All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jisheng Zhang <jszhang@kernel.org>
To: Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	Alexandre Ghiti <alexandre.ghiti@canonical.com>,
	Anup Patel <anup@brainfault.org>,
	Atish Patra <atishp@rivosinc.com>
Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	kasan-dev@googlegroups.com
Subject: [PATCH v4 2/2] riscv: turn pgtable_l4|[l5]_enabled to static key for RV64
Date: Sat, 21 May 2022 22:34:56 +0800	[thread overview]
Message-ID: <20220521143456.2759-3-jszhang@kernel.org> (raw)
In-Reply-To: <20220521143456.2759-1-jszhang@kernel.org>

On a specific HW platform, pgtable_l4|[l5]_enabled won't change after
boot, and the check sits at hot code path, this characteristic makes it
suitable for optimization with static key.

_pgtable_l4|[l5]_enabled is used very early during boot, even is used
with MMU off, so the static key mechanism isn't ready. For this case,
we use another static key _pgtable_lx_ready to indicate whether we
have finalised pgtable_l4|[l5]_enabled or not, then fall back to
_pgtable_l4|[l5]_enabled_early bool.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
 arch/riscv/include/asm/pgalloc.h    | 16 ++++----
 arch/riscv/include/asm/pgtable-32.h |  3 ++
 arch/riscv/include/asm/pgtable-64.h | 60 ++++++++++++++++++---------
 arch/riscv/include/asm/pgtable.h    |  5 +--
 arch/riscv/kernel/cpu.c             |  4 +-
 arch/riscv/mm/init.c                | 64 ++++++++++++++++++-----------
 arch/riscv/mm/kasan_init.c          | 16 ++++----
 7 files changed, 103 insertions(+), 65 deletions(-)

diff --git a/arch/riscv/include/asm/pgalloc.h b/arch/riscv/include/asm/pgalloc.h
index 947f23d7b6af..0280eeb4756f 100644
--- a/arch/riscv/include/asm/pgalloc.h
+++ b/arch/riscv/include/asm/pgalloc.h
@@ -41,7 +41,7 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 
 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 {
-	if (pgtable_l4_enabled) {
+	if (pgtable_l4_enabled()) {
 		unsigned long pfn = virt_to_pfn(pud);
 
 		set_p4d(p4d, __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
@@ -51,7 +51,7 @@ static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d,
 				     pud_t *pud)
 {
-	if (pgtable_l4_enabled) {
+	if (pgtable_l4_enabled()) {
 		unsigned long pfn = virt_to_pfn(pud);
 
 		set_p4d_safe(p4d,
@@ -61,7 +61,7 @@ static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d,
 
 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 {
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		unsigned long pfn = virt_to_pfn(p4d);
 
 		set_pgd(pgd, __pgd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
@@ -71,7 +71,7 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd,
 				     p4d_t *p4d)
 {
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		unsigned long pfn = virt_to_pfn(p4d);
 
 		set_pgd_safe(pgd,
@@ -82,7 +82,7 @@ static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd,
 #define pud_alloc_one pud_alloc_one
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return __pud_alloc_one(mm, addr);
 
 	return NULL;
@@ -91,7 +91,7 @@ static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 #define pud_free pud_free
 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		__pud_free(mm, pud);
 }
 
@@ -100,7 +100,7 @@ static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 #define p4d_alloc_one p4d_alloc_one
 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		gfp_t gfp = GFP_PGTABLE_USER;
 
 		if (mm == &init_mm)
@@ -120,7 +120,7 @@ static inline void __p4d_free(struct mm_struct *mm, p4d_t *p4d)
 #define p4d_free p4d_free
 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		__p4d_free(mm, p4d);
 }
 
diff --git a/arch/riscv/include/asm/pgtable-32.h b/arch/riscv/include/asm/pgtable-32.h
index 5b2e79e5bfa5..8af36d76b70d 100644
--- a/arch/riscv/include/asm/pgtable-32.h
+++ b/arch/riscv/include/asm/pgtable-32.h
@@ -16,4 +16,7 @@
 
 #define MAX_POSSIBLE_PHYSMEM_BITS 34
 
+#define pgtable_l5_enabled() 0
+#define pgtable_l4_enabled() 0
+
 #endif /* _ASM_RISCV_PGTABLE_32_H */
diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
index 7e246e9f8d70..d14a3a8f1f4b 100644
--- a/arch/riscv/include/asm/pgtable-64.h
+++ b/arch/riscv/include/asm/pgtable-64.h
@@ -7,17 +7,37 @@
 #define _ASM_RISCV_PGTABLE_64_H
 
 #include <linux/const.h>
+#include <linux/jump_label.h>
 
-extern bool pgtable_l4_enabled;
-extern bool pgtable_l5_enabled;
+extern bool _pgtable_l5_enabled_early;
+extern bool _pgtable_l4_enabled_early;
+extern struct static_key_false _pgtable_l5_enabled;
+extern struct static_key_false _pgtable_l4_enabled;
+extern struct static_key_false _pgtable_lx_ready;
+
+static __always_inline bool pgtable_l5_enabled(void)
+{
+	if (static_branch_likely(&_pgtable_lx_ready))
+		return static_branch_likely(&_pgtable_l5_enabled);
+	else
+		return _pgtable_l5_enabled_early;
+}
+
+static __always_inline bool pgtable_l4_enabled(void)
+{
+	if (static_branch_likely(&_pgtable_lx_ready))
+		return static_branch_likely(&_pgtable_l4_enabled);
+	else
+		return _pgtable_l4_enabled_early;
+}
 
