User space checkpoint and restart tool (CRIU) needs the page's change
to be soft tracked. This allows to do a pre checkpoint and then dump
only touched pages.
Signed-off-by: Guoyun Sun <[email protected]>
---
arch/mips/Kconfig | 1 +
arch/mips/include/asm/pgtable-bits.h | 8 ++++--
arch/mips/include/asm/pgtable.h | 48 ++++++++++++++++++++++++++++++++++--
3 files changed, 53 insertions(+), 4 deletions(-)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 690718b..642fb47 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -491,6 +491,7 @@ config MACH_LOONGSON64
select COMMON_CLK
select USE_OF
select BUILTIN_DTB
+ select HAVE_ARCH_SOFT_DIRTY
help
This enables the support of Loongson-2/3 family of machines.
diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h
index 4da79b8..d43fb6f 100644
--- a/arch/mips/include/asm/pgtable-bits.h
+++ b/arch/mips/include/asm/pgtable-bits.h
@@ -55,6 +55,7 @@ enum pgtable_bits {
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
+ _PAGE_SOFT_DIRTY_SHIFT,
};
/*
@@ -84,6 +85,7 @@ enum pgtable_bits {
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
+ _PAGE_SOFT_DIRTY_SHIFT,
};
#elif defined(CONFIG_CPU_R3K_TLB)
@@ -99,6 +101,7 @@ enum pgtable_bits {
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
+ _PAGE_SOFT_DIRTY_SHIFT,
/* Used by TLB hardware (placed in EntryLo) */
_PAGE_GLOBAL_SHIFT = 8,
@@ -125,7 +128,7 @@ enum pgtable_bits {
#if defined(CONFIG_ARCH_HAS_PTE_SPECIAL)
_PAGE_SPECIAL_SHIFT,
#endif
-
+ _PAGE_SOFT_DIRTY_SHIFT,
/* Used by TLB hardware (placed in EntryLo*) */
#if defined(CONFIG_CPU_HAS_RIXI)
_PAGE_NO_EXEC_SHIFT,
@@ -152,6 +155,7 @@ enum pgtable_bits {
#else
# define _PAGE_SPECIAL 0
#endif
+#define _PAGE_SOFT_DIRTY (1 << _PAGE_SOFT_DIRTY_SHIFT)
/* Used by TLB hardware (placed in EntryLo*) */
#if defined(CONFIG_XPA)
@@ -269,6 +273,6 @@ static inline uint64_t pte_to_entrylo(unsigned long pte_val)
#define __WRITEABLE (_PAGE_SILENT_WRITE | _PAGE_WRITE | _PAGE_MODIFIED)
#define _PAGE_CHG_MASK (_PAGE_ACCESSED | _PAGE_MODIFIED | \
- _PFN_MASK | _CACHE_MASK)
+ _PAGE_SOFT_DIRTY | _PFN_MASK | _CACHE_MASK)
#endif /* _ASM_PGTABLE_BITS_H */
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index f1801e7..64b07ff 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -400,7 +400,7 @@ static inline pte_t pte_mkwrite(pte_t pte)
static inline pte_t pte_mkdirty(pte_t pte)
{
- pte_val(pte) |= _PAGE_MODIFIED;
+ pte_val(pte) |= _PAGE_MODIFIED | _PAGE_SOFT_DIRTY;
if (pte_val(pte) & _PAGE_WRITE)
pte_val(pte) |= _PAGE_SILENT_WRITE;
return pte;
@@ -423,6 +423,30 @@ static inline pte_t pte_mkhuge(pte_t pte)
return pte;
}
#endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
+
+#ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
+static inline bool pte_soft_dirty(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_SOFT_DIRTY;
+}
+#define pte_swp_soft_dirty pte_soft_dirty
+
+static inline pte_t pte_mksoft_dirty(pte_t pte)
+{
+ pte_val(pte) |= _PAGE_SOFT_DIRTY;
+ return pte;
+}
+#define pte_swp_mksoft_dirty pte_mksoft_dirty
+
+static inline pte_t pte_clear_soft_dirty(pte_t pte)
+{
+ pte_val(pte) &= ~(_PAGE_SOFT_DIRTY);
+ return pte;
+}
+#define pte_swp_clear_soft_dirty pte_clear_soft_dirty
+
+#endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
+
#endif
/*
@@ -579,7 +603,7 @@ static inline pmd_t pmd_mkclean(pmd_t pmd)
static inline pmd_t pmd_mkdirty(pmd_t pmd)
{
- pmd_val(pmd) |= _PAGE_MODIFIED;
+ pmd_val(pmd) |= _PAGE_MODIFIED | _PAGE_SOFT_DIRTY;
if (pmd_val(pmd) & _PAGE_WRITE)
pmd_val(pmd) |= _PAGE_SILENT_WRITE;
@@ -608,6 +632,26 @@ static inline pmd_t pmd_mkyoung(pmd_t pmd)
return pmd;
}
+#ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
+static inline int pmd_soft_dirty(pmd_t pmd)
+{
+ return !!(pmd_val(pmd) & _PAGE_SOFT_DIRTY);
+}
+
+static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
+{
+ pmd_val(pmd) |= _PAGE_SOFT_DIRTY;
+ return pmd;
+}
+
+static inline pmd_t pmd_clear_soft_dirty(pmd_t pmd)
+{
+ pmd_val(pmd) &= ~(_PAGE_SOFT_DIRTY);
+ return pmd;
+}
+
+#endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
+
/* Extern to avoid header file madness */
extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
--
2.1.0
On Tue, Apr 21, 2020 at 05:15:27PM +0800, Guoyun Sun wrote:
> User space checkpoint and restart tool (CRIU) needs the page's change
> to be soft tracked. This allows to do a pre checkpoint and then dump
> only touched pages.
