On MIPS system which has rixi hardware bit, page access bit is not
set in pgrot. For memory reading, there will be one page fault to
allocate physical page; however valid bit is not set, there will
be the second fast tlb-miss fault handling to set valid/access bit.
This patch set page access/valid bit with pgrot if there is reading
access privilege. It will reduce one tlb-miss handling for memory
reading access.
The valid/access bit will be cleared in order to track memory
accessing activity. If the page is accessed, tlb-miss fast handling
will set valid/access bit, pte_sw_mkyoung is not necessary in slow
page fault path. This patch removes pte_sw_mkyoung function which
is defined as empty function except MIPS system.
Signed-off-by: Bibo Mao <[email protected]>
Acked-by: Andrew Morton <[email protected]>
---
v2:
- refine commit log title
---
arch/mips/include/asm/pgtable.h | 10 ++++++++--
arch/mips/mm/cache.c | 34 +++++++++++++++++-----------------
include/asm-generic/pgtable.h | 16 ----------------
mm/memory.c | 3 ---
4 files changed, 25 insertions(+), 38 deletions(-)
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 85b39c9..d066469 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -25,6 +25,14 @@
struct mm_struct;
struct vm_area_struct;
+#define __PP _PAGE_PRESENT
+#define __NX _PAGE_NO_EXEC
+#define __NR _PAGE_NO_READ
+#define ___W _PAGE_WRITE
+#define ___A _PAGE_ACCESSED
+#define ___R (_PAGE_SILENT_READ | _PAGE_ACCESSED)
+#define __PC _page_cachable_default
+
#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \
_page_cachable_default)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
@@ -414,8 +422,6 @@ static inline pte_t pte_mkyoung(pte_t pte)
return pte;
}
-#define pte_sw_mkyoung pte_mkyoung
-
#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE; }
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index ad6df1c..f814e43 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -158,23 +158,23 @@ void __update_cache(unsigned long address, pte_t pte)
static inline void setup_protection_map(void)
{
if (cpu_has_rixi) {
- protection_map[0] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[1] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[2] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[3] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[4] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[5] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[6] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[7] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
-
- protection_map[8] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[9] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
- protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
- protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
- protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
+ protection_map[0] = __pgprot(__PC | __PP | __NX | __NR);
+ protection_map[1] = __pgprot(__PC | __PP | __NX | ___R);
+ protection_map[2] = __pgprot(__PC | __PP | __NX | __NR);
+ protection_map[3] = __pgprot(__PC | __PP | __NX | ___R);
+ protection_map[4] = __pgprot(__PC | __PP | ___R);
+ protection_map[5] = __pgprot(__PC | __PP | ___R);
+ protection_map[6] = __pgprot(__PC | __PP | ___R);
+ protection_map[7] = __pgprot(__PC | __PP | ___R);
+
+ protection_map[8] = __pgprot(__PC | __PP | __NX | __NR);
+ protection_map[9] = __pgprot(__PC | __PP | __NX | ___R);
+ protection_map[10] = __pgprot(__PC | __PP | __NX | ___W | __NR);
+ protection_map[11] = __pgprot(__PC | __PP | __NX | ___W | ___R);
+ protection_map[12] = __pgprot(__PC | __PP | ___R);
+ protection_map[13] = __pgprot(__PC | __PP | ___R);
+ protection_map[14] = __pgprot(__PC | __PP | ___W | ___R);
+ protection_map[15] = __pgprot(__PC | __PP | ___W | ___R);
} else {
protection_map[0] = PAGE_NONE;
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index b5278ec..fa5c73f 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -244,22 +244,6 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres
}
#endif
-/*
- * On some architectures hardware does not set page access bit when accessing
- * memory page, it is responsibilty of software setting this bit. It brings
- * out extra page fault penalty to track page access bit. For optimization page
- * access bit can be set during all page fault flow on these arches.
- * To be differentiate with macro pte_mkyoung, this macro is used on platforms
- * where software maintains page access bit.