 #define PGDIR_SHIFT_L3  30
 #define PGDIR_SHIFT_L4  39
 #define PGDIR_SHIFT_L5  48
 #define PGDIR_SIZE_L3   (_AC(1, UL) << PGDIR_SHIFT_L3)
 
-#define PGDIR_SHIFT     (pgtable_l5_enabled ? PGDIR_SHIFT_L5 : \
-		(pgtable_l4_enabled ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3))
+#define PGDIR_SHIFT     (pgtable_l5_enabled() ? PGDIR_SHIFT_L5 : \
+		(pgtable_l4_enabled() ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3))
 /* Size of region mapped by a page global directory */
 #define PGDIR_SIZE      (_AC(1, UL) << PGDIR_SHIFT)
 #define PGDIR_MASK      (~(PGDIR_SIZE - 1))
@@ -119,7 +139,7 @@ static inline struct page *pud_page(pud_t pud)
 #define mm_p4d_folded  mm_p4d_folded
 static inline bool mm_p4d_folded(struct mm_struct *mm)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return false;
 
 	return true;
@@ -128,7 +148,7 @@ static inline bool mm_p4d_folded(struct mm_struct *mm)
 #define mm_pud_folded  mm_pud_folded
 static inline bool mm_pud_folded(struct mm_struct *mm)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return false;
 
 	return true;
@@ -159,7 +179,7 @@ static inline unsigned long _pmd_pfn(pmd_t pmd)
 
 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		*p4dp = p4d;
 	else
 		set_pud((pud_t *)p4dp, (pud_t){ p4d_val(p4d) });
@@ -167,7 +187,7 @@ static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
 
 static inline int p4d_none(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return (p4d_val(p4d) == 0);
 
 	return 0;
@@ -175,7 +195,7 @@ static inline int p4d_none(p4d_t p4d)
 
 static inline int p4d_present(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return (p4d_val(p4d) & _PAGE_PRESENT);
 
 	return 1;
@@ -183,7 +203,7 @@ static inline int p4d_present(p4d_t p4d)
 
 static inline int p4d_bad(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return !p4d_present(p4d);
 
 	return 0;
@@ -191,7 +211,7 @@ static inline int p4d_bad(p4d_t p4d)
 
 static inline void p4d_clear(p4d_t *p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		set_p4d(p4d, __p4d(0));
 }
 
@@ -207,7 +227,7 @@ static inline unsigned long _p4d_pfn(p4d_t p4d)
 
 static inline pud_t *p4d_pgtable(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return (pud_t *)pfn_to_virt(p4d_val(p4d) >> _PAGE_PFN_SHIFT);
 
 	return (pud_t *)pud_pgtable((pud_t) { p4d_val(p4d) });
@@ -224,7 +244,7 @@ static inline struct page *p4d_page(p4d_t p4d)
 #define pud_offset pud_offset
 static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return p4d_pgtable(*p4d) + pud_index(address);
 
 	return (pud_t *)p4d;
@@ -232,7 +252,7 @@ static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
 
 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		*pgdp = pgd;
 	else
 		set_p4d((p4d_t *)pgdp, (p4d_t){ pgd_val(pgd) });
@@ -240,7 +260,7 @@ static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 
 static inline int pgd_none(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return (pgd_val(pgd) == 0);
 
 	return 0;
@@ -248,7 +268,7 @@ static inline int pgd_none(pgd_t pgd)
 
 static inline int pgd_present(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return (pgd_val(pgd) & _PAGE_PRESENT);
 
 	return 1;
@@ -256,7 +276,7 @@ static inline int pgd_present(pgd_t pgd)
 
 static inline int pgd_bad(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return !pgd_present(pgd);
 
 	return 0;
@@ -264,13 +284,13 @@ static inline int pgd_bad(pgd_t pgd)
 
 static inline void pgd_clear(pgd_t *pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		set_pgd(pgd, __pgd(0));
 }
 
 static inline p4d_t *pgd_pgtable(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return (p4d_t *)pfn_to_virt(pgd_val(pgd) >> _PAGE_PFN_SHIFT);
 
 	return (p4d_t *)p4d_pgtable((p4d_t) { pgd_val(pgd) });
@@ -288,7 +308,7 @@ static inline struct page *pgd_page(pgd_t pgd)
 #define p4d_offset p4d_offset
 static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return pgd_pgtable(*pgd) + p4d_index(address);
 
 	return (p4d_t *)pgd;
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 046b44225623..ae01a9b83ac4 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -63,8 +63,8 @@
  * position vmemmap directly below the VMALLOC region.
  */
 #ifdef CONFIG_64BIT
-#define VA_BITS		(pgtable_l5_enabled ? \
-				57 : (pgtable_l4_enabled ? 48 : 39))
+#define VA_BITS		(pgtable_l5_enabled() ? \
+				57 : (pgtable_l4_enabled() ? 48 : 39))
 #else
 #define VA_BITS		32
 #endif
@@ -738,7 +738,6 @@ extern uintptr_t _dtb_early_pa;
 #define dtb_early_pa	_dtb_early_pa
 #endif /* CONFIG_XIP_KERNEL */
 extern u64 satp_mode;
-extern bool pgtable_l4_enabled;
 
