powerpc/mm/book(e)(3s)/64: Add page table accounting
Introduce a helper pgtable_gfp_flags() which
just returns the current gfp flags and adds
__GFP_ACCOUNT to account for page table allocation.
The generic helper is added to include/asm/pgalloc.h
and has two variants - WARNING ugly bits ahead
1. If the header is included from a module, no check
for mm == &init_mm is done, since init_mm is not
exported
2. For kernel includes, the check is done and required
see (3e79ec7 arch: x86: charge page tables to kmemcg)
The fundamental assumption is that no module should be
doing pgd/pud/pmd and pte alloc's on behalf of init_mm
directly.
NOTE: This adds an overhead to pmd/pud/pgd allocations
similar to x86. The other alternative was to implement
pmd_alloc_kernel/pud_alloc_kernel and pgd_alloc_kernel
with their offset variants.
For 4k page size, pte_alloc_one no longer calls
pte_alloc_one_kernel.
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/include/asm/pgalloc.h b/arch/powerpc/include/asm/pgalloc.h
index 0413457..d795c5d 100644
--- a/arch/powerpc/include/asm/pgalloc.h
+++ b/arch/powerpc/include/asm/pgalloc.h
@@ -3,6 +3,20 @@
#include <linux/mm.h>
+#ifndef MODULE
+static inline gfp_t pgtable_gfp_flags(struct mm_struct *mm, gfp_t gfp)
+{
+ if (unlikely(mm == &init_mm))
+ return gfp;
+ return gfp | __GFP_ACCOUNT;
+}
+#else /* !MODULE */
+static inline gfp_t pgtable_gfp_flags(struct mm_struct *mm, gfp_t gfp)
+{
+ return gfp | __GFP_ACCOUNT;
+}
+#endif /* MODULE */
+
#ifdef CONFIG_PPC_BOOK3S
#include <asm/book3s/pgalloc.h>
#else