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(unknown [124.16.141.243]) by APP-03 (Coremail) with SMTP id rQCowAAXHNS7A45mMJH4FA--.46888S2; Wed, 10 Jul 2024 11:45:00 +0800 (CST) From: Chunyan Zhang To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Andrew Morton Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Chunyan Zhang Subject: [PATCH] riscv/mm: Add soft-dirty page tracking support Date: Wed, 10 Jul 2024 11:30:04 +0800 Message-Id: <20240710033004.3923527-1-zhangchunyan@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: rQCowAAXHNS7A45mMJH4FA--.46888S2 X-Coremail-Antispam: 1UD129KBjvJXoWxAw4DWF4kXw1rWrW5Kw4fGrg_yoWrKr1kpF Z5GF1rZayYyFn7Kayftr4agrWY9wn3Wa4UXry3Ca1kJayUGrWUXF98Wry3Zry5XFykZ34f ZrZ5tF45Crsrtr7anT9S1TB71UUUUUDqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUyab7Iv0xC_KF4lb4IE77IF4wAFF20E14v26r4j6ryUM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rw A2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xII jxv20xvEc7CjxVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwV C2z280aVCY1x0267AKxVWxJr0_GcWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xv F2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r 4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwCF04k20xvY0x0EwIxGrwCF x2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14 v26r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY 67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Jr0_Gr1lIxAIcVCF04k26cxKx2 IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_ Jr0_GrUvcSsGvfC2KfnxnUUI43ZEXa7IU8IzuJUUUUU== X-CM-SenderInfo: x2kd0wxfkx051dq6x2xfdvhtffof0/1tbiCREOB2aNsCzIUwABs8 Content-Type: text/plain; charset="utf-8" The PTE bit (9) is reserved for software, so we can use it for soft-dirty tracking. This patch adds its standard handlers for PTE, PMD, and swap entry. To add swap PTE soft-dirty tracking, we borrow bit (4) which is available for swap PTEs on RISC-V systems. This patch has been tested with the kselftest mm suite in which soft-dirty and madv_populate run and pass, and no regressions are observed in any of the other tests. Signed-off-by: Chunyan Zhang --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable-bits.h | 13 ++++++ arch/riscv/include/asm/pgtable.h | 65 ++++++++++++++++++++++++++- 3 files changed, 78 insertions(+), 1 deletion(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index b94176e25be1..2e3ad2925a6b 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -118,6 +118,7 @@ config RISCV select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET select HAVE_ARCH_SECCOMP_FILTER + select HAVE_ARCH_SOFT_DIRTY select HAVE_ARCH_THREAD_STRUCT_WHITELIST select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm= /pgtable-bits.h index 179bd4afece4..bab48f5fd1e2 100644 --- a/arch/riscv/include/asm/pgtable-bits.h +++ b/arch/riscv/include/asm/pgtable-bits.h @@ -19,6 +19,19 @@ #define _PAGE_SOFT (3 << 8) /* Reserved for software */ =20 #define _PAGE_SPECIAL (1 << 8) /* RSW: 0x1 */ + +#ifdef CONFIG_MEM_SOFT_DIRTY +#define _PAGE_SOFT_DIRTY (1 << 9) /* RSW: 0x2 for software dirty tracki= ng */ +/* + * BIT 4 is not involved into swap entry computation, so we + * can borrow it for swap page soft-dirty tracking. + */ +#define _PAGE_SWP_SOFT_DIRTY _PAGE_USER +#else +#define _PAGE_SOFT_DIRTY 0 +#define _PAGE_SWP_SOFT_DIRTY 0 +#endif /* CONFIG_MEM_SOFT_DIRTY */ + #define _PAGE_TABLE _PAGE_PRESENT =20 /* diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgta= ble.h index aad8b8ca51f1..46f512f52580 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -408,7 +408,7 @@ static inline pte_t pte_mkwrite_novma(pte_t pte) =20 static inline pte_t pte_mkdirty(pte_t pte) { - return __pte(pte_val(pte) | _PAGE_DIRTY); + return __pte(pte_val(pte) | _PAGE_DIRTY | _PAGE_SOFT_DIRTY); } =20 static inline pte_t pte_mkclean(pte_t pte) @@ -436,6 +436,36 @@ static inline pte_t pte_mkhuge(pte_t pte) return pte; } =20 +static inline int pte_soft_dirty(pte_t pte) +{ + return pte_val(pte) & _PAGE_SOFT_DIRTY; +} + +static inline pte_t pte_mksoft_dirty(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_SOFT_DIRTY); +} + +static inline pte_t pte_clear_soft_dirty(pte_t pte) +{ + return __pte(pte_val(pte) & ~(_PAGE_SOFT_DIRTY)); +} + +static inline int pte_swp_soft_dirty(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_SOFT_DIRTY; +} + +static inline pte_t pte_swp_mksoft_dirty(pte_t pte) +{ + return __pte(pte_val(pte) | _PAGE_SWP_SOFT_DIRTY); +} + +static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) +{ + return __pte(pte_val(pte) & ~(_PAGE_SWP_SOFT_DIRTY)); +} + #ifdef CONFIG_RISCV_ISA_SVNAPOT #define pte_leaf_size(pte) (pte_napot(pte) ? \ napot_cont_size(napot_cont_order(pte)) :\ @@ -721,6 +751,38 @@ static inline pmd_t pmd_mkdirty(pmd_t pmd) return pte_pmd(pte_mkdirty(pmd_pte(pmd))); } =20 +static inline int pmd_soft_dirty(pmd_t pmd) +{ + return pte_soft_dirty(pmd_pte(pmd)); +} + +static inline pmd_t pmd_mksoft_dirty(pmd_t pmd) +{ + return pte_pmd(pte_mksoft_dirty(pmd_pte(pmd))); +} + +static inline pmd_t pmd_clear_soft_dirty(pmd_t pmd) +{ + return pte_pmd(pte_clear_soft_dirty(pmd_pte(pmd))); +} + +#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION +static inline int pmd_swp_soft_dirty(pmd_t pmd) +{ + return pte_swp_soft_dirty(pmd_pte(pmd)); +} + +static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd) +{ + return pte_pmd(pte_swp_mksoft_dirty(pmd_pte(pmd))); +} + +static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd) +{ + return pte_pmd(pte_swp_clear_soft_dirty(pmd_pte(pmd))); +} +#endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */ + static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd) { @@ -811,6 +873,7 @@ extern pmd_t pmdp_collapse_flush(struct vm_area_struct = *vma, * Format of swap PTE: * bit 0: _PAGE_PRESENT (zero) * bit 1 to 3: _PAGE_LEAF (zero) + * bit 4: _PAGE_SWP_SOFT_DIRTY * bit 5: _PAGE_PROT_NONE (zero) * bit 6: exclusive marker * bits 7 to 11: swap type --=20 2.34.1