 void paging_init(void);
 void misc_mem_init(void);
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index ccb617791e56..29bb0ef75248 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -141,9 +141,9 @@ static void print_mmu(struct seq_file *f)
 #if defined(CONFIG_32BIT)
 	strncpy(sv_type, "sv32", 5);
 #elif defined(CONFIG_64BIT)
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		strncpy(sv_type, "sv57", 5);
-	else if (pgtable_l4_enabled)
+	else if (pgtable_l4_enabled())
 		strncpy(sv_type, "sv48", 5);
 	else
 		strncpy(sv_type, "sv39", 5);
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 05ed641a1134..42c79388e6fd 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -44,10 +44,16 @@ u64 satp_mode __ro_after_init = SATP_MODE_32;
 #endif
 EXPORT_SYMBOL(satp_mode);
 
-bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
-bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
-EXPORT_SYMBOL(pgtable_l4_enabled);
-EXPORT_SYMBOL(pgtable_l5_enabled);
+DEFINE_STATIC_KEY_FALSE(_pgtable_l4_enabled);
+DEFINE_STATIC_KEY_FALSE(_pgtable_l5_enabled);
+DEFINE_STATIC_KEY_FALSE(_pgtable_lx_ready);
+EXPORT_SYMBOL(_pgtable_l4_enabled);
+EXPORT_SYMBOL(_pgtable_l5_enabled);
+EXPORT_SYMBOL(_pgtable_lx_ready);
+bool _pgtable_l4_enabled_early = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
+bool _pgtable_l5_enabled_early = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
+EXPORT_SYMBOL(_pgtable_l4_enabled_early);
+EXPORT_SYMBOL(_pgtable_l5_enabled_early);
 
 phys_addr_t phys_ram_base __ro_after_init;
 EXPORT_SYMBOL(phys_ram_base);
@@ -555,26 +561,26 @@ static void __init create_p4d_mapping(p4d_t *p4dp,
 }
 
 #define pgd_next_t		p4d_t
-#define alloc_pgd_next(__va)	(pgtable_l5_enabled ?			\
-		pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ?		\
+#define alloc_pgd_next(__va)	(pgtable_l5_enabled() ?			\
+		pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled() ?	\
 		pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
-#define get_pgd_next_virt(__pa)	(pgtable_l5_enabled ?			\
-		pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ?	\
+#define get_pgd_next_virt(__pa)	(pgtable_l5_enabled() ?			\
+		pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled() ?	\
 		pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
-				(pgtable_l5_enabled ?			\
+				(pgtable_l5_enabled() ?			\
 		create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
-				(pgtable_l4_enabled ?			\
+				(pgtable_l4_enabled() ?			\
 		create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) :	\
 		create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
-#define fixmap_pgd_next		(pgtable_l5_enabled ?			\
-		(uintptr_t)fixmap_p4d : (pgtable_l4_enabled ?		\
+#define fixmap_pgd_next		(pgtable_l5_enabled() ?			\
+		(uintptr_t)fixmap_p4d : (pgtable_l4_enabled() ?		\
 		(uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
-#define trampoline_pgd_next	(pgtable_l5_enabled ?			\
-		(uintptr_t)trampoline_p4d : (pgtable_l4_enabled ?	\
+#define trampoline_pgd_next	(pgtable_l5_enabled() ?			\
+		(uintptr_t)trampoline_p4d : (pgtable_l4_enabled() ?	\
 		(uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
-#define early_dtb_pgd_next	(pgtable_l5_enabled ?			\
-		(uintptr_t)early_dtb_p4d : (pgtable_l4_enabled ?	\
+#define early_dtb_pgd_next	(pgtable_l5_enabled() ?			\
+		(uintptr_t)early_dtb_p4d : (pgtable_l4_enabled() ?	\
 		(uintptr_t)early_dtb_pud : (uintptr_t)early_dtb_pmd))
 #else
 #define pgd_next_t		pte_t
@@ -680,14 +686,14 @@ static __init pgprot_t pgprot_from_va(uintptr_t va)
 #ifdef CONFIG_64BIT
 static void __init disable_pgtable_l5(void)
 {
-	pgtable_l5_enabled = false;
+	_pgtable_l5_enabled_early = false;
 	kernel_map.page_offset = PAGE_OFFSET_L4;
 	satp_mode = SATP_MODE_48;
 }
 
 static void __init disable_pgtable_l4(void)
 {
-	pgtable_l4_enabled = false;
+	_pgtable_l4_enabled_early = false;
 	kernel_map.page_offset = PAGE_OFFSET_L3;
 	satp_mode = SATP_MODE_39;
 }
@@ -816,11 +822,11 @@ static void __init create_fdt_early_page_table(pgd_t *pgdir, uintptr_t dtb_pa)
 			   PGDIR_SIZE,
 			   IS_ENABLED(CONFIG_64BIT) ? PAGE_TABLE : PAGE_KERNEL);
 
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		create_p4d_mapping(early_dtb_p4d, DTB_EARLY_BASE_VA,
 				   (uintptr_t)early_dtb_pud, P4D_SIZE, PAGE_TABLE);
 
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		create_pud_mapping(early_dtb_pud, DTB_EARLY_BASE_VA,
 				   (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
 
