diff mbox series

[v6,17/18] arm64/mm: __always_inline to improve fork() perf

Message ID 20240215103205.2607016-18-ryan.roberts@arm.com (mailing list archive)
State New, archived
Headers show
Series Transparent Contiguous PTEs for User Mappings | expand

Commit Message

Ryan Roberts Feb. 15, 2024, 10:32 a.m. UTC 
As set_ptes() and wrprotect_ptes() become a bit more complex, the
compiler may choose not to inline them. But this is critical for fork()
performance. So mark the functions, along with contpte_try_unfold()
which is called by them, as __always_inline. This is worth ~1% on the
fork() microbenchmark with order-0 folios (the common case).

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
---
 arch/arm64/include/asm/pgtable.h | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Comments

Catalin Marinas Feb. 16, 2024, 12:34 p.m. UTC | #1 
On Thu, Feb 15, 2024 at 10:32:04AM +0000, Ryan Roberts wrote:
> As set_ptes() and wrprotect_ptes() become a bit more complex, the
> compiler may choose not to inline them. But this is critical for fork()
> performance. So mark the functions, along with contpte_try_unfold()
> which is called by them, as __always_inline. This is worth ~1% on the
> fork() microbenchmark with order-0 folios (the common case).
> 
> Acked-by: Mark Rutland <mark.rutland@arm.com>
> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index d759a20d2929..8310875133ff 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1206,8 +1206,8 @@  extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
 				unsigned long addr, pte_t *ptep,
 				pte_t entry, int dirty);
 
-static inline void contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
-					pte_t *ptep, pte_t pte)
+static __always_inline void contpte_try_unfold(struct mm_struct *mm,
+				unsigned long addr, pte_t *ptep, pte_t pte)
 {
 	if (unlikely(pte_valid_cont(pte)))
 		__contpte_try_unfold(mm, addr, ptep, pte);
@@ -1278,7 +1278,7 @@  static inline void set_pte(pte_t *ptep, pte_t pte)
 }
 
 #define set_ptes set_ptes
-static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
 				pte_t *ptep, pte_t pte, unsigned int nr)
 {
 	pte = pte_mknoncont(pte);
@@ -1360,8 +1360,8 @@  static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
 }
 
 #define wrprotect_ptes wrprotect_ptes
-static inline void wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
-				pte_t *ptep, unsigned int nr)
+static __always_inline void wrprotect_ptes(struct mm_struct *mm,
+				unsigned long addr, pte_t *ptep, unsigned int nr)
 {
 	if (likely(nr == 1)) {
 		/*