>
> Signed-off-by: Guoyun Sun <[email protected]>
> ---
> arch/mips/Kconfig | 1 +
> arch/mips/include/asm/pgtable-bits.h | 8 ++++--
> arch/mips/include/asm/pgtable.h | 48 ++++++++++++++++++++++++++++++++++--
this breaks all 32bit builds where CPU support RIXI, because it overflows
pgtable_bits.
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
Hi Thomas,
Le dim. 26 avril 2020 ? 18:54, Thomas Bogendoerfer
<[email protected]> a ?crit :
> On Tue, Apr 21, 2020 at 05:15:27PM +0800, Guoyun Sun wrote:
>> User space checkpoint and restart tool (CRIU) needs the page's
>> change
>> to be soft tracked. This allows to do a pre checkpoint and then dump
>> only touched pages.
>>
>> Signed-off-by: Guoyun Sun <[email protected]>
>> ---
>> arch/mips/Kconfig | 1 +
>> arch/mips/include/asm/pgtable-bits.h | 8 ++++--
>> arch/mips/include/asm/pgtable.h | 48
>> ++++++++++++++++++++++++++++++++++--
>
> this breaks all 32bit builds where CPU support RIXI, because it
> overflows
> pgtable_bits.
I think we'd need to make PTEs 64-bit at some point.
We wanted to add support for huge-pages on 32-bit MIPS and faced the
same issue.
-Paul
> Thomas.
>
> --
> Crap can work. Given enough thrust pigs will fly, but it's not
> necessarily a
> good idea. [ RFC1925,
> 2.3 ]
于 2020年4月27日 GMT+08:00 上午12:54:42, Thomas Bogendoerfer <[email protected]> 写到:
>On Tue, Apr 21, 2020 at 05:15:27PM +0800, Guoyun Sun wrote:
>> User space checkpoint and restart tool (CRIU) needs the page's change
>> to be soft tracked. This allows to do a pre checkpoint and then dump
>> only touched pages.
>>
>> Signed-off-by: Guoyun Sun <[email protected]>
>> ---
>> arch/mips/Kconfig | 1 +
>> arch/mips/include/asm/pgtable-bits.h | 8 ++++--
>> arch/mips/include/asm/pgtable.h | 48 ++++++++++++++++++++++++++++++++++--
>
>this breaks all 32bit builds where CPU support RIXI, because it overflows
>pgtable_bits.
Probably make a fixup patch to guard
_PAGE_SOFT_DIRTY_SHIFT with
CONFIG_HAVE_ARCH_SOFT_DIRTY
would be a better option?
Btw: It's really selfish that only enable SOFT_DIRTY for Loongson
but occupied a bit in pagetable for all MIPS systems.
I'd suggest select HAVE_ARCH_SOFT_DIRTY for all 64BIT MIPS systems.
Or provide config options to let expert users decide what feature they need.
Thanks.
>
>Thomas.
>
--
Jiaxun Yang
On Sun, Apr 26, 2020 at 07:09:26PM +0200, Paul Cercueil wrote:
> >> arch/mips/Kconfig | 1 +
> >> arch/mips/include/asm/pgtable-bits.h | 8 ++++--
> >> arch/mips/include/asm/pgtable.h | 48
> >>++++++++++++++++++++++++++++++++++--
> >
> >this breaks all 32bit builds where CPU support RIXI, because it overflows
> >pgtable_bits.
>
> I think we'd need to make PTEs 64-bit at some point.
I'm taking patches ;-) Any idea how much performance impact we might
see by this ?
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
Hi Guoyun,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.7-rc3 next-20200428]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Guoyun-Sun/mips-mm-Add-page-soft-dirty-tracking/20200423-050636
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 18bf34080c4c3beb6699181986cc97dd712498fe
config: mips-randconfig-a001-20200428 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project f30416fdde922eaa655934e050026930fefbd260)
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install mips cross compiling tool for clang build
# apt-get install binutils-mips-linux-gnu
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <[email protected]>
All errors (new ones prefixed by >>):
>> ld.lld: error: undefined symbol: __compiletime_assert_148
>>> referenced by init.c:453 (arch/mips/mm/init.c:453)
>>> mm/init.o:(mem_init) in archive arch/mips/built-in.a
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]