@@ -961,11 +967,11 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 
 #ifndef __PAGETABLE_PMD_FOLDED
 	/* Setup fixmap P4D and PUD */
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		create_p4d_mapping(fixmap_p4d, FIXADDR_START,
 				   (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
 	/* Setup fixmap PUD and PMD */
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		create_pud_mapping(fixmap_pud, FIXADDR_START,
 				   (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
 	create_pmd_mapping(fixmap_pmd, FIXADDR_START,
@@ -973,10 +979,10 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 	/* Setup trampoline PGD and PMD */
 	create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
 			   trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
 				   (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
 				   (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
 #ifdef CONFIG_XIP_KERNEL
@@ -1165,8 +1171,18 @@ static void __init reserve_crashkernel(void)
 	crashk_res.end = crash_base + crash_size - 1;
 }
 
+static void __init riscv_finalise_pgtable_lx(void)
+{
+	if (_pgtable_l5_enabled_early)
+		static_branch_enable(&_pgtable_l5_enabled);
+	if (_pgtable_l4_enabled_early)
+		static_branch_enable(&_pgtable_l4_enabled);
+	static_branch_enable(&_pgtable_lx_ready);
+}
+
 void __init paging_init(void)
 {
+	riscv_finalise_pgtable_lx();
 	setup_bootmem();
 	setup_vm_final();
 }
diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c
index a22e418dbd82..356044498e8a 100644
--- a/arch/riscv/mm/kasan_init.c
+++ b/arch/riscv/mm/kasan_init.c
@@ -209,15 +209,15 @@ static void __init kasan_populate_p4d(pgd_t *pgd,
 		set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_p4d)), PAGE_TABLE));
 }
 
-#define kasan_early_shadow_pgd_next			(pgtable_l5_enabled ?	\
+#define kasan_early_shadow_pgd_next			(pgtable_l5_enabled() ?	\
 				(uintptr_t)kasan_early_shadow_p4d :		\
-							(pgtable_l4_enabled ?	\
+							(pgtable_l4_enabled() ?	\
 				(uintptr_t)kasan_early_shadow_pud :		\
 				(uintptr_t)kasan_early_shadow_pmd))
 #define kasan_populate_pgd_next(pgdp, vaddr, next, early)			\
-		(pgtable_l5_enabled ?						\
+		(pgtable_l5_enabled() ?						\
 		kasan_populate_p4d(pgdp, vaddr, next, early) :			\
-		(pgtable_l4_enabled ?						\
+		(pgtable_l4_enabled() ?						\
 			kasan_populate_pud(pgdp, vaddr, next, early) :		\
 			kasan_populate_pmd((pud_t *)pgdp, vaddr, next)))
 
@@ -274,7 +274,7 @@ asmlinkage void __init kasan_early_init(void)
 				(__pa((uintptr_t)kasan_early_shadow_pte)),
 				PAGE_TABLE));
 
-	if (pgtable_l4_enabled) {
+	if (pgtable_l4_enabled()) {
 		for (i = 0; i < PTRS_PER_PUD; ++i)
 			set_pud(kasan_early_shadow_pud + i,
 				pfn_pud(PFN_DOWN
@@ -282,7 +282,7 @@ asmlinkage void __init kasan_early_init(void)
 					PAGE_TABLE));
 	}
 
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		for (i = 0; i < PTRS_PER_P4D; ++i)
 			set_p4d(kasan_early_shadow_p4d + i,
 				pfn_p4d(PFN_DOWN
@@ -393,9 +393,9 @@ static void __init kasan_shallow_populate_p4d(pgd_t *pgdp,
 }
 
 #define kasan_shallow_populate_pgd_next(pgdp, vaddr, next)			\
-		(pgtable_l5_enabled ?						\
+		(pgtable_l5_enabled() ?						\
 		kasan_shallow_populate_p4d(pgdp, vaddr, next) :			\
-		(pgtable_l4_enabled ?						\
+		(pgtable_l4_enabled() ?						\
 		kasan_shallow_populate_pud(pgdp, vaddr, next) :			\
 		kasan_shallow_populate_pmd(pgdp, vaddr, next)))
 
-- 
2.34.1


WARNING: multiple messages have this Message-ID
From: Jisheng Zhang <jszhang@kernel.org>
To: Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	Alexandre Ghiti <alexandre.ghiti@canonical.com>,
	Anup Patel <anup@brainfault.org>,
	Atish Patra <atishp@rivosinc.com>
Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	kasan-dev@googlegroups.com
Subject: [PATCH v4 2/2] riscv: turn pgtable_l4|[l5]_enabled to static key for RV64
Date: Sat, 21 May 2022 22:34:56 +0800	[thread overview]
Message-ID: <20220521143456.2759-3-jszhang@kernel.org> (raw)
In-Reply-To: <20220521143456.2759-1-jszhang@kernel.org>

On a specific HW platform, pgtable_l4|[l5]_enabled won't change after
boot, and the check sits at hot code path, this characteristic makes it
suitable for optimization with static key.