- */
-#ifndef pte_sw_mkyoung
-static inline pte_t pte_sw_mkyoung(pte_t pte)
-{
- return pte;
-}
-#define pte_sw_mkyoung pte_sw_mkyoung
-#endif
-
#ifndef pte_savedwrite
#define pte_savedwrite pte_write
#endif
diff --git a/mm/memory.c b/mm/memory.c
index c7c8960..8bb31c4 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2704,7 +2704,6 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
}
flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));
entry = mk_pte(new_page, vma->vm_page_prot);
- entry = pte_sw_mkyoung(entry);
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
/*
* Clear the pte entry and flush it first, before updating the
@@ -3379,7 +3378,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
__SetPageUptodate(page);
entry = mk_pte(page, vma->vm_page_prot);
- entry = pte_sw_mkyoung(entry);
if (vma->vm_flags & VM_WRITE)
entry = pte_mkwrite(pte_mkdirty(entry));
@@ -3662,7 +3660,6 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
flush_icache_page(vma, page);
entry = mk_pte(page, vma->vm_page_prot);
- entry = pte_sw_mkyoung(entry);
if (write)
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
/* copy-on-write page */
--
1.8.3.1
On Sat, Jun 06, 2020 at 12:02:48PM +0800, Bibo Mao wrote:
> @@ -158,23 +158,23 @@ void __update_cache(unsigned long address, pte_t pte)
> static inline void setup_protection_map(void)
> {
> if (cpu_has_rixi) {
> - protection_map[0] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
> - protection_map[1] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
> - protection_map[2] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
> - protection_map[3] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
> - protection_map[4] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
> - protection_map[5] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
> - protection_map[6] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
> - protection_map[7] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
> -
> - protection_map[8] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
> - protection_map[9] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
> - protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
> - protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
> - protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
> - protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
> - protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
> - protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
> + protection_map[0] = __pgprot(__PC | __PP | __NX | __NR);
> + protection_map[1] = __pgprot(__PC | __PP | __NX | ___R);
> + protection_map[2] = __pgprot(__PC | __PP | __NX | __NR);
> + protection_map[3] = __pgprot(__PC | __PP | __NX | ___R);
> + protection_map[4] = __pgprot(__PC | __PP | ___R);
> + protection_map[5] = __pgprot(__PC | __PP | ___R);
> + protection_map[6] = __pgprot(__PC | __PP | ___R);
> + protection_map[7] = __pgprot(__PC | __PP | ___R);
> +
> + protection_map[8] = __pgprot(__PC | __PP | __NX | __NR);
> + protection_map[9] = __pgprot(__PC | __PP | __NX | ___R);
> + protection_map[10] = __pgprot(__PC | __PP | __NX | ___W | __NR);
> + protection_map[11] = __pgprot(__PC | __PP | __NX | ___W | ___R);
> + protection_map[12] = __pgprot(__PC | __PP | ___R);
> + protection_map[13] = __pgprot(__PC | __PP | ___R);
> + protection_map[14] = __pgprot(__PC | __PP | ___W | ___R);
> + protection_map[15] = __pgprot(__PC | __PP | ___W | ___R);
you are doing two steps in one go, so it's not obvious you are not only
using some macros, but also changing semantics. And while there are already
really long lines, please leave it that way and only do the access bit
change.
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
adjust the code and add support non-rixi
This patch adds support for non-rixi, based on [1].
MIPS page fault path take 3 exception (1 tlb miss + 2 tlb invalid), but
the second tlb invalid exception is just caused by __update_tlb from
do_page_fault writing tlb without _PAGE_VALID set. With this patch, it
only take 1 tlb miss + 1 tlb invalid exceptions
[1]: https://lkml.kernel.org/lkml/[email protected]/
Signed-off-by: Huang Pei <[email protected]>
---
arch/mips/include/asm/pgtable.h | 32 +++++++++++++++-----------------
arch/mips/mm/cache.c | 25 +++++++++++++------------
mm/memory.c | 3 ---
3 files changed, 28 insertions(+), 32 deletions(-)
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index dd7a0f552cac..aaafe3d6a0a1 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -25,22 +25,22 @@
struct mm_struct;
struct vm_area_struct;
-#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \
- _page_cachable_default)
-#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
- _page_cachable_default)
-#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \
- _page_cachable_default)
-#define PAGE_READONLY __pgprot(_PAGE_PRESENT | \
- _page_cachable_default)
-#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
- _PAGE_GLOBAL | _page_cachable_default)
-#define PAGE_KERNEL_NC __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
- _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT)
-#define PAGE_USERIO __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
- _page_cachable_default)
+#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \
+ _page_cachable_default)
+#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
+ __READABLE | _page_cachable_default)
+#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \
+ __READABLE | _page_cachable_default)
+#define PAGE_READONLY __pgprot(_PAGE_PRESENT | __READABLE | \
+ _page_cachable_default)
+#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
+ _PAGE_GLOBAL | _page_cachable_default)
+#define PAGE_KERNEL_NC __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
+ _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT)
+#define PAGE_USERIO __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
+ _page_cachable_default)
#define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
- __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
+ __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
/*
* If _PAGE_NO_EXEC is not defined, we can't do page protection for
@@ -414,8 +414,6 @@ static inline pte_t pte_mkyoung(pte_t pte)
return pte;
}
-#define pte_sw_mkyoung pte_mkyoung
-
#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE; }
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index 3e81ba000096..ed75f2871aad 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -159,22 +159,23 @@ static inline void setup_protection_map(void)
{
if (cpu_has_rixi) {
protection_map[0] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[1] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
+ protection_map[1] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE);
protection_map[2] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[3] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
- protection_map[4] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[5] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[6] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[7] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
+ protection_map[3] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE);
+ protection_map[4] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE);
+ protection_map[5] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE);
+ protection_map[6] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE);
+ protection_map[7] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE);
protection_map[8] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
- protection_map[9] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
+ protection_map[9] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE);
protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
- protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
- protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
- protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
- protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
+ protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | __READABLE);
+ protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE);
+ protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE);
+ protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE);
+ protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE);
+
} else {
protection_map[0] = PAGE_NONE;
diff --git a/mm/memory.c b/mm/memory.c
index 602f4283122f..5100ab5bcf77 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2705,7 +2705,6 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf)
}
flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));
entry = mk_pte(new_page, vma->vm_page_prot);
- entry = pte_sw_mkyoung(entry);
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
/*
* Clear the pte entry and flush it first, before updating the
@@ -3386,7 +3385,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
__SetPageUptodate(page);
entry = mk_pte(page, vma->vm_page_prot);
- entry = pte_sw_mkyoung(entry);
if (vma->vm_flags & VM_WRITE)
entry = pte_mkwrite(pte_mkdirty(entry));
@@ -3661,7 +3659,6 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct page *page)
flush_icache_page(vma, page);
entry = mk_pte(page, vma->vm_page_prot);
- entry = pte_sw_mkyoung(entry);
if (write)
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
/* copy-on-write page */
--
2.17.1