73 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -995,8 +995,8 @@ copy_present_ptes(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma
 		if (vma_soft_dirty_enabled(src_vma))
 			flags |= FPB_RESPECT_SOFT_DIRTY;
 
-		nr = folio_pte_batch(folio, addr, src_pte, pte, max_nr, flags,
-				     &any_writable, NULL, NULL);
+		nr = folio_pte_batch_flags(folio, src_pte, pte, max_nr, flags,
+					   &any_writable, NULL, NULL);
 		folio_ref_add(folio, nr);
 		if (folio_test_anon(folio)) {
 			if (unlikely(folio_try_dup_anon_rmap_ptes(folio, page,
@@ -1564,9 +1564,7 @@ static inline int zap_present_ptes(struct mmu_gather *tlb,
 	 * by keeping the batching logic separate.
 	 */
 	if (unlikely(folio_test_large(folio) && max_nr != 1)) {
-		nr = folio_pte_batch(folio, addr, pte, ptent, max_nr, 0,
-				     NULL, NULL, NULL);
-
+		nr = folio_pte_batch(folio, pte, ptent, max_nr);
 		zap_present_folio_ptes(tlb, vma, folio, page, pte, ptent, nr,
 				       addr, details, rss, force_flush,
 				       force_break, any_skipped);