_pgtable_l4|[l5]_enabled is used very early during boot, even is used
with MMU off, so the static key mechanism isn't ready. For this case,
we use another static key _pgtable_lx_ready to indicate whether we
have finalised pgtable_l4|[l5]_enabled or not, then fall back to
_pgtable_l4|[l5]_enabled_early bool.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
 arch/riscv/include/asm/pgalloc.h    | 16 ++++----
 arch/riscv/include/asm/pgtable-32.h |  3 ++
 arch/riscv/include/asm/pgtable-64.h | 60 ++++++++++++++++++---------
 arch/riscv/include/asm/pgtable.h    |  5 +--
 arch/riscv/kernel/cpu.c             |  4 +-
 arch/riscv/mm/init.c                | 64 ++++++++++++++++++-----------
 arch/riscv/mm/kasan_init.c          | 16 ++++----
 7 files changed, 103 insertions(+), 65 deletions(-)

diff --git a/arch/riscv/include/asm/pgalloc.h b/arch/riscv/include/asm/pgalloc.h
index 947f23d7b6af..0280eeb4756f 100644
--- a/arch/riscv/include/asm/pgalloc.h
+++ b/arch/riscv/include/asm/pgalloc.h
@@ -41,7 +41,7 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 
 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 {
-	if (pgtable_l4_enabled) {
+	if (pgtable_l4_enabled()) {
 		unsigned long pfn = virt_to_pfn(pud);
 
 		set_p4d(p4d, __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
@@ -51,7 +51,7 @@ static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d,
 				     pud_t *pud)
 {
-	if (pgtable_l4_enabled) {
+	if (pgtable_l4_enabled()) {
 		unsigned long pfn = virt_to_pfn(pud);
 
 		set_p4d_safe(p4d,
@@ -61,7 +61,7 @@ static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d,
 
 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 {
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		unsigned long pfn = virt_to_pfn(p4d);
 
 		set_pgd(pgd, __pgd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
@@ -71,7 +71,7 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd,
 				     p4d_t *p4d)
 {
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		unsigned long pfn = virt_to_pfn(p4d);
 
 		set_pgd_safe(pgd,
@@ -82,7 +82,7 @@ static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd,
 #define pud_alloc_one pud_alloc_one
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return __pud_alloc_one(mm, addr);
 
 	return NULL;
@@ -91,7 +91,7 @@ static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
 #define pud_free pud_free
 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		__pud_free(mm, pud);
 }
 
@@ -100,7 +100,7 @@ static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 #define p4d_alloc_one p4d_alloc_one
 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		gfp_t gfp = GFP_PGTABLE_USER;
 
 		if (mm == &init_mm)
@@ -120,7 +120,7 @@ static inline void __p4d_free(struct mm_struct *mm, p4d_t *p4d)
 #define p4d_free p4d_free
 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		__p4d_free(mm, p4d);
 }
 
diff --git a/arch/riscv/include/asm/pgtable-32.h b/arch/riscv/include/asm/pgtable-32.h
index 5b2e79e5bfa5..8af36d76b70d 100644
--- a/arch/riscv/include/asm/pgtable-32.h
+++ b/arch/riscv/include/asm/pgtable-32.h
@@ -16,4 +16,7 @@
 
 #define MAX_POSSIBLE_PHYSMEM_BITS 34
 
+#define pgtable_l5_enabled() 0
+#define pgtable_l4_enabled() 0
+
 #endif /* _ASM_RISCV_PGTABLE_32_H */
diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
index 7e246e9f8d70..d14a3a8f1f4b 100644
--- a/arch/riscv/include/asm/pgtable-64.h
+++ b/arch/riscv/include/asm/pgtable-64.h
@@ -7,17 +7,37 @@
 #define _ASM_RISCV_PGTABLE_64_H
 
 #include <linux/const.h>
+#include <linux/jump_label.h>
 
-extern bool pgtable_l4_enabled;
-extern bool pgtable_l5_enabled;
+extern bool _pgtable_l5_enabled_early;
+extern bool _pgtable_l4_enabled_early;
+extern struct static_key_false _pgtable_l5_enabled;
+extern struct static_key_false _pgtable_l4_enabled;
+extern struct static_key_false _pgtable_lx_ready;
+
+static __always_inline bool pgtable_l5_enabled(void)
+{
+	if (static_branch_likely(&_pgtable_lx_ready))
+		return static_branch_likely(&_pgtable_l5_enabled);
+	else
+		return _pgtable_l5_enabled_early;
+}
+
+static __always_inline bool pgtable_l4_enabled(void)
+{
+	if (static_branch_likely(&_pgtable_lx_ready))
+		return static_branch_likely(&_pgtable_l4_enabled);
+	else
+		return _pgtable_l4_enabled_early;
+}
 
 #define PGDIR_SHIFT_L3  30
 #define PGDIR_SHIFT_L4  39
 #define PGDIR_SHIFT_L5  48
 #define PGDIR_SIZE_L3   (_AC(1, UL) << PGDIR_SHIFT_L3)
 
-#define PGDIR_SHIFT     (pgtable_l5_enabled ? PGDIR_SHIFT_L5 : \
-		(pgtable_l4_enabled ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3))
+#define PGDIR_SHIFT     (pgtable_l5_enabled() ? PGDIR_SHIFT_L5 : \
+		(pgtable_l4_enabled() ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3))
 /* Size of region mapped by a page global directory */
 #define PGDIR_SIZE      (_AC(1, UL) << PGDIR_SHIFT)
 #define PGDIR_MASK      (~(PGDIR_SIZE - 1))
@@ -119,7 +139,7 @@ static inline struct page *pud_page(pud_t pud)
 #define mm_p4d_folded  mm_p4d_folded
 static inline bool mm_p4d_folded(struct mm_struct *mm)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return false;
 
 	return true;
@@ -128,7 +148,7 @@ static inline bool mm_p4d_folded(struct mm_struct *mm)
 #define mm_pud_folded  mm_pud_folded
 static inline bool mm_pud_folded(struct mm_struct *mm)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return false;
 
 	return true;
@@ -159,7 +179,7 @@ static inline unsigned long _pmd_pfn(pmd_t pmd)
 
 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		*p4dp = p4d;
 	else
 		set_pud((pud_t *)p4dp, (pud_t){ p4d_val(p4d) });
@@ -167,7 +187,7 @@ static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
 
 static inline int p4d_none(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return (p4d_val(p4d) == 0);
 
 	return 0;
@@ -175,7 +195,7 @@ static inline int p4d_none(p4d_t p4d)
 
 static inline int p4d_present(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return (p4d_val(p4d) & _PAGE_PRESENT);
 
 	return 1;
@@ -183,7 +203,7 @@ static inline int p4d_present(p4d_t p4d)
 
 static inline int p4d_bad(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return !p4d_present(p4d);
 
 	return 0;
@@ -191,7 +211,7 @@ static inline int p4d_bad(p4d_t p4d)
 
 static inline void p4d_clear(p4d_t *p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		set_p4d(p4d, __p4d(0));
 }
 
@@ -207,7 +227,7 @@ static inline unsigned long _p4d_pfn(p4d_t p4d)
 
 static inline pud_t *p4d_pgtable(p4d_t p4d)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return (pud_t *)pfn_to_virt(p4d_val(p4d) >> _PAGE_PFN_SHIFT);
 
 	return (pud_t *)pud_pgtable((pud_t) { p4d_val(p4d) });
@@ -224,7 +244,7 @@ static inline struct page *p4d_page(p4d_t p4d)
 #define pud_offset pud_offset
 static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
 {
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		return p4d_pgtable(*p4d) + pud_index(address);
 
 	return (pud_t *)p4d;
@@ -232,7 +252,7 @@ static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
 
 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		*pgdp = pgd;
 	else
 		set_p4d((p4d_t *)pgdp, (p4d_t){ pgd_val(pgd) });
@@ -240,7 +260,7 @@ static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 
 static inline int pgd_none(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return (pgd_val(pgd) == 0);
 
 	return 0;
@@ -248,7 +268,7 @@ static inline int pgd_none(pgd_t pgd)
 
 static inline int pgd_present(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return (pgd_val(pgd) & _PAGE_PRESENT);
 
 	return 1;
@@ -256,7 +276,7 @@ static inline int pgd_present(pgd_t pgd)
 
 static inline int pgd_bad(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return !pgd_present(pgd);
 
 	return 0;
@@ -264,13 +284,13 @@ static inline int pgd_bad(pgd_t pgd)
 
 static inline void pgd_clear(pgd_t *pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		set_pgd(pgd, __pgd(0));
 }
 
 static inline p4d_t *pgd_pgtable(pgd_t pgd)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return (p4d_t *)pfn_to_virt(pgd_val(pgd) >> _PAGE_PFN_SHIFT);
 
 	return (p4d_t *)p4d_pgtable((p4d_t) { pgd_val(pgd) });
@@ -288,7 +308,7 @@ static inline struct page *pgd_page(pgd_t pgd)
 #define p4d_offset p4d_offset
 static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		return pgd_pgtable(*pgd) + p4d_index(address);
 
 	return (p4d_t *)pgd;
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 046b44225623..ae01a9b83ac4 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -63,8 +63,8 @@
  * position vmemmap directly below the VMALLOC region.
  */
 #ifdef CONFIG_64BIT
-#define VA_BITS		(pgtable_l5_enabled ? \
-				57 : (pgtable_l4_enabled ? 48 : 39))
+#define VA_BITS		(pgtable_l5_enabled() ? \
+				57 : (pgtable_l4_enabled() ? 48 : 39))
 #else
 #define VA_BITS		32
 #endif
@@ -738,7 +738,6 @@ extern uintptr_t _dtb_early_pa;
 #define dtb_early_pa	_dtb_early_pa
 #endif /* CONFIG_XIP_KERNEL */
 extern u64 satp_mode;
-extern bool pgtable_l4_enabled;
 
 void paging_init(void);
 void misc_mem_init(void);
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index ccb617791e56..29bb0ef75248 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -141,9 +141,9 @@ static void print_mmu(struct seq_file *f)
 #if defined(CONFIG_32BIT)
 	strncpy(sv_type, "sv32", 5);
 #elif defined(CONFIG_64BIT)
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		strncpy(sv_type, "sv57", 5);
-	else if (pgtable_l4_enabled)
+	else if (pgtable_l4_enabled())
 		strncpy(sv_type, "sv48", 5);
 	else
 		strncpy(sv_type, "sv39", 5);
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 05ed641a1134..42c79388e6fd 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -44,10 +44,16 @@ u64 satp_mode __ro_after_init = SATP_MODE_32;
 #endif
 EXPORT_SYMBOL(satp_mode);
 
-bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
-bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
-EXPORT_SYMBOL(pgtable_l4_enabled);
-EXPORT_SYMBOL(pgtable_l5_enabled);
+DEFINE_STATIC_KEY_FALSE(_pgtable_l4_enabled);
+DEFINE_STATIC_KEY_FALSE(_pgtable_l5_enabled);
+DEFINE_STATIC_KEY_FALSE(_pgtable_lx_ready);
+EXPORT_SYMBOL(_pgtable_l4_enabled);
+EXPORT_SYMBOL(_pgtable_l5_enabled);
+EXPORT_SYMBOL(_pgtable_lx_ready);
+bool _pgtable_l4_enabled_early = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
+bool _pgtable_l5_enabled_early = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
+EXPORT_SYMBOL(_pgtable_l4_enabled_early);
+EXPORT_SYMBOL(_pgtable_l5_enabled_early);
 
 phys_addr_t phys_ram_base __ro_after_init;
 EXPORT_SYMBOL(phys_ram_base);
@@ -555,26 +561,26 @@ static void __init create_p4d_mapping(p4d_t *p4dp,
 }
 
 #define pgd_next_t		p4d_t
-#define alloc_pgd_next(__va)	(pgtable_l5_enabled ?			\
-		pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ?		\
+#define alloc_pgd_next(__va)	(pgtable_l5_enabled() ?			\
+		pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled() ?	\
 		pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
-#define get_pgd_next_virt(__pa)	(pgtable_l5_enabled ?			\
-		pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ?	\
+#define get_pgd_next_virt(__pa)	(pgtable_l5_enabled() ?			\
+		pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled() ?	\
 		pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
-				(pgtable_l5_enabled ?			\
+				(pgtable_l5_enabled() ?			\
 		create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
-				(pgtable_l4_enabled ?			\
+				(pgtable_l4_enabled() ?			\
 		create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) :	\
 		create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
-#define fixmap_pgd_next		(pgtable_l5_enabled ?			\
-		(uintptr_t)fixmap_p4d : (pgtable_l4_enabled ?		\
+#define fixmap_pgd_next		(pgtable_l5_enabled() ?			\
+		(uintptr_t)fixmap_p4d : (pgtable_l4_enabled() ?		\
 		(uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
-#define trampoline_pgd_next	(pgtable_l5_enabled ?			\
-		(uintptr_t)trampoline_p4d : (pgtable_l4_enabled ?	\
+#define trampoline_pgd_next	(pgtable_l5_enabled() ?			\
+		(uintptr_t)trampoline_p4d : (pgtable_l4_enabled() ?	\
 		(uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
-#define early_dtb_pgd_next	(pgtable_l5_enabled ?			\
-		(uintptr_t)early_dtb_p4d : (pgtable_l4_enabled ?	\
+#define early_dtb_pgd_next	(pgtable_l5_enabled() ?			\
+		(uintptr_t)early_dtb_p4d : (pgtable_l4_enabled() ?	\
 		(uintptr_t)early_dtb_pud : (uintptr_t)early_dtb_pmd))
 #else
 #define pgd_next_t		pte_t
@@ -680,14 +686,14 @@ static __init pgprot_t pgprot_from_va(uintptr_t va)
 #ifdef CONFIG_64BIT
 static void __init disable_pgtable_l5(void)
 {
-	pgtable_l5_enabled = false;
+	_pgtable_l5_enabled_early = false;
 	kernel_map.page_offset = PAGE_OFFSET_L4;
 	satp_mode = SATP_MODE_48;
 }
 
 static void __init disable_pgtable_l4(void)
 {
-	pgtable_l4_enabled = false;
+	_pgtable_l4_enabled_early = false;
 	kernel_map.page_offset = PAGE_OFFSET_L3;
 	satp_mode = SATP_MODE_39;
 }
@@ -816,11 +822,11 @@ static void __init create_fdt_early_page_table(pgd_t *pgdir, uintptr_t dtb_pa)
 			   PGDIR_SIZE,
 			   IS_ENABLED(CONFIG_64BIT) ? PAGE_TABLE : PAGE_KERNEL);
 
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		create_p4d_mapping(early_dtb_p4d, DTB_EARLY_BASE_VA,
 				   (uintptr_t)early_dtb_pud, P4D_SIZE, PAGE_TABLE);
 
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		create_pud_mapping(early_dtb_pud, DTB_EARLY_BASE_VA,
 				   (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
 
@@ -961,11 +967,11 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 
 #ifndef __PAGETABLE_PMD_FOLDED
 	/* Setup fixmap P4D and PUD */
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		create_p4d_mapping(fixmap_p4d, FIXADDR_START,
 				   (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
 	/* Setup fixmap PUD and PMD */
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		create_pud_mapping(fixmap_pud, FIXADDR_START,
 				   (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
 	create_pmd_mapping(fixmap_pmd, FIXADDR_START,
@@ -973,10 +979,10 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 	/* Setup trampoline PGD and PMD */
 	create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
 			   trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
 				   (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
-	if (pgtable_l4_enabled)
+	if (pgtable_l4_enabled())
 		create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
 				   (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
 #ifdef CONFIG_XIP_KERNEL
@@ -1165,8 +1171,18 @@ static void __init reserve_crashkernel(void)
 	crashk_res.end = crash_base + crash_size - 1;
 }
 
+static void __init riscv_finalise_pgtable_lx(void)
+{
+	if (_pgtable_l5_enabled_early)
+		static_branch_enable(&_pgtable_l5_enabled);
+	if (_pgtable_l4_enabled_early)
+		static_branch_enable(&_pgtable_l4_enabled);
+	static_branch_enable(&_pgtable_lx_ready);
+}
+
 void __init paging_init(void)
 {
+	riscv_finalise_pgtable_lx();
 	setup_bootmem();
 	setup_vm_final();
 }
diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c
index a22e418dbd82..356044498e8a 100644
--- a/arch/riscv/mm/kasan_init.c
+++ b/arch/riscv/mm/kasan_init.c
@@ -209,15 +209,15 @@ static void __init kasan_populate_p4d(pgd_t *pgd,
 		set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_p4d)), PAGE_TABLE));
 }
 
-#define kasan_early_shadow_pgd_next			(pgtable_l5_enabled ?	\
+#define kasan_early_shadow_pgd_next			(pgtable_l5_enabled() ?	\
 				(uintptr_t)kasan_early_shadow_p4d :		\
-							(pgtable_l4_enabled ?	\
+							(pgtable_l4_enabled() ?	\
 				(uintptr_t)kasan_early_shadow_pud :		\
 				(uintptr_t)kasan_early_shadow_pmd))
 #define kasan_populate_pgd_next(pgdp, vaddr, next, early)			\
-		(pgtable_l5_enabled ?						\
+		(pgtable_l5_enabled() ?						\
 		kasan_populate_p4d(pgdp, vaddr, next, early) :			\
-		(pgtable_l4_enabled ?						\
+		(pgtable_l4_enabled() ?						\
 			kasan_populate_pud(pgdp, vaddr, next, early) :		\
 			kasan_populate_pmd((pud_t *)pgdp, vaddr, next)))
 
@@ -274,7 +274,7 @@ asmlinkage void __init kasan_early_init(void)
 				(__pa((uintptr_t)kasan_early_shadow_pte)),
 				PAGE_TABLE));
 
-	if (pgtable_l4_enabled) {
+	if (pgtable_l4_enabled()) {
 		for (i = 0; i < PTRS_PER_PUD; ++i)
 			set_pud(kasan_early_shadow_pud + i,
 				pfn_pud(PFN_DOWN
@@ -282,7 +282,7 @@ asmlinkage void __init kasan_early_init(void)
 					PAGE_TABLE));
 	}
 
-	if (pgtable_l5_enabled) {
+	if (pgtable_l5_enabled()) {
 		for (i = 0; i < PTRS_PER_P4D; ++i)
 			set_p4d(kasan_early_shadow_p4d + i,
 				pfn_p4d(PFN_DOWN
@@ -393,9 +393,9 @@ static void __init kasan_shallow_populate_p4d(pgd_t *pgdp,
 }
 
 #define kasan_shallow_populate_pgd_next(pgdp, vaddr, next)			\
-		(pgtable_l5_enabled ?						\
+		(pgtable_l5_enabled() ?						\
 		kasan_shallow_populate_p4d(pgdp, vaddr, next) :			\
-		(pgtable_l4_enabled ?						\
+		(pgtable_l4_enabled() ?						\
 		kasan_shallow_populate_pud(pgdp, vaddr, next) :			\
 		kasan_shallow_populate_pmd(pgdp, vaddr, next)))
 
-- 
2.34.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

  parent reply	other threads:[~2022-05-21 14:43 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-21 14:34 [PATCH v4 0/2] use static key to optimize pgtable_l4_enabled Jisheng Zhang
2022-05-21 14:34 ` Jisheng Zhang
2022-05-21 14:34 ` [PATCH v4 1/2] riscv: move sbi_init() earlier before jump_label_init() Jisheng Zhang
2022-05-21 14:34   ` Jisheng Zhang
2022-05-22  8:01   ` Atish Patra
2022-05-22  8:01     ` Atish Patra
2022-06-26  4:32   ` Anup Patel
2022-06-26  4:32     ` Anup Patel
2022-06-27  6:47     ` Atish Patra
2022-06-27  6:47       ` Atish Patra
2022-05-21 14:34 ` Jisheng Zhang [this message]
2022-05-21 14:34   ` [PATCH v4 2/2] riscv: turn pgtable_l4|[l5]_enabled to static key for RV64 Jisheng Zhang
2022-05-24 15:59   ` Anup Patel
2022-05-24 15:59     ` Anup Patel
2022-06-05  6:12     ` Jisheng Zhang
2022-06-05  6:12       ` Jisheng Zhang
2022-06-26  4:33 ` [PATCH v4 0/2] use static key to optimize pgtable_l4_enabled Anup Patel
2022-06-26  4:33   ` Anup Patel
2022-07-02  3:48   ` Palmer Dabbelt
2022-07-02  3:48     ` Palmer Dabbelt
2022-07-15 13:35     ` Jisheng Zhang
2022-07-15 13:35       ` Jisheng Zhang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220521143456.2759-3-jszhang@kernel.org \
    --to=jszhang@kernel.org \
    --cc=alexandre.ghiti@canonical.com \
    --cc=andreyknvl@gmail.com \
    --cc=anup@brainfault.org \
    --cc=aou@eecs.berkeley.edu \
    --cc=atishp@rivosinc.com \
    --cc=dvyukov@google.com \
    --cc=glider@google.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=palmer@dabbelt.com \
    --cc=paul.walmsley@sifive.com \
    --cc=ryabinin.a.a@gmail.com \
    --cc=vincenzo.frascino@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.